CN114374254B

CN114374254B - Charging circuit and charging pile

Info

Publication number: CN114374254B
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: 2024-08-09
Anticipated expiration: 2041-01-07
Also published as: CN114374254A

Abstract

The application relates to a charging circuit and a charging pile, wherein the charging circuit comprises a starting unit, an auxiliary power supply unit, a control unit and a power conversion unit, the starting unit is used for controlling the charging circuit to enter a charging state according to an input first CAN signal, the auxiliary power supply unit works in the charging state to supply power for the control unit and the power conversion unit, and the power conversion unit converts an input alternating current input voltage into a direct current output voltage and outputs the direct current output voltage under the control of the control unit; 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 provided by the embodiment of the application can simultaneously reduce the hardware cost and standby power consumption of the charging circuit, and the method can be applied to the charging pile, so that the hardware cost and 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. At present, electric vehicles are generally charged through charging piles, and the number of the charging piles needs to be increased to adapt to the charging requirement of the electric vehicles. When the charging pile is not connected with the electric automobile for charging, the charging pile is required to be in a more energy-saving standby state. The standby power of the existing charging pile is relatively high, generally between tens and hundreds of watts, and the electric energy cost consumed in standby is still high. Therefore, it is necessary to reduce standby power consumption of the charging pile to save costs.

Disclosure of Invention

In view of this, a charging circuit and a charging pile are provided, and the charging circuit according to the embodiment of the application can reduce the hardware cost and standby power consumption of the charging circuit at the same time.

In a first aspect, an embodiment of the present application provides a charging circuit including: the starting unit is connected with the 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, in the charging state, the auxiliary power supply unit works to supply power to the control unit and the power conversion unit, and the power conversion unit converts an alternating current input voltage input by the second input end of the charging circuit into a direct current output voltage under the control of the control unit and outputs the direct current output voltage through the 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 provided by the embodiment of the application, the working state of the charging circuit CAN be switched according to the signal input by the CAN bus, and the auxiliary power supply unit is completely not operated when the charging circuit is in the standby state, so that the control unit and the power conversion unit which are powered by the auxiliary power supply unit are not operated, and the standby power consumption of the charging circuit is reduced; the first CAN signal and the second CAN signal are input to the charging circuit through the CAN bus, so that a separate signal wire is not required to be added, the design complexity of the charging circuit CAN be simplified, and the influence of interference between wires is avoided; meanwhile, the cost of hardware can be saved without adding large-cost electric appliances.

Furthermore, the embodiment of the application is triggered by the control unit when the charging state is switched to the standby state, so that the starting unit CAN not work in the charging state, the power consumption is further reduced, the interference is avoided, in addition, the control unit CAN process CAN signals generally, and compared with signals in other formats, the change cost of the control unit is lower.

In a first possible implementation manner of the charging circuit according to the first aspect, a first input terminal of the starting unit is connected to a first input terminal of the charging circuit through a CAN bus, and an output terminal of the starting unit is connected to a first input terminal 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.

In a second possible implementation manner of the charging circuit according to the first possible implementation manner of the first aspect, the charging circuit further includes a switch, the switch is connected to the third output terminal of the control unit, and the switch is connected in a path of the first input terminal of the charging circuit, the starting unit, and the auxiliary power supply unit, 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 disturbed by other CAN signals during the switch disconnection.

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

After the switch is disconnected, the auxiliary power supply unit and the starting unit can not consume power, and 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 starting unit and the first input of the auxiliary power supply unit.

In this way, the flexibility of the way in which the switch is arranged can be increased.

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

In a sixth possible implementation form of the charging circuit according to any of the second to fifth possible implementation forms of the first aspect, the first CAN signal and the second CAN signal are pulse width modulated signals, the first CAN signal and the second CAN signal being 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, and 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 starting unit CAN not influence the process.

In a seventh possible implementation form of the charging circuit according to any of the second to sixth possible implementation forms 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 via a third output terminal to control the switch to remain open.

In this way, 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; in a charging state, the switch is disconnected, the starting unit does not respond to the CAN signal any more, and the starting unit and an auxiliary power supply unit connected with the starting unit are not affected by the CAN signal.

According to the first aspect and any one of the foregoing possible implementation manners of the 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, so as to obtain a rectified and filtered signal, and the isolation device is configured to convert the rectified and filtered signal into a current signal that enables the auxiliary power unit to operate.

Through the combination of filter module and isolation device, realized converting first CAN signal into the output signal of starting unit (i.e. auxiliary power unit's start signal) for CAN realize the control to charging circuit operating condition through first CAN signal, and the use of isolation device CAN avoid the interference that the electricity connection brought.

The waveform and the filter component of the first CAN signal and the parameters of the isolation device CAN be designed, so that the starting unit CAN not respond to other signals except the first CAN signal, the auxiliary power supply unit CAN work normally through the first CAN signal, and the starting unit is not interfered by other signals transmitted 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, signal transmission can be carried out through signals in other forms such as optical signals and the like in the starting unit, and interference caused by electric connection is avoided.

In a tenth possible implementation manner of the charging circuit according to the first aspect and any one of the possible implementation manners of the first aspect, 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 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 by the input end into a power supply voltage of the auxiliary power unit and the starting unit.

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

In a second aspect, an embodiment of the present application provides a charging pile comprising a charging control system, and a charging circuit according to any one of the first aspects above, an output of the charging control system being connected to an input of the charging circuit via a CAN bus.

In this way, the standby power consumption of the charging pile can be reduced, and the hardware cost of the charging pile can be saved.

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.

Through the mode, the charging pile has voltage output when the charging circuit enters a charging state, the charging pile can charge equipment to be charged, the charging pile does not have voltage output when the charging circuit enters a standby state, the charging of the equipment to be charged is stopped, and the switching of the working state of the charging pile can be realized by controlling a signal output by the charging control system.

These and other aspects of the application will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.

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 of 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 block diagram of a starting unit 301 according to an embodiment of the present application.

Fig. 6 shows an exemplary block diagram of a filter component 3011 according to an embodiment of the application.

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

Fig. 8 shows an exemplary configuration diagram of the auxiliary power unit 302 according to an embodiment of the present application.

Fig. 9 illustrates an exemplary block diagram of a drive module 3021 according to an embodiment of the present application.

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

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

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

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

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

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

Detailed Description

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

The word "exemplary" is used 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.

In addition, numerous specific details are set forth in the following description in order to provide a better illustration of the 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, well known methods, procedures, components, and circuits have not been described in detail so as not to obscure the present application.

In order to reduce 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 can comprise a control system 11, an alternating current contactor 12 and a plurality of charging modules (13-15, three are taken as examples in the drawing) connected in parallel, when the charging pile is in a standby state, the control system 11 controls the alternating current contactor 12 to be opened, and when the charging pile needs to work, the control system 11 controls the alternating current contactor 12 to be closed, so that the standby power consumption of the charging pile is reduced. However, because the ac input voltage Vin is very large, the power parameter requirement of the ac contactor 12 is relatively high, which increases the hardware cost of the charging pile; in addition, the ac contactor 12 is added, which causes a certain power consumption when it is closed, and the standby state can reduce the power consumption, but the effect of reducing the power consumption is poor in general; in addition, the control system 11 sends out a control signal to cause the ac contactor 12 to be closed, which also takes a certain time, and the ac input voltage Vin is input to the charging module 13-15 through the closed ac contactor 12, so that the charging module 13-15 works for a period of time, which usually requires more than 10S to actually start charging, so that the charging efficiency of the charging pile is reduced.

Another charge control circuit 20 is proposed in the second prior art. As shown in fig. 2. Compared with the scheme of the first prior art, an alternating current contactor is removed, and a low-voltage power supply 22 and a contactor 23 (for example, a relay switch) are newly added, wherein the contactor 23 is connected with the low-voltage power supply 22, a plurality of charging modules (24-26, three are taken as examples in the figure) and a control system 21. When the charging pile is in a standby state, the control system 21 controls the contactor 23 to be opened, and when the charging pile needs to work, the control system 21 controls the contactor 23 to be closed, so that the standby power consumption is reduced. The low-voltage power supply 22 is used for supplying power to the charging modules 24-26 through the contactor 23 so that the charging modules can be started, and compared with the scheme in the first prior art, although a high-cost alternating-current contactor is not needed, more wires are connected with the charging modules 24-26, interference exists among the wires, signal transmission is not facilitated, and circuit cost is increased; the charging modules 24-26 need a new interface to connect with the low voltage power supply 22, 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 realize the reduction of standby power consumption of the charging pile at low hardware cost.

In order to solve the technical problems, the application provides a charging circuit, and the charging circuit can simultaneously reduce the hardware cost and standby power consumption of the charging circuit.

As shown in fig. 3, the charging circuit 30 according to the embodiment of the present application 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, controller Area Network) bus may be used to transmit charging related 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 charge 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 a charging state and a standby state, respectively.

In one possible implementation, in a case where the charging pile 300 is not connected to the electric vehicle 400, the charging circuit 30 is in a standby state, saving power consumption of the charging pile 300. 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 where 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, for example, a size range of voltage and current that the electric vehicle 400 can withstand, a current power percentage, and the like. The charging control system 31 can analyze and determine whether the electric vehicle 400 needs to be charged and the voltage that the interface 32 should output according to the received parameter information.

In one possible implementation, 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 the charging state, so that the charging circuit 30 operates normally to charge the electric vehicle 400.

In one possible implementation, the charging control system 31 may determine that charging of the electric vehicle 400 is not required (e.g., the electric vehicle is already 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, thereby saving 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 an embodiment of the present application may include: the starting unit 301, the auxiliary power supply unit 302, the control unit 303 and the power conversion unit 305, 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 unit 302 operates to supply power to the control unit 303 and the power conversion unit 305, and the power conversion unit 305 converts the ac input voltage Vin input at the second input end (B end) of the charging circuit 30 into a dc output voltage Vout under the control of the control unit 303, and outputs the dc output voltage Vout through the output end (C end) of the charging circuit 30; the control unit 303 is configured to control the charging circuit 30 to enter a standby state according to a second CAN signal input from a first input terminal (a terminal) of the charging circuit 30, where the auxiliary power unit 302 stops operating.

According to the charging circuit provided by the embodiment of the application, the auxiliary power supply unit is enabled to enter the working state by the starting unit receiving the first CAN signal, and the auxiliary power supply unit supplies power to the control unit so that the control unit also works normally, so that the charging circuit enters the charging state; the control unit under normal operation receives the second CAN signal to enable the auxiliary power supply unit to enter a stop working state, and enable the charging circuit to enter 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 a standby state, so that the control unit and the power conversion unit which are 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 to the charging circuit through the CAN bus, so that a separate signal wire is not required to be added, the design complexity of the charging circuit CAN be simplified, and the influence of interference between wires is avoided; meanwhile, the cost of hardware can be saved without adding large-cost electric appliances.

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

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

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

The starting unit 301 may receive a signal first CAN signal input by the 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 unit 302 through an output end to control the auxiliary power unit 302 to start working; the auxiliary power unit 302 can enter a working state through a current signal I received by a first input end (c end), and supply power to the control unit 303 through a first output end (d end), so that the control unit 303 starts working; the auxiliary power unit 302 may further supply power to the power conversion unit 305 through a second output terminal (k terminal), and the control unit 303 may output a control signal S3 to the power conversion unit 305 through the second output terminal (i terminal), so that the power conversion unit 305 starts to operate; 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 continuously output the converted dc output voltage Vout.

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

The control unit 303 in the embodiment of the present application may receive the second CAN signal input by the CAN bus through the first input end (f end), generate the control signal S1 according to the received second CAN signal, and output the control signal S1 to the auxiliary power unit 302 through the first output end (g end), so as to control the auxiliary power unit 302 to stop working. After the auxiliary power supply unit 302 stops working, the first output end (d end) and the second output end (k end) have no signal output, and cannot supply power to the control unit 303 and the power conversion unit 305, so that 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 any more, the dc output voltage Vout is not output any more, the charging state ends, and the charging circuit 30 enters the standby state.

In this way, the startup unit 301 and the control unit 303 can respectively realize control of the charging circuit 30 into the charging state and the standby state.

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

Through the combination of filter module and isolation device, realized converting first CAN signal into the output signal (current signal I, auxiliary power unit's start-up signal) of starting unit for CAN realize the control to charging circuit operating condition through first CAN signal, and the use of isolation device CAN avoid the interference that the electricity is connected and is brought.

For example, both the first CAN signal and the second CAN signal may be CAN protocol compliant signals that may be transmitted on a CAN bus. Wherein, one end of the filter component 3011 CAN receive the first CAN signal. In one possible implementation, the first CAN signal may be, for example, a differential pulse width modulated (PWM, pulse width modulation) signal, and the filtering component 3011 may perform rectifying filtering on the received first CAN signal, and the filtered signal is output to the isolation device 3012. The isolation device 3012 may generate a current signal I from the received filtered signal and output through the other end of the isolation device 3012, i.e., the output (b-terminal) of the start-up unit 301. When the duty ratio of the first CAN signal is different, the isolation device 3012 may generate currents with different magnitudes, and the duty ratio of the first CAN signal may be preset, so that the duty ratio of the first CAN signal is different from the duty ratio of other PWM signals, and only when the received signal is the first CAN signal, the current signal I output by the isolation device 3012 CAN control the auxiliary power supply unit 302 to start working, and if the received signal is other signals, the output current signal cannot enable the auxiliary power supply unit 302 to start working.

For example, the longest sustainable time (e.g., 5 ms) of the positive pulses of the other CAN signals of the starter unit 301 CAN be input via the CAN bus during the use of the charging pile CAN be counted, and the first CAN signal is set accordingly such that the sustainable time of the positive pulses of the first CAN signal is much longer than the other CAN signals (e.g., 20 ms). On the basis, parameters of devices such as capacitance and resistance in the filter component 3011 CAN be determined, so that only a first CAN signal is input into the filter component 3011, and the output rectified and filtered signal CAN drive a light emitter of the isolation device 3012 to emit light with enough intensity, so that a light receiver of the isolation device 3012 CAN flow a current signal I with enough intensity, and the auxiliary power supply unit 302 is driven to start working; however, after other CAN signals are input to the filter component 3011 with the same parameters, the light emitter cannot emit light with sufficient intensity, so that the light receiver cannot output a current signal I capable of driving the auxiliary power unit, and the auxiliary power unit 302 cannot start to operate.

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

In one possible implementation, the signal transmitted via the CAN bus may come from the charge control system 31, or from another signal source. The initiating unit 301 may also be arranged to be able to receive a signal S0 from another signal source via a first input (a-terminal) and to respond to the signal S0. For example, when the charging circuit 30 is applied to the charging post, other signal sources that are connected to the CAN bus and CAN send signals, such as a manually controlled push button switch, may be disposed on the charging post, and if the user presses the manual switch, the manual switch CAN send a signal S0 to the first input terminal (a terminal) of the charging circuit 30. The signal S0 may control the start-up unit 301 to output the current signal I so that the auxiliary power unit 302 operates normally. The specific arrangement of the input signal of the first input terminal of the charging circuit 30 is not limited in this disclosure.

Fig. 6 shows an exemplary block diagram of a filter component 3011 according to an embodiment of the application. As shown in fig. 6, the first CAN signal may be an input signal in a differential form, the filter component 3011 may include a diode D1, a resistor R2, a resistor R3, and a capacitor C1, where 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 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 rectifying and filtering on the input differential first CAN signal, to obtain a differential filter signal S4. In one possible implementation manner, the positions of the diode D1, the resistors R1, R2, R3, and the capacitor C1 in the filter component 3011 of the embodiment of the present application may also be changed, and the filter component 3011 may also be set in other arrangements including a capacitor, a resistor, or other types of devices, which is not limited in this application, so long as the corresponding functions can be completed.

Fig. 7 shows an exemplary block diagram of an isolation device 3012 according to an embodiment of the application. As shown in fig. 7, the isolation device 3021 includes an optical coupling isolator.

For example, the isolation device 3012 may transmit electrical signals over a light medium, 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 transistor). When the isolation device 3012 inputs the signal S4 rectified and filtered by the filter 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 in the light receiver and is output by the light receiver.

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

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

Fig. 8 shows an exemplary configuration diagram of the auxiliary power unit 302 according to an embodiment of the present application. As shown in fig. 8, the auxiliary power unit 302 may include a driving module 3021 and an auxiliary power 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 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 unit 302, an output terminal (w terminal) of the driving module 3021 may be connected to an input terminal VCC of the auxiliary power module 3022, and a first output terminal (x terminal) and a second output terminal (y terminal) of the auxiliary power module 3022 may be connected to a first output terminal (d terminal) and a second output terminal (k terminal) of the auxiliary power 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 supply module 3022 according to the current signal I, where the VCC terminal of the auxiliary power supply module 3022 may supply power to the control unit 303 and the power conversion unit 305 when there is a voltage input, so that the auxiliary power supply unit 302 works normally; the driving module 3021 is further configured to stop outputting a voltage to the auxiliary power supply module 3022 according to a control signal S1 (see fig. 11) from the first output terminal (g terminal) of the control unit 303, and the VCC terminal of the auxiliary power supply module 3022 has no voltage input and cannot supply power to the control unit 303 and the power conversion unit 305, so that the auxiliary power supply unit 302 stops working.

Fig. 9 illustrates an exemplary block diagram of a drive 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), where the driving module 3021 may be further connected to a differential input voltage (e.g., rectified and filtered ac voltages bus+ and BUS "), where the positive input voltage bus+ and the negative input voltage BUS-may be respectively connected to two ends of a light receptor of the isolation device 3012 through resistors, diodes, switches, and the like, so that when the light receptor is turned on, a path is formed between the positive input voltage bus+, the light receptor, and the negative input voltage BUS-, and one end of the light receptor connected to the negative input voltage BUS-has a current signal lout.

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

In one possible implementation manner, the intensity of the light emitted by the light emitter determines the current allowed to flow in the light receiver, and the parameters of the first CAN signal may be 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 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, the driving of the auxiliary power module 3022 is achieved, the auxiliary power unit 302 starts to operate and supplies electric power (see fig. 8) to the control unit 303 and the power conversion unit 305 in fig. 4, for example, through the first output terminal (x terminal) and the second output terminal (y terminal) of the auxiliary power module 3022, 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 one possible implementation, a bias resistor R6 is further connected between the source and the gate of Q1, and after the source potential of Q1 is pulled up, the bias resistor R6 may provide a bias voltage for the NMOS transistor to maintain the on state of the NMOS transistor, so that the auxiliary power unit 302 may continuously operate.

In one possible implementation, the auxiliary power unit 302 may be deactivated by controlling the relay R5 to open. For example, the relay R5 may also be connected to the second input terminal (h terminal) of the auxiliary power unit 302 to receive the control signal S1 (see fig. 10) output by the control unit 303. The relay R5 may be set to remain closed when the control signal S1 is not received. The relay R5 may be opened under the control of the control signal S1. When R5 is turned off, no current flows between the drain and the source of the NMOS transistor, the potential of VCC terminal (i.e., the input terminal of the auxiliary power module 3022) connected to the source of Q1 decreases, and the auxiliary power module 3022 cannot be driven, so that the auxiliary power unit 302 stops working. Since the auxiliary power supply unit 302 no longer supplies power to the control unit 303 and the power conversion unit 305 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 ceases to operate, the relay R5 may resume the closed state, enabling the auxiliary power unit 302 to operate again upon receipt of the current signal I.

It should be understood by those skilled in the art that the above-described structure of the auxiliary power unit 302 is only one possible arrangement, and the possible arrangement of the auxiliary power unit 302 may be set to be driven by a control signal, for example, the driving module 3021 may be enabled to generate the control signal according to the current signal I, the control signal drives the auxiliary power module 3022 to enable the auxiliary power unit 302 to operate, and so on, so long as the corresponding function can be achieved, which is not described herein.

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

Fig. 10 shows an exemplary configuration diagram of the charging circuit 30 according to the embodiment of the present application. As shown in fig. 10, the charging circuit 30 according to the embodiment of the present application further includes a rectifying and filtering unit 304, where an input end (m-end) of the rectifying and filtering unit 304 is connected to a second input end (B-end) of the charging circuit 30, a first output end (o-end) of the rectifying and filtering unit 304 is connected to a third input end (p-end) of the auxiliary power unit 302, a second output end (r-end) of the rectifying and filtering unit 304 is connected to a second input end (s-end) of the starting unit 301, and the rectifying and filtering unit 304 converts an ac input voltage Vin input by the input end into a power supply voltage of the auxiliary power unit 302 and the starting unit 301. In this way, the auxiliary power supply unit and the starting unit can be supplied with the power 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 to the auxiliary power supply unit 302 and the starting unit 301, so that the power conversion unit 305 can complete the acquisition and output of 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 one possible implementation, after the auxiliary power unit 302 is operated, 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 through the received signals. In this case, in order to further avoid that the start-up unit 301 responds to other signals transmitted on the CAN bus, the generated current signal causes unnecessary power consumption of diodes, resistors, etc. of the auxiliary power supply unit 302, and the embodiments of the present application propose possible implementation manners as shown in fig. 11-13.

In a possible implementation, the charging circuit 30 further includes a switch K1, where the switch K1 is connected to the third output terminal (t terminal) of the control unit 303, and the switch K1 is connected in a path of the first input terminal (a terminal) of the charging circuit 30, the starting unit 301, and the auxiliary power unit 302, 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 path disconnection, and the units on the path are not disturbed by other CAN signals during the switch disconnection.

As CAN be seen from the above description, in the embodiment of the present application, the signal input from the CAN bus is received by the start-up unit 301, and the current signal I is input to the auxiliary power unit 302, and three phases are required to be undergone: a first stage, the signal is input to the filter component 3011; a 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 may be provided between paths corresponding to any one of the above stages. By turning off 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, nor interfering with the operation of the control unit 303.

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

For example, the switch K1 may be disposed between paths corresponding to the first stage. In this case, when K1 is off, the signal transmitted on the CAN bus does not enter the filter component 3011, and therefore the subsequent second stage and third stage are not necessarily reached, so that the starter unit 301 does not have a 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 the devices such as the resistor and the capacitor in the starting unit 301 do not consume power, so that the power consumption of the charging circuit 30 can be further reduced.

In a possible implementation, 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 (t terminal) to control the switch K1 to remain open.

For example, the normally closed switch K1 may remain closed without signal control. In this way, after the charging circuit 30 enters the standby state, the control unit 303 stops operating, so that the switch K1 is not controlled by the signal and returns to the closed state, and the startup unit 301 CAN operate normally when a new first CAN signal is input to the CAN bus.

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 be conveniently charged. In a charging state, the switch is disconnected, the starting unit does not respond to the CAN signal any more, and the starting unit and an auxiliary power supply unit connected with the starting unit are not affected 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 application. In one possible implementation, the switch K1 is connected inside the starting unit 301.

For example, the switch K1 may be disposed between paths corresponding to the second stage. In this case, when K1 is off, the filtered signal output by the filter component 3011 does not enter the isolation device 3012, and thus 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 some of the devices such as the resistor and the capacitor in the starting 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 provided in the filter component 3011. It should be understood by those skilled in the art that the switch K1 should be arranged in more than the above method, and the present application is not limited thereto, as long as the corresponding function can be accomplished.

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

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

In one possible implementation, the first CAN signal and the second CAN signal are pulse width modulated signals, the first CAN signal and the second CAN signal being the same or different. For example, when the charging circuit does not include a switch, the first CAN signal may be set to be different from the second CAN signal, and when the charging circuit includes a switch, the first CAN signal may be set to be the same as (or different from) the second CAN signal, so that the control unit may control the auxiliary power unit to be turned on according to the received second CAN signal, without the startup unit affecting this 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 starting unit 301, the current signal output by the starting unit 301 cannot make the NMOS transistor Q1 of the driving module 3021 conductive. In this case, the control unit 303 may control the auxiliary power unit 302 to be turned on according to the received second CAN signal, without the start-up unit 301 affecting this process.

In a possible implementation, when the charging circuit 30 includes the switch K1, the first CAN signal may be set to be the same as the second CAN signal, or the first CAN signal may be set to be different from the second CAN signal, because, in the charging state, the control unit 303 may control the switch K1 to be turned off, so that the power-up unit 301 does not affect the operation state of the auxiliary power unit 302 no matter what signal is received. In this case, the control unit 303 may control the auxiliary power unit 302 to be turned on according to the received second CAN signal, without the start-up unit 301 affecting this process.

The embodiment of the application also provides a charging pile 300, wherein the charging pile 300 comprises a charging control system 31 and a charging circuit 30 according to the embodiment of the application, and an output end of the charging control system 31 is connected with an input end of the charging circuit 30 through a CAN bus. In this way, the standby power consumption of the charging pile can be reduced, and the hardware cost of the charging pile can be saved.

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

In one possible implementation, the charging pile 300 may further be provided with an interface capable of making a physical connection (e.g., CAN bus) with an electric vehicle. When the electric vehicle and the charging pile 300 are in a connection state, the charging control system 31 CAN exchange data with the battery management system of the electric vehicle through the CAN bus, and receive charging parameter information transmitted by the battery management system of the electric vehicle, an instruction for starting charging, an instruction for stopping charging, and the like. Upon receiving an instruction to start charging, the charging control system may send a first CAN signal to the charging circuit 30. Upon receiving an instruction to stop charging, the charging control system 31 may issue a second CAN signal to the charging circuit 30.

In one possible implementation, the charging pile 300 may also be provided with a manually controlled button, or may also be provided with a display device including a control, where the button and the display device may be connected to the charging control system 31, and when the electric vehicle is in a connected state with the charging pile, 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 one possible implementation, 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, and the plurality of charging circuits 61-6n may be connected in parallel, and each charging circuit may have the same structure as one possible configuration of the charging circuit 30. The output terminal of the charging control system 31 may be connected to the first input terminal (A1 terminal-An terminal) of each charging circuit through a 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 with the charging pile.

Fig. 15 illustrates an exemplary workflow of a charging stake 300 according to an embodiment of the application. The charging circuit 62, which is one of the plurality of charging circuits, is described below 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 to start charging, the charging control system 31 may output a first CAN signal to the charging circuit 62. The starting unit of the charging circuit 62 may control the auxiliary power unit of the charging circuit 62 to work normally according to the received first CAN signal.

The instruction for starting charging can be sent by an electric automobile battery management system connected with the charging pile, or can be triggered by the button on the charging pile or the 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 a standby state, the control unit of the charging circuit 62 is also in a deactivated state, and the control unit does not respond to the first CAN signal.

After the auxiliary power unit of the charging circuit 62 works normally, the task of the starting unit of the charging circuit 62 is completed, and under the condition that the first input end of the starting unit is connected with the normally closed switch, the control unit of the charging circuit 62 can control the switch to be kept off through outputting a control signal, so that other signals (such as signals including charging related parameter information) cannot be input into the filter component of the starting unit, the filter component does not have signal output, and current which can affect the working state of the auxiliary power unit connected with the isolation device cannot be generated in the isolation device, so that the working state of the control unit supplied by the auxiliary power unit is prevented from being affected. In this way, the charging control system is not affected by the starting unit when it needs to exchange signals with other devices (e.g. control unit) of the charging circuit via the CAN bus.

The auxiliary power supply unit of the charging circuit 62 supplies power to the control unit and the power conversion unit of the charging circuit 62 after normal operation, 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 direct current is output at the output terminal of the charging circuit 62 and used for charging an electric device 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 a charged state and the charging control system 600 receives an instruction to stop charging. The control unit may output a control signal to control the auxiliary power 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 the opening of a relay in the auxiliary power supply unit, which relay can be connected in the path of the supply voltage side and the output side of the auxiliary power supply unit.

In one possible implementation, the second CAN signal is also input to the starter unit of the charging circuit 62, but since the starter unit is disconnected from the charging control system 600 by the switch, the starter 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, no power is 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 after the control unit stops working and returns to the closed state. The charging circuit 62 enters a standby state.

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

The remaining charging circuitry of the charging stake 300 can perform the same function as the charging circuitry 62.

It will be appreciated by those skilled in the art that the workflow of the charge control circuit 60 shown in fig. 15 is merely exemplary, and the workflow 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 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 will also be 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, such as circuits or ASIC (Application SPECIFIC INTEGRATED circuits) which perform the corresponding functions or acts, or combinations of hardware and software, such as firmware and the like.

Although the invention is described herein 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 study of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the "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.

The foregoing description of embodiments of the application has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the improvement of 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 starting unit, the auxiliary power supply unit, the control unit and the power conversion unit are respectively connected with the 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, in the charging state, the starting unit generates a current signal according to the first CAN signal and outputs the current signal to the auxiliary power supply unit, the auxiliary power supply unit is controlled to work through the current signal so as to supply power for the control unit and the power conversion unit, and the power conversion unit converts alternating current input voltage input by the 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 the 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, wherein the charging circuit comprises a capacitor,

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;

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.

3. The charging circuit of claim 2, further comprising a switch connected to the third output of the control unit, and the switch is connected in a path of the first input of the charging circuit, the starting unit, and the auxiliary power unit, the path being open when the switch is open.

4. A charging circuit according to claim 3, wherein the switch is connected between the first input of the start-up unit and the first input of the charging circuit.

5. A charging circuit according to claim 3, wherein the switch is connected between the output of the start-up unit and the first input of the auxiliary power supply unit.

6. A charging circuit according to claim 3, wherein the switch is connected inside the starting unit.

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

8. A charging circuit according to any one of claims 3-6, wherein the switch is a normally closed switch, and wherein in the charged state the control unit is further adapted to output a control signal via the third output terminal for controlling the switch to remain open.

9. The charging circuit of claim 1, wherein the power-on unit comprises a filter assembly and an isolation device, one end of the filter assembly is connected with the first input end of the power-on unit, the other end of the filter assembly is connected with one end of the isolation device, the other end of the isolation device is connected with the output end of the power-on unit,

The filter component 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 for enabling 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 of claim 1, further comprising a rectifying and filtering unit, wherein an input of the rectifying and filtering unit is connected to the second input of the charging circuit, a first output of the rectifying and filtering unit is connected to the third input of the auxiliary power unit, a second output of the rectifying and filtering unit is connected to the second input of the starter unit,

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

12. A charging pile, characterized in that it comprises a charging control system and a charging circuit according to any one 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 according to 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 in a case where 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 in a case where the charging pile needs to stop charging the device to be charged.