CN100345379C

CN100345379C - Cold/hot state resistance differential value lead switch circuit

Info

Publication number: CN100345379C
Application number: CNB2004100138319A
Authority: CN
Inventors: 蔡世俊; 高鹏; 韩泉栋; 赵胜男
Original assignee: ENGE LANBO MICROELECTRONIC Co Ltd NANJING
Current assignee: Wuxi Suntech Power Co Ltd
Priority date: 2004-01-07
Filing date: 2004-01-07
Publication date: 2007-10-24
Anticipated expiration: 2024-01-07
Also published as: CN1592108A

Abstract

The present invention relates to a switching circuit for loads with large cold and hot state resistance differential values. The present invention provides a switching circuit for loads with cold and hot state resistance differential values, and comprises a thyristor device. The switching circuit is characterized in that the switching circuit also comprises a second harmonic decreasing device; the input terminal of the second harmonic decreasing device is connected with the thyristor device, and the output terminal is connected with a thyristor control electrode. The second harmonic decreasing device outputs a preheating pulse to control a thyristor to be switched on, the purpose for smoothly supplying current is achieved, and finally the loads are provided with rated current. The power supply device of the present invention is used for decreasing the cold and hot state resistance differential values of the loads, and can achieve the purposes for extending the service lives of loads and enabling the harmonic current to achieve country and international standards.

Description

Cold and hot state resistance difference load switching circuit

Technical field

The present invention relates to kind of a switching circuit, particularly a kind of switching circuit that is used for the cold and hot state resistance difference than heavy load.

Background technology

The resistance of conductor can change along with the temperature change of conductor itself.Be that the cold and hot state resistance difference of representative in use exists following problem than heavy load (hereinafter to be referred as load) wherein with light fixture (comprising the car light of doing signal indication, identification light, decorative lamp etc.):

1, by dark during to bright switching, lamp temperatures can not be suddenlyd change synchronously, transient high-current can occur, very easily causes the damage of light fixture at this moment;

2, in the utilization of Alternating Current Power Supply, the appearance of transient high-current also can cause the increase of 2 subharmonic currents, and 2 subharmonic currents are very big to the harm of electrical network, are referred to as electric network pollution.

At this moment, the current waveform that provides for load of switching circuit as shown in Figure 9.

Shorter when switch periods, promptly this class cold and hot state resistance difference is bigger load in the circuit repeatedly break-make (for example light fixture bright repeatedly, go out; Or it is bright, dark; Or flicker variation), two problems can be given prominence to seriously more more than.

Corresponding law or regulation have been formulated to this pollution in a lot of countries, limit the producing and selling and the use of this class circuit light fixture.And this cold and hot state resistance difference is than heavy load these problems in use, adopts in the prior art general control method and circuit all can't eliminate effectively.

Summary of the invention

The present invention is directed to this type of problem and propose solution, utilize novel powering method to reduce the cold and hot state resistance difference of load, prolong load useful life and make harmonic current reach the purpose of country, international standard so as to reaching.

The scheme of finishing above goal of the invention is: a kind of cold and hot state resistance difference load switching circuit, comprise thyristor installation, and it is characterized in that it comprises that is also reduced a second harmonic device, its input termination thyristor installation, the output termination SCR control utmost point; Reduce the conducting of second harmonic device output preheat pulse control controllable silicon, for load provides preheat curent less than rated value, and make controllable silicon in specific phase place conducting, the electric current that thyristor installation output is steadily risen finally provides rated current for load.

Reducing the second harmonic device can be one of following circuit arrangement:

Technical scheme 1, it comprise civil power synchronous circuit, switching signal circuit, preheating delay circuit, phase assignments circuit and or logical circuit; The output of civil power synchronous circuit connects delay circuit and phase assignments circuit, and the output of phase assignments circuit connects or logical circuit, and the output of delay circuit connects or logical circuit, or logical circuit connects the SCR control utmost point; The switching signal circuit connects the phase assignments circuit; The civil power synchronous circuit realizes that this device power supply and civil power are synchronous; The switching signal circuit provides switching signal for the phase assignments circuit; The phase assignments circuit makes the switching signal of switching signal circuit and civil power synchronously and control controllable silicon in specific alternating current angle conducting, reduce the odd energy of alternating current thus, realize odd phase place energy add up and with the adding up and equate of even phase place energy, finally reach the purpose that reduces 2 subharmonic energy; The time interval of delay circuit control preheating waveform; Or logical circuit is exported constant preheat pulse and is controlled the control level of controllable silicon in specific alternating current angle conducting.

The current phase distributor circuit comprises simultaneous switching circuit and phase assignments delay circuit, and the output of civil power synchronous circuit and switching signal circuit connects the switch synchronous circuit, and the output of switch synchronous circuit connects the phase assignments delay circuit; The switch synchronous circuit makes the switching signal of switching signal circuit and civil power synchronous; Phase assignments delay circuit control controllable silicon is in specific alternating current angle conducting.

At this moment, reduce by 2 subharmonic devices and be constant current less than rated value for the preheat curent that load provides.

Technical scheme 2, it comprise switching signal circuit, gradual change preheat circuit, civil power synchronous circuit and or logical circuit 6; The switching signal circuit connects the gradual change preheat circuit, and the output of civil power synchronous circuit connects the gradual change preheat circuit, and the output of gradual change preheat circuit connects or logical circuit connects the SCR control utmost point; The switching signal circuit provides switching signal for simultaneous switching circuit; The civil power synchronous circuit provides synchro source for the gradual change preheat circuit; The gradual change preheat circuit provides the high level pulsewidth of output progressively to increase, and low-level pulse width progressively reduces, until the change pulse of the constant high level of output.

The gradual change preheat circuit comprises voltage integrating meter circuit, variable delay circuit; The output of voltage integrating meter circuit connect variable delay circuit and or logical circuit; Variable delay circuit output connects or logical circuit; The voltage integrating meter circuit make the time-delay of switching signal waveform of input and distortion and finally to or the high level that continues of logical circuit output; Variable delay circuit progressively increases the high level pulsewidth of output pulse, and low-level pulse width progressively reduces and changes the circuit internal resistance by change in voltage.

At this moment, the preheat curent that reducing by 2 subharmonic devices provides for load is the gradual change electric current, from increasing to the load rating electric current gradually less than the load rating electric current.

In technical scheme 1, only adopt the time interval of delay circuit control preheating waveform, for circuit provides constant preheat curent, can slow down the difference of load cold and hot state resistance, but this difference is not enough little, particularly for the part light fixture, preheat curent can not make light fixture apparent in view brightness occur, in the switch light fixture, tangible impact can occur, produce 2 subharmonic currents, can not satisfy the requirement of standard.The present invention's problem has for this reason increased AC current phase energy distribution circuit, and purpose is that the switch of control load is only opened at a certain special angle of alternating current.Because when connecting load, the resistance of load is one and becomes big process that electric current can be more and more littler, trends towards constant through all after dates of several civil powers.Suppose that the waveform identical with the phase place of first waveform that powers to the load is strange ripple, opposite is even ripple, if Qi Bo and even ripple all do not have through phase place energy distribution circuit, and all be complete waveform, the energy that so strange ripple is provided is necessarily greater than energy that even ripple provided, this asymmetric load causes the magnetic saturation of power transformer easily, and is very big to the harm of supply line.But for a specific load, the energy difference of Qi Bo and even ripple is a basic fixed, as long as reduce the energy of strange ripple, to equating to get final product with the energy of even ripple.The time-delay of delay circuit 2 can change to 10mS from 0mS, and the time-delay of 0mS keeps the relation of strange ripple and even ripple constant, and the time-delay of 10mS can be exchanged the relation of strange ripple and even ripple, so at 0mS---and the time-delay that 10mS must exist strange ripple to equate with even wave energy.

Obtain the AC load switching circuit in conjunction with current preheating and current phase energy distribution, realized branch current preheating and current phase energy distribution, reach load life and prolong and the purpose that reduces by 2 subharmonic currents.That light fixture is presented when going out is little bright for size by current preheating simultaneously, reaches the purpose that shows the light fixture profile.

In technical scheme 2, adopt the gradual change preheat circuit, the electric current by load increases to rated current gradually; realize the progressively preheating of load, transient high-current can not occur, reduced harmonic current; promptly do not cause impact, protected the load of similar lamp etc. yet electrical network.

Description of drawings

Fig. 1 is the utility model circuit structural representation

Fig. 2 is the circuit block diagram of the

utility model embodiment

1,2

Fig. 3 is the utility model embodiment 3 circuit block diagrams

Fig. 4 is the electrical schematic diagram of the utility model embodiment 1

Fig. 5 is the electrical block diagram of the utility model embodiment 2

Fig. 6 is the current waveform after the rectification among the utility model embodiment 1

Fig. 7 is the oscillogram of the civil power synchronous circuit output among the utility model embodiment 1

Fig. 8 is the signal waveform of the input SCR control utmost point among the utility model embodiment 1

Fig. 9 is the electrical block diagram of the utility model embodiment 3

The current waveform figure that Figure 10 provides for load for the utility model embodiment 1

Figure 11 is the electrical schematic diagram of the utility model embodiment 3

Figure 12 is the signal waveform of the input SCR control utmost point among the utility model embodiment 3

Embodiment

Embodiment 1

As shown in Figure 1, 2, a kind of cold and hot state resistance difference load switching circuit 1, its a kind of cold and hot state resistance difference load switching circuit, comprise thyristor installation 10, one is reduced second harmonic device 9, its input termination thyristor installation 10, the output termination SCR control utmost point 11; This device output preheat pulse control controllable silicon conducting for load provides preheat curent less than rated value, and makes controllable silicon in specific phase place conducting, to reduce 2 subharmonic energy, provides rated current for load simultaneously.

Reduce second harmonic device 9 comprise civil power synchronous circuit 2, switching signal circuit 3, preheating delay circuit 4, current phase distributor circuit 5 and or logical circuit 6; The output of civil power synchronous circuit 2 connects preheating delay circuit 4 and current phase distributor circuit 5, and the output of current phase distributor circuit 5 connects or logical circuit 6, or logical circuit 6 connects the SCR control utmost point; The output of preheating delay circuit 4 connects or logical circuit 6, and the output of switching signal circuit 3 connects phase assignments circuit 5; The civil power synchronous circuit realizes that this device power supply and civil power are synchronous; The switching signal circuit provides switching signal for the phase assignments circuit; The phase assignments circuit makes the switching signal of switching signal circuit and civil power synchronously and control controllable silicon in specific alternating current angle conducting, reduce the odd energy of alternating current thus, realize odd phase place energy add up and with the adding up and equate of even phase place energy, finally reach the purpose that reduces 2 subharmonic energy; The time interval of delay circuit control preheating waveform; Or logical circuit is exported constant preheat pulse and is controlled the control level of controllable silicon in specific alternating current angle conducting.

Current phase distributor circuit 5 comprises simultaneous switching circuit 51 and phase assignments delay circuit 52, the output of civil power synchronous circuit 2 and switching signal circuit 3 connects switch synchronous circuit 51, the output of switch synchronous circuit 51 connects phase assignments delay circuit 52, and the output of phase assignments delay circuit 52 connects or logical circuit 6; The switch synchronous circuit makes the switching signal of switching signal circuit and civil power synchronous; Phase assignments delay circuit control controllable silicon is in specific alternating current angle conducting.

As shown in Figure 4, thyristor installation is one-way SCR and rectifying device, controllable silicon is connected with load, civil power provides power supply through rectifying device for load and civil power synchronous circuit, the input waveform as shown in Figure 6, synchronous circuit RD among the figure, DW, NOT1, NOT2 forms the 50Hz synchronous circuit, output pulse waveform as shown in Figure 7, (NOT1 exports positive logic to the burst pulse of generation mixed logic near the zero point of alternating current, NOT2 exports negative logic) be used for the synchronous of other circuit: when alternating current voltage does not also reach the TL translation level of NOT1, NOT1 is output as high level, it is 0 that the NMOS2 conducting is put the voltage at C2 two ends rapidly, and this moment, NOT2 output also was low level; After alternating current voltage surpasses the TL translation level of NOT1, the NOT1 output low level, NMOS2 ends, NOT2 exports high level, and charges to C2 by R2, when the voltage of C2 surpass or the TL translation level of door OR after, a preheat pulse control of OR output controllable silicon is realized the preheating to load; Output pulse waveform as shown in Figure 8, drop to the TL translation level of NOT1 when alternating current voltage after, begin again the circulation.Regulate the product of R2, C2, just can change the time of preheating waveform.

The current phase distributor circuit: switching signal through D-LATCH and civil power synchronously after, charge to C1 by R1, the current potential of C1 rises gradually, reach the silicon controlled control level after, the conducting of controllable silicon.By regulating the product of R1, C1, can control controllable silicon in specific alternating current angle conducting, reduce the odd energy of alternating current thus, realize odd phase place energy add up and with the adding up and equate of even phase place energy, finally reach the purpose that reduces 2 subharmonic energy.The current waveform that provides for load as shown in figure 10.

Embodiment 2

Shown in Fig. 1,2 and 5, thyristor installation is a bidirectional triode thyristor, RD, DW, NOT3, C5, R5, C6, R6, NOR2, NOT1, NOT2 form the 50Hz synchronous circuit among the figure, when the voltage of alternating current is higher than the TL translation level of NOT3, the NOT3 output low level, through the anti-phase of NOT4 is high level, narrow negative pulse 1 synchronous with civil power of output behind this high level process differential circuit C6, the R6; When the voltage of alternating current was lower than the TL translation level of NOT3, NOT3 exported high level, through narrow negative pulse 2 synchronous with civil power of output behind differential circuit C5, the R5; Negative pulse 1 and negative pulse 2 through NOR2 and NOT1's or logic after offer other circuit, the operation principle of NOT1, NOT2 and other circuit just with embodiment 1 in identical.

Embodiment 3

Shown in Fig. 3,11, a kind of cold and hot state resistance difference load switching circuit 1, its a kind of cold and hot state resistance difference load switching circuit, comprise thyristor installation 10, one is reduced second harmonic device 9, its input termination thyristor installation 10, the output termination SCR control utmost point 11; This device output preheat pulse control controllable silicon conducting for load provides preheat curent less than rated value, and makes controllable silicon in specific phase place conducting, to reduce 2 subharmonic energy, provides rated current for load simultaneously.

Gradual change preheat circuit 7 with the synchronous pulse of civil power after to prolong be benchmark, progressively increase pulse duration, reach the purpose that increases preheat curent.

Reduce second harmonic device 9 comprise switching signal circuit 3, gradual change preheat circuit 7, civil power synchronous circuit 2 and or logical circuit 6; Switching signal circuit 3 connects gradual change preheat circuit 7, and the output of civil power synchronous circuit 2 connects the gradual change preheat circuit, and logical circuit 6 connects the SCR control utmost point; Switching signal circuit 3 provides switching signal for simultaneous switching circuit; Civil power synchronous circuit 2 provides synchro source for gradual change preheat circuit 7; Gradual change preheat circuit 7 provides the high level pulsewidth of output progressively to increase, and low-level pulse width progressively reduces, until the change pulse of the constant high level of output.

Gradual change preheat circuit 7 comprises voltage integrating meter circuit 71, variable delay circuit 72; Switching signal circuit 3 connects voltage integrating meter circuit 71, the output of voltage integrating meter circuit 71 connect variable delay circuit 72 and or logical circuit 6; Civil power synchronous circuit 2 connects variable delay circuit 72, and the output of variable delay circuit 72 connects or logical circuit 6; The voltage integrating meter circuit make the time-delay of switching signal waveform of input and distortion and finally to or the high level that continues of logical circuit output; Variable delay circuit progressively increases the high level pulsewidth of output pulse, and low-level pulse width progressively reduces and changes the circuit internal resistance by change in voltage.

RD, DW, NOT1, NOT2 form the 50Hz synchronous circuit among the figure, dynamically describe as embodiment 1.When control end was low level, NMOS3 ended, and the voltage on C3 and the C4 all is low level, or door OR1 output low level, not conducting of controllable silicon; After control end becomes high level, charge to C3 by R3, rising along with C3 voltage, NMOS3 enters subthreshold region by cut-off region, the saturation region, linear zone, equivalent resistance reduces gradually, when alternating voltage was high level, NOT2 charged to C4 by NMOS3, in the time of incipient, because the conducting resistance of NMOS3 is very big, NMOS3 needs the very long TL translation level that just can reach OR1 to the charging interval of C4, and the output of OR1 becomes high level, after alternating voltage becomes low level, NOT1 exports high level, the NMOS4 conducting bleeds off the voltage of C4 fast, and the output of OR1 just becomes low; After alternating voltage becomes height once more, repeat the charging process of NMOS3 and C4, but owing to the charging of R3 to C3, the voltage increases of C3, the V of NMOS3 _GSIncrease, equivalent internal resistance reduces, so NMOS3 is faster to the charging rate of C4, the voltage of C4 has reached the transfer voltage of OR1 faster, and the pulse duration of OR1 output also increases; In following one-period, the output pulse width of OR1 continues to increase; Through several all after dates, after R3 had reached the TL translation level of OR1 to the charging of C3, OR1 just exported constant high level.Utilize this method, realized the progressively preheating of load.The output waveform of OR1 is seen Figure 12.

Claims

1, a kind of cold and hot state resistance difference load switching circuit (1) comprises thyristor installation (10), it is characterized in that, it comprises that is also reduced a second harmonic device (9), and it imports termination thyristor installation (10), the output termination SCR control utmost point (11); Reduce the conducting of second harmonic device (9) output preheat pulse control controllable silicon, for load provides preheat curent less than rated value, and making controllable silicon in specific phase place conducting, the electric current that thyristor installation output is steadily risen finally provides rated current for load.

2, according to the described cold and hot state resistance difference of claim 1 load switching circuit (1), it is characterized in that, above-mentioned reduction second harmonic device (9) comprise civil power synchronous circuit (2), switching signal circuit (3), preheating delay circuit (4), current phase distributor circuit (5) and or logical circuit (6);

The output of civil power synchronous circuit (2) connects preheating delay circuit (4) and current phase distributor circuit (5), the current phase branch. the output of distribution road (5) connects or logical circuit (6), the output of preheating delay circuit (4) connects or logic electricity the upper and lower teeth not meeting properly (6), or the output of logical circuit (6) connects the SCR control utmost point (11), and the output of switching signal circuit (3) connects phase assignments circuit (5);

The civil power synchronous circuit realizes that this device power supply and civil power are synchronous;

Switching signal circuit (3) provides switching signal for the phase assignments circuit:

The phase assignments circuit makes the switching signal of switching signal circuit and civil power synchronously and control controllable silicon in specific alternating current angle conducting, reduce the odd energy of alternating current thus, realize odd phase place energy add up and with the adding up and equate of even phase place energy, finally reach the purpose that reduces 2 subharmonic energy;

The time interval of delay circuit control preheating waveform; Or logical circuit is exported constant preheat pulse and is controlled the control level of controllable silicon in specific alternating current angle conducting.

3, according to the described cold and hot state resistance difference of claim 1 load switching circuit (1), it is characterized in that, described reduction second harmonic device (9) comprise switching signal circuit (3), gradual change preheat circuit (7), civil power synchronous circuit (2) and or logical circuit (6);

Switching signal circuit (3) connects gradual change preheat circuit (7), the output of civil power synchronous circuit (2) connects gradual change preheat circuit (7), switching signal circuit (3) is for simultaneous switching circuit provides switching signal, or the output of logical circuit (6) connects the SCR control utmost point (11);

Civil power synchronous circuit (2) provides synchro source for gradual change preheat circuit (7);

Gradual change preheat circuit (7) provides the high level pulsewidth of output progressively to increase, and low-level pulse width progressively reduces, until the change pulse of the constant high level of output.

4, according to claim (2) described cold and hot state resistance difference load switching circuit (1), it is characterized in that, described current phase distributor circuit (5) comprises simultaneous switching circuit (51) and phase assignments delay circuit (52), the output of civil power synchronous circuit (2) and switching signal circuit (3) connects switch synchronous circuit (51), the output of switch synchronous circuit (51) connects phase assignments delay circuit (52), and the output of phase assignments delay circuit (52) connects or logical circuit (6); The switch synchronous circuit makes the switching signal of switching signal circuit and civil power synchronous; Phase assignments delay circuit control controllable silicon is in specific alternating current angle conducting.

5, according to the described cold and hot state resistance difference of claim 3 load switching circuit (1), it is characterized in that, described gradual change preheat circuit (7) with the synchronous pulse of civil power after to prolong be benchmark, progressively increase pulse duration, reach the purpose that increases preheat curent.

According to the described cold and hot state resistance difference of claim 5 load switching circuit (1), it is characterized in that 6, described gradual change preheat circuit (7) comprises voltage integrating meter circuit (71), variable delay circuit (72);

Switching signal circuit 3 connects voltage integrating meter circuit (71), the output of voltage integrating meter circuit (71) connect variable delay circuit (72) and or logical circuit (6); Civil power synchronous circuit (2) connects variable delay circuit (72), and the output of variable delay circuit (72) connects or logical circuit (6);

The voltage integrating meter circuit make the time-delay of switching signal waveform of input and distortion and finally to or the high level that continues of logical circuit output; Variable delay circuit progressively increases the high level pulsewidth of output pulse, and low-level pulse width progressively reduces and changes the circuit internal resistance by change in voltage.