CN208782579U - A kind of start and stop circuit - Google Patents

Abstract

The utility model discloses a kind of start and stop circuits, including Schmidt trigger U2, U6 and U7 and door U3 and U4, d type flip flop U5, diode D7, resistance R2, capacitor C2, wherein, the 1st pin of d type flip flop U5 is connected with the output end of Schmidt trigger U7；The input terminal of Schmidt trigger U7 is connected with one end of the cathode of diode D7, one end of capacitor C2, resistance R2；Capacitor C2 other end ground connection；The 2nd pin of d type flip flop U5 is grounded；The output end of Schmidt trigger U2 is connected with the first pin with door U3；The 4th pin of d type flip flop U5 is connected with the output end of the anode of diode D7, the other end of resistance R2, Schmidt trigger U6；The 5th pin of d type flip flop U5 is connected with the 2nd pin of door U3, with the 2nd pin of door U4.The start and stop circuit of the utility model uses a series of logical devices, may be implemented accurately to control, while also further reducing costs.

Description

A kind of start and stop circuit

Technical field

The utility model relates to wireless charging field more particularly to a kind of start and stop electricity for wireless charging control Road.

Background technique

Wireless charging technology, i.e. Wireless charging technology refer to using electromagnetic induction principle, are filling Energy transmission is carried out by magnetic field between electric appliance and power device, without using electric lead, is derived from wireless power transmission technology, Three kinds are broadly divided into according to transmission principle: electromagnetic induction manifold type wireless charging technology, magnet coupled resonant type wireless charging technique With microwave radiation formula wireless charging technology.Magnet coupled resonant type wireless charging technique is on the basis of electromagnetic induction manifold type principle On joined the principle of resonance, i.e. energy can efficiently be transmitted between two objects with identical resonance frequency. It is similar with electromagnetic induction manifold type wireless power transmission mode on the composition of circuit, is all to pass through the direct current after rectification High-frequency inversion is converted to high-frequency alternating current, and receiving coil receives after high-frequency alternating current through over commutation circuit and DC transfer circuit To power supply for electrical equipment.The difference is that being added to resonant capacitance on transmitting coil and receiving coil, passes through and change resonant capacitance Value makes system reach resonant state, to realize wireless power transmission.

The prior art, powerful wireless charging device such as electric car wireless charging is not perfect, still there is many ask Topic urgently studies function.Currently, it by DC inverter is exchange that general high-power wireless charging, which is all using full bridge inverter, Electricity supply wireless transmission coil, the working condition of full-bridge affect the transmission performance of whole system, current most control plan It is slightly all to be controlled using control chip the work of full-bridge, but this mode is difficult to make full-bridge work in Sofe Switch shape State, to influence transmission performance.

Therefore in view of the drawbacks of the prior art, it is really necessary to propose a kind of technical solution to solve skill of the existing technology Art problem.

Utility model content

In view of this, it is necessory to provide a kind of start and stop circuit for wireless charging control, using logic device The high-power wireless charging of part control, accurately controls wireless charging so as to stabilization.

In order to solve technical problem of the existing technology, the technical solution of the utility model is as follows:

A kind of start and stop circuit, the start and stop circuit realized using logical device, for according to clipping and The output signal of zero cross detection circuit, current foldback circuit and arc-suppression circuit controls driving circuit；

The start and stop circuit include Schmidt trigger U2, U6 and U7, with door U3 and U4, d type flip flop U5, Diode D7, resistance R2, capacitor C2, wherein the 1st pin of d type flip flop U5 is connected with the output end of Schmidt trigger U7；It applies The input terminal of schmitt trigger U7 is connected with one end of the cathode of diode D7, one end of capacitor C2, resistance R2；Capacitor C2 is another End ground connection；The 2nd pin of d type flip flop U5 is grounded；The 3rd pin of d type flip flop U5 and the letter for passing through clipping and zero cross detection circuit Number, the input terminal of Schmidt trigger U2, be connected with the 1st pin of door U4；The output end of Schmidt trigger U2 with door U3 The first pin be connected；The 4th pin and the anode of diode D7, the other end of resistance R2, Schmidt trigger of d type flip flop U5 The output end of U6 is connected；The 5th pin of d type flip flop U5 is connected with the 2nd pin of door U3, with the 2nd pin of door U4；With door U3 Driving circuit is connect with the output end of door U4；The 6th pin floating of d type flip flop U5；Described Schmidt trigger U2, the U6 Model with U7 is 74HC14；With door U3 and U4 model 74HC08, d type flip flop model 74HC74.

Compared with prior art, the start and stop circuit of the utility model uses a series of logical devices, Ke Yishi Now accurate control, while also further reducing costs, be conducive to the marketing of wireless charging technology.

Detailed description of the invention

Fig. 1 is the functional block diagram of the control circuit of the utility model application.

Fig. 2 is the circuit diagram of clipping and zero cross detection circuit in the utility model.

Fig. 3 is the circuit diagram of start and stop circuit in the utility model.

Fig. 4 is the circuit diagram of current foldback circuit in the utility model.

Fig. 5 is the circuit diagram of arc-suppression circuit in the utility model.

Following specific embodiment will further illustrate the utility model in conjunction with above-mentioned attached drawing.

Specific embodiment

Technical solution provided by the utility model is described further below with reference to attached drawing.

Referring to Fig. 1, it show the functional block diagram of control circuit provided by the utility model, including clipping and zero passage detection electricity Road, start and stop circuit, current foldback circuit and arc-suppression circuit, the current foldback circuit and clipping and zero cross detection circuit It is connected with feedback signal；The start and stop circuit is realized using logical device, for being examined according to the clipping and zero passage The output signal of slowdown monitoring circuit, current foldback circuit and arc-suppression circuit controls the driving circuit；Current foldback circuit, amplitude limiter circuit The feedback signal from primary coil is received with zero passage detection, and is connect with arc-suppression circuit by a series of logical devices, it is defeated Signal out guarantees full-bridge work in Sofe Switch state by the work of full-bridge of start and stop circuit control.

Referring to fig. 2, it is shown the circuit diagram of clipping and zero cross detection circuit, is intercepted just using signal feedback mutual inductor Feedback signal on grade coil has obtained a voltage raising, electric current reduces, exchange of the frequency equal to coil resonance frequency is believed Number, which has just obtained an ac square wave identical with resonance frequency by amplitude limiter circuit and zero cross detection circuit, then passes through Overdrive circuit amplification, for driving full-bridge to work, just completes self-excitation.Specifically include diode D1~D6, capacitor C1, resistance R1, Schmidt trigger U1, wherein the cathode of first diode D1 and the cathode of third diode D3, one end phase of capacitor C1 Company is connected with feedback signal jointly；The anode of first diode D1 is connected with the anode of the second diode D2；Third diode The anode of D3 is connected with the anode of the 4th diode D4；The cathode of the cathode of second diode D2 and the 4th diode D4, the 6th The cathode of diode D6, the 2nd pin of Schmidt trigger U1 are connected and are grounded；The other end of capacitor C1 and one end of resistance R1 It is connected；The cathode of the other end of capacitor R1 and the 5th diode D5, the anode of the 6th diode D6, Schmidt trigger U1 3 pins are connected；The anode of 5th diode is connected with the 1st pin of Schmidt trigger U1 and connects+5V power supply；Schmidt's touching 4th pin of hair device is connected to the input terminal of start and stop circuit；Described diode D1, the D4 is Schottky diode；Two Pole pipe D2, D3 is zener diode；Diode D5, D6 are switching diode；Capacitor C1 is ceramic disc capacitor；Schmidt trigger U1 Model 74HC14.

Wherein, the voltage that can be born due to logic circuit is very low, so with two pole zener diode 1N4733 and Schottky The high-voltage signal fed back is limited in 5V or so, by coupled capacitor C1 using resistance R1 by pipe 1N5819 differential concatenation Signal is decayed, two 1N4148 is again passed by and clipping is carried out to signal, be then passed through zero passage detection Schmidt trigger, will hand over The sine wave of stream is changed into square wave.The square-wave signal of self-excitation is thus obtained.

Referring to Fig. 3, it show the circuit diagram of the utility model start and stop circuit, including Schmidt trigger U2, U6 and U7 and door U3 and U4, d type flip flop U5, diode D7, resistance R2, capacitor C2, wherein draw the 1st of d type flip flop U5 Foot is connected with the output end of Schmidt trigger U7；The input terminal of Schmidt trigger U7 and cathode, the capacitor C2 of diode D7 One end, resistance R2 one end be connected；Capacitor C2 other end ground connection；The 2nd pin of d type flip flop U5 is grounded；The of d type flip flop U5 3 pins and the input terminal of signal, Schmidt trigger U2 by clipping and zero cross detection circuit and the 1st pin phase of door U4 Even；The output end of Schmidt trigger U2 is connected with the first pin with door U3；The 4th pin and diode D7 of d type flip flop U5 Anode, the other end of resistance R2, Schmidt trigger U6 output end be connected；The 5th pin of d type flip flop U5 with door U3's 2nd pin is connected with the 2nd pin of door U4；Driving circuit is connect with door U3 and with the output end of door U4；The of d type flip flop U5 6 pin floating；The model of described Schmidt trigger U2, U6 and U7 are 74HC14；With door U3 and U4 model 74HC08, D Trigger model 74HC74；

Wherein, feedback signal after clipping and zero passage detection is sent into start and stop circuit, is coupled with and door The end CLK of 74HC08 and d type flip flop 74HC74.Using two and door, a signal connect after reversed, the purpose is to regardless of There is any situation in other parts, and two are impossible to open simultaneously with door.Core device of the 74HC74 as control signal conduction Part, CD and SD pin connect the output signal of arc extinguishing and overcurrent protection, and output end Q is connected to two another pins with door, with warp Feedback signal phase and as a result feeding drive amplification circuit control full-bridge work after crossing clipping and zero passage detection.74HC74's is true It is worth table are as follows:

1 74HC74 truth table of table

When the input terminal of U6 is high level, it is sent into the end SD by U6 reverse phase,For low level, after U7 reverse phase It is sent into the end CD,For high level, output is just high level signal, opens full-bridge by drive amplification circuit；When the input of U6 When end becomes low level, U6 output is high level, and is charged by R2 to C2, since capacitor both end voltage cannot be mutated, so The input terminal or low level of U7, in this wayWithIt is all high level, it is defeated when resonance signal is to be in low level It is still high level out, continues to complete self-excitation, when resonance signal becomes high level from low level, output is just low level, entirely Bridge will end, and ensure that full-bridge work in the state of Sofe Switch in this way.

Referring to fig. 4, it is shown the circuit diagram of current foldback circuit, its purpose is that protecting the power device of full-bridge not It is burned, the automatic protection circuit when resonance current is excessive.Specifically include diode D8~D11, capacitor C3~C6, resistance R3~ R5, capacitor C3~C6, variable resistance VR1, voltage comparator U9；The 1st pin and the 4th pin, capacitor C6 of voltage comparator U9 One end, one end of resistance R3, one end of capacitor C3, diode D9 be connected and be grounded with the cathode of D11；The sun of diode D9 Pole is connected with one end of the cathode of diode D8, feedback signal；The anode of diode D11 and cathode, the feedback of diode D10 The other end of signal is connected；2nd pin is connected with one end of the sliding end of variable resistance VR1, capacitor C5；The other end of capacitor C5 It is connected and is grounded with one end of one end of variable resistance VR1, capacitor C4；The other end of variable resistance VR1 and one end of resistance R4 It is connected；3rd pin is connected with the anode of the other end of resistance R3, the other end of capacitor C3, diode D8 and D10；5th pin and 6th pin is connected；7th pin is connected with one end of the other end of capacitor C6, resistance R5；Another termination+5V electricity of resistance R5 Source；8th pin is connected with the other end of the other end capacitor C4 of resistance R4 and connects+9V power supply；The voltage comparator U9 Model LM311；

Wherein, mutual inductor is truncated to the AC signal of high pressure low current from resonant tank, by rectifying and wave-filtering and value electricity Resistance is followed by the "-" end of voltage comparator LM311, compared with the voltage at "+" end, when "+" end voltage is greater than "-" end voltage When, voltage comparator exports high level, on the contrary then export low level.The output of LM311 terminates to the CD of another 74HC74 End.When resonance current is excessively high, voltage comparator exports low level, makes driving output be low level, full-bridge by trigger Switching tube cut-off.

Since system works in resonant state, electric current can constantly rise, and need to be switched off to a certain extent in electric current rising Circuit, with protective switch pipe, this just needs arc extinguishing control circuit to complete.Arc extinguishing controller can generate a positive pulsewidth and frequency Adjustable square wave goes to open and close driving.When square wave is to high level, driving is opened, and gives IGBT gate driving letter Number, electric current rises in resonance circuit；When square wave is low level, driving cut-off, full-bridge circuit does not work, the electricity in resonance circuit Stream will slowly lower.When adjusting slide rheostat increases positive pulsewidth, the time of full-bridge work will be elongated, gives just The energy of grade resonant tank is just more, and the electric current in primary resonant circuit is bigger, and resonance potential is also higher, and power will become larger.When When adjusting slide rheostat increases square wave frequency, the working frequency of full-bridge can also be got higher, and the efficiency of system will increase.

Referring to Fig. 5, it show the circuit diagram of arc-suppression circuit, including 555 chip U10 and U11, resistance R6~R14, electricity Hold C7~C14, diode D12~D14, slide rheostat VR2 and VR3, optical fiber head U12 and U13, Schmidt trigger U14, and Door U15, d type flip flop U16；The 1st pin of 555 chip U10 is connected and is grounded with the 7th pin；2nd pin and the 6th pin, capacitor C7, one end of resistance R6 are connected；One end of another termination slide rheostat VR2 of resistance R6；The other end of capacitor C7 is grounded；The 3 pins are connected with one end of the other end of slide rheostat VR2, capacitor C10；4th pin and the 7th resistance R7, the 12nd pole The anode of pipe, one end of the 8th resistance, the 8th pin of 555 chip U11, one end of slide rheostat VR3 are connected；5th pin with One end of 8th capacitor C8 is connected；The other end of 8th capacitor C8 is grounded；8th pin is connected with one end of the 9th capacitor C9；The The other end of nine capacitor C9 is grounded；The 1st pin of 555 chip U11 is grounded；The other end of 2nd pin and the tenth capacitor C10, The other end of seven resistance R7, the other end of the 12nd diode D12 are connected；One end of 3rd pin and the tenth resistance R10, the tenth One end of one resistance R11 is connected；4th pin connects the other end of the 8th resistance R8；One end of 5th pin and the 12nd capacitor C12 It is connected；The other end of 12nd capacitor C12 is grounded；6th pin and the 7th pin, one end of the 9th resistance R9, the 13rd capacitor One end of C13 is connected；The other end of 9th resistance R9 is connected with the other end of slide rheostat VR3；8th pin and the 11st electricity The one end for holding C11 is connected；The other end of 11st capacitor C11 is grounded；The 2nd pin and the 6th pin, the 7th of optical fiber head U12 is drawn Foot, the other end of eleventh resistor R11 are connected；3rd pin ground connection；The 2nd pin of optical fiber head U13 and the 6th pin, the 12nd electricity One end of one end, the 14th capacitor C14 for hindering R12 is connected；The other end of 14th capacitor C14 is grounded；3rd pin and the 12nd The other end of resistance R12, the input terminal of Schmidt trigger U14, the anode of the 14th diode D14 are connected；14th pole The cathode of pipe D14 connects one end of thirteenth resistor R13；Another termination+5V power supply of thirteenth resistor R13；7th pin ground connection； The output end of Schmidt trigger U14 is connected with the 3rd pin of the 1st pin of door U15, d type flip flop U16；With the of door U15 2 pins are connected with the 5th pin of d type flip flop U16；The 1st pin floating of d type flip flop U16；2nd pin is connected simultaneously with the 4th pin Connect+5V power supply；6th pin meets the 14th resistance R14；The other end of 14th resistance R14 is grounded；The diode D13 with D14 is light emitting diode.

Arc extinguishing control circuit is substantially the multivibrator being composed of two 555 timers, first 555 The second pin exported as second 555 inputs, and can change the frequency of output signal by adjusting slide rheostat VR2 Rate, slide rheostat VR3 control the pulsewidth of output signal, to control the work of whole system.Arc extinguishing output uses optical fiber Connection, its purpose is to avoid the interference of high frequency magnetic field, while optical fiber has very high transmission speed, may be implemented more accurate Ground control.

Since optical fiber output is that low level is effective, in order to restore waveform, a reverser is terminated in output, after reverse phase Signal simultaneously be connected to 74HC74 the end CLK and in door.When system power is in normal range (NR), voltage comparator LM311 is exported For high level, thenFor high level,Power end is connect, is always high level, when arc extinguishing signal becomes high level from low level When, U10 output is high level, then U9 output is also high level, and full-bridge is opened at this time；It is U10 when arc extinguishing signal becomes low level Output is still high level, and U9 output is low level, and full-bridge ends at this time.When system power is excessive, voltage comparator output For low level, then U10 output is also low level, and U9 output is also low level, full-bridge cut-off.

The method and its core concept of the above embodiments are only used to help understand the utility model.It should refer to It out, for those skilled in the art, without departing from the principle of this utility model, can also be to this Some improvement and modification can also be carried out for utility model, these improvement and modification also fall into the protection scope of the utility model claims It is interior.

The foregoing description of the disclosed embodiments can be realized professional and technical personnel in the field or using originally practical new Type.Various modifications to these embodiments will be readily apparent to those skilled in the art, and determine herein The General Principle of justice can be realized in other embodiments without departing from the spirit or scope of the present utility model.Cause This, the present invention will not be limited to the embodiments shown herein, and is to fit to and principles disclosed herein The widest scope consistent with features of novelty.

Claims (1)

1. a kind of start and stop circuit, which is characterized in that the start and stop circuit is realized using logical device, is used for root Driving circuit is controlled according to the output signal of clipping and zero cross detection circuit, current foldback circuit and arc-suppression circuit；

The start and stop circuit includes Schmidt trigger U2, U6 and U7 and door U3 and U4, d type flip flop U5, diode D7, resistance R2, capacitor C2, wherein the 1st pin of d type flip flop U5 is connected with the output end of Schmidt trigger U7；Schmidt's touching The input terminal of hair device U7 is connected with one end of the cathode of diode D7, one end of capacitor C2, resistance R2；Another termination of capacitor C2 Ground；The 2nd pin of d type flip flop U5 is grounded；The 3rd pin of d type flip flop U5 with by clipping and zero cross detection circuit signal, apply The input terminal of schmitt trigger U2 is connected with the 1st pin of door U4；The output end of Schmidt trigger U2 and first with door U3 Pin is connected；The 4th pin of d type flip flop U5 and the anode of diode D7, the other end of resistance R2, Schmidt trigger U6 it is defeated Outlet is connected；The 5th pin of d type flip flop U5 is connected with the 2nd pin of door U3, with the 2nd pin of door U4；With door U3 and with door The output end of U4 connects driving circuit；The 6th pin floating of d type flip flop U5；The type of described Schmidt trigger U2, U6 and U7 It number is 74HC14；With door U3 and U4 model 74HC08, d type flip flop model 74HC74.