Summary of the invention
For addressing the above problem, the invention provides and a kind ofly can automatically identify load characteristic that inverter connects and according to load characteristic and control inverter is selected the output identification control unit of AC and DC output conversion and inverter thereof, control method, thereby reduce, disturb and power consumption.
The invention provides a kind of output identification control unit, the load characteristic connecing for identifying inverter, and corresponding required electric current is exported in the ac-dc conversion unit of control inverter automatically, comprising: sampling module, kernel control module;
Described sampling module, gathers sample rate current, and the described sample rate current collecting is sent to described kernel control module in exchange conversion unit;
Described kernel control module, receives the described sample rate current value threshold default with it that described sampling module sends; When described sample rate current value is less than threshold value, send control signal and control exchange conversion unit output direct current; When described sample rate current value is greater than threshold value, send control signal and control exchange conversion unit output AC electricity.
The present invention also provides a kind of inverter, and described inverter has output identification control unit as above.
The present invention also provides a kind of system, and described system has the inverter of output identification control unit as above.
The present invention also provides a kind of inverter control method, and described method comprises:
Obtain sample rate current;
Kernel control module, by the described sample rate current threshold default with it, when sample rate current is greater than predetermined threshold value, sends control signal and controls exchange conversion unit output AC electricity; When sample rate current is less than predetermined threshold value, send control signal and control exchange conversion unit output direct current.
As can be seen from the above technical solutions, the embodiment of the present invention has the following advantages:
1, because described sampling module gathers electric current from described exchange conversion unit, and the sample rate current collecting is sent to kernel control module, described kernel control module is by the sample rate current value threshold default with it receiving; When described sample rate current value is less than threshold value, send control signal and control exchange conversion unit output direct current; When described sample rate current value is greater than threshold value, send control signal and control exchange conversion unit output AC electricity.Therefore, described output identification control unit can automatically be identified load characteristic that inverter connects and according to load characteristic and control inverter is selected AC and DC output conversion, thereby reduce, disturb and power consumption.
2, because described output identification control unit also comprises a driver module, therefore when the undertension of the control signal of described kernel control module output is when driving described exchange conversion unit, the control signal of described kernel control module output can send to described exchange conversion unit after driver module is changed.
3, due to kernel control module the control signal level of high output be 5V, cannot directly drive P type metal-oxide-semiconductor Q1, the Q2 of exchange conversion unit, therefore increase N-type metal-oxide-semiconductor Q5, Q6, jointly form N-type multiple tube with Q1, Q2.
4,, because described output identification control unit also comprises a Voltage stabilizing module, the low ripple electric current that therefore high ripple current of unstable voltage can be converted to burning voltage sends to described kernel control module.
5, because described output identification control unit also comprises a division module, therefore can carry out dividing potential drop to being carried in the voltage of described exchange conversion unit, while preventing exchange conversion cell conduction, voltage is excessive is burned.
6, the source electrode that is connected on respectively Q1, Q2 due to R1, R2 one end, the other end is connected on respectively the grid of Q1, Q2; Therefore one end of R6, R7 joins with the grid of Q1, Q2 respectively, and the other end is connected on the source electrode of Q6, Q5, can prevent that when Q6, Q7 conducting the grid of Q1, Q2 and source potential are divided to source voltage to be controlled in 12V, avoids burning out Q1, Q2.
7,, because described output identification control unit also comprises that one for representing the state indicating module of the operating state of described output identification control unit, therefore can obviously show the operating state of described inverter output AC/DC.
8, owing to adopting single-chip microcomputer to control as kernel control module, therefore very convenient to the change of function, only need slightly do to change and just can accomplish output overcurrent protection, for example, by the length of the overcurrent time above R3, judge whether it is that output is moderate.If converted to, exchange after-current still over upper threshold values, can carry out output power-off protection.
9, because FB pin arranges two threshold values, in the middle of threshold value, be window phase, therefore can be for effectively avoiding output state change frequently back and forth under critical phenomena.
Embodiment
Invention provides a kind of and can automatically identify load characteristic that inverter connects and according to load characteristic and control inverter is selected the output identification control unit of AC and DC output and inverter thereof, control method, thereby reduce, disturb.
Below in conjunction with the Figure of description in the present invention, the technical scheme in invention is clearly and completely described, obviously, described embodiment is only the present invention's part embodiment, rather than whole embodiment.Embodiment based in the present invention, those of ordinary skills, not making the every other embodiment obtaining under creative work prerequisite, belong to the scope of protection of the invention.
Embodiment mono-,
As shown in the figure, the invention provides a kind of inverter, described inverter comprises: battery unit, DC chopped-wave unit, isolation voltage transformation unit, rectification unit, exchange conversion unit, output identification control unit.Wherein battery unit, DC chopped-wave unit, isolation voltage transformation unit, rectification unit belong to prior art and unrelated to the invention, do not repeat them here.Described output identification control unit is controlled described exchange conversion unit automatically according to loading condition output AC/DC electricity, thereby when zero load or load are Switching Power Supply, by output direct current, can reduce interference and power consumption.
As shown in Figure 3, circuit diagram for the specific embodiment in exchange conversion unit, described exchange conversion unit comprises: the electric bridge being comprised of 4 field effect transistor (metal-oxide-semiconductor) Q1, Q2, Q3, Q4, from the direct current of rectification unit output, is connected on the input of described electric bridge; The control utmost point of field effect transistor Q1, Q2, Q3, Q4 connects respectively described output identification control unit; Two electric wires of output of electric bridge are called after a and b respectively; Conducting and cut-off under the control signal that each field effect transistor Q1 of electric bridge, Q2, Q3, Q4 send at output identification control unit, thus realize direct current, exchange the conversion output of two states.
As shown in Figure 1, described output identification control unit comprises: sampling module 101, kernel control module 102.
Described sampling module 101, gathers sample rate current, and the described sample rate current collecting is sent to described kernel control module 102 from exchange conversion unit.
Described kernel control module 102, receives the described sample rate current value threshold default with it that described sampling module 101 sends; When described sample rate current value is less than threshold value, send control signal and control exchange conversion unit output direct current; When described sample rate current value is greater than threshold value, send control signal and control exchange conversion unit output AC electricity.
In sum, described sampling module gathers electric current from described exchange conversion unit, and the sample rate current collecting is sent to kernel control module, and described kernel control module is by the sample rate current value threshold default with it receiving; When described sample rate current value is less than threshold value, send control signal and control exchange conversion unit output direct current; When described sample rate current value is greater than threshold value, send control signal and control exchange conversion unit output AC electricity.Therefore, described output identification control unit can be controlled described exchange conversion unit automatically according to loading condition output AC DC electric, thereby can reduce interference and the power consumption of inverter.
As shown in Figure 2, in certain embodiments, described output identification control unit also comprises a driver module, when the undertension of the control signal of described kernel control module output is when driving described exchange conversion unit, the control signal of described kernel control module output sends to described exchange conversion unit after driver module conversion.
As shown in Figure 3, be a specific embodiment of driver module, described driver module comprises: first, second metal-oxide-semiconductor Q5, Q6.Due to kernel control module the control signal level of high output be 5V, cannot directly drive P type metal-oxide-semiconductor Q1, the Q2 of exchange conversion unit, therefore increase N-type metal-oxide-semiconductor Q5, Q6, jointly form N-type multiple tube with Q1, Q2.
The grid of described Q5, Q6 connects respectively described control signal output pin: K1_, K2_; Source ground; Drain electrode connects respectively a wherein link of described divider resistance R6, R7.
As shown in Figure 2, in certain embodiments, described output identification control unit also comprises a Voltage stabilizing module, and described Voltage stabilizing module sends to described kernel control module for the high ripple current of unstable voltage being converted to the low ripple electric current of burning voltage.
As shown in Figure 3, described Voltage stabilizing module U2 can be: various linear voltage stabilization LDO or three terminal regulator, as HT7550, ST7805, LM7805 etc., the preferred HT7550 of this specific embodiment integrated regulator U2, described integrated circuit U2 pin 1 is current input terminal, and meets filter capacitor C1; Pin 2 ground connection; Pin 3 is current output terminal, and output termination filter capacitor C2.
As shown in Figure 2, in certain embodiments, described output identification control unit also comprises a division module, and described division module is for carrying out dividing potential drop to being carried in the voltage of described exchange conversion unit, and while preventing exchange conversion cell conduction, voltage is excessive is burned.
As shown in Figure 3, be a specific embodiment of division module, described division module comprises: first, second pull-up resistor R1, R2; First, second divider resistance R6, R7.
R1, R2 one end are connected on respectively the source electrode of Q1, Q2, and the other end is connected on respectively the grid of Q1, Q2; One end of R6, R7 joins with the grid of Q1, Q2 respectively, and the other end is connected on the source electrode of Q6, Q5.Its effect is to prevent that when Q6, Q7 conducting the grid of Q1, Q2 and source potential are divided to source voltage to be controlled in 12V, avoids burning out Q1, Q2.
As shown in Figure 2, in certain embodiments, described output identification control unit also comprises that one for representing the state indicating module of the operating state of described output identification control unit.
As shown in Figure 3, described state indicating module is controlled by described control module.Described state indicating module can comprise indicator light, indicating bell etc.Described indicator light or indicating bell can be one or two, as described in Figure 3, described indicator light is two, described two indicator light LED1, LED2 one end ground connection, one end connects described output identification control unit by resistance R 4, R5 respectively, and described two LED1, LED2 are respectively used to display control module and control described exchange conversion unit output AC electricity and galvanic different conditions.
As shown in Figure 3, described kernel control module can be single-chip microcomputer U1, for example: and 51 serial 14 single-chip microcomputers, for simplified electrical circuit diagram, useless pin is unlisted, only draw power pins, GND pin, I/O port (O/pin/K1_/K2_/K3/K4), AD port (FB pin).Described this single-chip microcomputer belongs to prior art, does not repeat them here, and each pin connection of described single-chip microcomputer is as follows:
VCC pin: described VCC pin connects the output of described pressurizer U2, the electric current with burning voltage transmitting for receiving described pressurizer U2, to start integral control circuit U1.
The pin that C2 is directly moved to U1 in schematic diagram is in order to instruct PCB engineer, and this electric capacity must be connected on the place, nearest pin position of U1, electric capacity can not be arranged at a distance and connect with line.
I/O port, specifically comprises as follows:
K1_, K2_, K1, K2 pin, wherein K1_, K2_ and K3, K4 swing to; Described four pins are controlled 4 field effect transistor Q1, Q2 of described exchange conversion unit, the control signal of Q3, Q4 for exporting.
2 O/ pins: connect described LED1, LED2 by described resistance R 4, R5, control the light on and off of LED1, LED2.
Owing to adopting single-chip microcomputer to control as kernel control module, therefore very convenient to the change of function, only need slightly do to change and just can accomplish output overcurrent protection, for example, by the length of the overcurrent time above R3, judge whether it is that output is moderate.If converted to, exchange after-current still over upper threshold values, can carry out output power-off protection.
AD port (FB pin): connect described sampling resistor R3, receive the sampled signal of described sampling resistor R3 feedback.FB pin is provided with detection threshold, when sample rate current is less than threshold value, controls K1_, K4 output low level, and K2_, K3 export high level, at this moment Q2, Q3 conducting, Q1, Q4 cut-off, output direct current; When obtaining the sample rate current of sampling, be greater than threshold value and control K1_, K4 and K2_, K3 output alternating signal, thus Q2, Q3 and Q1, Q4 alternate conduction, and output AC is electric.
Preferably, for effectively avoiding output state change frequently back and forth under critical phenomena, upper and lower two threshold values can be set, be window phase in the middle of two values.When output becomes after alternating current, the voltage of sampling module reduces at once, but because having set a lower threshold value, once upper threshold value reaches " B state ", electric current must drop to lower threshold value just can convert A condition to, and lower threshold value is very low, and object just automatically converts direct current output state to after disconnecting in load, even if so the voltage drop of at this moment sampling module sampling, to normal value, still can keep alternating current output.
Preferably, described FB pin also connects a filter capacitor C3.
As shown in Figure 3, described sampling module is a sampling resistor R3, and described resistance R 3 one links connect respectively the Voltage Feedback input FB pin of described control module and the source electrode of field effect transistor Q3, Q4; Other end ground connection.
This embodiment is output as specific embodiment with the square wave of inverter, and in fact the present invention, except being applied to the inverter of square wave output, can also directly applying to and control the inverter of revising ripple or sinewave output etc.
The course of work is as follows:
After powering on, single-chip microcomputer U1 enters initialization.After initialization finishes, K1_, K4 output low level, K2_, K3 export high level, at this moment Q2, Q3 conducting, Q1, Q4 cut-off, electric current flows to b through a, and maintains this state always, establishes this state for " A condition ".
When access load be the Switching Power Supply load shown in accompanying drawing 8 (such as: printer), because circuit working is under normal condition, electric current is below the threshold range of FB pin, and circuit state still maintains " A condition ";
The load of supposing access is Industrial Frequency Transformer load as shown in Figure 7, because Industrial Frequency Transformer is to direct current no resistance almost, be equivalent to the direct short-circuit of 220V input, electric current is very large, at this moment more than the voltage above R3 is increased to upper threshold value immediately, FB pin receives after this signal, control the output state (at the preferred 50Hz of the control signal of exporting described in this specific embodiment) that pin K1_, K4 and K2_, K3 convert alternation to, now, Q2, Q3 and Q1, Q4 alternate conduction, output becomes alternating current, establishes this state for " B state ".
When output becomes after alternating current, voltage on R3 reduces at once, but because having set a lower threshold value, once upper threshold value reaches " B state ", electric current must drop to lower threshold value just can convert A condition to, and lower threshold value is very low, object just automatically converts direct current output state to after disconnecting in load, even so at this moment the upper voltage drop of R3 is to normal value, the output of U1 is still constant, keeps the output of alternating current.
Embodiment bis-,
The present invention also provides a kind of inverter with the output identification control unit as described in embodiment mono-, and described output identification control unit, referring to described in specific embodiment one, does not repeat them here.
Embodiment tri-,
The present invention also provides a kind of system with the inverter of the output identification control unit as described in embodiment mono-, and described output identification control unit, referring to described in specific embodiment one, does not repeat them here.
Described system can be for to noise jamming and the system of having relatively high expectations, such as Medical Devices.On existing Medical Devices, need configure printer, because printer is office appliances, can not cross medical safety, need to be just its power supply by inverter, Medical Devices are very responsive to disturbing, and adopt after the present invention, because existing printer 98% is all Switching Power Supply power supply (only needing powered by direct current), therefore inverter of the present invention only need to be exported direct current under it exports the control of identification control unit, thereby solves interference problem.
Embodiment tetra-,
The present invention also introduces a kind of control method of output identification control unit of the inverter as described in above-described embodiment, and in described method, partial content is described by previous embodiment, does not repeat them here.Described method comprises the steps:
S201, obtains sample rate current;
Sampling module obtains sample rate current and sends to kernel control module.
S202, kernel control module, by the described sample rate current threshold default with it, when sample rate current is greater than predetermined threshold value, sends control signal and controls exchange conversion unit output AC electricity; When sample rate current is less than predetermined threshold value, send control signal and control exchange conversion unit output direct current.
Preferably, described threshold value comprises upper threshold value and lower threshold value, and centre is the empty window phase.
As Fig. 6 shows, method for a better understanding of the present invention, further describes with more detailed embodiment below.
S301, system completes initialization
S302, sampling module obtains the FB pin that sample rate current sends to kernel control module.
S303, the sample rate current receiving according to the FB pin of kernel control module is compared with the preset value of this pin; When being less than lower threshold value, carry out S304 and control K1_, K4 output low level, K2_, K3 export high level; When being greater than upper threshold value, carry out S305 and control K1_, K4 and K2_, K3 output alternating signal; When between upper threshold value and lower threshold value, carry out S306 hold mode constant.
Further, described step S304 can also comprise that controlling LED1 lights; Described step S305 can also comprise that controlling LED2 lights.
S307, after constant time lag, repeated execution of steps S302-S306.
Described constant time lag can, for rational random time, be preferably 30mm at this specific embodiment.
Above the output identification control unit of a kind of inverter provided by the present invention and inverter thereof, system, control method are described in detail, for one of ordinary skill in the art, thought according to the embodiment of the present invention, all will change in specific embodiments and applications, therefore, this description should not be construed as limitation of the present invention.