Protection circuit of direct current charging pile

Abstract

The utility model discloses a protection circuit of a direct current charging pile, which relates to the technical field of direct current charging piles, and comprises a power supply module used for carrying out electric energy conversion processing on accessed alternating current electric energy; the electric energy transmission module is used for transmitting the electric energy to the electric vehicle connected with the charging gun module and performing power-off protection; the short-circuit detection module is used for short-circuit detection; the state detection module is used for controlling the power-off of the electric energy transmission module and detecting the state of the short circuit when the short circuit occurs; the timing module is used for controlling the state detection module to reset when the disappearance time of the short circuit exceeds the set timing time; and the protection control module is used for stopping the self-recovery control work of the state detection module when the short circuit state is detected for the third time. The protection circuit of the direct-current charging pile can provide high-precision direct-current electric energy, perform short-circuit protection and power-off self-recovery control, avoid frequent power-off protection, prolong the service life of the direct-current charging pile and further improve safety.

Description

TECHNICAL FIELD

[0001] The utility model relates to direct current charging pile technical field, specifically a protection circuit of direct current charging pile. BACKGROUND

[0002] Direct current charging pile, a kind of charging equipment specially providing direct current for electric vehicle, can be converted into direct current suitable for the battery charging of electric vehicle by the mains (alternating current), to directly power supply to the battery of electric vehicle, direct current charging pile in prior art will carry out short circuit detection to charging gun, and when short circuit occurs, power-off protection is carried out, after short-circuit fault disappears, power-on control is carried out again, but during short-circuit protection, because of the disappearance of short-circuit state, direct current charging pile carries out power supply again, if short-circuit hidden danger at charging gun is not eliminated at this time, it will lead to the frequent power-on and power-off work of direct current charging pile, reduce the service life of direct current charging pile and there is certain security risk, therefore, there is to be improved. UTILITY MODEL CONTENT

[0003] The utility model embodiment provides a protection circuit of direct current charging pile to solve the problems in the above background art.

[0004] To achieve the above object, the utility model provides the following technical scheme:

[0005] A kind of protection circuit of direct current charging pile, it include: power module, electric energy transmission module, short circuit detection module, charging gun module, state detection module, timing module and protection control module;

[0006] Power module is used to connect alternating current energy, carries out rectification, inverter and isolation voltage transformation processing to alternating current energy and exports first electric energy, carries out rectification filter processing to first electric energy and exports second electric energy;

[0007] Electric energy transmission module is connected with the power module, charging gun module and state detection module, for transmitting second electric energy to charging gun module, when receiving the first protection signal exported by state detection module, stop transmitting second electric energy;

[0008] Short circuit detection module is connected with the power module, for voltage sampling to second electric energy and outputting first control signal when the signal sampled is greater than set short-circuit threshold;

[0009] Charging gun module is used to receive second electric energy and power supply for connected electric vehicle;

[0010] The state detection module is connected with the short circuit detection module and the timing module, and is configured to perform self-locking processing on the first control signal and output a first protection signal when the first control signal is received, output a second control signal when the first protection signal is output and the first control signal is not received, and stop outputting the first protection signal when a first reset signal output by the timing module is received.

[0011] The timing module is connected with the protection control module, and is configured to set a timing time, output a first reset signal when a time length of the second control signal received exceeds the timing time, and stop outputting the first reset signal when a second protection signal output by the protection control module is received.

[0012] The protection control module is configured to receive the first reset signal, perform counting processing on the first reset signal, and output a second protection signal when the first reset signal is received for the third time.

[0013] As a further scheme of the utility model: the power module includes power interface, voltage conversion device, first rectifier, first inductance and first capacitor, the electric energy transmission module includes first power tube, first resistance and first switch tube, the charging gun module includes charging gun interface,

[0014] Preferably, the first end and the second end of the power interface are connected with the first end and the second end of the voltage conversion device respectively, the third end and the fourth end of the voltage conversion device are connected with the first end and the second end of the first rectifier respectively, the third end of the first rectifier is connected with the first end of the first capacitor, one end of the first resistance and the drain of the first power tube through the first inductance, the source of the first power tube is connected with the first end of the charging gun interface, the gate of the first power tube is connected with the other end of the first resistance and the collector of the first switch tube, the base of the first switch tube is connected with the state detection module, and the emitter of the first switch tube is connected with the second end of the first capacitor, the fourth end of the first rectifier, the second end of the charging gun interface and the ground end.

[0015] As a further scheme of the utility model: the short circuit detection module includes second resistance, third resistance, first potentiometer and first diode,

[0016] Preferably, one end of the second resistance is connected with the first end of the first capacitor, the other end of the second resistance is connected with one end of the first potentiometer and the slide end and connected with the fourth end of the first rectifier through the third resistance, the other end of the first potentiometer is connected with the cathode of the first diode, and the anode of the first diode is connected with the state detection module.

[0017] As a further scheme of the utility model: the state detection module includes second diode, third diode, first power supply, fourth resistance, first logic chip, first inverter, third switch tube and second logic chip,

[0018] Preferably, the anode of the second diode is connected with the anode of the first diode and the input end of the first inverter, the cathode of the second diode is connected with the cathode of the third diode and the A end of the first logic chip, the B end of the first logic chip is connected with the collector of the third switch tube and the first power supply through the fourth resistance, the anode of the third diode is connected with the Y end of the first logic chip, the A end of the second logic chip and the base of the first switch tube, the B end of the second logic chip is connected with the output end of the first inverter, the Y end of the second logic chip and the base of the third switch tube are connected with the timing module, and the emitter of the third switch tube is grounded.

[0019] As a further scheme of the utility model: the timing module includes a third power supply, a fourth switch tube, a second switch tube, a fifth resistance, a sixth resistance, a second capacitor, a seventh resistance and a fifth switch tube;

[0020] Preferably, the collector of the fourth switch tube is connected with the collector of the second switch tube, one end of the second switch tube is connected with one end of the fifth resistance and one end of the second capacitor and is connected with the base of the fourth switch tube through the sixth resistance, the base of the second switch tube is connected with the Y end of the second logic chip, one end of the seventh resistance is connected with the collector of the fifth switch tube and the base of the third switch tube, the other end of the seventh resistance is connected with the emitter of the fifth switch tube, the other end of the second capacitor, the other end of the fifth resistance and the ground end, and the base of the fifth switch tube is connected with the protection control module.

[0021] As a further scheme of the utility model: the protection control module includes a third capacitor, an eighth resistance, a ninth resistance, a first counter and a second power supply;

[0022] Preferably, the sixteenth end of the first counter is connected with the second power supply and is connected with the fifteenth end of the first counter and one end of the eighth resistance through the third capacitor, the other end of the eighth resistance is connected with the thirteenth end of the first counter, the eighth end of the first counter and the ground end, the first end of the first counter is connected with the base of the fifth switch tube through the ninth resistance, and the fourteenth end of the first counter is connected with the emitter of the fourth switch tube.

[0023] Compared with the prior art, the direct current charging pile protection circuit has the advantages that the power module can perform input rectification, inversion, voltage transformation and output rectification filtering processing, so as to provide high-precision direct current power, and the power transmission module transmits the power to the charging gun module, meanwhile, the short circuit detection module detects the power output by the power module, when short circuit occurs, the state detection module controls the power transmission module to perform power-off protection, the safety of the charging pile is improved, meanwhile, when the state detection module does not detect short circuit within the timing time set by the timing module, the power transmission module is controlled to be powered again, meanwhile, when the protection control module detects short circuit for the third time, the self-recovery power supply work is stopped, frequent power-off protection is avoided, the service life of the direct current charging pile is prolonged and the safety is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed to be used in the description of the embodiments of the present application will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor.

[0025] Figure 1 A principle block diagram of a protection circuit of a direct current charging pile is provided for the embodiments of the present application.

[0026] Figure 2 A circuit diagram of a protection circuit of a direct current charging pile is provided for the embodiments of the present application.

[0027] Figure 3 A connection circuit diagram of a protection control module is provided for the embodiments of the present application. DETAILED DESCRIPTION

[0028] The technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the present application.

[0029] In one embodiment, please refer to Figure 1 A protection circuit of a direct current charging pile, comprising: a power module 1, a power transmission module 2, a short circuit detection module 3, a charging gun module 4, a state detection module 5, a timing module 6 and a protection control module 7.

[0030] Specifically, the power module 1 is configured to access AC power, rectify, invert and isolate and transform the AC power and output first power, and rectify and filter the first power and output second power;

[0031] The power transmission module 2 is connected with the power module 1, the charging gun module 4 and the state detection module 5, configured to transmit the second power to the charging gun module 4 and stop transmitting the second power when receiving the first protection signal output by the state detection module 5;

[0032] The short circuit detection module 3 is connected with the power module 1, configured to sample the voltage of the second power and output a first control signal when the sampled signal is greater than a set short circuit threshold;

[0033] The charging gun module 4 is configured to receive the second power and supply power to the connected electric vehicle;

[0034] The state detection module 5 is connected with the short circuit detection module 3 and the timing module 6, configured to perform self-locking processing on the first control signal and output a first protection signal when receiving the first control signal, output a second control signal when the first protection signal is output and the first control signal is not received, and stop outputting the first protection signal when receiving a first reset signal output by the timing module 6;

[0035] The timing module 6 is connected with the protection control module 7, configured to set a timing time, output a first reset signal when the duration of the received second control signal exceeds the timing time, and stop outputting the first reset signal when receiving a second protection signal output by the protection control module 7;

[0036] The protection control module 7 is configured to receive the first reset signal and perform counting processing on the first reset signal, and output a second protection signal when the first reset signal is received for the third time.

[0037] In specific embodiments, the power module 1 described above can adopt a power circuit composed of a power interface, a voltage conversion device, a rectifier, etc., can access alternating current energy and perform input rectification, inversion, isolation voltage conversion, output rectification and filtering processing on the alternating current energy, and then provide direct current energy; the power transmission module 2 described above can adopt a power transmission circuit composed of field effect tubes, resistors, triodes, etc., to perform power transmission control and power-off protection control; the short circuit detection module 3 described above can adopt a short circuit detection circuit composed of resistors, potentiometers and diodes, which can sample voltage and detect the voltage size of the sampled signal and the set short circuit threshold value; the charging gun module 4 described above can adopt a charging gun circuit composed of a charging gun interface, which is connected with an electric vehicle; the state detection module 5 described above can adopt a state detection circuit composed of logic chips, diodes, inverters, etc., which can perform high-level self-locking and self-locking output of a first protection signal when a short circuit occurs, so as to control the power transmission module 2 to power off, and output a signal in a high-level state, i.e., a second control signal, when a short circuit occurs and no short circuit occurs again; the timing module 6 described above can adopt a timing circuit composed of triodes, resistors, capacitors, etc., which can set a timing time, and start timing work when receiving the second control signal, and output a signal in a high-level state, i.e., a first reset signal, when the time length of receiving the second control signal exceeds the timing time; the protection control module 7 described above can adopt a protection control circuit composed of resistors, capacitors and counters, which can detect the number of times that the first reset signal output by the timing module 6, and then judge the number of times of short circuit self-recovery of the charging pile, and control the timing module 6 to stop outputting the first reset signal when the third short circuit self-recovery occurs.

[0038] In another embodiment, please refer to Figure 1 , Figure 2 and Figure 3 , the power module 1 includes a power interface, a voltage conversion device, a first rectifier T1, a first inductor L1 and a first capacitor C1; the power transmission module 2 includes a first power tube Q1, a first resistor R1 and a first switch tube V1; the charging gun module 4 includes a charging gun interface;

[0039] Specifically, the first end and the second end of the power interface are connected with the first end and the second end of the voltage conversion device respectively, the third end and the fourth end of the voltage conversion device are connected with the first end and the second end of the first rectifier T1 respectively, the third end of the first rectifier T1 is connected with the first end of the first capacitor C1, one end of the first resistor R1 and the drain of the first power tube Q1 through the first inductor L1, the source of the first power tube Q1 is connected with the first end of the charging gun interface, the gate of the first power tube Q1 is connected with the other end of the first resistor R1 and the collector of the first switch tube V1, the base of the first switch tube V1 is connected with the state detection module 5, and the emitter of the first switch tube V1 is connected with the second end of the first capacitor C1, the fourth end of the first rectifier T1, the second end of the charging gun interface and the ground end.

[0040] In specific embodiments, the voltage conversion device can be composed of a rectifier, a capacitor, an inverter and a transformer, and sequentially performs rectification, filtering, inversion and transformation; the first power tube Q1 can be an N-channel field effect tube; the first switch tube V1 can be an NPN triode.

[0041] Further, the short circuit detection module 3 comprises a second resistor R2, a third resistor R3, a first potentiometer RP1 and a first diode D1;

[0042] Specifically, one end of the second resistor R2 is connected to the first end of the first capacitor C1, the other end of the second resistor R2 is connected to one end of the first potentiometer RP1 and the wiper end and connected to the fourth end of the first rectifier T1 through the third resistor R3, the other end of the first potentiometer RP1 is connected to the cathode of the first diode D1, and the anode of the first diode D1 is connected to the state detection module 5.

[0043] In specific embodiments, the second resistor R2 and the third resistor R3 perform voltage sampling; the first potentiometer RP1 and the first diode D1 set the short circuit threshold.

[0044] Further, the state detection module 5 comprises a second diode D2, a third diode D3, a first power supply VCC1, a fourth resistor R4, a first logic chip J1, a first inverter INV1, a third switch tube V3 and a second logic chip J2;

[0045] Specifically, the anode of the second diode D2 is connected to the anode of the first diode D1 and the input end of the first inverter INV1, the cathode of the second diode D2 is connected to the cathode of the third diode D3 and the A end of the first logic chip J1, the B end of the first logic chip J1 is connected to the collector of the third switch tube V3 and connected to the first power supply VCC1 through the fourth resistor R4, the anode of the third diode D3 is connected to the Y end of the first logic chip J1, the A end of the second logic chip J2 and the base of the first switch tube V1, the B end of the second logic chip J2 is connected to the output end of the first inverter INV1, the Y end of the second logic chip J2 and the base of the third switch tube V3 are connected to the timing module 6, and the emitter of the third switch tube V3 is grounded.

[0046] In specific embodiments, the first logic chip J1 and the second logic chip J2 can both be selected as AND gate chips, wherein the first logic chip J1 cooperates with the fourth resistor R4, the first power supply VCC1, the second diode D2 and the third diode D3 to perform self-locking processing and is controlled by the third switch tube V3 to stop self-locking work, and the third switch tube V3 can be an NPN triode; the first inverter INV1 can be a NOT gate chip.

[0047] Further, the timing module 6 comprises a third power supply VCC3, a fourth switch tube V4, a second switch tube V2, a fifth resistor R5, a sixth resistor R6, a second capacitor C2, a seventh resistor R7 and a fifth switch tube V5.

[0048] Specifically, the third power supply VCC3 is connected to the collector of the fourth switch tube V4 and the collector of the second switch tube V2, the emitter of the second switch tube V2 is connected to one end of the fifth resistor R5 and one end of the second capacitor C2 and connected to the base of the fourth switch tube V4 through the sixth resistor R6, the base of the second switch tube V2 is connected to the Y terminal of the second logic chip J2, the emitter of the fourth switch tube V4 is connected to one end of the seventh resistor R7, the collector of the fifth switch tube V5 and the base of the third switch tube V3, the other end of the seventh resistor R7 is connected to the emitter of the fifth switch tube V5, the other end of the second capacitor C2, the other end of the fifth resistor R5 and the ground terminal, and the base of the fifth switch tube V5 is connected to the protection control module 7.

[0049] In specific embodiments, the fourth switch tube V4, the second switch tube V2 and the fifth switch tube V5 can be NPN type triodes, the second capacitor C2 can be an energy storage capacitor, and the maximum energy voltage that can be stored in the second capacitor C2 cooperates with the fifth resistor R5 and the seventh resistor R7 to trigger the fourth switch tube V4 to conduct for a timing time.

[0050] Further, the protection control module 7 comprises a third capacitor C3, an eighth resistor R8, a ninth resistor R9, a first counter IC1 and a second power supply VCC2.

[0051] Specifically, the sixteenth terminal of the first counter IC1 is connected to the second power supply VCC2 and connected to the fifteenth terminal of the first counter IC1 and one end of the eighth resistor R8 through the third capacitor C3, the other end of the eighth resistor R8 is connected to the thirteenth terminal of the first counter IC1, the eighth terminal of the first counter IC1 and the ground terminal, the first terminal of the first counter IC1 is connected to the base of the fifth switch tube V5 through the ninth resistor R9, and the fourteenth terminal of the first counter IC1 is connected to the emitter of the fourth switch tube V4.

[0052] In specific embodiments, the first counter IC1 can be a CD4017 counter.

[0053] In this embodiment of a protection circuit for a DC charging pile, AC power is input through a power interface. A voltage conversion device performs input rectification, filtering, inversion, and transformation processing on the AC power to output a first power. The first power is then rectified and filtered by a first rectifier T1, a first inductor L1, and a first capacitor C1 to output a second power. This second power is transmitted to the charging gun interface via a first power transistor Q1. Simultaneously, a second resistor R2 and a third resistor R3 sample the voltage of the second power. When the sampled signal exceeds the short-circuit threshold set by a first potentiometer RP1 and a first diode D1, the first diode D1 breaks down and outputs a first control signal. This causes the first logic chip J1 to self-lock in conjunction with the second diode D2, the third diode D3, the fourth resistor R4, and the first power supply VCC1, and output a first protection signal. This controls the first switching transistor V1 to turn on and the first power transistor Q1 to turn off. Simultaneously, after the short circuit disappears, the first inverter... INV1 will output a high level, causing the Y terminal of the second logic chip J2 to output a second control signal, controlling the second switch V2 to conduct. The second capacitor C2 stores energy. When the maximum stored energy, together with the fifth resistor R5 and the seventh resistor R7, triggers the fourth switch V4 to conduct, it indicates that the short circuit has disappeared for longer than the timing period. The fourth switch V4 provides a first reset signal, controlling the third switch V3 to conduct. The first logic chip J1 stops its self-locking operation, the first power transistor Q1 is turned on again, and at the same time, the fourteenth terminal of the first counter IC1 becomes high. The first counter IC1 starts counting. When the short circuit self-recovery occurs for the third time, that is, when the fourth switch V4 is turned on for the third time, the first terminal of the first counter IC1 will control the fifth switch V5 to conduct, so that the fourteenth terminal of the first counter IC1 remains low, controlling the third switch V3 to conduct, so that the short circuit self-recovery will not occur again when a short circuit occurs next time.

[0054] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0055] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A protection circuit of a direct current charging pile, characterized in that, the protection circuit of the direct current charging pile comprises a power supply module, an electric energy transmission module, a short circuit detection module, a charging gun module, a state detection module, a timing module and a protection control module; the power supply module is configured to access alternating current electric energy, rectify, invert and isolate and transform the alternating current electric energy, and output first electric energy, and rectify and filter the first electric energy and output second electric energy; the electric energy transmission module is connected with the power supply module, the charging gun module and the state detection module, and is configured to transmit the second electric energy to the charging gun module, and stop transmitting the second electric energy when a first protection signal output by the state detection module is received; the short circuit detection module is connected with the power supply module, and is configured to sample a voltage of the second electric energy, and output a first control signal when a sampled signal is greater than a set short circuit threshold; the charging gun module is configured to receive the second electric energy and supply power to a connected electric vehicle; the state detection module is connected with the short circuit detection module and the timing module, and is configured to perform self-locking processing on the first control signal and output the first protection signal when the first control signal is received, output a second control signal when the first protection signal is output and the first control signal is not received, and stop outputting the first protection signal when a first reset signal output by the timing module is received; the timing module is connected with the protection control module, and is configured to set a timing time, and output the first reset signal when a time length of the second control signal received exceeds the timing time, and stop outputting the first reset signal when a second protection signal output by the protection control module is received; the protection control module is configured to receive the first reset signal and perform counting processing on the first reset signal, and output the second protection signal when the first reset signal is received for the third time.

2. The protection circuit of a direct current charging pile according to claim 1, characterized in that, The power supply module comprises a power supply interface, a voltage conversion device, a first rectifier, a first inductor and a first capacitor; the electric energy transmission module comprises a first power tube, a first resistor and a first switch tube; and the charging gun module comprises a charging gun interface. A first end and a second end of the power supply interface are connected with a first end and a second end of the voltage conversion device, a third end and a fourth end of the voltage conversion device are connected with a first end and a second end of the first rectifier, a third end of the first rectifier is connected with a first end of the first capacitor, one end of the first resistor and a drain of the first power tube through the first inductor, a source of the first power tube is connected with a first end of the charging gun interface, a gate of the first power tube is connected with the other end of the first resistor and a collector of the first switch tube, a base of the first switch tube is connected with the state detection module, and an emitter of the first switch tube is connected with a second end of the first capacitor, a fourth end of the first rectifier, a second end of the charging gun interface and a ground end.

3. The protection circuit of a direct current charging pile according to claim 2, characterized in that, The short circuit detection module comprises a second resistor, a third resistor, a first potentiometer and a first diode. One end of the second resistor is connected with the first end of the first capacitor, the other end of the second resistor is connected with one end of the first potentiometer and the slide end and connected with the fourth end of the first rectifier through the third resistor, the other end of the first potentiometer is connected with the cathode of the first diode, and the anode of the first diode is connected with the state detection module.

4. The protection circuit of a direct current charging pile according to claim 3, characterized in that, The state detection module comprises a second diode, a third diode, a first power supply, a fourth resistor, a first logic chip, a first inverter, a third switch tube and a second logic chip. The anode of the second diode is connected with the anode of the first diode and the input end of the first inverter, the cathode of the second diode is connected with the cathode of the third diode and the A end of the first logic chip, the B end of the first logic chip is connected with the collector of the third switch tube and connected with the first power supply through the fourth resistor, the anode of the third diode is connected with the Y end of the first logic chip, the A end of the second logic chip and the base of the first switch tube, the B end of the second logic chip is connected with the output end of the first inverter, the Y end of the second logic chip and the base of the third switch tube are connected with the timing module, and the emitter of the third switch tube is grounded.

5. The protection circuit of a direct current charging pile according to claim 4, characterized in that, The timing module comprises a third power supply, a fourth switch tube, a second switch tube, a fifth resistor, a sixth resistor, a second capacitor, a seventh resistor and a fifth switch tube. The third power supply is connected with the collector of the fourth switch tube and the collector of the second switch tube, the emitter of the second switch tube is connected with one end of the fifth resistor and one end of the second capacitor and connected with the base of the fourth switch tube through the sixth resistor, the base of the second switch tube is connected with the Y end of the second logic chip, the emitter of the fourth switch tube is connected with one end of the seventh resistor, the collector of the fifth switch tube and the base of the third switch tube, the other end of the seventh resistor is connected with the emitter of the fifth switch tube, the other end of the second capacitor, the other end of the fifth resistor and the ground end, and the base of the fifth switch tube is connected with the protection control module.

6. The protection circuit of a direct current charging pile according to claim 5, characterized in that, The protection control module comprises a third capacitor, an eighth resistor, a ninth resistor, a first counter and a second power supply. The sixteenth end of the first counter is connected with the second power supply and connected with the fifteenth end of the first counter and one end of the eighth resistor through the third capacitor, the other end of the eighth resistor is connected with the thirteenth end of the first counter, the eighth end of the first counter and the ground end, the first end of the first counter is connected with the base of the fifth switch tube through the ninth resistor, and the fourteenth end of the first counter is connected with the emitter of the fourth switch tube.

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