Dual auxiliary power supply circuit, power supply device and electric vehicle

Abstract

The application belongs to the technical field of power electronics, and provides a double auxiliary power supply circuit, a power supply device and an electric vehicle, wherein the double auxiliary power supply circuit generates a first auxiliary output based on a first input voltage through a first auxiliary power supply module; a second auxiliary power supply module generates a second auxiliary output based on a second input voltage, an output port of the first auxiliary power supply module is connected in parallel with an output port of the second auxiliary power supply module; and a first target position of a first control unit and a second target position of a second control unit are connected to make the first auxiliary output and the second auxiliary output meet a preset condition. The main inventive concept of the application is that the first target position of the first control unit and the second target position of the second control unit are connected, so that the first auxiliary power supply module and the second auxiliary power supply module can output current or power equally, and the circuit structure is simplified.

Description

Technical Field

[0001] This application belongs to the field of power electronics technology, and in particular relates to a dual auxiliary power supply circuit, a power supply device, and an electric vehicle. Background Technology

[0002] With the rise of V2G (Vehicle-to-grid) mode for electric vehicles in recent years, the demand for bidirectional charging modules has become increasingly strong. Generally, bidirectional AC / DC modules adopt a bidirectional AC / DC + isolated bidirectional DC / DC topology. For a wide output range, an additional bidirectional Buck / Boost topology is typically added. When connected to the grid, the bidirectional module operates similarly to the unidirectional power supply method, drawing power from the grid side. However, to meet off-grid start-up requirements, power must be drawn from the DC battery side. Therefore, the auxiliary power supply in off-grid mode needs to support dual-end isolated backup power supply for start-up.

[0003] However, existing auxiliary power supply startup circuits suffer from complex circuit structures and are unable to achieve equal current or equal power output. Summary of the Invention

[0004] The purpose of this application is to provide a dual auxiliary power supply circuit, a power supply device, and an electric vehicle, which aims to solve the problems of existing auxiliary power supply start-up circuits having complex circuit structures and being unable to share current or power output.

[0005] A first aspect of this application provides a dual auxiliary power supply circuit connected to a voltage conversion circuit, the dual auxiliary power supply circuit comprising:

[0006] The first auxiliary power supply module is connected to the first port of the voltage conversion circuit, and is used to receive the first input voltage and generate the first auxiliary power output based on the first input voltage;

[0007] The second auxiliary power supply module is connected to the second port of the voltage conversion circuit, and is used to receive the second input voltage and generate the second auxiliary power supply output based on the second input voltage. The output port of the first auxiliary power supply module is connected in parallel with the output port of the second auxiliary power supply module.

[0008] The first auxiliary power supply module includes a first control unit, which is used to perform feedback regulation on the output of the first auxiliary power source. The second auxiliary power supply module includes a second control unit, which is used to perform feedback regulation on the output of the second auxiliary power source.

[0009] The first target position of the first control unit and the second target position of the second control unit are connected so that the first auxiliary source output and the second auxiliary source output meet preset conditions.

[0010] In one embodiment, the first target location is the sampling output terminal of the first control unit, and the second target location is the sampling output terminal of the second control unit.

[0011] In one embodiment, the first control unit includes a first output sampling circuit, a first voltage loop control circuit, and a first optocoupler connected in sequence, wherein the first target position is the connection position between the output terminal of the first voltage loop control circuit and the first optocoupler.

[0012] The second control unit includes a second output sampling circuit, a second voltage loop control circuit, and a second optocoupler connected in sequence, wherein the second target position is the connection position between the output terminal of the second voltage loop control circuit and the second optocoupler.

[0013] In one embodiment, the first control unit includes a third optocoupler; the second control unit includes a fourth optocoupler; wherein...

[0014] The third optocoupler and the fourth optocoupler are connected in series. The first control unit and the second control unit share the third output sampling circuit and the first control unit and the second control unit share the third voltage loop control circuit.

[0015] In one embodiment, the dual auxiliary power supply circuit further includes:

[0016] The first power supply module is located between the input terminal of the first auxiliary power supply module and the first port of the voltage conversion circuit, and is used to draw power from the first power supply terminal or the second power supply terminal of the voltage conversion circuit to obtain the first input voltage.

[0017] The second power supply module is located between the input terminal of the second auxiliary power supply module and the second port of the voltage conversion circuit, and is used to draw power from the third or fourth power supply terminal of the voltage conversion circuit to obtain the second input voltage.

[0018] In one embodiment, the first port of the voltage conversion circuit is an AC port, and the voltage conversion circuit includes a first soft-start module and a first voltage conversion module connected in sequence to the AC port; wherein, the first soft-start module is used to perform soft-start processing on the AC power input to the AC port, the first voltage conversion module is a bidirectional AC-DC converter module, the first power-taking terminal is connected to the AC port, and the second power-taking terminal is connected to the DC terminal of the bidirectional AC-DC converter module.

[0019] In one embodiment, the second port of the voltage conversion circuit is a DC terminal, and the voltage conversion circuit further includes a second soft-start module and a second voltage conversion module connected in sequence to the DC terminal; wherein, the second soft-start module is used to perform soft-start processing on the DC power input to the DC terminal, the second voltage conversion module is a DC-DC conversion module, the third power-taking terminal is connected to the output terminal of the second voltage conversion module, and the fourth power-taking terminal is connected to the DC terminal.

[0020] In one embodiment, the positive terminal of the fourth power-taking terminal is connected between the soft-start switch of the second soft-start module and the positive terminal of the DC terminal, and the negative terminal of the fourth power-taking terminal is connected to the negative terminal of the DC terminal.

[0021] In one embodiment, at least one voltage drop element is included between the negative input terminal of the second auxiliary power module and the negative terminal of the third power supply terminal, and at least one voltage drop element is included between the negative input terminal of the second auxiliary power module and the negative terminal of the fourth power supply terminal, and the voltage drop difference between the negative input terminal of the second auxiliary power module and the negative terminal of the third power supply terminal is less than the voltage drop difference between the negative input terminal of the second auxiliary power module and the negative terminal of the fourth power supply terminal.

[0022] In one embodiment, the power output of the first auxiliary source or the power output of the second auxiliary source is greater than or equal to the preset required power under a first preset operating condition; and / or

[0023] The power output by the first auxiliary source and the power output by the second auxiliary source are equal under a second preset operating condition; and / or

[0024] The power output of the first auxiliary source and / or the power output of the second auxiliary source meet the target ratio of the preset required power under the third preset operating conditions.

[0025] This application also provides a power supply device, including a voltage conversion circuit and a dual auxiliary power supply circuit as described in any of the above claims; the dual auxiliary power supply circuit is connected to the voltage conversion circuit.

[0026] This application also provides an electric vehicle including a dual auxiliary power supply circuit as described in any of the preceding embodiments.

[0027] The beneficial effects of this application embodiment compared with the prior art are as follows: This application sets a first auxiliary power supply module connected to a first port of the voltage conversion circuit to receive a first input voltage and generate a first auxiliary power source output based on the first input voltage; a second auxiliary power supply module connected to a second port of the voltage conversion circuit to receive a second input voltage and generate a second auxiliary power source output based on the second input voltage; the output ports of the first and second auxiliary power supply modules are connected in parallel; furthermore, the first auxiliary power supply module includes a first control unit for feedback regulation of the first auxiliary power source output, and the second auxiliary power supply module includes a second control unit for feedback regulation of the second auxiliary power source output; a first target position of the first control unit and a second target position of the second control unit are connected to ensure that the first and second auxiliary power source outputs meet preset conditions. The main inventive concept of this application is that by setting the first target position of the first control unit and the second target position of the second control unit to be connected, the first and second auxiliary power supply modules can share current or power output. By setting the first and second auxiliary power supply modules, the voltages at different endpoints in the voltage conversion circuit can be sampled, simplifying the circuit structure. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of a dual auxiliary power supply circuit structure provided in one embodiment of this application;

[0029] Figure 2 A schematic diagram of a dual auxiliary power supply circuit structure provided in another embodiment of this application;

[0030] Figure 3 A schematic diagram of a dual auxiliary power supply circuit structure provided in another embodiment of this application;

[0031] Figure 4 A detailed schematic diagram of a dual auxiliary power supply circuit structure provided in one embodiment of this application;

[0032] Figure 5 A detailed schematic diagram of the structure of a first auxiliary power module provided in one embodiment of this application;

[0033] Figure 6 This is a detailed schematic diagram of the structure of a first auxiliary power module and a second auxiliary power module provided in one embodiment of this application. Detailed Implementation

[0034] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0035] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0036] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0037] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0038] With the increasing popularity of new energy electric vehicles in my country, the application of DC-DC modules in the charging industry is expanding. Furthermore, bidirectional DC-DC modules have gradually replaced unidirectional DC-DC modules, becoming the mainstream product in the charging industry.

[0039] With the rise of V2G (Vehicle-to-grid) mode for electric vehicles in recent years, the demand for bidirectional charging modules has become increasingly strong. Generally, bidirectional AC / DC modules adopt a bidirectional AC / DC + isolated bidirectional DC / DC topology. For a wide output range, an additional bidirectional Buck / Boost topology is typically added. When connected to the grid, the bidirectional module operates similarly to the unidirectional power supply method, drawing power from the grid side. However, to meet off-grid start-up requirements, power must be drawn from the DC battery side. Therefore, the auxiliary power supply in off-grid mode needs to support dual-end isolated backup power supply for start-up.

[0040] However, existing auxiliary power supply startup circuits suffer from complex circuit structures and poor precision.

[0041] To solve the above technical problems, refer to Figure 1 As shown, this application embodiment provides a dual auxiliary power supply circuit connected to the voltage conversion circuit 100. The dual auxiliary power supply circuit includes: a first auxiliary power supply module 10 and a second auxiliary power supply module 20.

[0042] Specifically, the first auxiliary power supply module 10 is connected to the first port S1 of the voltage conversion circuit 100. The first auxiliary power supply module 10 is used to receive the first input voltage and generate the first auxiliary power source output based on the first input voltage. The second auxiliary power supply module 20 is connected to the second port S2 of the voltage conversion circuit 100. The second auxiliary power supply module 20 is used to receive the second input voltage and generate the second auxiliary power source output based on the second input voltage. The output ports of the first auxiliary power supply module 10 and the second auxiliary power supply module 20 are connected in parallel. The first auxiliary power supply module 10 includes a first control unit, which is used to perform feedback regulation on the first auxiliary power source output. The second auxiliary power supply module 20 includes a second control unit, which is used to perform feedback regulation on the second auxiliary power source output. The first target position of the first control unit and the second target position of the second control unit are connected so that the first auxiliary power source output and the second auxiliary power source output meet preset conditions.

[0043] In this embodiment, the first auxiliary power module 10 is used to receive a first input voltage and generate a first auxiliary power output based on the first input voltage, and the second auxiliary power module 20 is used to receive a second input voltage and generate a first auxiliary power output based on the second input voltage. The first auxiliary power module 10 includes a first control unit, and the second auxiliary power module 20 includes a second control unit. The target positions of the first control unit and the second control unit are connected. It can be understood that the first target position of the first control unit and the second target position of the second control unit are connected. This operation can make the first auxiliary power output and the second auxiliary power output meet preset conditions.

[0044] In this embodiment, by connecting the first target position and the second target position, the outputs of the first auxiliary power source and the second auxiliary power source meet preset conditions. Specifically, by connecting the first target position and the second target position, the outputs of the first auxiliary power source and the second auxiliary power source meet current sharing conditions. It can be understood that, in one embodiment, the current magnitudes of the first auxiliary power source output and the second auxiliary power source output are equal. In this embodiment, by connecting the output ports VCC of the first auxiliary power module 10 and the second auxiliary power module 20 in parallel, the auxiliary power supply startup function can be realized, simplifying the circuit structure, reducing design specifications, and saving costs.

[0045] In one embodiment, the first target location is the sampling output terminal of the first control unit, and the second target location is the sampling output terminal of the second control unit.

[0046] In this embodiment, the first control unit is used to sample the voltage output of the first auxiliary power source and adjust the output of the first auxiliary power source according to the sampling result. The second control unit is used to sample the voltage output of the second auxiliary power source and adjust the output of the second auxiliary power source according to the sampling result. By setting a first target position as the sampling output terminal of the first control unit and a second target position as the sampling output terminal of the second control unit, the first control unit can adjust the output of the first auxiliary power source according to the voltage output of the first auxiliary power source and the voltage output of the second auxiliary power source, and the second control unit can adjust the output of the second auxiliary power source according to the voltage output of the first auxiliary power source and the voltage output of the second auxiliary power source. This operation can make the output of the first auxiliary power source and the output of the second auxiliary power source meet the current sharing condition, solving the problem that the existing auxiliary power supply startup circuit cannot achieve current sharing or power sharing.

[0047] In one embodiment, the first control unit includes a first output sampling circuit, a first voltage loop control circuit, and a first optocoupler connected in sequence, wherein the first target position is the connection position between the output terminal of the first voltage loop control circuit and the first optocoupler; the second control unit includes a second output sampling circuit, a second voltage loop control circuit, and a second optocoupler connected in sequence, wherein the second target position is the connection position between the output terminal of the second voltage loop control circuit and the second optocoupler.

[0048] In this embodiment, the first output sampling circuit samples the voltage output of the first auxiliary power source, and the first voltage loop control circuit adjusts the primary-side current of the first optocoupler based on the sampling result, thereby adjusting the output of the first auxiliary power source. The second output sampling circuit samples the voltage output of the second auxiliary power source, and the second voltage loop control circuit adjusts the primary-side current of the second optocoupler based on the sampling result, thereby adjusting the output of the second auxiliary power source. By setting a first target position as the connection position between the output terminal of the first voltage loop control circuit and the first optocoupler, and setting a second target position as the connection position between the output terminal of the second voltage loop control circuit and the second optocoupler, the first control unit can adjust the output of the first auxiliary power source based on the voltage output of the first auxiliary power source and the voltage output of the second auxiliary power source, and the second control unit can adjust the output of the second auxiliary power source based on the voltage output of the first auxiliary power source and the voltage output of the second auxiliary power source. This operation ensures that the outputs of the first and second auxiliary power sources meet the current sharing condition, solving the problem that existing auxiliary power supply startup circuits cannot achieve current sharing or power sharing.

[0049] In one embodiment, the first control unit includes a third optocoupler; the second control unit includes a fourth optocoupler; the third optocoupler and the fourth optocoupler are connected in series, the first control unit and the second control unit share a third output sampling circuit, and the first control unit and the second control unit share a third voltage loop control circuit.

[0050] In this embodiment, the first control unit and the second control unit can be integrated on a single board. This operation allows the first control unit and the second control unit to share the third output sampling circuit and the third voltage loop control circuit. They are directly connected in parallel using the Vz signal, which eliminates the need for one voltage loop control circuit. The third optocoupler and the fourth optocoupler share a set of voltage loop point outputs and the third voltage loop control circuit output. The two optocouplers are connected in series on the same channel, ensuring absolutely equal current flow through the primary side of the optocouplers, resulting in better performance.

[0051] In one embodiment, reference Figure 2 As shown, the dual auxiliary power supply circuit also includes: a first power supply module 30 and a second power supply module 40.

[0052] Specifically, the first power-taking module 30 is located between the input terminal of the first auxiliary power supply module 10 and the first port S1 of the voltage conversion circuit 100. The first power-taking module 30 is used to draw power from the first power-taking terminal (e.g., UA, UB, UC) or the second power-taking terminal of the voltage conversion circuit 100 to obtain the first input voltage. The second power-taking module 40 is located between the input terminal of the second auxiliary power supply module 20 and the second port S2 of the voltage conversion circuit 100. The second power-taking module 40 is used to draw power from the third or fourth power-taking terminal of the voltage conversion circuit 100 to obtain the second input voltage.

[0053] In this embodiment, the first power-taking module 30 can draw power in real time from the positive terminal Vbus+ of the first power-taking terminal (e.g., UA, UB, UC) or the second power-taking terminal of the voltage conversion circuit 100 to obtain the first input voltage. The second power-taking module 40 can draw power in real time from the positive terminal Vdc+ of the third power-taking terminal or the fourth power-taking terminal Vo+ of the voltage conversion circuit 100 to obtain the second input voltage. The first auxiliary power supply module 10 generates the first auxiliary power source output based on the first input voltage, and the second auxiliary power supply module 20 generates the second auxiliary power source output based on the second input voltage. By setting the first target position and the second target position to connect, the first auxiliary power source output and the second auxiliary power source output can achieve current sharing, solving the problem that the existing auxiliary power supply startup circuit cannot achieve current sharing or power sharing output.

[0054] In one embodiment, reference Figure 3As shown, the first port S1 of the voltage conversion circuit 100 is an AC terminal. The voltage conversion circuit 100 includes a first soft-start module 101 and a first voltage conversion module 102 connected in sequence to the AC terminal. The first soft-start module 101 is used to perform soft-start processing on the AC power input to the AC terminal. The first voltage conversion module 102 is a bidirectional AC-DC conversion module. The first power input terminal (e.g., UA, UB, UC) is connected to the AC terminal, and the second power input terminal is connected to the DC terminal of the bidirectional AC-DC conversion module. The first voltage conversion module 102 is used to convert the AC signal output by the first soft-start module 101 into a DC signal.

[0055] In this embodiment, reference Figure 3 As shown, the first auxiliary power supply module 10 draws power from a first power source (e.g., UA, UB, UC) or a second power source, and obtains a first input voltage based on the power draw result. It can be understood that the first auxiliary power supply module 10 draws power from either the first or second power source, and selects the voltage at one of the power sources as the first input voltage according to the "larger" principle. For example, when the voltage drawn from the first power source (e.g., UA, UB, UC) is greater than the voltage drawn from the second power source, power is drawn from the first power source (e.g., UA, UB, UC); conversely, power is drawn from the positive terminal Vbus+ of the second power source. For example, when the voltage conversion circuit 100 is first started, only the AC terminal has power, so power is drawn only from the AC terminal. By setting the first auxiliary power supply module 10 to draw power from different power sources, the dual auxiliary power supply circuit can be ensured to operate stably, improving the stability and accuracy of the dual auxiliary power supply circuit.

[0056] In one embodiment, reference Figure 3 As shown, the second port S2 of the voltage conversion circuit 100 is a DC terminal. The voltage conversion circuit 100 also includes a second soft-start module 104 and a second voltage conversion module 103 connected in sequence to the DC terminal. The second soft-start module 104 is used to perform soft-start processing on the DC input to the DC terminal. The second voltage conversion module 103 is a DC-DC conversion module. The third power-taking terminal is connected to the output terminal of the second voltage conversion module 103, and the fourth power-taking terminal is connected to the DC terminal. In one embodiment, the voltage conversion circuit 100 also includes a third voltage conversion module 105, which can be a resonant circuit.

[0057] In this embodiment, reference Figure 3As shown, the second auxiliary power module 20 draws power from either the third or fourth power source and obtains the second input voltage based on the power draw result. It can be understood that the second auxiliary power module 20 draws power from either the third or fourth power source and selects the voltage at one of the power sources as the second input voltage according to the "larger" principle. For example, if the voltage drawn from the positive terminal Vdc+ of the third power source is greater than the voltage drawn from the positive terminal Vo+ of the fourth power source, then power is drawn from the positive terminal Vdc+ of the third power source; conversely, power is drawn from the positive terminal Vo+ of the fourth power source. In this embodiment, by setting the first auxiliary power module 10 to draw power from different power sources, the stable operation of the dual auxiliary power supply circuit can be ensured, improving the stability and accuracy of the dual auxiliary power supply circuit.

[0058] In one embodiment, reference Figure 3 As shown, the positive terminal Vo+ of the fourth power-taking terminal is connected between the soft-start switch K1 of the second soft-start module and the positive terminal Vout+ of the DC terminal, and the negative terminal Vout- of the fourth power-taking terminal is connected to the negative terminal Vout- of the DC terminal. Specifically, in this embodiment, the second auxiliary power supply module 20 is used to draw power from the fourth power-taking terminal and obtain a second input voltage based on the power-taking result. In a preferred embodiment, the second soft-start module further includes a soft-start resistor Rt, which is connected between the soft-start switch K1 and the positive terminal Vout+ of the DC terminal. The positive terminal Vo+ of the fourth power-taking terminal is connected between the soft-start switch K1 and the soft-start resistor Rt of the second soft-start module. The second auxiliary power supply module 20 is used to draw power from the soft-start switch K1 and the soft-start resistor Rt of the second soft-start module and obtain a second input voltage based on the power-taking result. The second auxiliary power supply module 20 generates a second auxiliary power output based on the second input voltage. In one embodiment, refer to Figure 3 As shown, the second soft start module also includes a soft start switch K2, wherein the soft start switch K2 is connected in parallel with the soft start switch K1 and the soft start resistor Rt.

[0059] In one embodiment, reference Figure 4 As shown, at least one voltage drop element is included between the negative input terminal of the second auxiliary power module 20 and the negative terminal Vdc- of the third power extraction terminal, and at least one voltage drop element is included between the negative input terminal of the second auxiliary power module 20 and the negative terminal Vout- of the fourth power extraction terminal, and the voltage drop difference between the negative input terminal of the second auxiliary power module 20 and the negative terminal Vdc- of the third power extraction terminal is less than the voltage drop difference between the negative input terminal of the second auxiliary power module 20 and the negative terminal Vout- of the fourth power extraction terminal.

[0060] In this embodiment, by setting the voltage drop difference between the negative input terminal and the negative terminal Vdc- of the third power take-off terminal of the second auxiliary power module 20 to be less than the voltage drop difference between the negative input terminal and the negative terminal Vout- of the fourth power take-off terminal of the second auxiliary power module 20, that is, by using an asymmetrical arrangement of the voltage drop element between the negative input terminal and the negative terminal Vdc- of the second auxiliary power module 20 and the voltage drop element between the negative input terminal and the negative terminal Vout- of the second auxiliary power module 20, the voltage drop difference when the second auxiliary power module 20 flows back to the fourth power take-off terminal is much greater than the voltage drop when the second auxiliary power module 20 flows back to the third power take-off terminal, thereby ensuring reliable return current and ensuring that the second auxiliary power module 20 forms a loop with the voltage conversion circuit 100 when it is working, thereby ensuring the stable operation of the dual auxiliary power supply circuit.

[0061] In one embodiment, reference Figure 4 As shown, the number of voltage drop components between the negative input terminal and the negative terminal Vdc- of the third power take-off terminal of the second auxiliary power module 20 is less than the number of voltage drop components between the negative input terminal and the negative terminal Vout- of the fourth power take-off terminal of the second auxiliary power module 20. Specifically, by setting different numbers of voltage drop components, the impedance between the negative input terminal and the negative terminal Vdc- of the third power take-off terminal of the second auxiliary power module 20 is different from the impedance between the negative input terminal and the negative terminal Vout- of the fourth power take-off terminal of the second auxiliary power module 20. This ensures that the second auxiliary power module 20 forms a loop with the voltage conversion circuit 100 during operation, preventing the second auxiliary power module 20 from bypassing the voltage conversion circuit 100 during operation. In this embodiment, by setting the number of voltage drop components between the negative input terminal of the second auxiliary power module 20 and the negative terminal Vdc- of the third power take-off terminal to be less than the number of voltage drop components between the negative input terminal of the second auxiliary power module 20 and the negative terminal Vout- of the fourth power take-off terminal, reliable return current is ensured, so as to ensure that the second auxiliary power module 20 forms a loop with the voltage conversion circuit 100 when it is working, thereby ensuring the stable operation of the dual auxiliary power supply circuit.

[0062] In one embodiment, at least one voltage drop element is included between the negative input terminal of the first auxiliary power module 10 and the negative terminal Vbus- of the second power supply terminal. By including at least one voltage drop element between the negative input terminal of the first auxiliary power module 10 and the negative terminal Vbus- of the second power supply terminal, it can be ensured that the first auxiliary power module 10 forms a loop with the voltage conversion circuit 100 when it is working, thereby ensuring the stable operation of the dual auxiliary power supply circuit.

[0063] In one embodiment, the first power-taking terminal is UA, UB, UC, and the first power-taking module 30 is used to take power from the first power-taking terminal (e.g., UA, UB, UC) of the voltage conversion circuit 100 to obtain the first input voltage. In one embodiment, the first power-taking module 30 is a first diode D1 and a second diode D2. The anode of the first diode D1 is connected to the positive terminal (UA, UB, UC) of the first soft-start module 101, and the cathode of the first diode D1 is connected to the positive input terminal of the first auxiliary power supply module 10. By setting the first sampling module to the first diode D1, the three-phase AC voltage signal can be unidirectionally conducted, preventing the generated first input voltage from flowing back into the voltage conversion circuit 100. The anode of the second diode D2 is connected to the positive terminal Vbus+ of the first voltage conversion module 102, and the cathode of the second diode D2 is connected to the positive input terminal of the first auxiliary power supply module 10. Specifically, it can be understood that the second diode D2 can sample and rectify the positive terminal Vbus+ of the first voltage conversion module 102 to generate the first input voltage. At this time, the first auxiliary power supply module 10 receives the first input voltage output by the second diode D2 and generates the first auxiliary power output according to the first input voltage. By setting the first power supply module 30 to the first diode D1 and the second diode D2, the bus voltage signal can be unidirectionally conducted, preventing the generated first input voltage from flowing back into the voltage conversion circuit 100.

[0064] In one embodiment, the second power supply module 40 includes a third diode D3 and a fourth diode D4. Specifically, the third diode D3 and the fourth diode D4 are connected in parallel. The anode of the third diode D3 is connected to the output terminal Vdc+ of the second voltage conversion module 103, and the fourth diode D4 is connected to the DC terminal Vo+ of the second soft-start module 104. The cathodes of both the third diode D3 and the fourth diode D4 are connected to the positive input terminal of the second auxiliary power supply module 20. The third diode D3 and the fourth diode D4 can achieve a "larger voltage sampling" function. That is, the third diode D3 samples the voltage at the output terminal Vdc+ of the second voltage conversion module 103, and the fourth diode D4 samples the voltage at the DC terminal Vo+ of the second soft-start module 104. When the third diode D3 and the fourth diode D4 output the larger sampled voltage signal as the second input voltage to the second auxiliary power supply module 20, the smaller voltage signal is cut off. This operation allows for sampling of the voltage at different nodes in the voltage conversion circuit 100, ensuring stable operation of the dual auxiliary power supply circuit and improving its stability and accuracy.

[0065] In one embodiment, a fifth diode D5 is included between the negative input terminal of the first auxiliary power module 10 and the negative terminal Vbus- of the second power extraction terminal. Specifically, the anode of the fifth diode D5 is connected to the negative input terminal of the first auxiliary power module 10, and the cathode of the fifth diode D5 is connected to the negative terminal Vbus- of the second power extraction terminal. The fifth diode D5 is used to ensure that when the first auxiliary power module 10 is working, the negative input terminal of the first auxiliary power module 10 forms a loop with the voltage conversion module, so as not to cause the voltage conversion module to be bypassed.

[0066] In one embodiment, a sixth diode D6 is included between the negative input terminal of the second auxiliary power module 20 and the negative terminal Vdc- of the third power extraction terminal. Specifically, the anode of the sixth diode D6 is connected to the negative input terminal of the second auxiliary power module 20, and the cathode of the sixth diode D6 is connected to the output terminal Vdc- of the second voltage conversion module 103. The sixth diode D6 is used to form a loop with the voltage conversion circuit 100 when the second auxiliary power module 20 samples the output terminal Vdc+ of the second voltage conversion module 103, so as to prevent the second auxiliary power module 20 from bypassing the voltage conversion circuit 100 when it is working.

[0067] In one embodiment, the input negative terminal of the second auxiliary power module 20 and the negative terminal Vout- of the fourth power extraction terminal include a seventh diode D7 and an eighth diode D8. Specifically, the cathode of the seventh diode D7 is connected to the negative terminal Vout- of the DC terminal, the anode of the seventh diode D7 is connected to the cathode of the eighth diode D8, and the anode of the eighth diode D8 is connected to the input negative terminal of the second auxiliary power module 20. The seventh diode D7 and the eighth diode D8 are used to form a loop with the voltage conversion circuit 100 when the second auxiliary power module 20 samples Vo+ between the soft-start switch of the second soft-start module 104 and the positive terminal of the DC terminal, so as to prevent the second auxiliary power module 20 from bypassing the voltage conversion circuit 100 during operation, thereby ensuring reliable return current and stable operation of the dual auxiliary power supply circuit.

[0068] In one embodiment, reference Figure 4 , Figure 5 As shown, both the first control unit and the second control unit include, in sequence, an output sampling circuit, a voltage loop control circuit, and an optocoupler. The corresponding target position is the connection point between the output terminal of the corresponding voltage loop control circuit and the corresponding optocoupler. Taking the first control unit as an example, the first output sampling circuit includes a first resistor R1, a second resistor R2, and a fourth resistor R4; the first voltage loop control circuit includes a third resistor R3, a fifth resistor R5, a third capacitor C3, a fourth capacitor C4, and a first voltage regulator TL431; the first optocoupler includes a first optocoupler diode Z1.

[0069] For details, please refer to Figure 5 As shown, the first end of the first resistor R1 and the first end of the fourth resistor R4 are connected to the positive output terminal of the first auxiliary power supply module 10. The second end of the first resistor R1 is connected to the first end of the second resistor R2. The second end of the second resistor R2 is grounded. The second end of the third resistor R3 is connected to the second end of the first resistor R1 after being connected in series with the fourth capacitor C4. The second end of the third capacitor C3 is connected to the second end of the first resistor R1. The first end of the third capacitor C3 and the first end of the third resistor R3 are connected to the cathode of the first optocoupler Z1. The anode of the first optocoupler Z1 is connected to the second end of the fourth resistor R4. The fifth resistor R5 is connected in parallel with the first optocoupler Z1. The cathode of the first voltage regulator TL431 is connected to the cathode of the first optocoupler Z1. The anode of the first voltage regulator TL431 is grounded. The reference terminal of the first voltage regulator TL431 is connected to the first end of the second resistor R2. The feedback terminal Vz of the first auxiliary power supply module 10 is connected to the cathode of the first voltage regulator TL431.

[0070] In this embodiment, reference Figure 4 As shown, the primary side Vz1 of the first auxiliary power module 10 and the primary side Vz2 of the second auxiliary power module 20 are connected together. Only one of the control loops of the first auxiliary power module 10 and the second auxiliary power module 20 is adjusted. Following the smaller value principle, both the first auxiliary power module 10 and the second auxiliary power module 20 use DCM (Discontinuous Conduction Mode) peak current control. Therefore, when the optocoupler transmission layer ratio (CTR) is basically the same, the adjustment voltage on the secondary side can be guaranteed to be approximately the same. The peak current on the primary side is kept basically consistent in DCM mode through the inner loop of the auxiliary power supply peak current. Since the output power in discontinuous mode (DCM) depends only on the peak current when the inductance and switching frequency are the same, the power of the two auxiliary power supplies can be basically guaranteed to be consistent.

[0071] In this embodiment, the primary side Vz1 of the first auxiliary power module 10 and the primary side Vz2 of the second auxiliary power module 20 are connected together. By simply shorting the loop output, the thermal design difficulty for long-term operation under extreme high-temperature conditions is greatly reduced, changing from the original two-for-one backup mode to a redundant power parallel mode. Here, redundant power refers to the power balance not being strictly balanced due to differences in device parameters, leaving an appropriate power margin to ensure output requirements. This solves the problems of complex circuit structure and poor accuracy in existing auxiliary power supply startup circuits.

[0072] In one embodiment, reference Figure 4 As shown, the dual auxiliary power supply circuit also includes: a first capacitor module 11 and a second capacitor module 21.

[0073] Specifically, the first capacitor module 11 is disposed between the positive and negative input terminals of the first auxiliary power supply module 10; the second capacitor module 21 is disposed between the positive and negative input terminals of the second auxiliary power supply module 20. In this embodiment, the first capacitor module 11 is used to filter the first input voltage, and the second capacitor module 21 is used to filter the second input voltage. By setting the first and second filtering modules, noise signals in the first and second input voltages can be filtered out, so that the first input voltage output to the first auxiliary power supply module 10 and the second input voltage output to the second auxiliary power supply module 20 only contain the required information signals, thereby filtering out unwanted noise signals other than specific frequencies, to ensure that the first auxiliary power supply module 10 and the second auxiliary power supply module 20 can work stably.

[0074] In one embodiment, the first capacitor module 11 includes a first capacitor C1. The second capacitor module 21 includes a second capacitor C2. Specifically, the first terminal of the first capacitor C1 is connected to the positive input terminal of the first auxiliary power supply module 10, and the second terminal of the first capacitor C1 is connected to the negative input terminal of the first auxiliary power supply module 10. The first terminal of the second capacitor C2 is connected to the positive input terminal of the second auxiliary power supply module 20, and the second terminal of the second capacitor C2 is connected to the negative input terminal of the second auxiliary power supply module 20. The first capacitor C1 is used to filter the first input voltage, and the second capacitor C2 is used to filter the second input voltage.

[0075] In one embodiment, as shown in reference 6, the first control unit and the second control unit can be integrated on a single board. In this operation, the Vz signal is directly connected in parallel, which can eliminate one TL431 voltage loop circuit. The two optocouplers share a set of voltage loop point outputs, and one TL431 circuit outputs. The two optocouplers are connected in series on the same channel, which ensures that the current flowing through the primary side of the optocoupler is absolutely evenly distributed, and the effect will be better.

[0076] For details, please refer to Figure 6 As shown, the first control unit and the second control unit can be integrated on a single board. The first control unit includes a third optocoupler; the second control unit includes a fourth optocoupler. The third and fourth optocouplers are connected in series. The first control unit and the second control unit share a third output sampling circuit and a third voltage loop control circuit. Specifically, the third optocoupler includes a second optocoupler transistor Z2; the fourth optocoupler includes a third optocoupler transistor Z3; the third output sampling circuit includes a sixth resistor R6, a seventh resistor R7, and a ninth resistor R9; the third voltage loop control circuit includes a fifth capacitor C5, a sixth capacitor C6, an eighth resistor R8, a tenth resistor R10, an eleventh resistor R11, and a second voltage regulator TL431.

[0077] Specifically, the first terminal of the sixth resistor R6 and the first terminal of the ninth resistor R9 are connected to the positive output VCC of the auxiliary power module. The second terminal of the sixth resistor R6 is connected to the first terminal of the seventh resistor R7, and the second terminal of the seventh resistor R7 is grounded. The second terminal of the eighth resistor R8 is connected in series with the sixth capacitor C6 and then connected to the second terminal of the sixth resistor R6. The second terminal of the fifth capacitor C5 is connected to the second terminal of the sixth resistor R6. The first terminal of the fifth capacitor C5 and the first terminal of the eighth resistor R8 are connected to the cathode of the third optocoupler Z3. The anode of diode Z3 is connected to the cathode of the second optocoupler Z2. The anode of the second optocoupler Z2 is connected to the second terminal of the ninth resistor R9. The tenth resistor R10 is connected in parallel with the second optocoupler Z2. The eleventh resistor R11 is connected in parallel with the third optocoupler Z3. The cathode of the second voltage regulator TL431 is connected to the cathode of the third optocoupler Z3. The anode of the second voltage regulator TL431 is grounded. The reference terminal of the second voltage regulator TL431 is connected to the first terminal of the seventh resistor R7. The feedback terminal Vz of the auxiliary power supply module is connected to the cathode of the second voltage regulator TL431. By directly connecting the Vz signal in parallel, one TL431 voltage loop circuit can be eliminated. The two optocouplers share a set of voltage loop point outputs, and one TL431 circuit outputs. The two optocouplers are connected in series on the same channel, ensuring absolutely equal current flow through the primary side of the optocouplers, resulting in better performance.

[0078] In one embodiment, the power output of the first auxiliary source or the second auxiliary source is greater than or equal to the preset required power under the first preset operating conditions; and / or the power output of the first auxiliary source and the power output of the second auxiliary source are equal under the second preset operating conditions; and / or the power output of the first auxiliary source and / or the power output of the second auxiliary source meet the target ratio of the preset required power under the third preset operating conditions.

[0079] In this embodiment, the power output of either the first auxiliary source or the second auxiliary source is greater than or equal to the preset required power under the first preset operating conditions. It is understood that under the first preset operating conditions, it is sufficient for the power output of either the first auxiliary source or the second auxiliary source to be greater than or equal to the preset required power. The first preset operating conditions can be a normal temperature environment, for example, an environment with a temperature not exceeding 55°C.

[0080] In one embodiment, the power output of the first auxiliary power source and the power output of the second auxiliary power source are equal under a second preset operating condition. It is understood that when the power output of the first auxiliary power source and the power output of the second auxiliary power source are equal under the second preset operating condition, the second preset operating condition can be a transient condition, such as a power start-up process or a power stop process, or a power protection shutdown under a transient condition (within 10 seconds). Under a transient condition (within 10 seconds), the power output of the first auxiliary power module 10 or the second auxiliary power module 20 may be very low. At this time, the peak power output of the single auxiliary power supply is required to ensure the total power demand, and the cavity temperature will take a certain amount of time to decrease. Such conditions are all transient and short-term and do not need to be considered according to long-term thermal design.

[0081] In one embodiment, the power output of the first auxiliary power source and / or the power output of the second auxiliary power source meets the target ratio of the preset required power under a third preset operating condition. The third preset operating condition can be a high-temperature environment. For example, in one embodiment, the maximum total demand of the auxiliary power supply is 100W, with a minimum shutdown power requirement of 70W; the ambient temperature is 55°C, and the maximum operating chamber temperature is 85°C. Auxiliary power supply design condition 1 is to meet a parallel redundancy of 100W at 85°C, for example, considering 60W (at 85°C); condition 2 is a transient (10s) over-power capability of 100W, with a single auxiliary power supply operating at 70W continuously at 55°C. Compared to condition 1, although the long-term power of 70W is greater than 60W, the ambient temperature of 55°C is far superior to the 85°C design condition. Furthermore, in the above example, shutdown is achieved by controlling the operation of power-consuming devices, and the actual operating power is far less than 70W, resulting in lower risk.

[0082] In one embodiment, the design requirements of the first auxiliary power module 10 and the second auxiliary power module 20 may only meet one of the first preset working conditions, the second preset working conditions, or the third preset working conditions, or may meet any two of them simultaneously, or simultaneously meet the first preset working conditions, the second preset working conditions, and the third preset working conditions, in order to meet different working environment requirements.

[0083] This application embodiment also provides a power supply device, including a voltage conversion circuit 100, and further including a dual auxiliary power supply circuit as described in any of the above; the dual auxiliary power supply circuit is connected to the voltage conversion circuit 100.

[0084] This application also provides an electric vehicle including a dual auxiliary power supply circuit as described in any of the above embodiments.

[0085] In the embodiments provided in this application, it should be understood that the disclosed apparatus / terminal devices and methods can be implemented in other ways. For example, the apparatus / terminal device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.

[0086] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A dual auxiliary power supply circuit, connected to a voltage conversion circuit, for powering up the voltage conversion circuit in a bidirectional AC / DC charging module, characterized in that, The voltage conversion circuit includes a first voltage conversion module, which is a bidirectional AC-DC conversion module. The dual auxiliary power supply circuit includes: A first auxiliary power supply module is connected to the first port of the voltage conversion circuit, and is used to receive a first input voltage and generate a first auxiliary power output based on the first input voltage; the first port of the voltage conversion circuit is an AC terminal. The second auxiliary power supply module is connected to the second port of the voltage conversion circuit. It is used to receive the second input voltage and generate the second auxiliary power supply output based on the second input voltage. The output port of the first auxiliary power supply module is connected in parallel with the output port of the second auxiliary power supply module. The second port of the voltage conversion circuit is a DC terminal. The first auxiliary power supply module includes a first control unit, which is used to perform feedback regulation on the output of the first auxiliary power source. The second auxiliary power supply module includes a second control unit, which is used to perform feedback regulation on the output of the second auxiliary power source. The first control unit includes a first output sampling circuit, a first voltage loop control circuit, and a first optocoupler connected in sequence, wherein the first target position is the connection position between the output terminal of the first voltage loop control circuit and the first optocoupler; The second control unit includes a second output sampling circuit, a second voltage loop control circuit, and a second optocoupler connected in sequence, wherein the second target position is the connection position between the output terminal of the second voltage loop control circuit and the second optocoupler; The first target position of the first control unit and the second target position of the second control unit are connected. Both the first auxiliary power module and the second auxiliary power module operate in discontinuous mode and adopt peak current control so that the output of the first auxiliary power source and the output of the second auxiliary power source achieve current sharing or power sharing. The dual auxiliary power supply circuit also includes: The second power supply module is located between the input terminal of the second auxiliary power supply module and the second port of the voltage conversion circuit, and is used to draw power from the third and fourth power supply terminals of the voltage conversion circuit to obtain the second input voltage. The negative input terminal of the second auxiliary power module includes at least one voltage drop element between the negative input terminal and the negative terminal of the third power supply terminal, and the negative input terminal of the second auxiliary power module includes at least one voltage drop element between the negative input terminal and the negative terminal of the fourth power supply terminal, and the voltage drop difference between the negative input terminal and the negative terminal of the third power supply terminal is less than the voltage drop difference between the negative input terminal and the negative terminal of the fourth power supply terminal.

2. The dual auxiliary power supply circuit of claim 1, wherein, The first target position is the sampling output terminal of the first control unit, and the second target position is the sampling output terminal of the second control unit.

3. The dual auxiliary power supply circuit of claim 1, wherein, The first control unit includes a third optocoupler; the second control unit includes a fourth optocoupler; wherein, The third optocoupler and the fourth optocoupler are connected in series. The first control unit and the second control unit share the third output sampling circuit and the first control unit and the second control unit share the third voltage loop control circuit.

4. The dual auxiliary power supply circuit of claim 1, wherein, The dual auxiliary power supply circuit also includes: The first power supply module is located between the input terminal of the first auxiliary power supply module and the first port of the voltage conversion circuit, and is used to draw power from the first or second power supply terminal of the voltage conversion circuit to obtain the first input voltage.

5. The dual auxiliary power supply circuit as described in claim 4, characterized in that, The voltage conversion circuit includes a first soft-start module and a first voltage conversion module connected in sequence to the AC terminal; wherein, the first soft-start module is used to perform soft-start processing on the AC power input to the AC terminal, the first voltage conversion module is a bidirectional AC-DC converter module, the first power-taking terminal is connected to the AC terminal, and the second power-taking terminal is connected to the DC terminal of the bidirectional AC-DC converter module.

6. The dual auxiliary power supply circuit as described in claim 4, characterized in that, The voltage conversion circuit further includes a second soft-start module and a second voltage conversion module connected in sequence to the DC terminal; wherein, the second soft-start module is used to perform soft-start processing on the DC power input to the DC terminal, the second voltage conversion module is a DC-DC conversion module, the third power-taking terminal is connected to the output terminal of the second voltage conversion module, and the fourth power-taking terminal is connected to the DC terminal.

7. The dual auxiliary power supply circuit as described in claim 6, characterized in that, The positive terminal of the fourth power-taking terminal is connected between the soft-start switch of the second soft-start module and the positive terminal of the DC terminal, and the negative terminal of the fourth power-taking terminal is connected to the negative terminal of the DC terminal.

8. The dual auxiliary power supply circuit as described in claim 1, characterized in that, The power output of the first auxiliary source or the second auxiliary source is greater than or equal to the preset required power under the first preset operating conditions; and / or The power output by the first auxiliary source and the power output by the second auxiliary source are equal under the second preset operating conditions; and / or The power output of the first auxiliary source and / or the power output of the second auxiliary source meet the target ratio of the preset required power under the third preset operating conditions.

9. A power supply device, comprising a voltage conversion circuit, characterized in that, It also includes a dual auxiliary power supply circuit as described in any one of claims 1 to 8; the dual auxiliary power supply circuit is connected to the voltage conversion circuit.

10. An electric vehicle, characterized in that, Includes the dual auxiliary power supply circuit as described in any one of claims 1 to 8.

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