Charging control circuit and household charging pile

Abstract

The utility model discloses a charging control circuit and a household charging pile, and relates to the technical field of charging piles. The household charging pile comprises a commercial power live wire access end, a commercial power null line access end and a charging gun. The charging control circuit comprises a main control circuit; the live wire switch circuit is used for connecting or disconnecting a path between the commercial power live wire access end and the charging gun according to the switch control signal output by the main control circuit; the null line switching circuit is used for switching on or switching off a path between the mains supply null line access end and the charging gun according to the switching control signal output by the main control circuit; the current detection circuit is used for detecting the input current of the charging gun and outputting a current detection signal to the main control circuit; the temperature detection circuit is used for detecting the working temperature of the charging gun and outputting a temperature detection signal to the main control circuit; wherein the main control circuit is used for outputting a switch control signal according to a current detection signal and / or a temperature detection signal. The utility model aims to improve the charging convenience of the electric automobile.

Description

Technical Field

[0001] The utility model relates to the technical field of charging piles, and in particular to a charging control circuit and a household charging pile. Background Art

[0002] With the advent of the new energy wave, electric vehicles have become a hot emerging force, but with the increase in the popularity of electric vehicles, various constraints have also been exposed, one of which is the charging problem. Compared with traditional fuel vehicles, electric vehicles have a shorter range, so the popularity and coverage of charging facilities are relatively high. At present, the commonly used charging facilities are mainly large charging stations, outdoor charging piles, community charging piles, and public parking lot charging piles. However, traditional charging piles have the disadvantages of difficult installation and transformation, low coverage, fixed location, high pressure on the power grid, and long waiting time for public charging piles, which makes it difficult to meet the growing charging needs of electric vehicles. Utility Model Content

[0003] The main purpose of the utility model is to provide a charging control circuit, aiming to improve the convenience of charging an electric vehicle.

[0004] To achieve the above purpose, the charging control circuit proposed by the utility model is applied to a home charging pile, wherein the home charging pile includes a mains live wire access terminal, a mains neutral wire access terminal and a charging gun, and the charging control circuit includes:

[0005] Main control circuit;

[0006] A live wire switch circuit, wherein the input end of the live wire switch circuit is electrically connected to the mains live wire access end, the output end of the live wire switch circuit is electrically connected to the charging gun, and the controlled end of the live wire switch circuit is electrically connected to the main control circuit, and the live wire switch circuit is used to turn on or off the path between the mains live wire access end and the charging gun according to the switch control signal output by the main control circuit;

[0007] A neutral line switch circuit, wherein the input end of the neutral line switch circuit is electrically connected to the mains neutral line access end, the output end of the neutral line switch circuit is electrically connected to the charging gun, the controlled end of the neutral line switch circuit is electrically connected to the main control circuit, and the neutral line switch circuit is used to turn on or off the path between the mains neutral line access end and the charging gun according to a switch control signal output by the main control circuit;

[0008] A current detection circuit, wherein an output end of the current detection circuit is electrically connected to the main control circuit, and the current detection circuit is used to detect an input current of the charging gun and output a current detection signal to the main control circuit;

[0009] A temperature detection circuit, wherein an output end of the temperature detection circuit is electrically connected to the main control circuit, and the temperature detection circuit is used to detect the operating temperature of the charging gun and output a temperature detection signal to the main control circuit;

[0010] Wherein, the main control circuit is used to output a switch control signal according to the current detection signal and / or the temperature detection signal.

[0011] In one embodiment, the live wire switch circuit comprises:

[0012] A first switch circuit, wherein an input end of the first switch circuit is electrically connected to a DC input end, and the first switch circuit is used to open or close a path between a mains live wire and a charging gun;

[0013] a second switch circuit, wherein a controlled end of the second switch circuit is electrically connected to the main control circuit, and the second switch circuit is used to open or close a path between the first switch circuit and a ground end;

[0014] When the second switch circuit is turned on, the first switch circuit is also in the on state.

[0015] In one embodiment, the live wire switch circuit includes a first resistor, a second resistor, a third resistor, a first capacitor, a first diode, a first relay, and a first switch tube;

[0016] Among them, the first end of the first resistor is electrically connected to the DC input end and the first end of the first capacitor, and the second end is electrically connected to the first end of the first relay, the second end of the first capacitor, and the cathode of the first diode; the second end of the first relay is electrically connected to the anode of the first diode and the first end of the first switch tube; the controlled end of the first switch tube is electrically connected to the second end of the second resistor and the first end of the third resistor, and the second end of the first switch tube is electrically connected to the second end of the third resistor and grounded; the first end of the second resistor is electrically connected to the output end of the main control circuit; the third end of the first relay is electrically connected to the output end of the AC live wire, and the fourth end of the first relay is electrically connected to the input end of the charging gun.

[0017] In one embodiment, the neutral line switch circuit comprises:

[0018] A third switch circuit, wherein an input end of the third switch circuit is electrically connected to the DC input end, and the third switch circuit is used to open or close a path between the mains neutral line and the charging gun;

[0019] a fourth switch circuit, wherein a controlled end of the fourth switch circuit is electrically connected to the main control circuit, and the fourth switch circuit is used to open or close a path between the fourth switch circuit and a ground end;

[0020] Wherein, when the fourth switch circuit is turned on, the third switch circuit is also in the turned-on state.

[0021] In one embodiment, the live wire switch circuit includes a fourth resistor, a fifth resistor, a sixth resistor, a second capacitor, a second diode, a second relay, and a second switch tube;

[0022] Among them, the first end of the fourth resistor is electrically connected to the DC input end and the first end of the second capacitor, and the second end is electrically connected to the first end of the second relay, the second end of the second capacitor, and the cathode of the second diode; the second end of the second relay is electrically connected to the anode of the second diode and the first end of the second switch tube; the controlled end of the second switch tube is electrically connected to the second end of the fifth resistor and the first end of the sixth resistor, and the second end of the second switch tube is electrically connected to the second end of the sixth resistor and grounded; the first end of the fifth resistor is electrically connected to the output end of the main control circuit; the third end of the second relay is electrically connected to the output end of the AC power live wire, and the fourth end of the second relay is electrically connected to the input end of the charging gun.

[0023] In one embodiment, the charging control circuit further includes a power supply circuit, an input end of the power supply circuit is electrically connected to an AC input end, and the power supply circuit is used to convert an input AC voltage into a DC voltage and output it.

[0024] In one embodiment, the power supply circuit comprises:

[0025] a protection circuit, wherein an input terminal of the protection circuit is electrically connected to the AC input terminal, and the protection circuit is used to limit the input current to below a first current and output the current;

[0026] A voltage conversion circuit, the input end of the voltage conversion circuit is electrically connected to the output end of the protection circuit, and the voltage conversion circuit is used to reduce the input AC voltage and then output it;

[0027] A rectifier circuit, the input end of which is electrically connected to the output end of the voltage conversion circuit, and the rectifier circuit is used to convert the reduced input AC voltage into a DC voltage and output it;

[0028] A voltage stabilizing circuit, wherein the input end of the voltage stabilizing circuit is electrically connected to the output end of the rectifier circuit, and the voltage stabilizing circuit is used to stabilize the input DC voltage at a preset voltage value and output it.

[0029] In one embodiment, the protection circuit includes: a fuse, a first varistor, a second varistor, a third varistor, a bidirectional TVS tube, and a seventh resistor;

[0030] Wherein, the first end of the fuse is electrically connected to the AC input end, the second end of the fuse is electrically connected to the first end of the first varistor, the first end of the third varistor, and the first end of the seventh resistor; the second end of the second varistor is electrically connected to the second end of the third varistor and the first end of the bidirectional TVS tube; the second end of the bidirectional TVS tube is connected to the ground end;

[0031] The voltage conversion circuit comprises: a third capacitor, an eighth resistor, a ninth resistor, and a transformer;

[0032] Among them, the first end of the third capacitor is electrically connected to the second end of the seventh resistor, the first end of the eighth resistor, and the first end of the first coil of the transformer; the second end of the third capacitor is electrically connected to the AC input end and the first end of the second coil of the transformer; the second end of the eighth resistor is electrically connected to the second end of the first coil of the transformer; and the second end of the ninth resistor is electrically connected to the second end of the second coil of the transformer.

[0033] In one embodiment, the rectifier circuit includes: a fourth capacitor, a fifth capacitor, a sixth capacitor, a first inductor, a second inductor, and a rectifier chip;

[0034] Among them, the first end of the first inductor is electrically connected to the second end of the eighth resistor, the second end of the second inductor is electrically connected to the AC input terminal and the second pin of the rectifier chip; the first end of the fourth capacitor is electrically connected to the DC input terminal and the third pin of the rectifier chip, the second end of the fourth capacitor is electrically connected to the first end of the fifth capacitor and the fourth pin of the rectifier chip; the second end of the fifth capacitor is electrically connected to the fifth pin of the rectifier chip, the second end of the sixth capacitor, and the ground terminal; the first end of the sixth capacitor is electrically connected to the first end of the second inductor and the sixth pin of the rectifier chip; the first pin of the rectifier chip is electrically connected to the second end of the ninth resistor, and the seventh pin of the rectifier chip is electrically connected to the output terminal;

[0035] The voltage stabilizing circuit comprises: a seventh capacitor, an eighth capacitor, and a voltage stabilizing diode;

[0036] Among them, the first end of the seventh capacitor is electrically connected to the second end of the second inductor, the cathode of the Zener diode, the first end of the eighth capacitor, and the output end, and the second end of the seventh capacitor is electrically connected to the second end of the fifth capacitor, the anode of the Zener diode, the second end of the eighth capacitor, and the ground end.

[0037] The utility model also provides a household charging pile, which comprises a charging control circuit as described in any one of the above items.

[0038] The technical solution of the utility model is applied to a home charging pile by adopting a charging control circuit. Among them, the home charging pile includes a mains live wire access terminal, a mains neutral wire access terminal and a charging gun; the charging control circuit includes a main control circuit, a live wire switch circuit, a neutral wire switch circuit, a current detection circuit, and a temperature detection circuit. The main control circuit can judge the input temperature detection signal, current detection signal or communication signal, and then output a switch control signal to the live wire switch circuit and the neutral wire switch circuit, thereby turning on or off the path between the mains live wire access, the neutral wire switch circuit and the charging gun, so as to achieve the technical effect of charging electric vehicles through the mains. Users can directly charge electric vehicles by connecting to the home mains through a home charging pile equipped with a charging control circuit, which alleviates the charging pressure of public charging piles, solves the emergency needs of users for charging electric vehicles, and improves the convenience of charging electric vehicles. In addition, the charging control circuit can judge whether the current power consumption is in a normal state through the current detection circuit and the temperature detection circuit, so as to improve the safety of emergency charging of electric vehicles using home mains. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0040] Figure 1 This is a module schematic diagram of the charging control circuit of the utility model;

[0041] Figure 2 This is a schematic diagram of the circuit structure of an embodiment of the charging control circuit of the utility model;

[0042] Figure 3 The figure is a circuit structure diagram of an embodiment of a charging control circuit of the utility model.

[0043] Description of Figure Numbers:

[0044] 10. Main control circuit; 20. Live wire switch circuit; 30. Neutral wire switch circuit; 40. Current detection circuit; 50. Temperature detection circuit; R1-R9, first resistor-ninth resistor; C1-C6, first capacitor-sixth capacitor; RV1-RV3, first varistor-third varistor; L1-L2, first inductor-second inductor.

[0045] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0047] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0048] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0049] With the advent of the new energy wave, electric vehicles have become a hot emerging force, but with the increase in the popularity of electric vehicles, various constraints have also been exposed, one of which is the charging problem. Compared with traditional fuel vehicles, electric vehicles have a shorter range, so the popularity and coverage of charging facilities are relatively high. At present, the commonly used charging facilities are mainly large charging stations, outdoor charging piles, community charging piles, and public parking lot charging piles. However, traditional charging piles have the disadvantages of difficult installation and transformation, low coverage, fixed location, high pressure on the power grid, and long waiting time for public charging piles, which makes it difficult to meet the growing charging needs of electric vehicles.

[0050] Therefore, reference Figure 1 to Figure 2 The utility model proposes a charging control circuit, which is applied to a household charging pile. The household charging pile includes a mains live wire access terminal, a mains neutral wire access terminal and a charging gun. The charging control circuit includes:

[0051] Main control circuit 10;

[0052] A live wire switch circuit 20, wherein the input end of the live wire switch circuit 20 is electrically connected to the mains live wire access end, the output end of the live wire switch circuit 20 is electrically connected to the charging gun, and the controlled end of the live wire switch circuit 20 is electrically connected to the main control circuit 10, and the live wire switch circuit 20 is used to turn on or off the path between the mains live wire access end and the charging gun according to the switch control signal output by the main control circuit 10;

[0053] A neutral line switch circuit 30, wherein the input end of the neutral line switch circuit 30 is electrically connected to the mains neutral line access end, the output end of the neutral line switch circuit 30 is electrically connected to the charging gun, and the controlled end of the neutral line switch circuit 30 is electrically connected to the main control circuit 10, and the neutral line switch circuit 30 is used to turn on or off the path between the mains neutral line access end and the charging gun according to the switch control signal output by the main control circuit 10;

[0054] A current detection circuit 40, wherein an output end of the current detection circuit 40 is electrically connected to the main control circuit 10, and the current detection circuit 40 is used to detect an input current of the charging gun and output a current detection signal to the main control circuit 10;

[0055] A temperature detection circuit 50, wherein the output end of the temperature detection circuit 50 is electrically connected to the main control circuit 10, and the temperature detection circuit 50 is used to detect the operating temperature of the charging gun and output a temperature detection signal to the main control circuit 10;

[0056] The main control circuit 10 is used to output a switch control signal according to the current detection signal and / or the temperature detection signal.

[0057] In this embodiment, the main control circuit 10 can be implemented by a main controller, such as FPGA (Field Programmable Gate Array), MCU (Microcontroller Unit), DSP (Digital Signal Process), SOC (System On Chip), etc. The main control circuit 10 is mainly responsible for coordinating and controlling the data collection, processing, decision-making and response of the actuator of each circuit in the charging control circuit.

[0058] In this embodiment, the live wire switch circuit 20 includes:

[0059] A first switch circuit, wherein an input end of the first switch circuit is electrically connected to a DC input end, and the first switch circuit is used to open or close a path between a mains live wire and a charging gun;

[0060] a second switch circuit, wherein a controlled end of the second switch circuit is electrically connected to the main control circuit 10, and the second switch circuit is used to open or close a path between the first switch circuit and a ground end;

[0061] When the second switch circuit is turned on, the first switch circuit is also in the on state.

[0062] Furthermore, the live wire switch circuit 20 includes a first resistor R1, a second resistor R2, a third resistor R3, a first capacitor C1, a first diode, a first relay, and a first switch tube;

[0063] Among them, the first end of the first resistor R1 is electrically connected to the DC input end and the first end of the first capacitor C1, and the second end is electrically connected to the first end of the first relay, the second end of the first capacitor C1, and the cathode of the first diode; the second end of the first relay is electrically connected to the anode of the first diode and the first end of the first switch tube; the controlled end of the first switch tube is electrically connected to the second end of the second resistor R2 and the first end of the third resistor R3, and the second end of the first switch tube is electrically connected to the second end of the third resistor R3 and grounded; the first end of the second resistor R2 is electrically connected to the output end of the main control circuit 10; the third end of the first relay is electrically connected to the output end of the AC live wire, and the fourth end of the first relay is electrically connected to the input end of the charging gun.

[0064] It should be understood that the basic working principle of the relay is to use the electromagnetic principle to generate a magnetic field through the current in the coil. This magnetic field will attract a mechanical arm (or called a moving contact), thereby changing its position, and then closing or disconnecting the path between the mains live wire access terminal and the charging gun. In this process, the first switch circuit can activate the coil of the relay through a small current control circuit, and the relay itself can control a load with a larger current or higher voltage, that is, 220V mains. Among them, the first switch tube in the second switch circuit can be implemented by, for example, a MOS tube, an IGBT tube, a thyristor, a triode, a power tube, etc. In this embodiment, the first switch tube is an NPN triode, which receives the switch control signal output by the main control circuit 10 and then conducts the path between the first switch circuit and the ground terminal, so that the relay is closed, and the technical effect of conducting the path between the mains live wire access terminal and the charging gun is achieved.

[0065] In this embodiment, the neutral line switch circuit 30 includes:

[0066] A third switch circuit, wherein the input end of the third switch circuit is electrically connected to the DC input end, and the third switch circuit is used to open or close the path between the mains neutral line access end and the charging gun;

[0067] a fourth switch circuit, wherein a controlled end of the fourth switch circuit is electrically connected to the main control circuit 10, and the fourth switch circuit is used to open or close a path between the fourth switch circuit and a ground end;

[0068] Wherein, when the fourth switch circuit is turned on, the third switch circuit is also in the turned-on state.

[0069] Furthermore, the live wire switch circuit 20 includes a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a second capacitor C2, a second diode, a second relay, and a second switch tube;

[0070] Among them, the first end of the fourth resistor R4 is electrically connected to the DC input end and the first end of the second capacitor C2, and the second end is electrically connected to the first end of the second relay, the second end of the second capacitor C2, and the cathode of the second diode; the second end of the second relay is electrically connected to the anode of the second diode and the first end of the second switch tube; the controlled end of the second switch tube is electrically connected to the second end of the fifth resistor R5 and the first end of the sixth resistor R6, and the second end of the second switch tube is electrically connected to the second end of the sixth resistor R6 and grounded; the first end of the fifth resistor R5 is electrically connected to the output end of the main control circuit 10; the third end of the second relay is electrically connected to the output end of the AC power live wire, and the fourth end of the second relay is electrically connected to the input end of the charging gun.

[0071] In this embodiment, the working principle of the neutral line switch circuit 30 is consistent with the working principle of the live line switch circuit 20. Therefore, it is not repeated. Among them, the switch control signal received by the neutral line switch circuit 30 and the live line switch circuit 20 from the main control circuit 10 is the same. Therefore, the on or off state of the neutral line switch circuit 30 and the live line switch circuit 20 is the same.

[0072] In this embodiment, the current detection circuit 40 can be implemented by using sensors such as a resistor shunt, a Hall current sensor, a Rogowski coil current sensor, a fluxgate current sensor, and an optical fiber current sensor. Among them, the Hall current sensor is taken as an example. The Hall current sensor is arranged near the output circuit of the charging gun. When current passes through the conductor, a magnetic field is generated around the conductor. The Hall element is located in this magnetic field. When current flows through the conductor, the magnetic field passes through the Hall element, causing the carriers inside the Hall element to be offset under the action of the Lorentz force, and a voltage difference is generated in the vertical direction of the element, namely the Hall voltage. The weak voltage signal generated by the Hall element is processed by a built-in signal conditioning circuit (such as an amplifier, a linearization circuit, etc.), converted into a standard voltage or current signal, or directly converted into a digital signal and input to the main control circuit 10, so that the main control circuit 10 performs related actions according to the input current detection signal.

[0073] In this embodiment, the temperature detection circuit 50 can be implemented by a detection circuit based on a thermistor, such as a resistor divider circuit based on an NTC resistor or an NTC probe, or a resistor divider circuit based on a PTC resistor or a PTC probe. Optionally, the temperature detection circuit 50 can also be implemented by a temperature sensor, such as an infrared temperature sensor, a thermocouple temperature sensor, etc. Among them, there can be multiple temperature detection circuits 50, and multiple temperature detection circuits 50 can be arranged at different positions in the charging gun. The main control circuit 10 can determine multiple temperature values ​​based on multiple temperature detection signals, and calculate the actual ambient temperature through a preset temperature algorithm, such as an average value, a weighted calculation, etc., so as to improve the accuracy of the detection of the ambient temperature of the charging gun.

[0074] In this embodiment, the main control circuit 10 can judge the input temperature detection signal, current detection signal or communication signal, and then output the switch control signal to the live wire switch circuit 20 and the neutral wire switch circuit 30, so as to open or close the access to the live wire of the mains power, the path between the neutral wire switch circuit 30 and the charging gun, so as to achieve the technical effect of charging the electric vehicle through the mains. Users can directly charge the electric vehicle by connecting to the home mains through the home charging pile equipped with a charging control circuit, which alleviates the charging pressure of the public charging pile, solves the emergency demand of the user's electric vehicle charging, and improves the convenience of charging the electric vehicle. In addition, the charging control circuit can judge whether the current power consumption is in a normal state through the current detection circuit 40 and the temperature detection circuit 50, so as to improve the safety of the electric vehicle using the home mains for emergency charging.

[0075] refer to Figure 3 In one embodiment of the utility model, the charging control circuit also includes a power supply circuit, the input end of the power supply circuit is electrically connected to the AC input end, and the power supply circuit is used to convert the input AC voltage into a DC voltage and output it.

[0076] In this embodiment, the power supply circuit includes:

[0077] a protection circuit, wherein an input terminal of the protection circuit is electrically connected to the AC input terminal, and the protection circuit is used to limit the input current to below a first current and output the current;

[0078] A voltage conversion circuit, the input end of the voltage conversion circuit is electrically connected to the output end of the protection circuit, and the voltage conversion circuit is used to reduce the input AC voltage and then output it;

[0079] A rectifier circuit, the input end of which is electrically connected to the output end of the voltage conversion circuit, and the rectifier circuit is used to convert the reduced input AC voltage into a DC voltage and output it;

[0080] A voltage stabilizing circuit, wherein the input end of the voltage stabilizing circuit is electrically connected to the output end of the rectifier circuit, and the voltage stabilizing circuit is used to stabilize the input DC voltage at a preset voltage value and output it.

[0081] Furthermore, the protection circuit includes: a fuse, a first varistor RV1, a second varistor RV2, a third varistor RV3, a bidirectional TVS tube, and a seventh resistor R7;

[0082] Wherein, the first end of the fuse is electrically connected to the AC input end, the second end of the fuse is electrically connected to the first end of the first varistor RV1, the first end of the third varistor RV3, and the first end of the seventh resistor R7; the second end of the second varistor RV2 is electrically connected to the second end of the third varistor RV3 and the first end of the bidirectional TVS tube; the second end of the bidirectional TVS tube is connected to the ground end;

[0083] The voltage conversion circuit includes: a third capacitor C3, an eighth resistor R8, a ninth resistor R9, and a transformer;

[0084] Among them, the first end of the third capacitor C3 is electrically connected to the second end of the seventh resistor R7, the first end of the eighth resistor R8, and the first end of the first coil of the transformer; the second end of the third capacitor C3 is electrically connected to the AC input end and the first end of the second coil of the transformer; the second end of the eighth resistor R8 is electrically connected to the second end of the first coil of the transformer; the second end of the ninth resistor R9 is electrically connected to the second end of the second coil of the transformer.

[0085] The rectifier circuit includes: a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a first inductor L1, a second inductor L2, and a rectifier chip;

[0086] Wherein, the first end of the first inductor L1 is electrically connected to the second end of the eighth resistor R8, the second end of the second inductor L2 is electrically connected to the AC input end and the second pin of the rectifier chip; the first end of the fourth capacitor C4 is electrically connected to the DC input end and the third pin of the rectifier chip, the second end of the fourth capacitor C4 is electrically connected to the first end of the fifth capacitor C5 and the fourth pin of the rectifier chip; the second end of the fifth capacitor C5 is electrically connected to the fifth pin of the rectifier chip, the second end of the sixth capacitor C6, and the ground terminal; the first end of the sixth capacitor C6 is electrically connected to the first end of the second inductor L2 and the sixth pin of the rectifier chip; the first pin of the rectifier chip is electrically connected to the second end of the ninth resistor R9, and the seventh pin of the rectifier chip is electrically connected to the output end;

[0087] The voltage stabilizing circuit comprises: a seventh capacitor, an eighth capacitor, and a voltage stabilizing diode;

[0088] Among them, the first end of the seventh capacitor is electrically connected to the second end of the second inductor L2, the cathode of the Zener diode, the first end of the eighth capacitor, and the output end, and the second end of the seventh capacitor is electrically connected to the second end of the fifth capacitor C5, the anode of the Zener diode, the second end of the eighth capacitor, and the ground end.

[0089] In this embodiment, the power supply circuit is used to convert the input 220V AC power into 12V DC power to power the relays in the live switch circuit 20 and the neutral switch circuit 30. It can be understood that the power supply circuit 20 uses a fuse to prevent the large current caused by short circuit from damaging the circuit, that is, overcurrent protection. The sensitive components in the circuit are protected from damage by overvoltage transient events by using varistor and bidirectional TVS tube. Specifically, a varistor is a resistor with nonlinear voltage-current characteristics, usually made of metal oxide material. Under normal operating voltage, the resistance value of the varistor is very high and almost non-conductive; but when the voltage in the circuit exceeds a certain threshold, its resistance value drops rapidly, allowing a large amount of current to pass, thereby clamping the overvoltage at a safe level to protect the subsequent circuit. The bidirectional TVS tube is an overvoltage protection device in the form of a diode, which can protect the circuit in two directions. It works based on the avalanche breakdown principle of the PN junction. When the voltage at both ends exceeds the rated value, it quickly changes to a low resistance state and clamps the voltage at a predetermined value, thereby protecting the circuit. When used together, varistors and bidirectional TVS tubes can form complementary technical effects to provide more comprehensive and effective circuit protection. This combination takes advantage of the respective advantages of both to cope with transient voltage events of different characteristics and intensities. Among them, varistors are usually used as the first level of protection, placed close to the power inlet, to absorb and discharge excessive energy surges, such as lightning strikes or large voltage spikes on the power line. Because it can withstand large energy shocks, it is suitable for handling high-energy events, but the response speed is relatively slow and may age over time. Bidirectional TVS tubes are used as the second or final level of protection, close to the protected sensitive circuits or components, mainly to deal with fast transient voltage and electrostatic discharge events. TVS tubes have a fast response speed, can respond quickly and clamp voltage, and protect precision electronic equipment from damage. Although the current capacity is relatively small, it has a good inhibitory effect on high-frequency or rapidly changing voltage spikes. Through this hierarchical configuration, the varistor can first absorb most of the energy, reduce the pressure on the TVS tube, and extend the service life of the TVS tube and other post-stage protection components. At the same time, the TVS tube ensures that even after the varistor responds, the circuit is still carefully protected to prevent any residual overvoltage from damaging sensitive components. Through the appropriate setting of the protection circuit, protection effects such as overcurrent, overvoltage, and leakage are achieved.

[0090] Furthermore, the input AC power is stepped down and converted into a lower AC voltage by using a transformer, and the input AC voltage is converted into a DC voltage and output by a rectifier chip. Specifically, the input 220V AC voltage is output as a 12V DC voltage through the transformer and the rectifier chip, and then passes through the filter circuit and the voltage stabilizing circuit, so that the power supply circuit 20 outputs a stable 12V DC voltage.

[0091] The utility model also proposes a home charging pile, which includes a charging control circuit as described in any one of the above. It is worth noting that since the home charging pile of the utility model is based on the above charging control circuit, the embodiment of the home charging pile of the utility model includes all technical solutions of all embodiments of the above charging control circuit, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0092] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A charging control circuit, applied to a home charging pile, characterized in that: The home charging pile includes a mains live wire access terminal, a mains neutral wire access terminal and a charging gun, and the charging control circuit includes: Main control circuit; A live wire switch circuit, wherein the input end of the live wire switch circuit is electrically connected to the mains live wire access end, the output end of the live wire switch circuit is electrically connected to the charging gun, and the controlled end of the live wire switch circuit is electrically connected to the main control circuit, and the live wire switch circuit is used to turn on or off the path between the mains live wire access end and the charging gun according to the switch control signal output by the main control circuit; A neutral line switch circuit, wherein the input end of the neutral line switch circuit is electrically connected to the mains neutral line access end, the output end of the neutral line switch circuit is electrically connected to the charging gun, the controlled end of the neutral line switch circuit is electrically connected to the main control circuit, and the neutral line switch circuit is used to turn on or off the path between the mains neutral line access end and the charging gun according to a switch control signal output by the main control circuit; A current detection circuit, wherein an output end of the current detection circuit is electrically connected to the main control circuit, and the current detection circuit is used to detect an input current of the charging gun and output a current detection signal to the main control circuit; A temperature detection circuit, wherein an output end of the temperature detection circuit is electrically connected to the main control circuit, and the temperature detection circuit is used to detect the operating temperature of the charging gun and output a temperature detection signal to the main control circuit; Wherein, the main control circuit is used to output a switch control signal according to the current detection signal and / or the temperature detection signal.

2. The charging control circuit according to claim 1, characterized in that: The live wire switch circuit comprises: A first switch circuit, wherein an input end of the first switch circuit is electrically connected to a DC input end, and the first switch circuit is used to open or close a path between a mains live wire access end and a charging gun; a second switch circuit, wherein a controlled end of the second switch circuit is electrically connected to the main control circuit, and the second switch circuit is used to open or close a path between the first switch circuit and a ground end; When the second switch circuit is turned on, the first switch circuit is also in the on state.

3. The charging control circuit according to claim 2, characterized in that: The live wire switch circuit includes a first resistor, a second resistor, a third resistor, a first capacitor, a first diode, a first relay, and a first switch tube; Among them, the first end of the first resistor is electrically connected to the DC input end and the first end of the first capacitor, and the second end is electrically connected to the first end of the first relay, the second end of the first capacitor, and the cathode of the first diode; the second end of the first relay is electrically connected to the anode of the first diode and the first end of the first switch tube; the controlled end of the first switch tube is electrically connected to the second end of the second resistor and the first end of the third resistor, and the second end of the first switch tube is electrically connected to the second end of the third resistor and grounded; the first end of the second resistor is electrically connected to the output end of the main control circuit; the third end of the first relay is electrically connected to the output end of the AC live wire, and the fourth end of the first relay is electrically connected to the input end of the charging gun.

4. The charging control circuit according to claim 1, characterized in that: The neutral line switch circuit comprises: A third switch circuit, wherein the input end of the third switch circuit is electrically connected to the DC input end, and the third switch circuit is used to open or close the path between the mains neutral line access end and the charging gun; a fourth switch circuit, wherein a controlled end of the fourth switch circuit is electrically connected to the main control circuit, and the fourth switch circuit is used to open or close a path between the fourth switch circuit and a ground end; Wherein, when the fourth switch circuit is turned on, the third switch circuit is also in the on state.

5. The charging control circuit according to claim 4, characterized in that: The live wire switch circuit includes a fourth resistor, a fifth resistor, a sixth resistor, a second capacitor, a second diode, a second relay, and a second switch tube; Among them, the first end of the fourth resistor is electrically connected to the DC input end and the first end of the second capacitor, and the second end is electrically connected to the first end of the second relay, the second end of the second capacitor, and the cathode of the second diode; the second end of the second relay is electrically connected to the anode of the second diode and the first end of the second switch tube; the controlled end of the second switch tube is electrically connected to the second end of the fifth resistor and the first end of the sixth resistor, and the second end of the second switch tube is electrically connected to the second end of the sixth resistor and grounded; the first end of the fifth resistor is electrically connected to the output end of the main control circuit; the third end of the second relay is electrically connected to the output end of the AC power live wire, and the fourth end of the second relay is electrically connected to the input end of the charging gun.

6. The charging control circuit according to claim 1, characterized in that: The charging control circuit also includes a power supply circuit, an input end of the power supply circuit is electrically connected to the AC input end, and the power supply circuit is used to convert the input AC voltage into a DC voltage and output it.

7. The charging control circuit according to claim 6, characterized in that: The power supply circuit comprises: a protection circuit, wherein an input terminal of the protection circuit is electrically connected to the AC input terminal, and the protection circuit is used to limit the input current to below a first current and output the current; A voltage conversion circuit, the input end of the voltage conversion circuit is electrically connected to the output end of the protection circuit, and the voltage conversion circuit is used to reduce the input AC voltage and then output it; A rectifier circuit, the input end of which is electrically connected to the output end of the voltage conversion circuit, and the rectifier circuit is used to convert the reduced input AC voltage into a DC voltage and output it; A voltage stabilizing circuit, wherein the input end of the voltage stabilizing circuit is electrically connected to the output end of the rectifier circuit, and the voltage stabilizing circuit is used to stabilize the input DC voltage at a preset voltage value and output it.

8. The charging control circuit according to claim 7, characterized in that: The protection circuit includes: a fuse, a first varistor, a second varistor, a third varistor, a bidirectional TVS tube, and a seventh resistor; Wherein, the first end of the fuse is electrically connected to the AC input end, the second end of the fuse is electrically connected to the first end of the first varistor, the first end of the third varistor, and the first end of the seventh resistor; the second end of the second varistor is electrically connected to the second end of the third varistor and the first end of the bidirectional TVS tube; the second end of the bidirectional TVS tube is connected to the ground end; The voltage conversion circuit comprises: a third capacitor, an eighth resistor, a ninth resistor, and a transformer; Among them, the first end of the third capacitor is electrically connected to the second end of the seventh resistor, the first end of the eighth resistor, and the first end of the first coil of the transformer; the second end of the third capacitor is electrically connected to the AC input end and the first end of the second coil of the transformer; the second end of the eighth resistor is electrically connected to the second end of the first coil of the transformer; and the second end of the ninth resistor is electrically connected to the second end of the second coil of the transformer.

9. The charging control circuit according to claim 8, characterized in that: The rectifier circuit includes: a fourth capacitor, a fifth capacitor, a sixth capacitor, a first inductor, a second inductor, and a rectifier chip; Among them, the first end of the first inductor is electrically connected to the second end of the eighth resistor, the second end of the second inductor is electrically connected to the AC input terminal and the second pin of the rectifier chip; the first end of the fourth capacitor is electrically connected to the DC input terminal and the third pin of the rectifier chip, the second end of the fourth capacitor is electrically connected to the first end of the fifth capacitor and the fourth pin of the rectifier chip; the second end of the fifth capacitor is electrically connected to the fifth pin of the rectifier chip, the second end of the sixth capacitor, and the ground terminal; the first end of the sixth capacitor is electrically connected to the first end of the second inductor and the sixth pin of the rectifier chip; the first pin of the rectifier chip is electrically connected to the second end of the ninth resistor, and the seventh pin of the rectifier chip is electrically connected to the output terminal; The voltage stabilizing circuit comprises: a seventh capacitor, an eighth capacitor, and a voltage stabilizing diode; Among them, the first end of the seventh capacitor is electrically connected to the second end of the second inductor, the cathode of the Zener diode, the first end of the eighth capacitor, and the output end, and the second end of the seventh capacitor is electrically connected to the second end of the fifth capacitor, the anode of the Zener diode, the second end of the eighth capacitor, and the ground end.

10. A home charging pile, characterized in that: The home charging pile comprises a charging control circuit as described in any one of claims 1-9.

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