CN105182229A

CN105182229A - Electric power switch action time dynamic measurement method and application, and electric power switch AC zero crossing point accurate control method and application

Info

Publication number: CN105182229A
Application number: CN201510607734.0A
Authority: CN
Inventors: 郑贵林
Original assignee: Individual
Current assignee: Individual
Priority date: 2015-09-22
Filing date: 2015-09-22
Publication date: 2015-12-23
Anticipated expiration: 2035-09-22
Also published as: CN105182229B; WO2017049907A1

Abstract

The present invention relates to an electric power switch action time dynamic measurement method and application, and an electric power switch AC zero crossing point accurate control method and application. The electric power switch action time dynamic measurement method comprises the following steps of 1) before sending out a switching or cut-off action command to an electric power switch, applying a high-frequency carrier at the input side of the electric power switch as a detection signal source, at the same time, detecting the applied high-frequency carrier at the output side of the electric power switch; 2) sending out the switching or cut-off action command to the electric power switch, and calculating the switching or cut-off action time of the electric power switch by taking the time of sending out the switching or cut-off action command as the starting action time of the switch, and taking the time of starting detecting an applied high-frequency carrier signal at the output side of the electric power switch as the time of the switch of finishing the switching action, or taking the time when the applied high-frequency carrier signal is detected to lose at the output side of the electric power switch as the time of the switch of finishing the cut-off action. According to the method of the present invention, the switching action time of the electric power switch can be measured accurately.

Description

Power switch kinetic measurement actuation time and ac zero-crossing point accuracy control method and application

Technical field

The present invention relates to a kind of power switch dynamic measurement method actuation time, also relate to a kind of power switch dynamic measurement system actuation time, in addition, also relate to said method or the application of system in power switch ac zero-crossing point accurately control, power switch ac zero-crossing point precision Control Technology of the present invention can be applicable to mesohigh field.

Background technology

Consumer nearly all in the world is all connected in power supply grid by Switch equipment at present, current electrical network mainly adopts the alternating current of 50hz or 60hz, and the feature of alternating current is that voltage, electric current are according to the rule cyclical variation of frequency according to sine wave.There are twice voltage over zero and twice current zero-crossing point in sinusoidal wave each cycle, and since the century, can close at voltage over zero, current zero-crossing point disjunction is the pursuit of perfect switch always.Alternating current completes switching in the zero crossing moment, greatly will reduce the impact of switching operation to electrical network, load and switch itself, realizes dividing without electric arc, disconnected, can effective guarantee supply side and electricity consumption side safe, stablize, the serviceable life of prolongation electrical equipment.

For mechanical type electric switch, research direction is mainly impacted around reduction sealing voltage, is reduced and even stop breaking current and carry out, the intersection that has been born current interruption formula switch, vacuum extinction switch, sulfur hexafluoride arc-suppressing switch etc.Although low tension switch mostly is air switch, along with the increase of load type, capacity, the life-span of air switch is general comparatively of short duration.According to authentication specifications, it is just qualified that full load can bear 3000 safe opening and closings, the day work intensity growing compared to current industrial processes, this index from current industrial electric demand for control gap very away from, significantly limit the failure-free operation cycle of industrial automation system, threaten the Electrical Safety of commercial unit, be also difficult to require switch frequent start-stop and reduce the energy-saving and cost-reducing demand of idle running rate more.In addition, due to operating passing zero cannot be completed accurately, the each disjunction of switch all can be subject to burning of electric arc, contact resistance constantly increases, the power consumption of switch and temperature rise all in continuous rising, with load in inductive load, produce superpotential because electric current is non-vanishing due to when voltge surge when non-zero voltage closes and disjunction, affect the life-span of electrical equipment, electrical network, also due to continuous impact, produces harmonic wave, reduces power supply quality.

The principle of work of the power switch such as switch or isolating switch is that powered coil produces torsion, realizes the input action of mechanical switch or isolating switch or cuts off action to powered coil pulse triggering signal of the mechanical movement part of switch or isolating switch.The operating passing zero of switch or isolating switch, first the zero crossing moment of supply side voltage, electric current will be obtained, again according to the input of switch or isolating switch or cut off actuation time, be collectively referred to as described input actuation time and cutting off switching actuation time actuation time, determine what moment to send switching action command in advance to switch or isolating switch in, switching can just be completed at voltage or current zero-crossing point moment to make switch or isolating switch.

For switch or the measurement of Circuit Breaker Switching actuation time, be exactly want detector switch or isolating switch after acquisition switching action command, change the required time to switch or isolating switch state output terminal.

The measurement of switch or Circuit Breaker Switching actuation time, when switch or isolating switch do not access strong power system, is easy to just can accurately measure.Only need add a high level at the input side of switch or isolating switch, then detect whether there is this high level at outgoing side, when receiving this high level signal, switch or closing of power circuit breaker being described, when not receiving this high level signal, then illustrating that switch or isolating switch disconnect.

But when switch or isolating switch access electric power system, as access 400Vac voltage or mesohigh during electric power system as 10KV-1000KV voltage, directly add the switching motion time measurement method of high level signal at the input side of switch or isolating switch obviously unworkable.So, zero crossing mechanical switch control technologys all is at present all the switch motion time detection device by off-line, measures mechanical closure or the break of switch in advance, by surveyed parameters input in computing machine, as each parameter controlling each switch or isolating switch operating passing zero.Because different switch or Circuit Breaker Switching have discreteness, nonuniformity actuation time, course of action is by reasons such as action frequency affect, facts have proved, the above-mentioned control technology setting the parameter of operating passing zero in advance in a computer, can not ensure to make described switch or isolating switch carry out operating passing zero exactly, and because the operating passing zero design of anticipation, and in fact can really cannot realize operating passing zero, bring new electric fault.Special in the switch in mesohigh electric power system or isolating switch etc., this method cannot be applied completely, because once there is phenomenon of arc discharge in the power switch in mesohigh electric power system, consequence very serious (can cause blast or burning), so the uncertainty that cannot receive that this instability brings at all.

Summary of the invention

Goal of the invention of the present invention is to provide a kind of power switch dynamic measurement method actuation time and a kind of power switch dynamic measurement system actuation time, utilizes the method or system, accurately can measure the switching actuation time of power switch.

Goal of the invention of the present invention is achieved through the following technical solutions: a kind of power switch dynamic measurement method actuation time, described actuation time and switching actuation time, refer to that power switch obtains switching action command and changes the required time to power switch state output terminal, comprise and drop into actuation time and switch and close the time of mechanical action and cut off the actuation time of actuation time and switch cutoff electric loop, described power switch dynamic measurement method actuation time specifically comprises the steps:

1) before send input or cut-out action command to described power switch, there is the high frequency carrier of suitable intensity as sensed signal sources in the input side applying of described power switch, detect at the outgoing side of described power switch the high frequency carrier applied simultaneously, described high frequency carrier refers to the carrier wave of frequency far above power frequency, and frequency should be generally more than 1000 times of power frequency;

2) input action command is sent to described power switch, with the time that sends of described input action command for the switch origination action time, to start to detect that the time of applied high-frequency carrier signal completes the time of input action for switch at the outgoing side of described power switch, calculate the input actuation time of described power switch; Or

3) cut-out action command is sent to described power switch, with the time that sends of described cut-out action command for the switch origination action time, to detect that at described power switch outgoing side time of losing applied high-frequency carrier signal completes the time of cut-out action for switch, calculate the cut-out actuation time of described power switch.

Above-mentioned applying has the high frequency carrier of suitable intensity, refers to that the intensity of carrier signal should enable to obtain applied carrier signal the outgoing side of power switch is clear.Decay due to high-frequency carrier signal is subject to the impact of transmission range and periphery radio interference, therefore, the concrete frequency of carrier signal and intensity, different according to different electric pressure, the different power switch by capacity, the high-frequency carrier signal signal to noise ratio snr that power switch outgoing side specifically should be made to receive is not less than 5db.

The invention also discloses a kind of power switch dynamic measurement system actuation time, comprise embedded microprocessor module, high frequency carrier coupled circuit and high frequency carrier parser circuitry;

Described high frequency carrier coupled circuit input end is connected with described embedded microprocessor module, output terminal is connected with the input side of described power switch, described high frequency carrier parser circuitry input end is connected with the outgoing side of described power switch, and output terminal is connected with described embedded microprocessor module;

Described embedded microprocessor module, drop into for sending to described power switch or cut off action command, the time that sends of recording described input or cut-out action command is the switch origination action time, and before send input or cut-out action command to described power switch, output has the high-frequency carrier signal of suitable intensity to described high frequency carrier coupled circuit;

Described high frequency carrier coupled circuit, for being coupled to the input side of described power switch by the high-frequency carrier signal received;

Described high frequency carrier parser circuitry, for resolving the high-frequency carrier signal of described power switch outgoing side and outputting to described embedded microprocessor module;

Described embedded microprocessor module, also for detecting the high-frequency carrier signal of described power switch outgoing side, record starts to detect that the time of applied high-frequency carrier signal is the time that switch completes input action, record detects that the time losing applied high-frequency carrier signal is that switch completes and cuts off actuation time, determines input actuation time of described power switch and cuts off actuation time.

Because high-frequency carrier signal frequency is far away higher than power frequency, therefore, above-mentioned testing process is not by Hz noise.

As a kind of preferred implementation, described power switch dynamic measurement system actuation time also comprises the first buffer circuit and the second buffer circuit, described buffer circuit is for isolating forceful electric power and light current, described first buffer circuit is connected between described embedded microprocessor module and described high frequency carrier coupled circuit, described second buffer circuit is connected between described embedded microprocessor module and described high frequency carrier parser circuitry, described embedded microprocessor module and described power switch are inputted, the forceful electric power of outgoing side separates, be conducive to the safe operation of system.

As high frequency carrier coupled circuit, the preferred implementation of high frequency carrier parser circuitry: described high frequency carrier coupled circuit and described high frequency carrier parser circuitry are by high-voltage capacitance and Hi-pass filter composition, described Hi-pass filter is formed by a resistance and a capacitances in series, one end of described high-voltage capacitance is connected with the series connection mid point of electric capacity with resistance in described Hi-pass filter, the other end of described high-voltage capacitance connects to described embedded microprocessor module, the electric capacity of described Hi-pass filter is connected with the live wire of described power switch input side or outgoing side, the resistance of described Hi-pass filter is connected with the zero line of described power switch input side or outgoing side.

Preferred implementation as described buffer circuit:

Described first buffer circuit comprises: the first optocoupler and the first triode;

Described second buffer circuit is made up of the second optocoupler;

The high-frequency carrier signal that described embedded microprocessor module exports outputs to described first triode after described first light-coupled isolation, drive described first triode signal to be outputted to described high frequency carrier coupled circuit, the signal that described high frequency carrier parser circuitry exports outputs to described embedded microprocessor module after described second light-coupled isolation.

The output terminal of described second optocoupler is connected with the I/O mouth detecting pin as described embedded microprocessor module on off operating mode, described embedded microprocessor module: for while send input action command to described power switch, trigger the timer timing corresponding with described power switch, the external interrupt of open corresponding with described power switch I/O mouth, and after the I/O mouth corresponding with described power switch receives external interrupt signal, read the value of the timer corresponding with described power switch and close this timer and external interrupt corresponding to the I/O mouth corresponding with described power switch, using the value of the timer read as the input actuation time of described power switch, described embedded microprocessor module: also for while send cut-out action command to described power switch, trigger the timer timing corresponding with described power switch, and enter Interruption after the full certain time interval T of timer timing is set, the external interrupt that simultaneously open corresponding with described power switch I/O mouth is corresponding, T is greater than the cut-out actuation time of described power switch, and when the I/O mouth corresponding with described power switch receives external interrupt signal at every turn, read the value of the timer corresponding with described power switch, after the timer Interruption corresponding with described power switch, close this timer and external interrupt corresponding to the I/O mouth corresponding with described power switch, the value of the timer read when the I/O mouth corresponding with described power switch receives external interrupt signal is for the last time as the cut-out actuation time of described power switch.

The present invention also provides a kind of power switch ac zero-crossing point accuracy control method and a kind of power switch ac zero-crossing point precise control device.

Control a method for power switch operating passing zero, comprise the steps:

After receiving switch command, according to make delay parameter or disjunction delay parameter, at closure time point or the break point of setting, according to described make delay parameter or disjunction delay parameter, send to described power switch in advance and drop into or cut off action command, so that described power switch just completes at the closure time of described setting point or break point and drops into or cut off action, the closure time point of described setting or break point are the n-th follow-up zero crossing moment of described power switch input side alternating current, n >=1;

It is characterized in that, described make delay parameter or disjunction delay parameter obtain in the following way:

Measure described power switch each switching actuation time by power switch switching On-line Measuring Method actuation time according to claim 1, and save as history detection record;

The switching actuation time of power switch next time according to the mathematical model prediction be based upon on described power switch switching history actuation time detection record basis;

Described make delay parameter is the difference that described closure time point and described power switch drop into predicted value actuation time; Described disjunction delay parameter is the difference that described break point and described power switch cut off predicted value actuation time.

Described mathematical model detects slip window sampling according to successive ignition and KALMAN kalman filter method is set up.

Described closure time point and break point set in the following way:

After receiving switch command, detect the state of described power switch, if described power switch is current is closure state, detect the current zero-crossing point moment of described power switch input side alternating current, described break point is set according to the described current zero-crossing point moment, if described power switch is current be off state, detects the voltage over zero moment of described power switch input side alternating current, set described closure time point according to the described voltage over zero moment.

The invention also discloses a kind of power switch ac zero-crossing point precise control device, comprising:

Alternating current voltage zero cross detection circuit, be connected with described power switch input side, for detecting described power switch input side alternating current voltage, and described alternating current voltage waveform being arranged, exporting the signal in the saltus step of alternating current voltage zero crossing moment waveform generation;

AC current zero cross detection circuit, be connected with described power switch input side, for detecting described power switch input side AC current, and described AC current waveform being arranged, exporting the signal in the saltus step of AC current zero crossing moment waveform generation;

Described power switch dynamic measurement system actuation time;

Embedded microprocessor module in described power switch dynamic measurement system actuation time, also for receiving key order, and after receiving described switch command, according to make delay parameter or disjunction delay parameter, at closure time point or the break point of setting, according to described make delay parameter or disjunction delay parameter, send to described power switch in advance and drop into or cut off action command, so that described power switch just completes input action at the closure time of described setting point or break point or cuts off action, the closure time point of described setting or break point are the n-th follow-up zero crossing moment of described power switch input side alternating current, n >=1, described embedded microprocessor module, also for preserving described power switch each switching actuation time as history detection record, based on described power switch switching history actuation time detection record founding mathematical models, and according to the mathematical model prediction set up switching actuation time of power switch next time, described make delay parameter is the difference that described closure time point and described power switch drop into predicted value actuation time, described disjunction delay parameter is the difference that described break point and described power switch cut off predicted value actuation time, described embedded microprocessor module, also for after receiving described switch command, detect the state of described power switch, output according to described alternating current voltage or current over-zero testing circuit obtains voltage or current zero-crossing point moment, sets described closure time point or break point according to described voltage or current zero-crossing point moment.

A kind of embodiment as described alternating current voltage zero cross detection circuit:

Described alternating current voltage zero cross detection circuit comprises the 3rd optocoupler and the second triode;

Two output terminals of described 3rd optocoupler are connected with collector with the base stage of described second triode respectively, and the collector of described second triode is connected with described embedded microprocessor module;

Described 3rd optocoupler, for gathering the voltage of described power switch input side alternating current, controls the cut-off of described triode in the alternating current voltage zero crossing moment, exports high level skip signal to described embedded microprocessor module.

Another kind of embodiment as described alternating current voltage zero cross detection circuit:

Described alternating current voltage zero cross detection circuit comprises the first operational amplifier;

Described first operational amplifier gathers the voltage difference of described power switch input side, and at its voltage-limiting element in parallel between input end and reverse input end in the same way, for limiting the voltage between operational amplifier two differential input end, described voltage-limiting element is made up of two diodes of reverse parallel connection, described first operational amplifier gets the intermediate level of its two input end as its reference ground, the output terminal of described first operational amplifier is connected with described embedded microprocessor module, in the alternating current voltage zero crossing moment, export skip signal to described embedded microprocessor module.

A kind of embodiment as described AC current zero cross detection circuit:

Described AC current zero cross detection circuit comprises current inductor, the second operational amplifier, voltage comparator;

Two output terminals of described current inductor are connected respectively with two input ends of described second operational amplifier, the output terminal of described second operational amplifier is connected with the input end in the same way of described voltage comparator, the reverse input end ground connection of described voltage comparator, the output terminal of described voltage comparator is connected with described embedded microprocessor module;

Described current inductor, for detecting the current signal of described power switch input side, and exports the voltage signal corresponding to the electric current detected to described second operational amplifier;

Described second operational amplifier, for amplifying the voltage signal of input;

Described voltage comparator, the voltage signal exported for more described second operational amplifier and the size with reference to ground, export skip signal to described embedded microprocessor module when the voltage signal zero passage that described second operational amplifier exports.

Relative to prior art, the present invention has following beneficial effect:

1) power switch dynamic measurement method actuation time of the present invention and system, the switching actuation time of on-line measurement power switch in power switch band forceful electric power situation can be realized, and measurement result is accurate, carrier frequency at 300Khz time, measuring error can be controlled in ± 10us in, utilize power switch dynamic measurement method actuation time of the present invention and system, complete power switch ac zero-crossing point accuracy control method and the device of on-line measurement actuation time of power switch switching, carrier frequency at 300Khz time, make the error of power switch operating passing zero narrow down to ± 30us between, and this error also reduces further by improving carrier frequency, experimental results demonstrate, power switch ac zero-crossing point accuracy control method of the present invention and device are a kind of for solving low pressure, mesohigh power switch, realize alternating voltage zero-crossing point under state of nature to close, stablizing of alternating current zero crossing disjunction, reliably, economic technical scheme, utilizing power switch ac zero-crossing point accuracy control method of the present invention and device can control power switch no-voltage, to impact zero point closed and without electric arc disjunction at zero point,

2) power switch ac zero-crossing point accuracy control method of the present invention and device, merge the mathematical model that the micro-untreated successive ignition of embedding detects slip window sampling and KALMAN kalman filter method statistical forecast precision, lot of experiments and practical application prove, the present invention is that a kind of precision of prediction improves constantly with power switch switching frequency until stable technical scheme, and the present invention program can realize power switch operating passing zero precision of prediction and reach 10-50us.

Accompanying drawing explanation

Fig. 1 is the circuit theory diagrams of the specific embodiment of alternating current voltage zero cross detection circuit in power switch ac zero-crossing point precise control device of the present invention;

Fig. 2 is the oscillogram of the signal that in Fig. 1, the second triode Q404 collector exports;

Fig. 3 is the circuit theory diagrams of another specific embodiment of alternating current voltage zero cross detection circuit in power switch ac zero-crossing point precise control device of the present invention;

Fig. 4 is the oscillogram of the first operational amplifier LM358 output terminal in Fig. 3;

Fig. 5 is the circuit theory diagrams of the specific embodiment of AC current zero cross detection circuit in power switch ac zero-crossing point precise control device of the present invention;

Fig. 6 is the voltage oscillogram of voltage comparator LM393 input end in Fig. 5;

Fig. 7 is the voltage oscillogram of voltage comparator LM393 output terminal in Fig. 5;

Fig. 8 is the circuit theory diagrams of power switch dynamic measurement system actuation time medium-high frequency carrier wave coupled circuit of the present invention, high frequency carrier parser circuitry specific embodiment;

Fig. 9 is the circuit theory diagrams of buffer circuit specific embodiment in power switch dynamic measurement system actuation time of the present invention;

Figure 10 is the oscillogram of the second optocoupler OP402 input end in Fig. 9;

Figure 11 is the oscillogram of the second optocoupler OP402 output terminal in Fig. 9.

Embodiment

Alternating current zero crossing switching technology mainly contains two kinds at present, one is directly use thyristor as the switching device of alternating current zero crossing switching, the response speed of this method is very fast, when ac zero-crossing point being detected, control thyristor at once and complete switching action, this method can accomplish accurate operating passing zero, but also there is certain pressure drop during turn on thyristors, when the electric current flow through is larger, the power consumption of thyristor is very large, heating is serious, and thyristor due to withstand voltage limited, anti-overvoltage capacity is far short of what is expected compared with mechanical switch, easily to puncture, cause electric power system instability even fault, two is use thyristor in parallel and switch or isolating switch as the switching device of alternating current zero crossing switching, the response speed of this method is slower, control strategy is more complicated also, before gauge tap or breaker closing, first control thyristor conducting when voltage is zero, after turn on thyristors, allow described switch or breaker closing again, before gauge tap or isolating switch disjunction, first by switch or isolating switch disjunction, after switch or isolating switch disjunction complete, when current zero-crossing point, then thyristor is closed.This switching device is when electric power system stable working state, due to switch or isolating switch in parallel with thyristor, the electric current of the overwhelming majority is shunted by switch or isolating switch, so the loss on thyristor is extremely low, but owing to employing thyristor equally, so there is the withstand voltage limited problem of thyristor too, the breakdown normal work that also can affect this switching device of thyristor.In addition, also it should be noted that, above-mentioned two kinds of methods utilizing thyristor to realize alternating current zero crossing switching, all cannot apply in the electric power system of mesohigh.

The invention discloses a kind of power switch dynamic measurement method actuation time and system, to realize the on-line measurement of power switch switching actuation time.In addition, the invention also discloses described power switch dynamic measurement method actuation time and the application of system in the control of power switch operating passing zero, i.e. a kind of power switch ac zero-crossing point accuracy control method and device, power switch ac zero-crossing point precise control device of the present invention can be arranged separately, after being connected with power switch, the power switch that can control one or more completes operating passing zero, also can combine with power switch, form Carrier wave detection technique and realize zero excessive mechanical formula electric power switch unit, control the supply line of more than or two.

Power switch ac zero-crossing point accuracy control method of the present invention and device, by power switch operating passing zero control errors within 50us, can be used for the control of power switch operating passing zero in mesohigh electric power system.

Power switch ac zero-crossing point precise control device of the present invention comprises alternating current voltage zero cross detection circuit, AC current zero cross detection circuit and power switch dynamic measurement system actuation time.

The method that power switch ac zero-crossing point precise control device of the present invention controls power switch operating passing zero is as follows:

A kind of power switch ac zero-crossing point accuracy control method, comprises the steps:

Described make delay parameter or disjunction delay parameter obtain in the following way:

Measure described power switch each switching actuation time by power switch dynamic measurement method actuation time (will talk about hereinafter), and save as history detection record;

Described make delay parameter is the difference that described closure time point and described power switch drop into predicted value actuation time; Described disjunction delay parameter is the difference that described break point and described power switch cut off predicted value actuation time; Described mathematical model detects slip window sampling according to successive ignition and KALMAN kalman filter method is set up.

Alternating current voltage zero cross detection circuit

Alternating current voltage zero cross detection circuit, be connected with described power switch input side, for detecting described power switch input side alternating current voltage, and described alternating current voltage waveform being arranged, exporting the signal in the saltus step of alternating current voltage zero crossing moment waveform generation.

The first link detecting the voltage over zero moment is the voltage of perception power switch input side, generally can select voltage transformer (VT) sense voltage, and optical fiber or Phototube Coupling sensor also can be adopted also to be optocoupler sense voltage.Adopt the voltage of two-way optocoupler perception power switch input side alternating current in the present embodiment, certainly, also can select other any high voltage bearing optocoupler.

Fig. 1 is the circuit theory diagrams of the specific embodiment of alternating current voltage zero cross detection circuit, and as shown in the figure, the alternating current voltage zero cross detection circuit of the present embodiment mainly comprises the 3rd optocoupler OP3 and the second triode Q404.The model of the 3rd optocoupler OP3 selected in the present embodiment is TLP280, and it is a bidirectional linear optocoupler, the linearly of input end can be fed back to output terminal, therefore can reflect the waveform of alternating current voltage in real time.

In the present embodiment, the particular circuit configurations of alternating current voltage zero cross detection circuit is as follows: the input end pin 1 of the 3rd optocoupler OP3 is connected with the live wire L of power switch input side by resistance R26, input end pin 2 meets the zero line N of power switch input side, the output terminal pin 3 of the 3rd optocoupler OP3 is connected with the base stage of the second triode Q404 by resistance R28, the output terminal pin 4 of the 3rd optocoupler OP3 is connected with the collector of the second triode Q404 by resistance R27, and using the collector of the second triode Q404 as the output of alternating current voltage zero cross detection circuit, export RelaySamMain signal to embedded microprocessor module, the output terminal pin 4 of the 3rd optocoupler OP3 is also connected with power supply VCC, the output terminal pin 3 of the 3rd optocoupler OP3 also connects with reference to ground GND by resistance R29, the emitter of triode Q404 also with reference to ground GND is connected.

To connect a large resistance R26 at the input end of the 3rd optocoupler OP3, for limiting the electric current flowing through the 3rd optocoupler OP3, alternating current is through the 3rd optocoupler OP3 Phototube Coupling, export one and be similar to the alternating voltage waveform signal after having carried out full-wave rectification, this signal outputs to the base stage of the second triode Q404, controls the second triode Q404 conducting or cut-off.When the second triode Q404 base voltage is higher than certain value (being generally 0.7V), the second triode Q404 collector, emitter enter conducting state, collector output low level; When the second triode Q404 base voltage is lower than 0.7V, the second triode Q404 is in cut-off state, and collector exports high level.

Fig. 2 is the oscillogram of the signal that the second triode Q404 collector exports, in Fig. 2, sine wave is the voltage waveform of power switch input side alternating current, pulse signal waveform is the waveform that the second triode Q404 collector exports, visible: in the present embodiment, alternating current voltage zero cross detection circuit is when power switch input side voltage over zero being detected, a high level skip signal will be exported as voltage over zero moment notification signal.Therefore, by detecting the zero crossing moment of this Signal analysis voltage.As the rising edge by detecting above-mentioned pulse signal, identify the zero crossing moment of voltage, but this rising edge moment should carry out certain time delay, this time delay is the half of the time that pulse square wave high level continues.

The present invention also can use operational amplifier or voltage comparator to carry out shaping to alternating current voltage waveform, output signal is made to become the cycle square wave consistent with ac period, again by identifying the edge of this square wave and rising edge or negative edge, identify the zero crossing moment of alternating current voltage, to promote the measuring accuracy of power switch state transformation period point.

As shown in Figure 3, Fig. 3 is the circuit theory diagrams of another specific embodiment of alternating current voltage zero cross detection circuit.The alternating current voltage zero cross detection circuit of this embodiment mainly comprises the first operational amplifier LM358 (LM358 is the model of this operational amplifier).First operational amplifier LM358 is a dual operational amplifier, and inside includes two independently operational amplifiers, is suitable for single supply mode of operation, is also applicable to dual power supply mode of operation.

In this embodiment, alternating current voltage zero cross detection circuit particular circuit configurations is: the IN1+ of input end in the same way of the first operational amplifier LM358 is connected with the live wire L of power switch input side by resistance RW2, reverse input end IN1-is connected with the zero line N of power switch input side by resistance RW1, gather the voltage difference of power switch input side, first operational amplifier LM358 input end IN1+ in the same way, a voltage-limiting element in parallel between reverse input end IN1-, for limiting the first operational amplifier LM358 input end IN1+ in the same way, voltage between reverse input end IN1-, voltage-limiting element is by two diode DW1 of reverse parallel connection, DW2 is formed.Resistance RW2, RW1 flow through the electric current of diode for limiting.Two diode DW1, DW2 of reverse parallel connection are used for the voltage clamp of the first operational amplifier LM358 differential input end within 0.7V.Resistance RW3 and RW4 is in parallel with voltage-limiting element again after connecting, and the intermediate point that resistance RW3 with RW4 is connected is connected with the first operational amplifier LM358 earth terminal GND, and the first operational amplifier LM358 earth terminal GND connects with reference to ground.The intermediate level of getting the first operational amplifier LM358 input end IN1+, reverse input end IN1-in the same way in the present embodiment is as the first operational amplifier LM358 with reference to ground, and the differential signal that the first operational amplifier LM358 is inputted has reliably with reference to ground.The output terminal OUT1 of the first operational amplifier LM358 is as the output of alternating current voltage zero cross detection circuit, export RelaySam0 signal, the power end VCC of the first operational amplifier LM358 is connected with its output terminal OUT1 by resistance RW5, meanwhile, the power end VCC of the first operational amplifier LM358 be also energized hold CVG with reference to be connected.

When the voltage over zero of alternating current, the first operational amplifier LM358 of the present embodiment has good common-mode rejection properties and noiseproof feature, thus the moment of the voltage over zero of alternating current accurately can be detected.Fig. 4 is the oscillogram of the first operational amplifier LM358 output terminal OUT1.In Fig. 4, sine wave is the voltage waveform of power switch input side alternating current, and square wave is the waveform that operational amplifier exports.What as can be seen from the figure the first operational amplifier LM358 exported is the square wave of standard, and the cycle is 20MS, with the cycle consistent (60Hz principle roughly the same) of the 50Hz alternating current of input, the edge of square wave is just in time in alternating current voltage zero crossing place, therefore just accurately can be identified the zero crossing moment of alternating current voltage by the edge of the square wave of detection first operational amplifier LM358 output.

Through overtesting and generalized analysis, based on the more easy economy of method that the 3rd optocoupler OP3 detects the alternating current voltage zero crossing moment, comparatively recommend.

AC current zero cross detection circuit

AC current zero cross detection circuit, be connected with described power switch input side, for detecting described power switch input side AC current, and described AC current waveform being arranged, exporting the signal in the saltus step of AC current zero crossing moment waveform generation.

For the detection in AC current zero crossing moment, Current Transformer is first made to isolate the current signal obtaining power switch input side, by Power Electronic Circuit, this current signal is changed into voltage signal again, then, detect the zero crossing moment of this voltage signal, just can obtain the zero crossing moment of AC current, concrete circuit as shown in Figure 5.

The AC current zero cross detection circuit of this embodiment comprises current inductor, (AD623 is the model of this operational amplifier to the second operational amplifier A D623, herein simultaneously using it as code name, to distinguish other operational amplifier), (LM393 is the model of this operational amplifier to voltage comparator LM393, herein simultaneously using it as code name, to distinguish other comparer).

Concrete circuit structure is: current inductor forms by according to the standard current transformer I202 (adopting no-load voltage ratio to be the current transformer of 2500:1 in the present embodiment) of electric pressure and the precision resister R213 of 100 Ω, precision resister R213 is connected between two output pins of standard current transformer I202, and current signal is changed into voltage signal.Two input ends of the second operational amplifier A D623 are connected with the two ends of described precision resister respectively, and in Fig. 5, CT1, CT2 are the input pins of the voltage signal of electric current after precision resister transforms that current transformer senses.The two input end pin twos, 3 of the second operational amplifier A D623 also respectively by substitutional resistance R203, R204 with reference to be connected, this structure is used for the ground level voltage signal of the second operational amplifier A D623 input end being pulled down to the second operational amplifier A D623, makes the voltage signal of input with having stable reference.Second operational amplifier A D623 adopt dual power supply, its pin 7,4 is connected with power supply 3V3 ,-3V3 respectively, pin 7 simultaneously by electric capacity C201 with reference be connected, to realize decoupling.A resistance Rg201 is connected, for arranging the gain of the second operational amplifier A D623 between the pin one, 8 of the second operational amplifier A D623.The pin 5 of the second operational amplifier A D623 connects with reference to ground.The output terminal pin 6 of the second operational amplifier A D623 is connected with the IN1+ of input end in the same way of voltage comparator LM393 by resistance R208.Voltage comparator LM393 is a kind of twin voltage comparer integrated chip, and its IN1+ of input end in the same way also connects with reference to ground, for preventing the overtension of voltage comparator LM393 differential input end by stabilivolt D203.The reverse input end of voltage comparator LM393 connects with reference to ground, voltage comparator LM393 is for comparing the output voltage of the second operational amplifier A D623 and the size with reference to ground voltage, when the output voltage of the second operational amplifier A D623 is greater than with reference to ground voltage, export high level.The earth terminal GND of voltage comparator LM393 connects with reference to ground, power supply termination power 3V3, and output terminal OUT1 is the output of AC current zero cross detection circuit, exports RelaySam1 signal, and output terminal OUT1 is also connected with power supply 3V3 by pull-up resistor R209.The input of another passage in voltage comparator LM393, output terminal all with reference to be connected.

A second operational amplifier A D623 is added before voltage comparator LM393, one is the high impedance input characteristics that make use of amplifier, reduce the impact on the second operational amplifier A D623 output signal as far as possible, two is utilize the second operational amplifier A D623 suitably to be amplified by signal, thus guarantees also the AC current zero crossing moment can accurately be detected when electric current is less.When connecing a pure resistor load, the signal waveform of the voltage comparator LM393 input end obtained as shown in Figure 6, signal waveform shown in Fig. 6 is that AC current signal is through transforming, signal after amplification, this signal is input to the IN1+ of input end in the same way of voltage comparator LM393, compare with the earth level of the reverse input end IN1-of voltage comparator LM393, thus the square wave obtained in the saltus step of current zero-crossing point moment, this square-wave waveform structure as shown in Figure 7, as can be seen from Figure 7, the cycle 20ms that the square wave period of voltage comparator LM393 output is corresponding with the ac frequency of power switch input side is consistent.

The zero crossing moment of power switch input side alternating current voltage, electric current can be monitored accurately by above-mentioned alternating current voltage zero cross detection circuit, AC current zero cross detection circuit.Owing to adopting Power Electronic Technique completely, accuracy of detection, all at microsecond scale, relative to relay or the actuation time of isolating switch or the ac period of 50Hz or 60Hz, is that degree of accuracy is very high.

Power switch dynamic measurement system actuation time

Power switch dynamic measurement system actuation time comprises embedded microprocessor module, high frequency carrier coupled circuit and high frequency carrier parser circuitry.

Power switch dynamic measurement system actuation time of the present invention measures the method for power switch switching actuation time, i.e. power switch dynamic measurement method actuation time, and concrete steps are as follows:

1) before send input or cut-out action command to described power switch, there is the high frequency carrier of suitable intensity as sensed signal sources in the input side applying of described power switch, detect at the outgoing side of described power switch the high frequency carrier applied simultaneously;

Embedded microprocessor module MCU produces the high-frequency carrier signal of 100kHz-5MHz, the input side of power switch is coupled to by high frequency carrier coupled circuit, high frequency carrier coupled circuit can select high-voltage capacitance or other carrier wave electric capacity etc., again by high frequency carrier parser circuitry as high-voltage capacitance parses the high-frequency carrier signal of power switch outgoing side, identify power switch state-change finally by embedded microprocessor module MCU, the split-second precision realizing being accurate to high frequency carrier one-period is measured.

The present invention can before sending switching action command to power switch, and the input side to power switch sends high frequency carrier, and can parse described high frequency carrier at the outgoing side of power switch, has no special requirements to the concrete waveform of carrier signal.

High frequency carrier coupled circuit

High frequency carrier coupled circuit is connected with the input side of described power switch, for the high-frequency carrier signal received being coupled to the input side of described power switch.

High frequency carrier parser circuitry

High frequency carrier parser circuitry is connected with the outgoing side of described power switch, for resolving the high-frequency carrier signal of described power switch outgoing side and outputting to described embedded microprocessor module.

As the specific embodiment of high frequency carrier coupled circuit of the present invention and high frequency carrier parser circuitry, as shown in Figure 8:

Described high frequency carrier coupled circuit and described high frequency carrier parser circuitry are by high-voltage capacitance C2 or C4 and Hi-pass filter composition, described Hi-pass filter forms C1 and R1 or C3 and R2 by a resistance and a capacitances in series, one end of described high-voltage capacitance C2 or C4 is connected with the series connection mid point of electric capacity C1 with R1 or C3 with R2 with resistance in described Hi-pass filter, the other end of described high-voltage capacitance C2 or C4 connects to described embedded microprocessor module, electric capacity C1 or C3 of described Hi-pass filter is connected with live wire L or L ' of described power switch input side or outgoing side, the resistance of described Hi-pass filter is connected with the zero line N of the input side of described power switch or outgoing side.

In Fig. 8, electric capacity C1 and resistance R1, electric capacity C3 and resistance R2 form two Hi-pass filters, frequency is only had to the alternating current of 50Hz ~ 60Hz, be equivalent to open circuit, be the square wave (100KHz-5MHz can be set to as required even higher) of 300KHz for high frequency carrier of the present invention as frequency, be equivalent to short circuit.

The high-frequency carrier signal that Micro-processor MCV exports outputs to one end of electric capacity C1 through electric capacity C2, then the input side of power switch is coupled to through electric capacity C1, if at first power switch is in closure state, high-frequency carrier signal exports through closed power switch and arrives electric capacity C3, then be coupled to electric capacity C4 through electric capacity C3, then be coupled to the input port of embedded microprocessor module MCU through electric capacity C4.After power switch disconnects, this high-frequency carrier signal cannot arrive the outgoing side of power switch, and so embedded microprocessor module MCU is namely by identifying the moment that the time identification power switch state output terminal starting can't detect described high-frequency carrier signal changes.Above-mentioned high frequency carrier electric capacity C1, C3, C2, C4 is the Primary Component that carrier wave is measured, high-frequency carrier signal is outputted to switching circuitry except realizing or obtains high-frequency carrier signal from switching circuitry by each electric capacity, to bear simultaneously power switch cross the voltage of electric power, therefore, the voltage withstand class of each electric capacity is relevant to the electric pressure of the power circuit that power switch controls (must be significantly higher than the peak values of ac of the voltage of the power circuit that power switch controls), capacity is relevant with the frequency of the high frequency carrier being applied to power switch input side, frequency is high, the capacity of then required electric capacity is just little, to reach suitable signal to noise ratio (S/N ratio) for parameter configuration basis.

Circuit shown in Fig. 8 not by forceful electric power and light current completely isolated, in order to make system energy safe and stable operation, all can add buffer circuit at the output of embedded microprocessor module MCU high-frequency carrier signal, input end.As shown in Figure 9, in this embodiment, optical coupling isolation circuit is added.

First buffer circuit is connected between described embedded microprocessor module and described high frequency carrier coupled circuit.Second buffer circuit is connected between described embedded microprocessor module and described high frequency carrier parser circuitry.

Described first buffer circuit mainly comprises the first optocoupler OP401 and the first triode Q101.

Described second buffer circuit is formed primarily of the second optocoupler OP402.

In this embodiment, the first optocoupler OP401 of selection, the model of the second optocoupler OP402 are all 6N137, and it has 8 stitch.

The forward input stitch 2 of the first optocoupler OP401 meets power supply 3V3, reverse input stitch 3 is connected with embedded microprocessor module MCU by resistance R401, receive the Pulseout signal that embedded microprocessor module MCU exports, and the conducting when Pulseout signal is low level.Ground pin 5 ground connection of the first optocoupler OP401, export stitch 6 and be connected with power supply 5VDD by pull-up resistor R402, the power supply stitch 8 of the first optocoupler OP401 is also all connected with power supply 5VDD with enable stitch 7, is also connected by electric capacity C401 and DGND simultaneously.First optocoupler OP401 stitch 1,4 vacant.The output stitch 6 of the first optocoupler OP401 is connected with the base stage of the first triode Q101, the emitter of the first triode Q101 is connected with DGND, collector is connected with power supply 5VDDC by resistance R1101, and collector also exports Pulse_out to high frequency carrier coupled circuit as output terminal simultaneously.

The reverse input stitch 3 of the second optocoupler OP402 is connected with high frequency carrier parser circuitry, be connected with power supply 5VDD by resistance R403 simultaneously, the forward input stitch 2 of the second optocoupler OP402 is connected with power supply 5VDD, its ground pin 5 connects with reference to ground, export stitch 6 to be connected with power supply 3V3 by pull-up resistor R404, output to embedded microprocessor module MCU, its power supply stitch 8 and enable stitch 7 meet power supply 3V3 simultaneously, connect with reference to ground decoupling by electric capacity C402 simultaneously, its stitch 1,4 vacant.

If the high-frequency carrier signal of embedded microprocessor module MCU sender waveshape, square wave exports after the first optocoupler OP401 Phototube Coupling, drives the first triode Q101 that this signal is applied to the input side that high frequency carrier coupled circuit is coupled to power switch.Waveform shown in Figure 10 is the waveform of the second optocoupler OP402 input side, and the lower jumping in waveform is along about 2V, and this lower diode of jumping along enough driving the second optocoupler OP402, therefore, the second optocoupler OP402 can by this lower jumping along exporting, and Figure 11 is shown in waveform performance.So embedded microprocessor module MCU jumps edge under only need detecting first, just can judge power switch on off operating mode.Embedded microprocessor module MCU sends high frequency carrier to power switch input side, if after embedded microprocessor module MCU sends input action command to power switch, through time delay, embedded microprocessor module MCU detects the lower jumping edge of high frequency carrier, now can judge that power switch closes, jump the time on edge under the time that sends of record input action command and embedded microprocessor module MCU detect high frequency carrier, power switch drops into and just can accurately obtain actuation time; Before embedded microprocessor module MCU sends and cuts off action command, first send high frequency carrier to power switch input side, outgoing side can detect applied high frequency carrier, when embedded microprocessor module MCU can't detect described high frequency carrier, the cut-out action command of record sends the time and starts the interval of the time that can not receive described high-frequency carrier signal, is power switch and cuts off actuation time.

Embedded microprocessor module MCU also sends the reception condition of front power switch outgoing side high frequency carrier by detecting switching action command, identify the current state of power switch.Certainly, also can arrange current inductor part at power switch outgoing side, whether embedded microprocessor module MCU exists electric current by detecting power switch outgoing side, judges the current state of power switch.

If when utilizing embedded microprocessor module MCU of the present invention to control the switching action of the separate power switch of multichannel, should be each power switch and configure independently timer, to ensure work separate between each power switch.The measurement of multichannel independent power switch on-off actuation time, in order to ensure the time that the moment accurate recording state that embedded microprocessor module MCU can change at power switch state output terminal changes, during program design, on embedded microprocessor module MCU, detect pin for every road power switch configures independently on off operating mode, this on off operating mode detection pin passes through independently interrupt line and is connected with each power switch outgoing side.

The program design of MCU is described below: the output terminal of the second optocoupler OP402 is connected with the I/O mouth detecting pin as embedded microprocessor module MCU on off operating mode, arrange in program this I the corresponding external interrupt instruction of O mouth, and be arranged to the mode of edge triggered interruption.When supposing to start, the state of power switch disconnects, so at this moment, the output terminal of the second optocoupler Q101 is a high level, without any upper jumping, lower jumping edge, embedded microprocessor module MCU sends input action command to power switch, timer starts to drop into timing actuation time to power switch, and the corresponding I of open second optocoupler OP402 the external interrupt instruction of O mouth.Power switch has closed moment, high-frequency carrier signal by be input to by power switch, high frequency carrier parser circuitry, the second buffer circuit corresponding I O mouth, first edge of high-frequency carrier signal will trigger the external interrupt of embedded microprocessor module MCU, MCU enters interrupt service routine, the value of timer is read in interrupt service routine, and timeing closing device and I O external interrupt, the value of the timer read is exactly that power switch drops into actuation time.Power switch is in closure state upon start, MCU sends and sends cut-out action command to power switch, shot timers also enters Interruption after arranging the full 10MS of timer timing, simultaneously the corresponding I of open second optocoupler OP402 the external interrupt of O mouth, and when entering external interrupt service routine at every turn, read the value of timer, after power switch disconnects, second optocoupler OP402 output terminal will become high level, can not trigger afterwards I the external interrupt of O mouth, arrive Deng timing, trigger Interruption, in Interruption service routine, timeing closing device, close external interrupt, the value of timer that so external interrupt of last edging trigger reads is exactly that power switch cuts off actuation time.

As the above analysis, the frequency of high-frequency carrier signal is higher, and the switching measuring the power switch obtained is more accurate for actuation time.Power switch dynamic measurement method actuation time precision of the present invention is high, the cycle of maximum differences two high frequency carrier carrier signals, namely 7 microseconds/300Khz, this error in this patent, even if no longer after filtering and correct, the zero crossing time error of 7um, even mean the voltage of 35KV, its zero crossing voltage error also only only has 70V, deviation is very little, and for the civil power of 400Vac, switch establishes voltage between contact only to only have 0.7V, therefore, precision can meet actual requirement completely.For 500KVac electric pressure, frequency of carrier signal needs higher than 2Mhz, and now because metrical error is only 1um, this deviation makes switch establish voltage between contact to be no more than 140V, and by filtering, this voltage completely can reduce further and control.Power switch dynamic measurement method actuation time of the present invention and application thereof are that the very reliable also highly effective mesohigh field power switch zero passage of one cuts issue-resolution thoroughly as can be seen here.

Claims

1. power switch dynamic measurement method actuation time, described actuation time and switching actuation time, refer to that power switch obtains switching action command and changes the required time to power switch state output terminal, comprise and drop into actuation time and switch and close the time of mechanical action and cut off the actuation time of actuation time and switch cutoff electric loop, described power switch dynamic measurement method actuation time specifically comprises the steps:

1) before send input or cut-out action command to described power switch, apply high frequency carrier as sensed signal sources at the input side of described power switch, detect at the outgoing side of described power switch the high frequency carrier applied simultaneously;

2. power switch dynamic measurement system actuation time, is characterized in that, comprises embedded microprocessor module, high frequency carrier coupled circuit and high frequency carrier parser circuitry;

3. power switch dynamic measurement system actuation time according to claim 2, it is characterized in that, described power switch dynamic measurement system actuation time also comprises the first buffer circuit and the second buffer circuit, described buffer circuit is for isolating forceful electric power and light current, described first buffer circuit is connected between described embedded microprocessor module and described high frequency carrier coupled circuit, and described second buffer circuit is connected between described embedded microprocessor module and described high frequency carrier parser circuitry.

4. power switch dynamic measurement system actuation time according to claim 3, it is characterized in that, described high frequency carrier coupled circuit and described high frequency carrier parser circuitry are by high-voltage capacitance (C2 or C4) and Hi-pass filter composition, described Hi-pass filter is formed (C1 and R1 or C3 and R2) by a resistance and a capacitances in series, one end of described high-voltage capacitance (C2 or C4) is connected with the series connection mid point of resistance in described Hi-pass filter with electric capacity (C1 with R1 or C3 with R2), the other end of described high-voltage capacitance (C2 or C4) connects to described embedded microprocessor module, the electric capacity (C1 or C3) of described Hi-pass filter is connected with the live wire (L or L ') of described power switch input side or outgoing side, the resistance of described Hi-pass filter is connected with the zero line (N) of described power switch input side or outgoing side.

5. power switch dynamic measurement system actuation time according to claim 4, is characterized in that,

Described first buffer circuit comprises: the first optocoupler (OP401) and the first triode (Q101);

Described second buffer circuit is made up of the second optocoupler (OP402);

The high-frequency carrier signal that described embedded microprocessor module exports outputs to described first triode (Q101) after described first optocoupler (OP401) isolation, drive described first triode (Q101) signal to be outputted to described high frequency carrier coupled circuit, the signal that described high frequency carrier parser circuitry exports outputs to described embedded microprocessor module after described second optocoupler (OP402) isolation.

6. power switch dynamic measurement system actuation time according to any one of claim 2 ~ 5 claim, it is characterized in that, the output terminal of described second optocoupler (OP402) is connected with the I/O mouth detecting pin as described embedded microprocessor module on off operating mode, described embedded microprocessor module: for while send input action command to described power switch, trigger the timer timing corresponding with described power switch, the external interrupt of open corresponding with described power switch I/O mouth, and after the I/O mouth corresponding with described power switch receives external interrupt signal, read the value of the timer corresponding with described power switch and close this timer and external interrupt corresponding to the I/O mouth corresponding with described power switch, using the value of the timer read as the input actuation time of described power switch, described embedded microprocessor module: also for while send cut-out action command to described power switch, trigger the timer timing corresponding with described power switch, and enter Interruption after the full certain time interval T of timer timing is set, the external interrupt that simultaneously open corresponding with described power switch I/O mouth is corresponding, T is greater than the cut-out actuation time of described power switch, and when the I/O mouth corresponding with described power switch receives external interrupt signal at every turn, read the value of the timer corresponding with described power switch, after the timer Interruption corresponding with described power switch, close this timer and external interrupt corresponding to the I/O mouth corresponding with described power switch, the value of the timer read when the I/O mouth corresponding with described power switch receives external interrupt signal is for the last time as the cut-out actuation time of described power switch.

7. a power switch ac zero-crossing point accuracy control method, comprises the steps:

Measure described power switch each switching actuation time by power switch dynamic measurement method actuation time according to claim 1, and save as history detection record;

8. power switch ac zero-crossing point accuracy control method according to claim 7, is characterized in that, described mathematical model detects slip window sampling according to successive ignition and KALMAN kalman filter method is set up.

9. a power switch ac zero-crossing point precise control device, is characterized in that, comprising:

Power switch dynamic measurement system actuation time described in any one of claim 2 ~ 6 claim;

10. power switch ac zero-crossing point precise control device according to claim 9, is characterized in that, described alternating current voltage zero cross detection circuit comprises the 3rd optocoupler (OP3) and the second triode (Q404);

Two output terminals of described 3rd optocoupler (OP3) are connected with collector with the base stage of described second triode (Q404) respectively, and the collector of described second triode (Q404) is connected with described embedded microprocessor module;

Described 3rd optocoupler (OP3) is for gathering the voltage of described power switch input side alternating current, control described triode (Q404) cut-off in the alternating current voltage zero crossing moment, export high level skip signal to described embedded microprocessor module.

11. power switch ac zero-crossing point precise control devices according to claim 9, is characterized in that,

Described alternating current voltage zero cross detection circuit comprises the first operational amplifier (LM358);

Described first operational amplifier (LM358) gathers the voltage difference of described power switch input side, and at its voltage-limiting element in parallel between input end and reverse input end in the same way, for limiting the voltage between operational amplifier two differential input end, described voltage-limiting element is made up of two diodes of reverse parallel connection, described first operational amplifier (LM358) gets the intermediate level of its two input end as its reference ground, the output terminal of described first operational amplifier (LM358) is connected with described embedded microprocessor module, in the alternating current voltage zero crossing moment, export skip signal to described embedded microprocessor module.

12. power switch ac zero-crossing point precise control devices according to claim 9, it is characterized in that, described AC current zero cross detection circuit comprises current inductor, the second operational amplifier (AD623), voltage comparator (LM393);

Two output terminals of described current inductor are connected respectively with two input ends of described second operational amplifier (AD623), the output terminal of described second operational amplifier (AD623) is connected with the input end in the same way of described voltage comparator (LM393), the reverse input end ground connection of described voltage comparator (LM393), the output terminal of described voltage comparator (LM393) is connected with described embedded microprocessor module;

Described current inductor, for detecting the current signal of described power switch input side, and exports the voltage signal corresponding to the electric current detected to described second operational amplifier (AD623);

Described second operational amplifier (AD623), for amplifying the voltage signal of input;

Described voltage comparator (LM393), the voltage signal exported for more described second operational amplifier (AD623) and the size with reference to ground, export skip signal to described embedded microprocessor module when the voltage signal zero passage that described second operational amplifier (AD623) exports.

13. 1 kinds of Carrier wave detection techniques realize zero excessive mechanical formula electric power switch unit, it is characterized in that, described mechanical type electric power switch unit comprises the power switch ac zero-crossing point precise control device described in any one of claim 9 ~ 12 claim.