CN114374254A

CN114374254A - Charging circuit and charging pile

Info

Publication number: CN114374254A
Application number: CN202110018203.3A
Authority: CN
Inventors: 陈建生; 姜振廷; 庞晋永; 刘亮
Original assignee: Huawei Digital Power Technologies Co Ltd
Current assignee: Huawei Digital Power Technologies Co Ltd
Priority date: 2021-01-07
Filing date: 2021-01-07
Publication date: 2022-04-19

Abstract

The charging circuit comprises a starting unit, an auxiliary power supply unit, a control unit and a power conversion unit, wherein the starting unit is used for controlling the charging circuit to enter a charging state according to an input first CAN signal; the control unit is used for controlling the charging circuit to enter a standby state according to the input second CAN signal, and the auxiliary power supply unit stops working in the standby state. The charging circuit can reduce the hardware cost and the standby power consumption of the charging circuit at the same time, and the method can be applied to the charging pile, so that the hardware cost and the standby power consumption of the charging pile are reduced, and signal interference is avoided.

Description

Charging circuit and charging pile

Technical Field

The application relates to the technical field of automobiles, in particular to a charging circuit and a charging pile.

Background

With the vigorous development of the electric automobile industry, the number of electric automobiles is increasing day by day. At present, the electric automobile is generally charged through the charging pile, so that the quantity of the charging pile needs to be increased to meet the charging requirement of the electric automobile. When charging pile is not connected with an electric automobile for charging, the charging pile is in a more energy-saving standby state. The standby power of the existing charging pile is relatively high, generally between dozens and hundreds of watts, and the cost of electric energy consumed during standby is still high. Therefore, it is necessary to reduce the standby power consumption of the charging pile to save the cost.

Disclosure of Invention

In view of this, a charging circuit and a charging pile are provided, the charging circuit of the embodiment of the application can simultaneously reduce the hardware cost and the standby power consumption of the charging circuit, and the method can be applied to the charging pile, so that the hardware cost and the standby power consumption of the charging pile are reduced, and signal interference is avoided.

In a first aspect, an embodiment of the present application provides a charging circuit, including: the charging circuit comprises a starting unit, an auxiliary power supply unit, a control unit and a power conversion unit, wherein the starting unit and the control unit are respectively connected with a first input end of the charging circuit through a Controller Area Network (CAN) bus, the starting unit is used for controlling the charging circuit to enter a charging state according to a first CAN signal input by the first input end of the charging circuit, the auxiliary power supply unit works in the charging state to supply power to the control unit and the power conversion unit, and the power conversion unit converts alternating current input voltage input by a second input end of the charging circuit into direct current output voltage under the control of the control unit and outputs the direct current output voltage through an output end of the charging circuit; the control unit is used for controlling the charging circuit to enter a standby state according to a second CAN signal input by the first input end of the charging circuit, and the auxiliary power supply unit stops working in the standby state.

According to the charging circuit, the working state of the charging circuit CAN be switched only according to the signals input by the CAN bus, and the auxiliary power supply unit does not work completely when the charging circuit is in the standby state, so that the control unit and the power conversion unit powered by the auxiliary power supply unit do not work, and the standby power consumption of the charging circuit is reduced; the first CAN signal and the second CAN signal are input into the charging circuit through the CAN bus, so that no separate signal line is needed to be added, the complexity of the design of the charging circuit CAN be simplified, and the influence of line-to-line interference is avoided; meanwhile, the cost-increasing electric appliance is not needed, and the hardware cost can be saved.

Further, the switching from the charging state to the standby state is triggered by the control unit in the embodiment of the application, so that the starting unit does not work in the charging state, power consumption is further reduced, interference is avoided, in addition, the control unit CAN process the CAN signal, and compared with signals in other formats, the control unit is low in modification cost.

According to the first aspect, in a first possible implementation manner of the charging circuit, a first input end of the startup unit is connected to a first input end of the charging circuit through a CAN bus, and an output end of the startup unit is connected to a first input end of the auxiliary power supply unit; the second input end of the auxiliary power supply unit is connected with the first output end of the control unit, the first output end of the auxiliary power supply unit is connected with the second input end of the control unit, the second output end of the auxiliary power supply unit is connected with the second input end of the power conversion unit, the first input end of the control unit is connected with the first input end of the charging circuit through a CAN bus, and the second output end of the control unit is connected with the third input end of the power conversion unit; the first input end of the power conversion unit is connected with the second input end of the charging circuit, and the output end of the power conversion unit is connected with the output end of the charging circuit.

According to a first possible implementation manner of the first aspect, in a second possible implementation manner of the charging circuit, the charging circuit further includes a switch, the switch is connected to the third output end of the control unit, the switch is connected to a path where the first input end of the charging circuit, the startup unit, and the auxiliary power supply unit are located, and when the switch is turned off, the path is turned off.

In this way, the power consumption of the auxiliary power supply unit is not affected when the path is disconnected, and the units on the path are not interfered by other CAN signals during the disconnection of the switch.

In a third possible implementation form of the charging circuit according to the second possible implementation form of the first aspect, the switch is connected between the first input terminal of the startup unit and the first input terminal of the charging circuit.

After the switch is switched off, the auxiliary power supply unit and the starting unit do not consume power, so that the power consumption of the charging circuit can be further reduced.

In a fourth possible implementation form of the charging circuit according to the second possible implementation form of the first aspect, the switch is connected between the output of the startup unit and the first input of the auxiliary power supply unit.

In this way, the flexibility of the setting of the switch can be improved.

In a fifth possible implementation form of the charging circuit according to the second possible implementation form of the first aspect, the switch is connected inside the starting unit.

In this way, the flexibility of the setting of the switch can be improved.

According to a sixth possible implementation manner of the charging circuit, in the second possible implementation manner of the first aspect, the first CAN signal and the second CAN signal are pulse width modulation signals, and the first CAN signal and the second CAN signal are the same or different.

When the charging circuit does not comprise a switch, the first CAN signal and the second CAN signal CAN be set to be different, when the charging circuit comprises a switch, the first CAN signal and the second CAN signal CAN be set to be the same (or different), so that the control unit CAN control the auxiliary power supply unit to be closed according to the received second CAN signal, and the startup unit CAN not influence the process.

In a seventh possible implementation manner of the charging circuit according to any one of the second to sixth possible implementation manners of the first aspect, the switch is a normally closed switch, and in the charging state, the control unit is further configured to output a control signal through a third output terminal to control the switch to remain open.

By the mode, the starting unit CAN respond to the first CAN signal at any time in the standby state, so that the charging circuit CAN conveniently enter the charging state; under the charging state, the switch is disconnected, the starting unit does not respond to the CAN signal any more, and the starting unit and the auxiliary power supply unit connected with the starting unit are not influenced by the CAN signal.

According to the first aspect and any one of the above first aspect, in an eighth possible implementation manner of the charging circuit, the starting unit includes a filter component and an isolation device, one end of the filter component is connected to the first input end of the starting unit, the other end of the filter component is connected to one end of the isolation device, the other end of the isolation device is connected to the output end of the starting unit, the filter component is configured to rectify and filter the first CAN signal to obtain a rectified and filtered signal, and the isolation device is configured to convert the rectified and filtered signal into a current signal for operating the auxiliary power supply unit.

Through the combination of the filter assembly and the isolation device, the first CAN signal is converted into the output signal of the starting unit (namely the starting signal of the auxiliary power supply unit), so that the working state of the charging circuit CAN be controlled through the first CAN signal, and the isolation device CAN be used for avoiding the interference caused by electric connection.

Waveform and filtering component, the isolation device parameter of first CAN signal CAN be through designing for the unit of starting machine CAN not respond to other signals outside the first CAN signal, thereby CAN realize making auxiliary power supply unit normal work through first CAN signal, and the unit of starting machine does not receive the interference of other signals of transmission on the CAN bus.

In a ninth possible implementation form of the charging circuit according to the eighth possible implementation form of the first aspect, the isolation device comprises an optocoupler isolator.

By the mode, the signals in other forms such as optical signals and the like can be transmitted in the starting unit, and interference caused by electric connection is avoided.

According to the first aspect and any one of the above possible implementation manners of the first aspect, in a tenth possible implementation manner of the charging circuit, the charging circuit further includes a rectifying and filtering unit, an input end of the rectifying and filtering unit is connected to the second input end of the charging circuit, a first output end of the rectifying and filtering unit is connected to the third input end of the auxiliary power supply unit, a second output end of the rectifying and filtering unit is connected to the second input end of the starting unit, and the rectifying and filtering unit converts an ac input voltage input from the input end into a power supply voltage of the auxiliary power supply unit and the starting unit.

In this way, the auxiliary power supply unit and the startup unit can be supplied with the supply voltage.

In a second aspect, embodiments of the present application provide a charging pile, which includes a charging control system and a charging circuit according to any one of the above first aspects, wherein an output end of the charging control system is connected to an input end of the charging circuit through a CAN bus.

Through this kind of mode, can reduce the stand-by power consumption who fills electric pile, and practice thrift the hardware cost who fills electric pile.

According to a second aspect, in a first possible implementation manner of the charging pile, the charging control system is configured to output a first CAN signal to control the charging circuit to enter a charging state when the charging pile needs to charge the device to be charged, and output a second CAN signal to control the charging circuit to enter a standby state when the charging pile needs to stop charging the device to be charged.

By the mode, when the charging circuit enters the charging state, the charging pile outputs voltage, the charging equipment can be charged, when the charging circuit enters the standby state, the charging pile does not output voltage, the charging for the charging equipment is stopped, and the switching of the working state of the charging pile can be realized by controlling the signal output by the charging control system.

These and other aspects of the present application will be more readily apparent from the following description of the embodiment(s).

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate exemplary embodiments, features, and aspects of the application and, together with the description, serve to explain the principles of the application.

Fig. 1 shows a control circuit 10 according to the prior art.

Fig. 2 shows a charge control circuit 20 according to the prior art.

Fig. 3 shows an exemplary application scenario of the charging circuit 30 according to the embodiment of the present application.

Fig. 4 shows an exemplary block diagram of the charging circuit 30 according to an embodiment of the present application.

Fig. 5 shows an exemplary structure diagram of the starting unit 301 according to an embodiment of the present application.

Fig. 6 illustrates an exemplary block diagram of a filtering component 3011 according to an embodiment of the present application.

Fig. 7 illustrates an exemplary block diagram of an isolation device 3012 according to an embodiment of the present application.

Fig. 8 illustrates an exemplary block diagram of the auxiliary power supply unit 302 according to an embodiment of the present application.

Fig. 9 shows an exemplary structure diagram of the driving module 3021 according to an embodiment of the present application.

Fig. 10 shows an exemplary block diagram of the charging circuit 30 according to an embodiment of the present application.

Fig. 11 shows an exemplary schematic diagram of a possible arrangement of the switch K1 according to an embodiment of the present application.

Fig. 12a and 12b show exemplary schematic diagrams of possible arrangements of the switch K1 according to an embodiment of the present application.

Fig. 13 shows an exemplary schematic diagram of a possible arrangement of the switch K1 according to an embodiment of the present application.

Fig. 14 illustrates an exemplary block diagram of a charging post 300 according to an embodiment of the present application.

Fig. 15 illustrates an exemplary workflow of a charging pole 300 according to an embodiment of the present application.

Detailed Description

Various exemplary embodiments, features and aspects of the present application will be described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers can indicate functionally identical or similar elements. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present application. It will be understood by those skilled in the art that the present application may be practiced without some of these specific details. In some instances, methods, means, elements and circuits that are well known to those skilled in the art have not been described in detail so as not to obscure the present application.

In order to reduce the standby power consumption of the charging pile, a control circuit 10 is proposed in the prior art, as shown in fig. 1. The control circuit 10 is applied to a charging pile, and may include a control system 11, an ac contactor 12, and a plurality of charging modules (13-15, three are taken as examples in the figure) connected in parallel, when the charging pile is in a standby state, the control system 11 controls the ac contactor 12 to be disconnected, and when the charging pile needs to work, the control system 11 controls the ac contactor 12 to be closed, so that the reduction of the standby power consumption of the charging pile is realized. However, since the ac input voltage Vin is large, the requirement on the power parameter of the ac contactor 12 is high, which may increase the hardware cost of the charging pile; moreover, the addition of the ac contactor 12 causes a certain power consumption when the ac contactor is closed, and although the standby state can reduce the power consumption, the effect of reducing the power consumption is not good in general; in addition, a certain time is consumed for the control system 11 to send out the control signal so that the ac contactor 12 is closed, and in addition, the time for the ac input voltage Vin to be input to the charging modules 13 to 15 through the closed ac contactor 12 so that the charging modules 13 to 15 work usually needs more than 10S to actually start charging, so that the charging efficiency of the charging pile is reduced.

The second prior art proposes another charge control circuit 20. As shown in fig. 2. Compared with the scheme of the first prior art, the alternating-current contactor is removed, the low-voltage power supply 22 and the contactor 23 (such as a relay switch) are additionally arranged, and the contactor 23 is connected with the low-voltage power supply 22, the charging modules (24-26, three are taken as an example in the figure) and the control system 21. When filling electric pile and being in standby state, control system 21 control contactor 23 disconnection, fill electric pile and need the during operation, control system 21 control contactor 23 closure to realize the reduction of stand-by power consumption. Compared with the first scheme in the prior art, although the high-cost alternating current contactor is not needed, the number of the wires connecting the charging modules 24 to 26 is more, interference exists among the wires, signal transmission is not facilitated, and circuit cost is increased; the connection of the charging modules 24-26 with the low voltage power supply 22 requires a new interface, so that the structure of the charging module is changed, the charging module cannot be compatible with the existing standard charging module, the complexity of the charging control circuit is increased, and the cost of the control circuit is not facilitated.

Therefore, neither the first prior art nor the second prior art can achieve reduction of the standby power consumption of the charging pile with low hardware cost.

In order to solve the technical problem, the application provides a charging circuit, the charging circuit of the embodiment of the application can simultaneously reduce the hardware cost and the standby power consumption of the charging circuit, and the method can be applied to a charging pile, so that the hardware cost and the standby power consumption of the charging pile are reduced.

As shown in fig. 3, the charging circuit 30 according to the embodiment of the present disclosure may be disposed in the charging pile 300, and the charging pile 300 may be connected to the interface 41 of the electric vehicle 400 through the interface 32. The charging post 300 may further include a charging control system 31 connected to the charging circuit 30 of the charging post 300 through a CAN bus. In the prior art, a Controller Area Network (CAN) bus may be used to transmit charging parameters, such as the magnitude of output voltage, during the process of charging an electric vehicle by a charging pile. On this basis, the CAN bus of the embodiment of the present application may also be used to transmit a first CAN signal and a second CAN signal between the charging control system 31 and the charging circuit 30, where the first CAN signal and the second CAN signal may be used to control the charging circuit 30 to enter the charging state and the standby state, respectively.

In a possible implementation manner, in a case that the charging pile 300 is not connected to the electric vehicle 400, the charging circuit 30 is in a standby state, so that power consumption of the charging pile 300 is saved. In this case, the charging control system 31 does not need to send a signal to the charging circuit 30, and no signal is transmitted on the CAN bus.

In the case that the charging pile 300 is connected to the electric vehicle 400, the charging pile 300 may receive parameter information of the electric vehicle 400 through the interface 32. The parameter information sent by the electric vehicle 400 may include parameters related to charging, such as the magnitude range of voltage and current that the electric vehicle 400 can withstand, the percentage of the present electric quantity, and the like. The charging control system 31 may analyze and determine whether the electric vehicle 400 needs to be charged and the voltage level that the interface 32 should output according to the received parameter information.

In a possible implementation manner, the charging control system 31 may determine that the electric vehicle 400 needs to be charged according to the received parameter information, in which case, the charging control system 31 may output the first CAN signal to control the charging circuit 30 to enter a charging state, so that the charging circuit 30 operates normally to charge the electric vehicle 400.

In a possible implementation manner, the charging control system 31 may determine that charging to the electric vehicle 400 is not required (for example, the electric vehicle is fully charged) according to the received parameter information, in which case, the charging control system 31 may output the second CAN signal to control the charging circuit 30 to enter the standby state, so as to save power.

Fig. 4 shows an exemplary block diagram of the charging circuit 30 according to an embodiment of the present application. As shown in fig. 4, the charging circuit 30 according to the embodiment of the present application may include: the charging circuit comprises a starting unit 301, an auxiliary power supply unit 302, a control unit 303 and a power conversion unit 305, wherein the starting unit 301 and the control unit 303 are respectively connected with a first input end (end a) of the charging circuit 30 through a controller area network CAN bus, the starting unit 301 is used for controlling the charging circuit 30 to enter a charging state according to a first CAN signal input by the first input end (end a) of the charging circuit 30, in the charging state, the auxiliary power supply unit 302 works to supply power to the control unit 303 and the power conversion unit 305, and the power conversion unit 305 converts an alternating current input voltage Vin input by a second input end (end B) of the charging circuit 30 into a direct current output voltage Vout and outputs the direct current output voltage Vout through an output end (end C) of the charging circuit 30 under the control of the control unit 303; the control unit 303 is configured to control the charging circuit 30 to enter a standby state according to a second CAN signal input by a first input terminal (terminal a) of the charging circuit 30, where the auxiliary power supply unit 302 stops working in the standby state.

According to the charging circuit, the starting unit receives the first CAN signal to enable the auxiliary power supply unit to enter the working state, the auxiliary power supply unit supplies power to the control unit to enable the control unit to normally work, and therefore the charging circuit enters the charging state; and the control unit under normal work receives a second CAN signal to enable the auxiliary power supply unit to enter a work stop state, so that the charging circuit enters a standby state. The charging circuit of the embodiment of the application CAN realize the switching of the working state of the charging circuit only according to the signals input by the CAN bus, and the auxiliary power supply unit does not work completely when the charging circuit is in the standby state, so that the control unit and the power conversion unit powered by the auxiliary power supply unit do not work, and the standby power consumption of the charging circuit is reduced; the first CAN signal and the second CAN signal are input into the charging circuit through the CAN bus, so that no separate signal line is needed to be added, the complexity of the design of the charging circuit CAN be simplified, and the influence of line-to-line interference is avoided; meanwhile, the cost-increasing electric appliance is not needed, and the hardware cost can be saved.

In one possible implementation manner, as shown in fig. 4, a first input terminal (terminal a) of the startup unit 301 is connected to a first input terminal (terminal a) of the charging circuit 30 through a CAN bus, and an output terminal (terminal b) of the startup unit 301 is connected to a first input terminal (terminal c) of the auxiliary power supply unit 302;

a second input end (h end) of the auxiliary power supply unit 302 is connected to a first output end (g end) of the control unit 303, a first output end (d end) of the auxiliary power supply unit 302 is connected to a second input end (e end) of the control unit 303, and a second output end (k end) of the auxiliary power supply unit 302 is connected to a second input end (u end) of the power conversion unit 305;

a first input end (f end) of the control unit 303 is connected to a first input end (a end) of the charging circuit 30 through a CAN bus, and a second output end (i end) of the control unit 303 is connected to a third input end (j end) of the power conversion unit 305;

a first input terminal (terminal n) of the power conversion unit 305 is connected to a second input terminal (terminal B) of the charging circuit 30, and an output terminal (terminal q) of the power conversion unit 305 is connected to an output terminal (terminal C) of the charging circuit 30.

The startup unit 301 CAN receive a first CAN signal input by a CAN bus through a first input end, generate a current signal I according to the received first CAN signal, and output the current I to the auxiliary power supply unit 302 through an output end to control the auxiliary power supply unit 302 to start working; the auxiliary power supply unit 302 can enter a working state through a current signal I received by a first input end (end c), and supplies power to the control unit 303 through a first output end (end d), so that the control unit 303 starts to work; the auxiliary power supply unit 302 may also supply power to the power conversion unit 305 through a second output terminal (terminal k), and the control unit 303 may output a control signal S3 to the power conversion unit 305 through the second output terminal (terminal i) to enable the power conversion unit 305 to start operating; the power conversion unit 305 may receive an ac input voltage Vin through a first input terminal (n terminal), convert the ac input voltage Vin into a dc output voltage Vout, and output the dc output voltage Vout to an external circuit through an output terminal. In this case, the charging circuit 30 may enter a charging state, and the output terminal of the power conversion unit 305 may output the converted dc output voltage Vout continuously.

In the charging state, the control unit 303 may be configured to receive a charging related parameter transmitted by the CAN bus, such as a magnitude of an output voltage, and adjust the output voltage of the power conversion unit 305 according to the received parameter to meet a parameter requirement.

The control unit 303 of the embodiment of the present application may receive a second CAN signal input by the CAN bus through the first input terminal (terminal f), generate a control signal S1 according to the received second CAN signal, and output the control signal S1 to the auxiliary power supply unit 302 through the first output terminal (terminal g), so as to control the auxiliary power supply unit 302 to stop working. After the auxiliary power supply unit 302 stops working, no signal is output from the first output terminal (terminal d) and the second output terminal (terminal k), and power cannot be supplied to the control unit 303 and the power conversion unit 305, so the control unit 303 and the power conversion unit 305 also stop working, the power conversion unit 305 does not convert the ac input voltage Vin, and does not output the dc output voltage Vout, the charging state is ended, and the charging circuit 30 enters the standby state.

In this way, the startup unit 301 and the control unit 303 can respectively control the charging circuit 30 to enter the charging state and the standby state.

Fig. 5 shows an exemplary structure diagram of the starting unit 301 according to an embodiment of the present application. As shown in fig. 5, the starting unit 301 may include a filter component 3011 and an isolation device 3012, where one end of the filter component 3011 is connected to a first input end (a end) of the starting unit 301, the other end of the filter component 3011 is connected to one end of the isolation device 3012, the other end of the isolation device 3012 is connected to an output end (b end) of the starting unit 301, the filter component 3011 is configured to rectify and filter the first CAN signal to obtain a rectified and filtered signal, and the isolation device 3012 is configured to convert the rectified and filtered signal into a current signal I for operating the auxiliary power supply unit 302.

Through the combination of filtering subassembly and isolation device, realized converting first CAN signal into the output signal (current signal I, auxiliary power supply unit's start signal promptly) of the unit of starting drive for CAN realize the control to charging circuit operating condition through first CAN signal, and isolation device's use CAN avoid the electric interference that brings.

For example, the first CAN signal and the second CAN signal may both be signals that conform to the CAN protocol that may be transmitted over the CAN bus. One end of the filtering component 3011 may receive the first CAN signal. In one possible implementation, the first CAN signal may be, for example, a differential Pulse Width Modulation (PWM) signal, and the filtering component 3011 may perform rectification filtering on the received first CAN signal, and output the filtered signal to the isolation device 3012. The isolation device 3012 may generate a current signal I according to the received filtered signal and output the current signal I through the other end of the isolation device 3012, that is, the output end (b end) of the starting unit 301. When the duty ratios of the first CAN signals are different, the isolation device 3012 may generate currents of different magnitudes, and the duty ratio of the first CAN signal may be preset, so that the duty ratios of the first CAN signal and other PWM signals are different, only when the received signal is the first CAN signal, the current signal I output by the isolation device 3012 may control the auxiliary power supply unit 302 to start working, and if the received signal is the other signal, the output current signal may not enable the auxiliary power supply unit 302 to start working.

For example, the longest duration of the positive pulse of the other CAN signal that CAN be input to the startup unit 301 via the CAN bus during the use of the charging pile (e.g., 5 msec) may be counted, and the first CAN signal may be set such that the positive pulse of the first CAN signal may last longer than the other CAN signal (e.g., 20 msec). On this basis, parameters of devices such as a capacitor and a resistor in the filter component 3011 may be determined, so that only after the first CAN signal is input to the filter component 3011, the output rectified and filtered signal CAN drive the light emitter of the isolation device 3012 to emit light with a sufficiently high intensity, so that the light receiver of the isolation device 3012 CAN flow a sufficiently high current signal I to drive the auxiliary power supply unit 302 to start operating; after other CAN signals are input to the filter module 3011 with the same parameters, the light emitter cannot emit light with sufficient intensity, so that the light receiver cannot output the current signal I capable of driving the auxiliary power supply unit, and the auxiliary power supply unit 302 cannot start to operate.

In this way, the startup unit 301 does not respond to other signals except the first CAN signal, so that the auxiliary power supply unit 302 CAN work normally through the first CAN signal, and the startup unit 301 is not interfered by other signals transmitted on the CAN bus.

In one possible implementation, the signals transmitted through the CAN bus may come from the charging control system 31, or from other signal sources. The startup element 301 may also be configured to receive a signal S0 from another signal source through the first input (terminal a) and to respond to the signal S0. For example, when the charging circuit 30 is applied to a charging pile, the charging pile may further be provided with another signal source, such as a manually controllable button switch, which is connected to the CAN bus and capable of sending a signal, and if the user presses the manual switch, the manual switch may send a signal S0 to the first input end (end a) of the charging circuit 30. The signal S0 can control the startup element 301 to output the current signal I so that the auxiliary power supply unit 302 operates normally. The present disclosure does not limit the specific arrangement of the input signal of the first input terminal of the charging circuit 30.

Fig. 6 illustrates an exemplary block diagram of a filtering component 3011 according to an embodiment of the present application. As shown in fig. 6, the first CAN signal may be a differential input signal, the filtering component 3011 may include a diode D1, a resistor R1, a resistor R2, a resistor R3, and a capacitor C1, one end of the diode D1 is connected to one end of the differential input terminal, the other end of the diode D1 is connected to one end of the resistor R1, the other end of the resistor R1 is connected to one end of the capacitor C1 and one end of the resistor R2, the other end of the capacitor C1 is connected to the other end of the differential input terminal, the other end of the resistor R2 is connected to one end of the resistor R3 and one end of the differential output terminal, and the other end of the resistor R3 is connected to the other end of the capacitor C1 and the other end of the differential output terminal, so as to implement rectification filtering on the input differential first CAN signal, and obtain a differential filtered signal S4. In a possible implementation manner, positions of the diode D1, the resistors R1, R2, R3, and the capacitor C1 in the filtering component 3011 according to this embodiment may also be changed, and the filtering component 3011 may also be configured in other arrangement manners including capacitors, resistors, or other types of devices, which is not limited in this application as long as the corresponding functions can be performed.

Fig. 7 illustrates an exemplary block diagram of an isolation device 3012 according to an embodiment of the present application. As shown in fig. 7, the isolation device 3021 comprises an optocoupler isolator.

For example, the isolation device 3012 may transmit electrical signals through light, and may include a light emitter D0 (e.g., an infrared light emitting diode LED) and a light receiver T1 (e.g., a light sensitive semiconductor triode). When the isolation device 3012 inputs the signal S4 rectified and filtered by the filtering component 3011, the light emitter D0 may emit light, and the light receiver T1 may be turned on after receiving the light, so that a current signal I flows through the light receiver and is output by the light receiver.

In a possible implementation manner, the isolation device 3012 in this embodiment may also use a capacitive isolation device or a magnetic isolation device, and this application is not limited thereto as long as the corresponding function can be completed.

In this way, the startup unit 301 CAN output current according to the received first CAN signal, so that the auxiliary power supply unit 302 CAN normally operate when receiving current. Furthermore, the isolating device can be used for transmitting signals inside the starting unit through signals in other forms such as optical signals, and interference caused by electric connection is avoided.

Fig. 8 illustrates an exemplary block diagram of the auxiliary power supply unit 302 according to an embodiment of the present application. As shown in fig. 8, the auxiliary power supply unit 302 may include a driving module 3021 and an auxiliary power supply module 3022, wherein a first input terminal (v terminal) of the driving module 3021 may be connected to a first input terminal (c terminal) of the auxiliary power supply unit 302, a second input terminal (z terminal) of the driving module 3021 may be connected to a second input terminal (h terminal) of the auxiliary power supply unit 302, an output terminal (w terminal) of the driving module 3021 may be connected to an input terminal VCC of the auxiliary power supply module 3022, and a first output terminal (x terminal) and a second output terminal (y terminal) of the auxiliary power supply module 3022 may be connected to a first output terminal (d terminal) and a second output terminal (k terminal) of the auxiliary power supply unit 302, respectively.

In one possible implementation, the driving module 3021 is configured to output a voltage to the VCC terminal of the auxiliary power module 3022 according to the current signal I, and the VCC terminal of the auxiliary power module 3022 may supply power to the control unit 303 and the power conversion unit 305 when a voltage is input, so that the auxiliary power unit 302 operates normally; the driving module 3021 is further configured to stop the voltage output to the auxiliary power module 3022 according to a control signal S1 (see fig. 11) from the first output terminal (terminal g) of the control unit 303, the VCC terminal of the auxiliary power module 3022 has no voltage input, and the control unit 303 and the power conversion unit 305 cannot be supplied with power, so that the auxiliary power unit 302 stops operating.

Fig. 9 shows an exemplary structure diagram of the driving module 3021 according to an embodiment of the present application. As shown in fig. 9, in one possible implementation, the driving module 3021 includes an N-type metal oxide semiconductor transistor Q1 (abbreviated as NMOS transistor Q1), and the driving module 3021 may further connect a differential input voltage (e.g., rectified and filtered ac voltages BUS + and BUS-), wherein the positive input voltage BUS + and the negative input voltage BUS-may be respectively connected to two ends of the light receiver of the isolation device 3012 through a resistor, a diode, a switch, and other devices, so that when the light receiver is turned on, a path is formed between the positive input voltage BUS +, the light receiver, and the negative input voltage BUS-, and a current signal I is output from one end of the light receiver connected to the negative input voltage BUS-.

In one possible implementation, the end of the light receptor that is connected to the negative input voltage BUS-may also be connected to the gate of Q1, and thus, the current signal I also flows to the gate of Q1. The drain of Q1 is connected to the positive input voltage BUS + through relay R5. The source of Q1 is connected to the output (w terminal) of driver module 3021 through resistor R7.

In a possible implementation manner, the intensity of the light emitted by the light emitter determines the magnitude of the current allowed to flow in the light receiver, and the parameter of the first CAN signal is preset, so that when the first CAN signal is input to the starting unit 301, the current signal I obtained according to the intensity of the light emitted by the light emitter satisfies the requirement that the NMOS transistor Q1 is turned on. In this case, the VCC terminal (i.e., the input terminal of the auxiliary power module 3022, i.e., the output terminal (w terminal) of the driving module 3021) is pulled up by the source voltage of Q1, so that the auxiliary power module 3022 is driven, the auxiliary power unit 302 starts to operate and supplies power (see fig. 8) to the control unit 303 and the power conversion unit 305 in fig. 4 through the first output terminal (x terminal) and the second output terminal (y terminal) of the auxiliary power module 3022, for example, so that the control unit 303 starts to operate; when the digital conversion unit 303 outputs a control signal to the power conversion unit 305, the power conversion unit 305 also starts operating.

In a possible implementation manner, a bias resistor R6 is further connected between the source and the gate of the Q1, and after the source potential of the Q1 is pulled high, the bias resistor R6 may provide a bias voltage for the NMOS transistor to maintain the conducting state of the NMOS transistor, so that the auxiliary power supply unit 302 may operate continuously.

In one possible implementation, the auxiliary power supply unit 302 may be deactivated by controlling the relay R5 to open. For example, the relay R5 may be further connected to the second input terminal (terminal h) of the auxiliary power supply unit 302 to receive the control signal S1 (see fig. 10) output by the control unit 303. The relay R5 may be configured to remain closed when no control signal S1 is received. Under the control of the control signal S1, the relay R5 may be opened. When R5 is turned off, no current flows between the drain and the source of the NMOS transistor, the voltage at the VCC terminal connected to the source of Q1 (i.e., the input terminal of the auxiliary power module 3022) decreases, and the auxiliary power module 3022 cannot drive, so that the auxiliary power unit 302 stops operating. Since the auxiliary power supply unit 302 does not supply power to the control unit 303 and the power conversion unit 305 any more when the auxiliary power supply unit 302 stops operating, the control unit 303 and the power conversion unit 305 also stop operating.

In one possible implementation, after the control unit 303 stops operating, the relay R5 may resume the closed state, so that the auxiliary power supply unit 302 can operate again upon receiving the current signal I.

It should be understood by those skilled in the art that the above-described structure of the auxiliary power supply unit 302 is only one possible arrangement, and the possible arrangement of the auxiliary power supply unit 302 may be configured to be driven by a control signal, for example, the driving module 3021 may be enabled to generate a control signal according to the current signal I, the control signal drives the auxiliary power supply module 3022 to enable the auxiliary power supply unit 302 to operate, and so on, as long as the corresponding functions can be implemented, and therefore, the detailed description thereof is omitted.

In this way, the start and stop of the operation of the auxiliary power supply unit 302 can be achieved.

Fig. 10 shows an exemplary block diagram of the charging circuit 30 according to an embodiment of the present application. As shown in fig. 10, the charging circuit 30 of the embodiment of the present application further includes a rectifying and filtering unit 304, an input end (end m) of the rectifying and filtering unit 304 is connected to a second input end (end B) of the charging circuit 30, a first output end (end o) of the rectifying and filtering unit 304 is connected to a third input end (end p) of the auxiliary power unit 302, a second output end (end r) of the rectifying and filtering unit 304 is connected to a second input end (end s) of the starting unit 301, and the rectifying and filtering unit 304 converts an ac input voltage Vin input by an input end into a power voltage of the auxiliary power unit 302 and the starting unit 301. In this way, the auxiliary power supply unit and the startup unit can be supplied with the supply voltage.

The rectifying and filtering unit 304 may be configured to rectify and filter the ac input voltage Vin to provide a power supply voltage for the auxiliary power supply unit 302 and the starting unit 301, so that the power conversion unit 305 can complete obtaining and outputting the dc output voltage Vout under the control of the output signal S3 of the control unit 303 when the auxiliary power supply unit 302 provides the power supply voltage.

In a possible implementation manner, after the auxiliary power supply unit 302 operates, other signals may be transmitted on the CAN bus, for example, the control unit 303 may need to receive signals through the CAN bus and control the power conversion unit 305 to adjust the magnitude of the output dc output voltage Vout according to the received signals. In this case, in order to further prevent the startup unit 301 from responding to other signals transmitted on the CAN bus and prevent the generated current signal from causing unnecessary power consumption of diodes, resistors, and the like of the auxiliary power supply unit 302, the embodiments of the present application propose possible implementations as shown in fig. 11 to fig. 13.

In a possible implementation manner, the charging circuit 30 further includes a switch K1, the switch K1 is connected to the third output terminal (terminal t) of the control unit 303, and the switch K1 is connected in a path where the first input terminal (terminal a) of the charging circuit 30, the startup unit 301, and the auxiliary power supply unit 302 are located, and when the switch K1 is turned off, the path is turned off. In this way, the power consumption of the auxiliary power supply unit is not affected during the disconnection of the path, and the units on the path are not interfered by other CAN signals during the disconnection of the switch.

As CAN be seen from the above description, in the embodiment of the present application, the signal received from the start-up unit 301 to the CAN bus input to the current signal I input to the auxiliary power supply unit 302 needs to go through three stages: in the first stage, a signal is input to the filtering component 3011; in the second stage, the filtered signal S4 is input to the isolation device 3012; in the third stage, the current signal generated by the isolation device 3012 is input to the auxiliary power supply unit 302. Therefore, the switch K1 can be provided between the paths corresponding to any one of the above-described stages. By turning off the K1, no current signal can be input to the auxiliary power supply unit 302 without affecting the power consumption of the auxiliary power supply unit 302 and without interfering with the operation of the control unit 303.

Fig. 11 shows an exemplary schematic diagram of a possible arrangement of the switch K1 according to an embodiment of the present application. The switch K1 is connected between the first input terminal (terminal a) of the starting unit 301 and the first input terminal (terminal a) of the charging circuit 30. After the switch is switched off, the auxiliary power supply unit and the starting unit do not consume power, so that the power consumption of the charging circuit can be further reduced.

For example, the switch K1 may be disposed between the paths corresponding to the first stage. In this case, when the K1 is turned off, the signal transmitted on the CAN bus does not enter the filter component 3011, and therefore does not necessarily reach the subsequent second and third stages, so that the start-up unit 301 has no current signal input to the auxiliary power supply unit 302. In this case, the driving module 3021 of the auxiliary power supply unit 302 does not consume power, and devices such as a resistor and a capacitor in the startup unit 301 do not consume power, so that the power consumption of the charging circuit 30 can be further reduced.

In a possible implementation manner, the switch K1 is a normally closed switch, and in the charging state, the control unit 303 is further configured to output a control signal S2 through a third output terminal (terminal t) to control the switch K1 to keep open.

For example, in the absence of signal control, normally closed switch K1 may remain closed. In this way, after the charging circuit 30 enters the standby state, since the control unit 303 stops operating, the switch K1 is not controlled by a signal, and returns to the closed state, and when a new first CAN signal is input to the CAN bus, the startup unit 301 CAN operate normally.

By the mode, the starting unit CAN respond to the first CAN signal at any time in the standby state, and the charging circuit CAN conveniently enter the charging state. Under the charging state, the switch is disconnected, the starting unit does not respond to the CAN signal any more, and the starting unit and the auxiliary power supply unit connected with the starting unit are not influenced by the CAN signal.

Fig. 12a and 12b show exemplary schematic diagrams of possible arrangements of the switch K1 according to an embodiment of the present application. In one possible implementation, the switch K1 is connected inside the starting unit 301.

For example, the switch K1 may be disposed between the paths corresponding to the second stage. In this case, when K1 is turned off, the filtered signal output by the filtering component 3011 does not enter the isolation device 3012, and therefore does not necessarily reach the subsequent third stage, so that no current signal is input to the auxiliary power supply unit 302. In this case, the driving module 3021 of the auxiliary power supply unit 302 does not consume power, and the devices such as a partial resistor and a capacitor in the startup unit 301 do not consume power, so that the power consumption of the charging circuit 30 can be reduced.

In one possible implementation, the switch K1 may also be disposed in the filtering component 3011. Those skilled in the art will appreciate that the switch K1 can be configured in a manner different from that described above, and the present application is not limited thereto as long as the corresponding function can be achieved.

In this way, the flexibility of the setting of the switch can be improved.

Fig. 13 shows an exemplary schematic diagram of a possible arrangement of the switch K1 according to an embodiment of the present application. Wherein the switch K1 is connected between the output terminal (terminal b) of the startup unit 301 and the first input terminal (terminal c) of the auxiliary power supply unit 302.

For example, the switch K1 may be disposed between the paths corresponding to the third stage. In this case, when K1 is turned off, the current signal generated by the isolation device 3012 does not enter the driving module 3021. In this case, the driving module 3021 of the auxiliary power supply unit 302 does not consume power, and power consumption of the charging circuit 30 can be reduced.

In this way, the flexibility of the setting of the switch can be improved.

In one possible implementation, the first and second CAN signals are pulse width modulated signals, and the first and second CAN signals are the same or different. For example, when the charging circuit does not include a switch, the first CAN signal and the second CAN signal may be set to be different, and when the charging circuit includes a switch, the first CAN signal and the second CAN signal may be set to be the same (or different), so that the control unit may control the auxiliary power supply unit to be closed according to the received second CAN signal, and the startup unit may not affect the process.

For example, when the charging circuit 30 does not include the switch K1, the first CAN signal and the second CAN signal may be set to be different, so that when the second CAN signal is input to the startup unit 301, the current signal output by the startup unit 301 cannot turn on the NMOS transistor Q1 of the driving module 3021. In this case, the control unit 303 may control the auxiliary power supply unit 302 to be closed according to the received second CAN signal without the startup unit 301 affecting this process.

In a possible implementation manner, when the charging circuit 30 includes the switch K1, the first CAN signal and the second CAN signal may be set to be the same, or the first CAN signal and the second CAN signal may also be set to be different, because in the charging state, the control unit 303 may control the switch K1 to be turned off, so that the operation state of the auxiliary power supply unit 302 is not affected by the startup unit 301 no matter what signal is received. In this case, the control unit 303 may control the auxiliary power supply unit 302 to be closed according to the received second CAN signal without the startup unit 301 affecting this process.

The embodiment of the present application further provides a charging pile 300, the charging pile 300 includes a charging control system 31 and a charging circuit 30 according to the embodiment of the present application, an output end of the charging control system 31 is connected to an input end of the charging circuit 30 through a CAN bus. Through this kind of mode, can reduce the stand-by power consumption who fills electric pile, and practice thrift the hardware cost who fills electric pile.

In a possible implementation manner, the charging control system 31 is configured to, when the charging pile 300 needs to charge the device to be charged, output a first CAN signal to control the charging circuit 30 to enter a charging state, and when the charging pile 300 needs to stop charging the device to be charged, output a second CAN signal to control the charging circuit 30 to enter a standby state. By the mode, when the charging circuit enters the charging state, the charging pile outputs voltage, the charging equipment can be charged, when the charging circuit enters the standby state, the charging pile does not output voltage, the charging for the charging equipment is stopped, and the switching of the working state of the charging pile can be realized by controlling the signal output by the charging control system.

In a possible implementation manner, the charging pile 300 may further be provided with an interface capable of being physically connected with the electric vehicle (for example, a CAN bus). When the electric vehicle is connected to the charging pile 300, the charging control system 31 may exchange data with a battery management system of the electric vehicle through the CAN bus, and receive charging parameter information, a command to start charging, a command to stop charging, and the like transmitted by the battery management system of the electric vehicle. Upon receiving a command to start charging, the charging control system may send a first CAN signal to the charging circuit 30. Upon receiving the command to stop charging, the charging control system 31 may send a second CAN signal to the charging circuit 30.

In a possible implementation manner, a button for manual control may also be provided on the charging pile 300, or a display device including a control may also be provided, the button and the display device may be connected to the charging control system 31, and when the electric vehicle and the charging pile are in a connected state, if the button is pressed by a user, or the control is triggered by the user, the charging control system 31 may receive an instruction from the charging pile that charging needs to be started and an instruction that charging needs to be stopped.

In a possible implementation manner, the charging pile 300 may further include a plurality of charging circuits 61-6n, as shown in fig. 14, where n is an integer greater than 1, the plurality of charging circuits 61-6n may be connected in parallel, and a structure of each charging circuit may be the same as a possible structure of the charging circuit 30. The output terminal of the charging control system 31 CAN be connected to the first input terminal (terminal a 1-terminal An) of each charging circuit through the CAN bus. When the power of the power battery of the electric vehicle is insufficient, the charging control system 31 may control all or part of the charging circuits 61-6n to enter a charging state to charge the electric vehicle connected to the charging pile.

Fig. 15 illustrates an exemplary workflow of the charging pile 300 according to an embodiment of the application. The following description will be given taking a charging circuit 62, which is one of a plurality of charging circuits, as an example.

In one possible implementation, when the charging circuit 62 is in a standby state and the charging control system 31 receives an instruction that charging needs to be started, the charging control system 31 may output a first CAN signal to the charging circuit 62. The startup unit of the charging circuit 62 CAN control the auxiliary power supply unit of the charging circuit 62 to work normally according to the received first CAN signal.

The command that the charging needs to be started can be sent by an electric automobile battery management system connected with the charging pile, and can also be triggered by a button on the charging pile or a display device after a user manually presses the button on the charging pile or triggers a control on the display device.

In one possible implementation, the first CAN signal is also input to the control unit of the charging circuit 62, but since the charging circuit 62 is in the standby state, the control unit of the charging circuit 62 is also in the shutdown state, and the control unit does not respond to the first CAN signal.

After the auxiliary power supply unit of the charging circuit 62 normally works, the task of the start-up unit of the charging circuit 62 is completed, under the condition that the first input end of the start-up unit is connected with the normally closed switch, the control unit of the charging circuit 62 can control the switch to be kept off by outputting a control signal, so that other signals (such as signals including charging related parameter information) cannot be input into the filter assembly of the start-up unit, the filter assembly does not have signal output, the current which may influence the working state of the auxiliary power supply unit connected with the isolation device cannot be generated in the isolation device, and further the working state of the control unit powered by the auxiliary power supply unit is prevented from being influenced. Thus, when the charging control system needs to exchange signals with other devices (such as a control unit) of the charging circuit through the CAN bus, the charging control system is not influenced by the starting unit.

After the auxiliary power supply unit of the charging circuit 62 works normally, the auxiliary power supply unit supplies power to the control unit and the power conversion unit of the charging circuit 62, so that the charging circuit 62 enters a charging state. The control unit can control the power conversion unit to convert alternating current into direct current. The converted dc power is output at the output of the charging circuit 62 and is used to charge an electrical device that needs to be charged, such as a power battery of an electric vehicle.

In one possible implementation, the charging control system 600 may output the second CAN signal when the charging circuit 62 is in the charging state and the charging control system 600 receives an instruction that charging needs to be stopped. The control unit may output a control signal to control the auxiliary power supply unit of the charging circuit 62 to stop operating according to the received second CAN signal. The control signal can be used, for example, to control a relay in the auxiliary power supply unit to be switched off, which relay can be connected to the supply voltage terminal of the auxiliary power supply unit and to the path of the output terminal.

In one possible implementation, the second CAN signal is also input to the start-up unit of the charging circuit 62, but since the connection of the start-up unit to the charging control system 600 has been disconnected by the switch, the start-up unit of the charging circuit 62 is in a deactivated state and does not respond to the second CAN signal.

After the auxiliary power supply unit of the charging circuit 62 stops operating, power is no longer supplied to the control unit and the power conversion unit of the charging circuit 62. The control unit and the power conversion unit stop working, and the normally closed switch of the starting unit is not controlled by the control unit any more after the control unit stops working, and returns to a closed state. The charging circuit 62 enters a standby state.

In the standby state, no other signals than the first CAN signal are transmitted between the charging control system 31 and the charging circuit 30, and no signal, for example, including information on a charging-related parameter, is input to the charging circuit on the CAN bus until the charging circuit 30 enters the charging state under the control of the first CAN signal.

The remaining charging circuits of the charging post 300 may perform the same function as the charging circuit 62.

It should be understood by those skilled in the art that the work flow of the charging control circuit 60 shown in fig. 15 is only an example, and the work flow may be adjusted as needed, for example, when the switch K1 is not included in any charging circuit, the control unit of the charging circuit does not send out a control signal for the switch K1, and the like, and the embodiment of the present application is not limited thereto.

The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of apparatus, systems, methods and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.

It is also noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by hardware (e.g., a Circuit or an ASIC) for performing the corresponding function or action, or by combinations of hardware and software, such as firmware.

While the invention has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Having described embodiments of the present application, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen in order to best explain the principles of the embodiments, the practical application, or improvements made to the technology in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A charging circuit, comprising: the charging circuit comprises a starting unit, an auxiliary power supply unit, a control unit and a power conversion unit, wherein the starting unit and the control unit are respectively connected with a first input end of the charging circuit through a Controller Area Network (CAN) bus,

the starting unit is used for controlling the charging circuit to enter a charging state according to a first CAN signal input by a first input end of the charging circuit, the auxiliary power supply unit works in the charging state to supply power to the control unit and the power conversion unit, and the power conversion unit converts alternating current input voltage input by a second input end of the charging circuit into direct current output voltage under the control of the control unit and outputs the direct current output voltage through an output end of the charging circuit;

the control unit is used for controlling the charging circuit to enter a standby state according to a second CAN signal input by the first input end of the charging circuit, and the auxiliary power supply unit stops working in the standby state.

2. The charging circuit of claim 1,

the first input end of the starting unit is connected with the first input end of the charging circuit through a CAN bus, and the output end of the starting unit is connected with the first input end of the auxiliary power supply unit;

the second input end of the auxiliary power supply unit is connected with the first output end of the control unit, the first output end of the auxiliary power supply unit is connected with the second input end of the control unit, and the second output end of the auxiliary power supply unit is connected with the second input end of the power conversion unit;

a first input end of the control unit is connected with a first input end of the charging circuit through a CAN bus, and a second output end of the control unit is connected with a third input end of the power conversion unit;

the first input end of the power conversion unit is connected with the second input end of the charging circuit, and the output end of the power conversion unit is connected with the output end of the charging circuit.

3. The charging circuit of claim 2, further comprising a switch, wherein the switch is connected to the third output terminal of the control unit, and the switch is connected to a path where the first input terminal of the charging circuit, the startup unit, and the auxiliary power supply unit are located, and when the switch is turned off, the path is turned off.

4. The charging circuit of claim 3, wherein the switch is connected between the first input of the startup element and the first input of the charging circuit.

5. The charging circuit of claim 3, wherein the switch is connected between the output of the startup unit and the first input of the auxiliary power supply unit.

6. The charging circuit of claim 3, wherein the switch is connected inside the starting unit.

7. The charging circuit of any of claims 3-6, wherein the first and second CAN signals are pulse width modulated signals, the first and second CAN signals being the same or different.

8. The charging circuit according to any of claims 3-7, wherein the switch is a normally closed switch, and in the charging state, the control unit is further configured to output a control signal via a third output terminal to control the switch to remain open.

9. The charging circuit according to any one of claims 1 to 8, wherein the starting unit comprises a filter component and an isolation device, one end of the filter component is connected to the first input end of the starting unit, the other end of the filter component is connected to one end of the isolation device, the other end of the isolation device is connected to the output end of the starting unit,

the filter assembly is used for rectifying and filtering the first CAN signal to obtain a rectified and filtered signal, and the isolation device is used for converting the rectified and filtered signal into a current signal which enables the auxiliary power supply unit to work.

10. The charging circuit of claim 9, wherein the isolation device comprises an optocoupler isolator.

11. The charging circuit according to any one of claims 1 to 10, further comprising a rectifying and filtering unit, wherein an input terminal of the rectifying and filtering unit is connected to a second input terminal of the charging circuit, a first output terminal of the rectifying and filtering unit is connected to a third input terminal of the auxiliary power supply unit, a second output terminal of the rectifying and filtering unit is connected to a second input terminal of the starting unit,

the rectification filter unit converts alternating current input voltage input by an input end into power supply voltage of the auxiliary power supply unit and the starting unit.

12. Charging pile, characterized in that it comprises a charging control system and a charging circuit according to any of claims 1-11, the output of the charging control system being connected to the input of the charging circuit via a CAN bus.

13. The charging pile of claim 12, wherein the charging control system is configured to output a first CAN signal to control the charging circuit to enter a charging state when the charging pile needs to charge the device to be charged, and output a second CAN signal to control the charging circuit to enter a standby state when the charging pile needs to stop charging the device to be charged.