Control method and application of AC / DC input compatible circuit

Abstract

The invention discloses a control method and application of an AC / DC input compatible circuit, and the AC / DC input compatible circuit comprises a first change-over switch, and an input module, an EMC module, a PFC module and a DC bus which are connected in sequence. One end of the first change-over switch is connected with the N-line output end of the EMC module, and the other end of the first change-over switch is connected with the negative output end of the direct-current bus; the method is executed by a controller, and the control method comprises the following steps: acquiring a voltage type of an input voltage; if the voltage type is an alternating current type, controlling the first change-over switch to be switched off; or, if the voltage type is a direct current type, the first change-over switch is controlled to be switched on; and controlling the PFC module to act based on the voltage type so as to enable the compatible circuit to carry out direct current output.

Description

Technical Field

[0001] This application relates to the field of charging technology, and in particular to a control method for an AC / DC input compatible circuit and its application. Background Technology

[0002] Currently, DC transmission holds a core position in long-distance, large-capacity power transmission and renewable energy grid integration (wind power, solar power) due to its advantages such as no synchronization stability issues, low line losses (lower resistance losses than AC, no inductive / capacitive reactance losses), and strong asynchronous connection capabilities. AC transmission, on the other hand, leverages the convenience of voltage scaling via transformers to still dominate distributed power supply and traditional power grids. This complementarity between the two has spurred the demand for hybrid AC / DC power supply systems.

[0003] In related technologies, circuit structures that satisfy both AC and DC input are usually quite complex, requiring the separation of AC and DC through circuit output ports or conversion modules; at the same time, the DC input power of the circuit is only 1 / 3 of the AC input power, resulting in low power during DC input and thus poor circuit compatibility.

[0004] Therefore, how to reduce circuit complexity and improve circuit compatibility while meeting both AC and DC input requirements is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] The main objective of this application is to provide a control method for AC / DC input compatible circuits and its application, so as to achieve the purpose of switching different connection methods of the circuit by controlling the working state of the switching switch, thereby reducing circuit complexity and improving circuit compatibility.

[0006] To achieve the above objectives, this application provides a control method for an AC / DC input compatible circuit. The AC / DC input compatible circuit includes: a first switching switch and an input module, an EMC module, a PFC module, and a DC bus connected in sequence. One end of the first switching switch is connected to the neutral (N) output terminal of the EMC module, and the other end is connected to the negative output terminal of the DC bus. The method is executed by a controller, and the control method includes: obtaining the voltage type of the input voltage; if the voltage type is AC, controlling the first switching switch to open; or, if the voltage type is DC, controlling the first switching switch to close; and controlling the PFC module to operate based on the voltage type so that the compatible circuit outputs DC.

[0007] Optionally, the compatibility circuit further includes a second switching switch; the PFC module includes a rectifier bridge and a filter unit, the rectifier bridge includes three parallel bridge arms, each bridge arm having an input terminal; the filter unit includes an inductor and a capacitor, the first end of each inductor forms an input terminal of the PFC module, and the second end is connected to a corresponding bridge arm input terminal, the first end of each capacitor is connected to the first end of its corresponding inductor, and the second end is connected to the first end of the second switching switch, the second end of the second switching switch is connected to the midpoint of the DC bus; the DC bus includes a first bus capacitor and a second bus capacitor, the first end of the first bus capacitor forms the positive output terminal of the DC bus, the second end is connected to one end of the second bus capacitor to form the midpoint of the DC bus, and the second end of the second bus capacitor forms the negative output terminal of the DC bus; before controlling the PFC module to operate based on the voltage type so that the compatibility circuit outputs DC, the control method further includes: if the voltage type is AC, controlling the second switching switch to close; if the voltage type is DC, controlling the second switching switch to open.

[0008] Optionally, the compatibility circuit further includes a third switching switch, one end of which is connected to the neutral (N) output terminal of the EMC module and the other end of which is connected to the input terminal of one arm of the rectifier bridge. Before controlling the PFC module to operate based on the voltage type so that the compatibility circuit can output DC, the method further includes: if the voltage type is a three-phase AC type, controlling the third switching switch to open; if the voltage type is a single-phase AC type, controlling the third switching switch to close; if the voltage type is a DC type, controlling the third switching switch to open.

[0009] Optionally, the first switch, the second switch, and the third switch are controlled according to the following strategy: if the voltage type is three-phase AC, the first switch is controlled to open, the second switch is controlled to close, and the third switch is controlled to open in sequence; if the voltage type is single-phase AC, the first switch is controlled to open, the second switch is controlled to close, and the third switch is controlled to close in sequence; if the voltage type is DC, the second switch is controlled to open, the third switch is controlled to open, and the first switch is controlled to close in sequence.

[0010] Optionally, the compatibility circuit further includes a soft-start module connected between the EMC module and the PFC module. The soft-start module includes multiple soft-start resistors and corresponding multiple soft-start switch groups. Each soft-start switch group includes a first soft-start switch and a second soft-start switch. The first soft-start switch and the soft-start resistors are connected in series to form a soft-start branch, and the second soft-start switch is connected in parallel across the two ends of the soft-start branch. Before controlling the PFC module to operate based on the voltage type to enable the compatibility circuit to output DC, the method further includes: if the voltage type is three-phase AC, then in the control... After the third switching switch is opened, the first soft start switch and the second soft start switch of each phase are controlled to close sequentially. If the voltage type is single-phase AC, after the third switching switch is closed, the first soft start switch and the second soft start switch corresponding to the single-phase voltage are controlled to close sequentially. If the voltage type is DC, after the third switching switch is opened, the first soft start switch of each phase is first closed, and then the first switching switch and the second soft start switch of each phase are controlled to close synchronously. Alternatively, the first soft start switch of each phase, the second soft start switch of each phase, and the first switching switch are closed sequentially.

[0011] Optionally, the PFC module includes a rectifier bridge and a filter unit. The rectifier bridge includes three parallel bridge arms, each with an input terminal. The filter unit includes an inductor and a capacitor. The first end of each inductor forms an input terminal of the PFC module, and the second end is connected to a corresponding bridge arm input terminal. The first end of each capacitor is connected to the first end of its corresponding inductor, and the second end is connected to the first end of the second switching switch. The second end of the second switching switch is connected to the midpoint of the DC bus. The DC bus includes a first bus capacitor and a second bus capacitor, with the first end of the first bus capacitor forming the DC bus. The positive output terminal, the second terminal, and one end of the second bus capacitor are connected to form the midpoint of the DC bus, and the second end of the second bus capacitor forms the negative output terminal of the DC bus; the step of controlling the PFC module to operate based on the voltage type so that the compatible circuit can output DC includes: if the voltage type is DC, controlling the three arms of the rectifier bridge to synchronously generate high-frequency waves, and the waveforms of the three arms are the same and the phase is consistent; if the voltage type is single-phase AC, controlling the arm corresponding to the single-phase power to generate high-frequency waves, and controlling one of the other two arms not to generate waves and the other arm to generate power frequency waves.

[0012] Optionally, obtaining the voltage type of the input voltage includes: within a predetermined period, obtaining multiple positive polarity values ​​and multiple negative polarity values ​​of the input voltage, wherein the positive polarity value indicates that the input voltage is in a positive polarity state, and the negative polarity value indicates that the input voltage is in a negative polarity state; accumulating each of the positive polarity values ​​and each of the negative polarity values ​​to determine the polarity value of the input voltage, wherein the polarity value indicates the polarity state of the input voltage; if the polarity value is greater than or equal to a preset polarity threshold, then the voltage type of the input voltage is determined to be AC; if the polarity value is less than the preset polarity threshold, then the voltage type of the input voltage is determined to be DC.

[0013] Furthermore, to achieve the above objectives, this application also provides a power conversion module, comprising: an AC / DC input compatible circuit, and a bus capacitor, a transformer module, an output rectifier module, an output EMC module, and a DC output module sequentially connected to the output terminal of the AC / DC input compatible circuit; wherein, the AC / DC input compatible circuit includes a first switching switch and an input module, an EMC module, a PFC module, and a DC bus sequentially connected, one end of the first switching switch being connected to the neutral (N) output terminal of the EMC module and the other end being connected to the negative output terminal of the DC bus, the AC / DC input compatible circuit outputting a DC voltage based on the control method described in any embodiment of this application; the transformer module is used to transform the DC voltage; the output rectifier module is used to rectify the transformed DC voltage; the output EMC module is used to perform electromagnetic interference processing on the rectified DC voltage; and the DC output module is used to stabilize the DC voltage.

[0014] In addition, to achieve the above objectives, this application also provides a vehicle including the power conversion module described in any embodiment of this application.

[0015] Furthermore, to achieve the above objectives, this application also provides a charging system, comprising: at least two power conversion modules as described in any embodiment of this application; and a system controller, a power distribution device, and at least one charging interface; wherein the power distribution device is connected to the system controller, each of the power conversion modules, and each of the charging interfaces respectively; the system controller is connected to each of the power conversion modules respectively, and the system controller performs power distribution based on a preset strategy to control the power distribution device to output power through the charging interface.

[0016] The control method of this application uses a first switching switch to switch the connection mode of the compatible circuit according to different types of input voltage. While ensuring that the input voltage can be output at full power, it reduces the complexity of the circuit and improves the compatibility of the circuit. Attached Figure Description

[0017] Figure 1 This is one of the schematic diagrams of an AC / DC input compatible circuit structure according to an embodiment of this application; Figure 2 This is a second schematic diagram of an AC / DC input compatible circuit structure according to an embodiment of this application; Figure 3 This is a third AC / DC input compatible circuit according to an embodiment of this application; Figure 4 This is one of the flowcharts of a control method for an AC / DC input compatible circuit according to an embodiment of this application; Figure 5 This is a schematic diagram of a three-phase AC charging wave generation strategy according to an embodiment of this application; Figure 6 This is a schematic diagram of a single-phase AC charging wave generation strategy according to an embodiment of this application; Figure 7 This is a schematic diagram of a DC charging wave generation strategy according to an embodiment of this application; Figure 8 This is a schematic diagram of the power conversion module structure of an AC / DC input compatible circuit according to an embodiment of this application; Figure 9 This is a schematic diagram of the charging system according to an embodiment of this application.

[0018] In the diagram: 101, Input module; 102, EMC module; 103, Filter module; 104, Rectifier bridge; 105, Soft start module; 10, PFC module; 100, AC / DC input compatible circuit; 901, Transformer module; 902, Output rectifier module; 903, Output EMC module; 904, DC output module; 1010, Power conversion module; 1020, System controller; 1030, Power distribution device; 1040, Charging interface.

[0019] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] On-Board Charger (OBC) is a vehicle-mounted charging device used to convert external AC voltage into DC voltage that can recharge the battery. An OBC includes an AC input terminal, a soft-start circuit unit, an AC-DC converter circuit, and a DC output terminal. AC or DC voltage is connected to the AC terminal, and through fuses and EMC circuits, the system automatically identifies the AC or DC voltage using hardware sampling circuitry and software algorithms upon detection.

[0022] Currently, DC transmission holds a core position in long-distance, large-capacity power transmission and renewable energy grid integration (wind power, solar power) due to its advantages such as no synchronization stability issues, low line losses (lower resistance losses than AC, no inductive / capacitive reactance losses), and strong asynchronous connection capabilities. AC transmission, on the other hand, leverages the convenience of voltage scaling via transformers to still dominate distributed power supply and traditional power grids. This complementarity between the two has spurred the demand for hybrid AC / DC power supply systems.

[0023] Due to the fundamental differences between direct current (DC) and alternating current (AC) in energy transmission, circuit design, and component characteristics, DC current maintains a constant direction (such as the constant current output from a battery) and its voltage amplitude is stable (ideally without fluctuation). In contrast, AC current changes direction periodically with time (such as a sinusoidal AC current changing direction twice per cycle), and its voltage amplitude fluctuates according to a sine / cosine law. Furthermore, DC charges move continuously in a fixed direction, with a single energy transmission path (such as from positive to negative in a conductor). AC charges, on the other hand, undergo periodic reciprocating motion in a conductor (moving forward during the positive half-cycle and backward during the negative half-cycle), and energy is transferred through the alternating conversion of electric and magnetic fields.

[0024] Therefore, in the same circuit, the circuit structure that satisfies both AC and DC input is usually quite complex in related technologies. It is necessary to separate AC and DC through the circuit's external port or conversion module. At the same time, the DC input power of the circuit is only 1 / 3 of the AC input power, resulting in low power when DC input, which leads to poor circuit compatibility.

[0025] Based on this, embodiments of this application provide a control method for an AC / DC input compatible circuit, which achieves the purpose of switching different connection methods of the circuit by controlling the working state of the switching switch, thereby reducing circuit complexity and improving circuit compatibility.

[0026] To facilitate understanding, the AC / DC input compatible circuit will be described in detail below.

[0027] Figure 1 This is one of the schematic diagrams of an AC / DC input compatible circuit structure according to an embodiment of this application.

[0028] like Figure 1As shown, the AC / DC input compatible circuit 100 includes: a first switching switch S8 and an input module 101, an EMC module 102, a PFC module 10, and a DC bus connected in sequence. One end of the first switching switch S8 is connected to the N-line output terminal of the EMC module 102, and the other end is connected to the negative output terminal of the DC bus. The input module 101 is used to acquire the input voltage; the EMC module 102 is used to filter the input voltage; the PFC module 10 is used to perform power factor correction on the input voltage; and the first switching switch S8 is used to switch the compatible circuit between AC and DC according to the voltage type of the input voltage.

[0029] The input module 101 may be an AC input terminal corresponding to AC power. The AC input terminal may include a U-phase input terminal, a V-phase input terminal, a W-phase input terminal, and an N-phase input terminal. Correspondingly, the EMC module 102 may include a U-phase input terminal, a V-phase input terminal, a W-phase input terminal, and an N-phase input terminal to be connected to each input terminal of the input module 101 through a corresponding fuse.

[0030] After the input module 101 obtains the input voltage, it is filtered by the EMC module 102 to remove stray signals and then input to the PFC module 10 for power factor management to improve the compatible power factor.

[0031] When the input voltage is AC voltage, the AC voltage is processed by PFC module 10 and output as DC voltage, which is then output as DC through the DC bus.

[0032] In this exemplary embodiment, the DC bus may be composed of bus capacitors, which store charge to supply DC power to the downstream load.

[0033] The first switching switch S8 primarily switches on and off based on the input voltage type. Specifically, when the input voltage is AC, the first switching switch S8 is open under the control of the controller, and the AC / DC input compatible circuit is matched to the AC input. When the input voltage is DC, the first switching switch S8 is closed under the control of the controller, and the AC / DC input compatible circuit is matched to the DC input. Thus, the AC / DC input compatible circuit provided in this embodiment, through the action of the first switching switch S8, can self-match AC and DC input voltages. While ensuring full-power output of the input voltage, it reduces circuit complexity and improves circuit compatibility.

[0034] In addition, in the diagram, resistor R4 represents the load connected to the subsequent stage of the circuit.

[0035] The circuit structure and working principle of the AC / DC input compatible circuit of this embodiment will be explained in detail below with reference to the accompanying drawings.

[0036] Figure 2 This is a second schematic diagram of an AC / DC input compatible circuit according to an embodiment of this application.

[0037] like Figure 2 As shown, the AC / DC input compatible circuit may also include a soft start module 105 and a second switching switch S9. The soft start module 105 is connected between the EMC module 102 and the PFC module 10. One end of the second switching switch S9 is connected to each input terminal of the PFC module 10, and the other end is connected to the midpoint of the DC bus.

[0038] The second switching switch S9 is mainly used to optimize EMC performance. When AC power is supplied (i.e., the input voltage is three-phase AC or single-phase AC), closing the second switching switch S9 connects the capacitor in the filter unit 103 (the specific structure of the filter unit 103 can be found in the description of the following embodiments) to the midpoint of the DC bus.

[0039] In this embodiment, the first switching switch S8 and the second switching switch S9 are connected on both sides of the EMC module 102 and the output module 105 as switching switches. In this way, the EMC circuit can be reused regardless of whether it is AC input or DC input. Therefore, the circuit of this application has good anti-electromagnetic interference performance.

[0040] In this embodiment, the EMC module 102 may include a U-phase output terminal, a V-phase output terminal, and a W-phase output terminal. Correspondingly, the multiple input terminals of the PFC module 10 may include a U-phase input terminal, a V-phase input terminal, and a W-phase input terminal.

[0041] In an exemplary embodiment, each output terminal of the EMC module 102 is connected to an input terminal of the PFC module 10 via a soft start module 105. The soft start module 105 may include multiple soft start switch groups and multiple soft start resistors, with each soft start resistor corresponding to one of the multiple soft start switch groups; each soft start switch group may include a first soft start switch and a second soft start switch, with the first soft start switch and a soft start resistor connected in series to form a soft start branch, and the second soft start switch connected in parallel across the two ends of the soft start branch.

[0042] Continue to refer Figure 2 Taking the soft-start switch group and soft-start resistor connected to the U-phase output terminal of EMC module 102 as an example, the first switch S1 is the first soft-start switch in the soft-start switch group, and the second switch S2 is the second soft-start switch in the soft-start switch group. The first switch S1 and the first resistor R1 constitute a soft-start branch.

[0043] Similarly, in the soft-start switch group connected to the V-phase output terminal of EMC module 102, the third switch S3 is the first soft-start switch, the fourth switch S4 is the second soft-start switch, and the second resistor R2 is the soft-start resistor; in the soft-start switch group connected to the W-phase output terminal of EMC module 102, the fifth switch S5 is the first soft-start switch, the sixth switch S6 is the second soft-start switch, and the third resistor R3 is the soft-start resistor.

[0044] After the controller obtains the output voltage of the EMC module 102, it controls each soft-start switch and soft-start resistor in the soft-start module 105 according to a certain timing sequence to ensure that the system starts smoothly and provides stable input conditions for subsequent charging mode recognition and power conversion, avoiding circuit impact and damage.

[0045] Figure 3 This is the third AC / DC input compatible circuit according to an embodiment of this application.

[0046] like Figure 3 As shown, the PFC module 10 may include a rectifier bridge 104 and multiple filter units 103, and the rectifier bridge 104 may include multiple bridge arm input terminals corresponding one-to-one with each filter unit 103; one end of the filter unit 103 forms an input terminal of the PFC module 10, and the other end is connected to the corresponding bridge arm input terminal.

[0047] The filter unit 103 is mainly used to filter the input voltage. In this exemplary embodiment, the filter unit 103 is mainly used to suppress high-frequency noise, that is, to prevent harmonics generated by the rectifier bridge 104 from being conducted to the input side. In other words, the filter unit 103 can block the high-frequency interference signals generated by the rectifier bridge 104, preventing them from polluting the compatible circuit. The rectifier bridge 104 is used to rectify the AC input voltage into a DC voltage for output.

[0048] In an exemplary embodiment, the filter unit 103 may consist of only an inductor, that is, each bridge arm input terminal of the rectifier bridge 104 is connected to the soft start module 105 through an inductor. In this case, one end of the inductor forms an input terminal of the filter unit 103, and the other end is connected to an input terminal of a bridge arm of the rectifier bridge 104. By setting an inductor for filtering, the current waveform of the circuit can be corrected.

[0049] In an exemplary embodiment, the filter unit 103 may further include an inductor and a capacitor. In this case, the first end of each inductor forms an input terminal of the PFC module and the second end is connected to a bridge arm input terminal. The first end of each capacitor is connected to the first end of the corresponding inductor and the second end is connected to the first end of the second switching switch S9. The second end of the second switching switch S9 is connected to the midpoint of the DC bus.

[0050] Among them, reference Figure 3In the rectifier bridge circuit of the three-phase current bridge arm, the filter unit 103 may include a first inductor L1, a second inductor L2 and a third inductor L3, as well as a first capacitor C1, a second capacitor C2 and a third capacitor C3. The first end of the first inductor L1 is connected to the first end of the first capacitor C1, the first end of the second inductor L2 is connected to the first end of the second capacitor C2, the first end of the third inductor L3 is connected to the first end of the third capacitor C3, and the second ends of the first capacitor C1, the second capacitor C2 and the third capacitor C3 are all connected to the first end of the second switching switch S9. The second end of the second switching switch S9 is connected to the midpoint of the DC bus.

[0051] The inductor and capacitor constitute an LLC filter circuit. When the input voltage is AC, the capacitor can be connected to the midpoint of the DC bus by closing the second switching switch S9, which can improve the EMC performance of the compatible circuit.

[0052] The structure of the rectifier bridge will be described in detail below with reference to the attached diagram.

[0053] by Figure 3 Taking the three-phase six-arm rectifier bridge shown as an example, the rectifier bridge 104 includes a first arm, a second arm, and a third arm arranged in parallel, and each of the first arm to the third arm includes an upper half bridge and a lower half bridge; the midpoints of the first arm, the second arm, and the third arm form the input terminals of each arm; the first output terminal of the first arm, the first output terminal of the second arm, and the first output terminal of the third arm are all connected to the positive output terminal of the DC bus; the second output terminal of the first arm, the second output terminal of the second arm, and the second output terminal of the third arm are all connected to the negative output terminal of the DC bus.

[0054] The rectifier bridge 104 can be composed of switching transistors Q1-Q7, for example. The DC bus can include a first bus capacitor C4 and a second bus capacitor C5. The first terminal of the first bus capacitor C4 forms the positive output terminal of the DC bus, and the second terminal is connected to the midpoint of the DC bus, which is the second terminal of the second bus capacitor C5. The second terminal of the second bus capacitor C5 forms the negative output terminal of the DC bus. Switching transistors Q1 and Q5 form the first bridge arm, the midpoint of which is connected to the first inductor L1, and the first output terminal of the first bridge arm is connected to the positive output terminal of the DC bus. The first bridge arm consists of two output terminals: the second output terminal of the first bridge arm is connected to the negative output terminal of the DC bus; the second bridge arm is composed of switching transistors Q2 and Q3, with the midpoint of the second bridge arm connected to the second inductor L2, the first output terminal of the second bridge arm connected to the positive output terminal of the DC bus, and the second output terminal of the second bridge arm connected to the negative output terminal of the DC bus; the third bridge arm is composed of two output transistors Q3 and Q7, with the midpoint of the third bridge arm connected to the third inductor L3, the first output terminal of the third bridge arm connected to the positive output terminal of the DC bus, and the second output terminal of the third bridge arm connected to the negative output terminal of the DC bus.

[0055] When the input voltage is a three-phase AC voltage, the rectifier bridge 104 acts as a PFC (power factor correction) circuit. By controlling the timing of the switching transistors (such as generating waves with a 120° phase difference), it converts AC power into DC power and achieves a high power factor.

[0056] For example, when the input voltage is a three-phase AC voltage, the first switching switch S8 is kept open, and the first soft-start switches (switches S1, S3, and S5) are closed to put the AC / DC input circuit into a soft-start state. After sampling and software algorithm judgment of phase A voltage (Va), phase A current (Ia), phase B voltage (Vb), phase B current (Ib), phase C voltage (Vc), and phase C current (Ic) and there are no abnormalities, the second soft-start switches (switches S2, S4, and S6) are closed. At the same time, the second switching switch S9 is closed to connect the capacitive reactance unit (first capacitor C1, second capacitor C2, and third capacitor C3) to the DC bus to improve the EMC performance of the circuit. After completing the above operations, the AC / DC input compatible circuit enters the three-phase AC charging mode, and the software controls the rectifier bridge 104 to realize AC / DC conversion. At this time, the power is the maximum power.

[0057] Combination Figure 2 and Figure 3 In an exemplary embodiment, the AC / DC input compatible circuit may further include a third switching switch S7. One end of the third switching switch S7 is connected to the N-line output terminal of the EMC module 102, and the other end of the third switching switch S7 is connected to the input terminal of a bridge arm of the rectifier bridge 104. The third switching switch S7 is used to switch on and off according to whether the input voltage is a single-phase AC voltage or a three-phase AC voltage.

[0058] The third switching switch S7 is connected between the EMC module 102 and the rectifier bridge 104, and its main function is to switch the on / off state based on the AC type of the input AC voltage. Specifically, when the input voltage is a three-phase AC voltage, the third switching switch S7 is open under the control of the controller, ensuring that the three-phase signal is processed in a dedicated channel, reducing interference from the single-phase circuit to the three-phase system, improving signal purity and stability, and thus enhancing circuit compatibility. When the input voltage is a single-phase AC voltage, the third switching switch S7 is closed under the control of the controller. In this case, the system can still utilize part of the bridge arm of the three-phase PFC circuit in single-phase AC charging mode, avoiding the influence of electromagnetic interference that may be generated by the three-phase processing circuit on the single-phase AC signal, and ensuring the balance and efficiency of the AC / DC input compatible circuit.

[0059] The control method and working principle of the AC / DC input compatible circuit in this embodiment will be explained in detail below, based on the circuit structure of the AC / DC input compatible circuit described above.

[0060] Figure 4This is one of the flowcharts of a control method for an AC / DC input compatible circuit according to an embodiment of this application.

[0061] This method can be executed by the controller, such as Figure 4 As shown, the control method mainly includes the following steps: Step 410: Obtain the voltage type of the input voltage.

[0062] In this embodiment, the controller can determine the input voltage type by acquiring the voltage before or after the EMC module. The voltage type can be AC ​​or DC, and the AC voltage can specifically be three-phase AC or single-phase AC. AC / DC compatible circuits typically contain different processing paths for AC and DC. Clearly defining the voltage type ensures that the signal is correctly guided to the appropriate processing circuit, thereby avoiding signal transmission in incorrect circuit paths, reducing signal distortion and interference, and improving the circuit's compatibility with different voltage types.

[0063] Taking the input voltage acquired by the controller after processing by the EMC module as an example, after the input module 101 obtains the input voltage, the input voltage is filtered by the EMC module 102. Based on the input voltage processed by the EMC module, the controller can adjust the circuit parameters according to the actual needs of the load. Different loads may have different voltage requirements. By sampling and measuring the input voltage, it can be determined whether the current voltage meets the operating requirements of the load. If not, the component parameters in the circuit, such as the transformer turns ratio and the duty cycle of the switching transistor, can be adjusted to better match the input voltage to the load and improve the circuit's compatibility with different loads.

[0064] In an exemplary embodiment, the controller can determine the polarity value of the input voltage by detecting the polarity of the input voltage, and distinguish the voltage type of the input voltage based on the polarity value over a period of time.

[0065] In detail, in an exemplary embodiment, step 410 may specifically include the following process: Step 411: Within a predetermined period, acquire multiple positive polarity values ​​and multiple negative polarity values ​​of the input voltage, wherein the positive polarity value is used to indicate that the input voltage is in a positive polarity state, and the negative polarity value is used to indicate that the input voltage is in a negative polarity state. Step 412: Accumulate the positive and negative polarity values ​​to determine the polarity of the input voltage, whereby the polarity value is used to indicate the polarity state of the input voltage. Step 413: If the polarity value is greater than or equal to the preset polarity threshold, then the voltage type of the input voltage is determined to be AC. Step 414: If the polarity value is less than the preset polarity threshold, then the voltage type of the input voltage is determined to be DC.

[0066] Among them, the positive polarity value can also be called the instantaneous value of positive voltage, the negative polarity value can also be called the instantaneous value of negative voltage, and the polarity value can also be called the cumulative value of polarity.

[0067] By acquiring multiple positive and negative polarity values ​​of the input voltage within a predetermined period and accumulating these values, the polarity of the input voltage within the predetermined period is determined. This polarity value is then compared with preset polarity thresholds (positive threshold: 0, negative threshold: 1) to determine the voltage type of the input voltage. When the polarity value is greater than or equal to the polarity threshold, the input voltage type is determined to be alternating current (AC); when the polarity value is less than the polarity threshold, the input voltage type is determined to be direct current (DC).

[0068] For example, since the per-unit value of the positive polarity is greater than the peak per-unit value of 60V (0.3856 = 60 * 1.414 / 220), and the absolute value of the per-unit value of the negative polarity is greater than the peak per-unit value of 60V (0.3856), and negative voltage feedback only exists in AC power, and there will be at least two corresponding voltage points less than -60V in one cycle of AC power, the polarity value is obtained by summing multiple positive polarity values ​​and multiple negative polarity values.

[0069] In this embodiment, different voltage types (AC and DC) have significantly different requirements for control strategies. After determining the voltage type based on the polarity value, the control system can switch to the corresponding control mode via the first switching switch S8, thereby improving the circuit's adaptability to different voltage types and enhancing its compatibility.

[0070] Step 420: If the voltage type is AC, control the first switching switch to open; or, if the voltage type is DC, control the first switching switch to close. After determining the input voltage type, the controller can control the first switching switch S8 to close or open according to the determined voltage type to switch the AC / DC charging mode of the compatible circuit. In this embodiment, the input voltage type of the compatible circuit can be AC ​​or DC. When the voltage type is AC, the PFC module performs AC / DC conversion to output DC; when the voltage type is DC, the PFC module performs DC / DC conversion to output DC.

[0071] Specifically, when the voltage type is AC, the controller controls the first switching switch S8 to open, so that the compatible circuit operates in AC charging mode and performs AC / DC conversion; when the voltage type is DC, the controller controls the first switching switch S8 to close, so that the compatible circuit operates in DC charging mode and performs DC / DC conversion.

[0072] In a hybrid AC / DC circuit, if DC power enters the AC processing circuit, energy loss may increase due to circuit mismatch. In this embodiment, when the controller determines that the input voltage is DC, it controls the first switching switch S8 to close. In this way, DC power is transmitted and processed along a dedicated DC path, reducing unnecessary energy conversion and loss, improving the system's energy utilization efficiency, and helping to maintain the stable operation of the system.

[0073] In an exemplary embodiment, such as Figure 2 and Figure 3 As shown, the AC / DC input compatible circuit may also include a third switching switch S7. Based on this, when it is determined that the input voltage is a three-phase AC type, the controller controls the third switching switch S7 to open. When the input voltage is determined to be single-phase AC, the controller controls the third switching switch S7 to close. When the input voltage is determined to be DC, the controller controls the third switching switch S7 to open.

[0074] Continue to refer Figure 3 When the controller determines that the input voltage is AC voltage, it further determines whether the input voltage is single-phase AC voltage or three-phase AC voltage.

[0075] Three-phase AC voltage consists of three sinusoidal voltages with the same frequency, equal amplitude, and a phase difference of 120°. These three voltages are called phase A voltage, phase B voltage, and phase C voltage, respectively. Together, they constitute a three-phase AC voltage system, which can provide stable and efficient electrical energy to three-phase loads.

[0076] Single-phase AC voltage refers to a voltage in an AC circuit that changes periodically with time and has only one phase alternation. In a single-phase AC circuit, the magnitude and direction of the voltage change sinusoidally with time.

[0077] In this embodiment, when single-phase AC power is supplied (i.e., the input voltage is single-phase AC voltage), closing the third switching switch S7 avoids the influence of electromagnetic interference that may be generated by the three-phase processing circuit on the single-phase AC signal; when three-phase AC power is supplied, opening the third switching switch S7 can ensure that the three-phase signal is processed in a dedicated channel, reducing the interference of the single-phase circuit on the three-phase system, improving the purity and stability of the signal, and thus improving the compatibility of the circuit.

[0078] like Figure 2 and Figure 3 As shown, the AC / DC input compatible circuit may also include a second switching switch S9. Based on this, when it is determined that the input voltage is AC, the second switching switch S9 is controlled to close. When it is determined that the input voltage is DC, the second switching switch S9 is turned off.

[0079] Continue to refer Figure 3 In this embodiment, when the input voltage is three-phase AC, closing the second switching switch S9 allows the first capacitor C1, the second capacitor C2, and the third capacitor C3 to be connected to the DC bus to improve the circuit's EMC performance. Similarly, when the input voltage is single-phase AC (taking phase A as an example), closing the second switching switch S9 allows the first capacitor C1 to be connected to the DC bus, which also improves the circuit's EMC performance.

[0080] Furthermore, in this exemplary embodiment, the controller can specifically control the first switching switch S8, the second switching switch S9, and the third switching switch S7 according to the following strategy: If the voltage type is three-phase AC, then the first switching switch S8 is opened, the second switching switch S9 is closed, and the third switching switch S7 is opened in sequence. If the voltage type is single-phase AC, then the first switching switch S8 is opened, the second switching switch S9 is closed, and the third switching switch S7 is closed in sequence. If the voltage type is DC, then the second switch S9 is opened, the third switch S7 is opened, and the first switch S8 is closed in sequence.

[0081] The specific control process of the three switching switches will be further introduced in subsequent steps in conjunction with the startup process of the soft start module, and will not be elaborated here.

[0082] Step 430: Control the PFC module to operate based on voltage type so that the compatible circuit can output DC.

[0083] In this embodiment, if the voltage type is determined to be DC, the controller controls the three arms of the rectifier bridge to generate high-frequency waves synchronously, and the waveforms of the three arms are the same and the phases are consistent; if the voltage type is determined to be single-phase AC, the controller controls the arm corresponding to the single-phase voltage to generate high-frequency waves, and controls one of the other two arms not to generate waves while the other arm generates power frequency waves.

[0084] Furthermore, as mentioned above, the compatible circuit may include a soft-start module, and this step can be further clarified as: controlling the soft-start module and the PFC module to operate sequentially based on the voltage type so that the compatible circuit can output DC.

[0085] When the voltage type is three-phase AC, the startup process of the soft start module is as follows: the controller first controls the first soft start switch of each phase to close, so that the soft start resistor is connected to the phase voltage circuit to reduce the instantaneous current impact, and then controls the second soft start switch of each phase to close. After the second soft start switch is closed, the soft start resistor is bypassed, thereby realizing soft start.

[0086] In the case of single-phase AC, the startup process of the soft start module is as follows: the first soft start switch and the second soft start switch corresponding to the single-phase power are closed in sequence. The soft start modules connected to the other two phases without phase voltage do not require soft start operation.

[0087] The startup process of the soft start module differs from that of the AC type in DC mode.

[0088] The control method for this step will be further explained below with reference to the accompanying drawings.

[0089] In an exemplary embodiment, when the controller determines that the input voltage is a three-phase AC voltage, the controller controls the first switching switch S8 and the third switching switch S7 to open, and closes the first soft-start switch (switches S1, S3, and S5) in the soft-start module 105, so that the AC / DC input circuit enters the soft-start state. After sampling and software algorithm judgment of phase A voltage (Va), phase A current (Ia), phase B voltage (Vb), phase B current (Ib), phase C voltage (Vc), and phase C current (Ic) and there are no abnormalities, the second soft-start switch (switches S2, S4, and S6) is closed, and at the same time the second switching switch S9 is closed to connect the first capacitor C1, the second capacitor C2, and the third capacitor C3 to the DC bus to improve the EMC performance of the circuit. After completing the above operations, the AC / DC input compatible circuit enters the three-phase AC charging mode, and the controller controls the PFC module 10 to realize AC / DC conversion according to the preset timing sequence. At this time, the power of the circuit is the maximum power.

[0090] Figure 5 This is a schematic diagram of a three-phase AC charging wave generation strategy according to an embodiment of this application. Figure 5 As shown, when the input voltage is a three-phase AC charging voltage, the rectifier bridge 104 generates a wave driving timing at a certain moment when the input AC voltage is in the positive half-cycle; when the input AC is in the positive half-cycle, the three arms of the rectifier bridge 104 generate waves at a 120° angle, and at the same time, only one set of arms generates waves. Figure 5 As shown, EPWM1A corresponds to switch Q1, EPWM1B corresponds to switch Q5, EPWM2A corresponds to switch Q2, EPWM2B corresponds to switch Q6, EPWM3A corresponds to switch Q3, and EPWM3B corresponds to switch Q7.

[0091] In an exemplary embodiment, when the input voltage is a single-phase AC voltage (taking only phase A as an example), the controller controls the first switching switch S8 to open and closes the first soft-start switch S1 to put the circuit into soft-start mode. After sampling and judging by the software algorithm that there are no abnormalities in phase A voltage, phase A current, phase B voltage, phase B current, phase C voltage, and phase C current, the controller closes the second soft-start switch S2, and simultaneously closes the second switching switch S9 and the third switching switch S7. By closing the second switching switch S9, the first capacitor C1 is connected to the DC bus to improve the EMC performance of the circuit. By closing the third switching switch S7, the capacitor C1 is connected to the midpoint of the bridge arm formed by the switching transistors Q3 and Q7. After completing the above operations, the circuit enters the single-phase AC charging mode. The controller controls the PFC module 10 to realize AC / DC conversion. At this time, the power is 1 / 3 of the maximum power.

[0092] Figure 6 This is a schematic diagram of a single-phase AC charging wave generation strategy according to an embodiment of this application. Figure 6 As shown, when the input voltage is single-phase AC charging, the rectifier bridge 104 generates a wave driving timing sequence at a certain moment when the input AC voltage is in the positive half-cycle. The AC input is that at a certain moment, the rectifier bridge 104 has only one set of bridge arms (corresponding to...). Figure 3 The first bridge arm transmits high-frequency waveforms, the second bridge arm does not transmit waveforms, and the third bridge arm transmits power frequency waveforms. EPWM1A corresponds to switch Q1, EPWM1B corresponds to switch Q5, EPWM2A corresponds to switch Q2, EPWM2B corresponds to switch Q6, EPWM3A corresponds to switch Q3, and EPWM3B corresponds to switch Q7.

[0093] In an exemplary embodiment, when the input voltage is a DC voltage, the controller disconnects the second switching switch S9 and the third switching switch S7, and closes the first soft-start switch (switches S1, S3, and S5) to enter soft-start mode. After sampling the A-phase voltage, A-phase current, B-phase voltage, B-phase current, C-phase voltage, and C-phase current and determining by the software algorithm that there are no abnormalities, the controller simultaneously closes the second soft-start switch (switches S2, S4, and S6) and the first switching switch S8, or closes the second soft-start switch (switches S2, S4, and S6) first and then closes the first switching switch S8 to enter DC charging mode. The software controls the switching transistors Q1 to Q7 to achieve AC / DC conversion, and the power of the circuit is at its maximum at this time.

[0094] Figure 7 This is a schematic diagram of a DC charging wave generation strategy according to an embodiment of this application. Figure 7As shown, during three-phase AC charging, the rectifier bridge 104 generates a wave to drive the timing at a certain moment when the DC input is applied. When the DC input is applied, the three bridge arms generate high-frequency waves simultaneously. The waveforms of the three bridge arms are the same and the phases are consistent. Among them, EPWM1A corresponds to switch Q1, EPWM1B corresponds to switch Q5, EPWM2A corresponds to switch Q2, EPWM2B corresponds to switch Q6, EPWM3A corresponds to switch Q3, and EPWM3B corresponds to switch Q7.

[0095] In this embodiment, different input voltage types correspond to different circuit paths and component layouts. Once the voltage type of the input voltage is clearly defined, the circuit can transmit and process signals according to a specific path, avoiding the waste of space caused by the mixing of AC and DC signals in the circuit, thereby improving circuit compatibility.

[0096] Based on the above embodiments, this application also provides a power conversion module. Figure 8 This is a schematic diagram of a power conversion module structure according to an embodiment of this application, such as... Figure 8 As shown, the power conversion module 900 may include: the AC / DC input compatible circuit 100 described in any of the above embodiments, and a bus capacitor C6, a transformer module 901, an output rectifier module 902, an output EMC module 903 and a DC output module 904 connected in sequence at the output terminal of the AC / DC input compatible circuit 100.

[0097] The specific circuit structure and control method of the AC / DC input compatible circuit can be found in the description of the above embodiments, and will not be repeated here. It should be understood that this embodiment has the beneficial effects described in any of the above embodiments.

[0098] The transformer module 905 may be, for example, a DC / DC circuit; the DC output module 904 may include a parallel resistor Co.

[0099] After the AC / DC input compatible circuit 100 outputs DC voltage, the output ripple is smoothed by the bus capacitor C6, and the transformer module 901 transforms the DC voltage (such as step-down, step-up, isolation, etc.). After rectification by the output rectifier module 902 and noise reduction by the output EMC module 903, the DC output module 904 inputs the DC output voltage. The DC output module 904 filters the output voltage and then inputs it to the load Ro.

[0100] Based on the above embodiments, this application also provides a vehicle that includes the power conversion module described in any of the above embodiments, and correspondingly, also includes the beneficial effects described in any of the above embodiments.

[0101] Based on the above embodiments, this application also provides a charging system. Figure 9This is a schematic diagram of the charging system according to an embodiment of this application. Figure 9 As shown, the charging system may include at least two power conversion modules 1010 as described above, as well as a system controller 1020, a power distribution device 1030, and at least one charging interface 1040.

[0102] The power distribution device is connected to the system controller, each power conversion module, and each charging interface; the system controller is also connected to each power conversion module.

[0103] The system controller allocates power based on a preset strategy to control the power distribution device to output power through the charging interface.

[0104] In addition, the power conversion module 1010 is used to convert the AC power of the power grid into DC power and provide it to the charging interface 1040. The system controller 1020 is used to obtain the power demand of each charging interface 1040 and generate a scheduling command according to the connection relationship of the controllable switch in the power distribution device 1030 and the power demand. The power distribution device 1030 is used to control the opening or closing of the controllable switch according to the scheduling command so as to distribute the output power of each power conversion module to each charging interface 1040.

[0105] In one optional implementation, the charging system provided in this application is an integrated DC charging pile, with the charging interface 1040 used to connect the charging gun, which is then connected to the main unit of the charging system via a gun mount on the main body of the charging system.

[0106] In one optional implementation, the charging system provided in this application is a split-type DC charging pile. The charging system also includes multiple charging terminals. The charging interface 1040 is used to connect the charging terminals. The charging terminals are set separately from the main body of the charging system. The charging terminals are equipped with a single charging gun or dual charging guns for outputting power to electric vehicles.

[0107] It should be noted that for details not disclosed in the charging system of this embodiment, please refer to the details disclosed in the above-described power conversion module 1010 embodiment, which will not be repeated here.

[0108] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0109] Finally, it should be noted that 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.

Claims

1. A control method for an AC / DC input compatible circuit, characterized in that, The AC / DC input compatible circuit includes: a first switching switch and an input module, an EMC module, a PFC module, and a DC bus connected in sequence. One end of the first switching switch is connected to the neutral (N) output terminal of the EMC module, and the other end is connected to the negative output terminal of the DC bus. The method is executed by a controller, and the control method includes: Obtain the voltage type of the input voltage; If the voltage type is AC, the first switching switch is controlled to open; or, if the voltage type is DC, the first switching switch is controlled to close. The PFC module is controlled to operate based on the voltage type so that the compatible circuit can output DC.

2. The control method for the AC / DC input compatible circuit according to claim 1, characterized in that, The compatibility circuit also includes a second switching switch; The PFC module includes a rectifier bridge and a filter unit. The rectifier bridge includes three parallel bridge arms, each of which has an input terminal. The filter unit includes an inductor and a capacitor. The first end of each inductor forms an input terminal of the PFC module, and the second end is connected to a corresponding bridge arm input terminal. The first end of each capacitor is connected to the first end of its corresponding inductor, and the second end is connected to the first end of the second switching switch. The second end of the second switching switch is connected to the midpoint of the DC bus. The DC bus includes a first bus capacitor and a second bus capacitor. The first end of the first bus capacitor forms the positive output terminal of the DC bus, and the second end is connected to one end of the second bus capacitor to form the midpoint of the DC bus. The second end of the second bus capacitor forms the negative output terminal of the DC bus. Before controlling the PFC module to operate based on the voltage type to enable the compatible circuit to output DC, the control method further includes: If the voltage type is AC, then control the second switching switch to close; If the voltage type is DC, then the second switching switch is turned off.

3. The control method for the AC / DC input compatible circuit according to claim 2, characterized in that, The compatibility circuit also includes a third switching switch, one end of which is connected to the N-line output terminal of the EMC module and the other end is connected to the input terminal of one arm of the rectifier bridge. Before controlling the PFC module to operate based on the voltage type to enable the compatible circuit to output DC, the method further includes: If the voltage type is three-phase AC, then the third switching switch is disconnected. If the voltage type is single-phase AC, then control the third switching switch to close; If the voltage type is DC, then the third switching switch is turned off.

4. The control method for the AC / DC input compatible circuit according to claim 3, characterized in that, The first switch, the second switch, and the third switch are controlled according to the following strategy: If the voltage type is three-phase AC, then the first switching switch is controlled to open, the second switching switch is controlled to close, and the third switching switch is controlled to open in sequence. If the voltage type is single-phase AC, then the first switching switch is opened, the second switching switch is closed, and the third switching switch is closed in sequence. If the voltage type is DC, then the second switch is turned off, the third switch is turned off, and the first switch is turned on in sequence.

5. The control method for the AC / DC input compatible circuit according to claim 3, characterized in that, The compatibility circuit also includes a soft start module connected between the EMC module and the PFC module. The soft start module includes multiple soft start resistors and multiple soft start switch groups corresponding to them. The soft start switch group includes a first soft start switch and a second soft start switch. The first soft start switch and the soft start resistor are connected in series to form a soft start branch. The second soft start switch is connected in parallel to both ends of the soft start branch. Before controlling the PFC module to operate based on the voltage type to enable the compatible circuit to output DC, the method further includes: If the voltage type is three-phase AC, then after the third switching switch is opened, the first soft start switch and the second soft start switch of each phase are closed sequentially. If the voltage type is single-phase AC, then after controlling the third switching switch to close, the first soft start switch and the second soft start switch corresponding to the single-phase power are controlled to close sequentially. If the voltage type is DC, after the third switching switch is opened, the first soft start switch of each phase is closed first, and then the first switching switch and the second soft start switch of each phase are closed synchronously. Alternatively, the first soft start switch of each phase, the second soft start switch of each phase and the first switching switch are closed in sequence.

6. The control method for the AC / DC input compatible circuit according to claim 1, characterized in that, The PFC module includes a rectifier bridge and a filter unit. The rectifier bridge includes three parallel bridge arms, each of which has an input terminal. The filter unit includes an inductor and a capacitor. The first end of each inductor forms an input terminal of the PFC module, and the second end is connected to a corresponding bridge arm input terminal. The first end of each capacitor is connected to the first end of its corresponding inductor, and the second end is connected to the first end of the second switching switch. The second end of the second switching switch is connected to the midpoint of the DC bus. The DC bus includes a first bus capacitor and a second bus capacitor. The first end of the first bus capacitor forms the positive output terminal of the DC bus, and the second end is connected to one end of the second bus capacitor to form the midpoint of the DC bus. The second end of the second bus capacitor forms the negative output terminal of the DC bus. The method of controlling the PFC module to operate based on the voltage type so that the compatible circuit can output DC includes: If the voltage type is DC, then the three arms of the rectifier bridge are controlled to generate high-frequency waves synchronously, and the waveforms of the three arms are the same and the phases are consistent. If the voltage type is single-phase AC, then the bridge arm corresponding to the single-phase voltage is controlled to generate high-frequency waves, and one of the other two bridge arms is controlled not to generate waves while the other bridge arm generates power frequency waves.

7. The control method for the AC / DC input compatible circuit according to claim 1, characterized in that, The voltage type for acquiring the input voltage includes: Within a predetermined period, multiple positive polarity values ​​and multiple negative polarity values ​​of the input voltage are acquired, wherein the positive polarity values ​​are used to indicate that the input voltage is in a positive polarity state, and the negative polarity values ​​are used to indicate that the input voltage is in a negative polarity state; The polarity value of the input voltage is determined by summing the positive polarity values ​​and the negative polarity values, wherein the polarity value is used to indicate the polarity state of the input voltage. If the polarity value is greater than or equal to the preset polarity threshold, then the voltage type of the input voltage is determined to be AC. If the polarity value is less than the preset polarity threshold, then the voltage type of the input voltage is determined to be DC.

8. A power conversion module, characterized in that, The power conversion module includes: An AC / DC input compatible circuit, and a bus capacitor, a transformer module, an output rectifier module, an output EMC module and a DC output module connected in sequence at the output terminal of the AC / DC input compatible circuit; The AC / DC input compatible circuit includes a first switching switch and an input module, an EMC module, a PFC module and a DC bus connected in sequence. One end of the first switching switch is connected to the N-line output terminal of the EMC module and the other end is connected to the negative output terminal of the DC bus. The AC / DC input compatible circuit outputs DC voltage based on the control method described in any one of claims 1-7. The transformer module is used to transform the DC voltage; The output rectifier module is used to rectify the transformed DC voltage; The output EMC module is used to process electromagnetic interference in the rectified DC voltage. The DC output module is used to stabilize the DC voltage.

9. A vehicle, characterized in that, Includes the power conversion module as described in claim 8.

10. A charging system, characterized in that, include: At least two power conversion modules as described in claim 8; and, The system controller, power distribution device, and at least one charging interface; The power distribution device is connected to the system controller, each of the power conversion modules, and each of the charging interfaces, respectively. The system controller is connected to each of the power conversion modules respectively, and the system controller performs power distribution based on a preset strategy to control the power distribution device to output power through the charging interface.

Images