Single-phase and three-phase compatible onboard charger

Abstract

Disclosed in the present invention is a single-phase and three-phase compatible onboard charger, comprising an AC power supply input end, an EMC filter device, a three-phase rectifier, a controller, a first switch K 1 connected in series between the EMC filter device and an AC power supply, and a second switch K 2 connected in series between the EMC filter device and the three-phase rectifier. The present invention controls the opening and closing of the two switches, thereby achieving the single-phase and three-phase compatible operation. In addition, a unified filter circuit is used during the single-phase and three-phase operation, thereby reducing the number of filter devices and the number of switching devices, and further reducing the size and cost of a system. In the present invention, the working principle of a circuit is simple, the cost of controlling the system is low, and the single-phase and three-phase compatible operation is achieved simply by means of switching of relay switches; moreover, the design of an input filter is simplified, and the same filter device is used during the single-phase and three-phase operation, without adding an additional component, thereby reducing the cost and size of the system.

Description

A vehicle charger compatible with both single-phase and three-phase power supply Technical Field

[0001] This invention relates to the field of electric vehicle charging technology, and more particularly to an on-board charger compatible with both single-phase and three-phase charging. Background Technology

[0002] my country's electric vehicle industry is developing rapidly, and charging technology is one of the key issues affecting the driving range of electric vehicles, making it a hot research topic within the industry. Currently, most on-board chargers are single-phase AC input. However, with the increase in power battery capacity, charging speed is limited by single-phase input. Therefore, the requirements for on-board chargers are gradually shifting from single-phase input to three-phase input. However, as a means of transportation, if electric vehicles can only operate with a single power source (single-phase or three-phase input), it will limit their further promotion and use. To achieve flexible charging and improve convenience for electric vehicles, higher requirements are placed on the existing on-board charger topology: it must have AC-DC conversion capabilities compatible with both single-phase and three-phase input; at the same time, it must minimize the manufacturing cost of on-board chargers and improve their operating efficiency.

[0003] When charging electric vehicles, the charging gun or plug connects directly to the power interface, making the connection simple and convenient. Most currently used on-board chargers only have a three-phase charging circuit for use with corresponding charging stations; or they only have a single-phase charging circuit for direct connection to household power. Current on-board chargers compatible with both single-phase and three-phase operation determine whether to operate on single-phase or three-phase based on the input voltage or current sampling signal, switching between single-phase and three-phase circuits via relay switching. However, the input filters for single-phase and three-phase operation are separate, requiring separate filter design for each operating condition. In summary, there is significant room for optimization in both system cost and complexity of current on-board chargers compatible with both single-phase and three-phase operation.

[0004] Chinese patent document CN116231705A discloses a 20kW bidirectional single-phase / three-phase compatible off-board DC charging module for electric vehicles. In this patent, when single-phase or three-phase power passes through the input soft-start circuit, the input voltage sampling circuit collects the input voltage signal and transmits it to the DSP control circuit to determine whether the input is single-phase or three-phase, thereby controlling the relay in the soft-start circuit to achieve single-phase and three-phase compatible operation of the charging module. In this solution, different filter circuits are used for single-phase and three-phase inputs, requiring separate filter designs for single-phase and three-phase operation. Furthermore, the input common-mode inductor uses four windings, resulting in higher system cost and a larger charger module size.

[0005] Chinese patent document CN113071436B discloses a seven-in-one high-voltage integrated system circuit structure and its operating method for electric vehicles. This patent simplifies the overall circuit by reusing components in different modes, integrating seven functions: a motor controller, a single-phase slow charger, a three-phase fast charger, a single-phase power inverter, a three-phase power inverter, a high-power bidirectional DC / DC converter, and a low-power bidirectional DC / DC converter. The integrated circuit significantly reduces the number of power switches and various energy storage components, greatly reducing the manufacturing cost of electric vehicles. In this scheme, the front-stage PFC operates as a bridgeless totem-pole PFC circuit in single-phase operation. The extra set of bridge arms in the three-phase bridge arms is not used for interleaved parallel connection, resulting in a large input current ripple, which is detrimental to the design of the input filter.

[0006] Chinese patent document CN107947309B discloses a charging control circuit compatible with single-phase and three-phase AC power supplies. This patent achieves compatible operation of single-phase and three-phase circuits through a combination of two relay switches, simultaneously completing single-phase and three-phase compatible operation with fewer power devices, while maintaining a high power output even when using single-phase AC power. The proposed charging module has the advantages of simple circuit structure, reliable operation, and low cost. However, this patent does not consider the design of an input filter, making it difficult to directly apply in practical engineering.

[0007] In summary, in existing topologies that are compatible with both single-phase and three-phase operation, the input filters for single-phase and three-phase operation are separate. Therefore, this increases the system cost, enlarges the size of the on-board charger, and hinders further efficiency improvements. Summary of the Invention

[0008] To address the aforementioned deficiencies in the existing technology, this invention proposes a vehicle charger that is compatible with both single-phase and three-phase operation.

[0009] The technical solution adopted in this invention is to design a vehicle charger compatible with both single-phase and three-phase power, including an AC power input terminal, an EMC filter and a three-phase rectifier, a controller, a first switch K1 connected in series between the EMC filter and the AC power, and a second switch K2 connected in series between the EMC filter and the three-phase rectifier. The controller is used to control the operation of the first switch K1 and the second switch K2 when the AC power is three-phase, so that the three-phase power is delivered to the three-phase lines of the three-phase rectifier through the three-phase lines in the EMC filter for three-phase rectification. When the AC power is single-phase, the controller controls the operation of the first switch K1 and the second switch K2, so that the single-phase power is delivered to one phase line of the three-phase rectifier through one phase line in the EMC filter for single-phase rectification, or delivered to two phase lines of the three-phase rectifier for single-phase interleaved parallel rectification.

[0010] Preferably, the first switch K1 includes a first fixed terminal, a first moving terminal, and a second moving terminal, and the second switch K2 includes a second fixed terminal, a third moving terminal, and a fourth moving terminal; the first fixed terminal is connected to one phase of the EMC filter device, the first moving terminal is connected to one phase of the AC power input terminal that corresponds to the phase connected to the first fixed terminal, and the second moving terminal is connected to the neutral line N of the AC power input terminal; the third moving terminal and the fourth moving terminal are respectively connected to two phases of the EMC filter device that are not connected to the first fixed terminal, and the second fixed terminal is connected to one phase of the three-phase rectifier that corresponds to the third moving terminal and the fourth moving terminal.

[0011] Preferably, when the AC power supply is three-phase, the first fixed terminal is connected to the first moving terminal, the first fixed terminal is disconnected from the second moving terminal, the second fixed terminal is connected to the third moving terminal when the phase connected to the second fixed terminal is the same as the phase connected to the third moving terminal, the second fixed terminal is disconnected from the fourth moving terminal, the second fixed terminal is connected to the fourth moving terminal when the phase connected to the second fixed terminal is the same as the phase connected to the fourth moving terminal, and the second fixed terminal is disconnected from the third moving terminal, so as to perform the three-phase rectification; when the AC power supply is In single-phase electricity, the first fixed terminal is disconnected from the first moving terminal, the first fixed terminal is connected to the second moving terminal, the second fixed terminal is connected to the moving terminal of the third or fourth moving terminal that is connected to the same phase as the second fixed terminal, and the moving terminals that are connected to the second fixed terminal but not to the same phase as the second fixed terminal are disconnected, so as to perform single-phase rectification; or the second fixed terminal is connected to the moving terminal of the third or fourth moving terminal that is connected to the same phase as the second fixed terminal, and the moving terminals that are connected to the same phase as the second fixed terminal are disconnected, so as to perform single-phase interleaved parallel rectification.

[0012] Preferably, the AC power input terminal includes phase A line L. A1 Phase B line L B1 C-phase line L C1 And the neutral line N, the EMC filter device includes a filter input A phase L A2 Filtered input B phase L B2 Filtered input C phase L C2 Filtered output A phase L A3 Filtered output B phase L B3 and filter output C phase L C3 The three-phase rectifier includes rectifier A phase L. A4 1. Rectifier B-phase L B4 rectifier C-phase L C4 .

[0013] Optionally, the first fixed terminal is connected to the filter input C phase L of the EMC filter device.C2 The first moving end is connected to the C phase line L in the AC power supply. C1 The A phase line L A1 Connect the filter input A phase L A2 The B phase line L B1 Connect the filter input B phase L B2 The third moving terminal is connected to the filter output phase A L of the EMC filter device. A3 The fourth moving terminal is connected to the filter output phase B of the EMC filter device. B3 The second fixed terminal is connected to the rectifier phase B L in the three-phase rectifier. B4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output C-phase L C3 Connect the rectifier C phase L C4 Alternatively, the third moving terminal can be connected to the filter output phase A of the EMC filter device. A3 The fourth moving terminal is connected to the filter output phase B of the EMC filter device. B3 The second fixed terminal is connected to the rectifier phase A L in the three-phase rectifier. A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 The filtered output C-phase L C3 Connect the rectifier C phase L C4 .

[0014] Optionally, the first fixed terminal is connected to the filter input phase B L of the EMC filter device. B2 The first moving end is connected to phase B, line L, of the AC power supply. B1 The A phase line L A1 Connect the filter input A phase L A2 The C-phase line L C1 Connect the filter input C phase L C2 The third moving terminal is connected to the filter output phase A L of the EMC filter device. A3 The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3 The second fixed terminal is connected to the rectifier C phase L in the three-phase rectifier. C4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 Alternatively, the third moving terminal can be connected to the filter output phase A of the EMC filter device. A3The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3 The second fixed terminal is connected to the rectifier phase A L in the three-phase rectifier. A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 The filtered output C-phase L C3 Connect the rectifier C phase L C4 .

[0015] Optionally, the first fixed terminal is connected to the filter input phase A L of the EMC filter device. A2 The first moving end is connected to phase A, line L in the AC power supply. A1 The B phase line L B1 Connect the filter input B phase L B2 The C-phase line L C1 Connect the filter input C phase L C2 The third moving terminal is connected to the filter output phase B of the EMC filter device. B3 The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3 The second fixed terminal is connected to the rectifier C phase L in the three-phase rectifier. C4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 Alternatively, the third moving terminal can be connected to the filter output phase B of the EMC filter device. B3 The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3 The second fixed terminal is connected to the rectifier phase B L in the three-phase rectifier. B4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output C-phase L C3 Connect the rectifier C phase L C4 .

[0016] Preferably, both the first switch K1 and the second switch K2 use a single-pole double-throw relay; or the first switch K1 uses a combination of two single-pole single-throw relays, with one contact of the two single-pole single-throw relays connected in parallel as the first fixed terminal, and the other contacts not connected in parallel as the first moving terminal and the second moving terminal, respectively; or the second switch K2 uses a combination of two single-pole single-throw relays, with one contact of the two single-pole single-throw relays connected in parallel as the second fixed terminal, and the other contacts not connected in parallel as the third moving terminal and the fourth moving terminal, respectively.

[0017] Preferably, the EMC filtering device includes a first filter, a first common-mode inductor, a second filter, a second common-mode inductor, and a third filter connected in sequence.

[0018] Preferably, the first common-mode inductor and the second common-mode inductor have the same structure, each including an integrated magnetic core and three windings wound on the integrated magnetic core, the three windings being connected in series one by one in the three phase lines.

[0019] Preferably, the position of the first switch K1 also includes integration at the input terminal of the EMC filter device, and the second switch K2 is connected in series on the input side of the first filter, or in series between the first filter and the first common-mode inductor, or in series between the first common-mode inductor and the second filter, or installed between two sets of filter capacitors in the second filter, or in series between the second filter and the second common-mode inductor, or in series between the second common-mode inductor and the third filter, or installed between two sets of filter capacitors in the third filter.

[0020] The beneficial effects of the technical solution provided by this invention are:

[0021] This invention determines whether the AC power input is three-phase or single-phase based on the input sampling signal, thereby controlling the opening and closing of the relay switch to achieve compatible operation of single and three phases. Simultaneously, a unified filtering circuit is used for both single and three-phase operation, thus reducing the number of filtering and switching devices, further reducing the system size and cost. This invention uses only two relay switches, resulting in a simple circuit working principle, low control system cost, and achieving compatible operation of single and three phases simply by switching the relay switches. Furthermore, it simplifies the design of the input filter, using the same filtering equipment for both single and three-phase operation without requiring additional components, further reducing system cost and size.

[0022] It should be noted that existing three-phase converters operating in single-phase or three-phase mode use any one of phases A, B, or C as the live wire and the neutral wire (N) as the neutral wire. This requires a common-mode inductor with four coils, connected to phases A, B, C, and N respectively, to shield against common-mode interference between phases A / B / C and N during single-phase operation. This invention uses a three-winding common-mode inductor. During single-phase operation, the input interface selects one of phases B, C, or N to connect to the neutral wire. The EMC filter internally uses a relay connected to one of phases B or C, without adding additional common-mode inductor windings. Therefore, this invention's common-mode inductor has only three windings. Thus, this invention reduces the design complexity of the common-mode inductor and saves on its cost. Furthermore, the interleaved parallel operation method disclosed in this invention also reduces common-mode inductor losses to some extent. Attached Figure Description

[0023] The present invention will now be described in detail with reference to the embodiments and accompanying drawings, wherein:

[0024] Figure 1 is a schematic diagram of the topology of a vehicle charger with a three-phase power input;

[0025] Figure 2 shows the first fixed-terminal connection of the first switch K1 to filter input phase C L. C2 The second fixed terminal of the second switch K2 is connected to the rectifier phase B L. B4 A schematic diagram of the onboard charger topology;

[0026] Figure 3 shows the first fixed-terminal connection of the first switch K1 to the filter input phase C L. C2 The second fixed terminal of the second switch K2 is connected to the rectifier phase A L. A4 A schematic diagram of the onboard charger topology;

[0027] Figure 4 shows the first fixed-terminal connection of the first switch K1 to the filter input phase B L. B2 The second fixed terminal of the second switch K2 is connected to the rectifier C phase L. C4 A schematic diagram of the onboard charger topology;

[0028] Figure 5 shows the first fixed-terminal connection of the first switch K1 to the filter input phase B L. B2 The second fixed terminal of the second switch K2 is connected to the rectifier phase A L. A4 A schematic diagram of the onboard charger topology;

[0029] Figure 6 shows the first fixed-terminal connection of the first switch K1 to filter input phase A L. A2 The second fixed terminal of the second switch K2 is connected to the rectifier C phase L. C4 A schematic diagram of the onboard charger topology;

[0030] Figure 7 shows the first fixed-terminal connection of the first switch K1 to filter input phase A L. A2 The second fixed terminal of the second switch K2 is connected to the rectifier phase B L. B4 A schematic diagram of the onboard charger topology;

[0031] Figure 8 shows the topology of a voltage source rectifier;

[0032] Figure 9 shows the topology of a current source rectifier.

[0033] Figure 10 shows the topology of a multi-level PWM rectifier.

[0034] Figure 11 is a topology diagram of a three-phase Vienna rectifier;

[0035] Figure 12 shows the topology of a six-switch voltage-source rectifier that is compatible with both single-phase and three-phase circuits. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0037] This invention addresses the shortcomings of existing single-phase and three-phase compatible vehicle chargers, where the input filters for single-phase and three-phase power are separately configured. By determining whether the input is single-phase or three-phase based on the input sampling signal, the invention controls the switching on and off, achieving compatible operation of both single-phase and three-phase power. Figure 1 shows a schematic diagram of the topology of a vehicle charger with a three-phase power input, which includes an input power supply, an EMC filter, a boost inductor, and a three-phase rectifier connected in sequence.

[0038] As shown in Figures 2 to 7, this invention discloses a vehicle charger compatible with both single-phase and three-phase power supply, comprising an AC power input terminal, an EMC filter and a three-phase rectifier, a controller, a first switch K1 connected in series between the EMC filter and the AC power supply, and a second switch K2 connected in series between the EMC filter and the three-phase rectifier. The controller is used to control the operation of the first switch K1 and the second switch K2 when the AC power supply is three-phase, so that the three-phase power is delivered to the three-phase lines of the three-phase rectifier through the three-phase lines in the EMC filter for three-phase rectification; and to control the operation of the first switch K1 and the second switch K2 when the AC power supply is single-phase, so that the single-phase power is delivered to one phase line of the three-phase rectifier through one phase line in the EMC filter for single-phase rectification, or delivered to two phase lines of the three-phase rectifier for single-phase interleaved parallel rectification.

[0039] In a preferred embodiment, the first switch K1 includes a first fixed terminal, a first moving terminal, and a second moving terminal; the second switch K2 includes a second fixed terminal, a third moving terminal, and a fourth moving terminal. The first fixed terminal is connected to one phase of the EMC filter; the first moving terminal is connected to one phase of the AC power input terminal that corresponds to the phase connected to the first fixed terminal; the second moving terminal is connected to the neutral wire N of the AC power input terminal; the third and fourth moving terminals are respectively connected to two phases of the EMC filter that are not connected to the first fixed terminal; the second fixed terminal is connected to one phase of the three-phase rectifier that corresponds to the third and fourth moving terminals. The filter input phase A L... A2 Filtered input B phase L B2 and filter input C phase L C2Corresponding to phases A, B, and C in a three-phase power supply, if the first fixed terminal of the first switch K1 is connected to a certain phase (for example, to phase C), then the two moving terminals of the second switch K2 can only be connected to the other two phases respectively (the third and fourth moving terminals are connected to phase A or phase B respectively), and the second fixed terminal can only be connected to one of the other two phases (for example, to phase A or phase B).

[0040] In a preferred embodiment, when the AC power supply is three-phase, the first fixed terminal is connected to the first moving terminal, the first fixed terminal is disconnected from the second moving terminal, the second fixed terminal is connected to the third moving terminal when the phase connected to the second fixed terminal is the same as the phase connected to the third moving terminal, the second fixed terminal is disconnected from the fourth moving terminal, the second fixed terminal is connected to the fourth moving terminal when the phase connected to the second fixed terminal is the same as the phase connected to the fourth moving terminal, and the second fixed terminal is disconnected from the third moving terminal, to perform the three-phase rectification; in the AC power supply... When the power source is single-phase, the first fixed terminal is disconnected from the first moving terminal, the first fixed terminal is connected to the second moving terminal, the second fixed terminal is connected to the moving terminal of the third or fourth moving terminal that is connected to the same phase as the second fixed terminal, and the moving terminals that are connected to the second fixed terminal but are not connected to the same phase as the second fixed terminal, so as to perform the single-phase rectification; or the second fixed terminal is connected to the moving terminal of the third or fourth moving terminal that is connected to the same phase as the second fixed terminal, and the moving terminals that are connected to the same phase as the second fixed terminal are not connected to the second fixed terminal, so as to perform the single-phase interleaved parallel rectification.

[0041] In a preferred embodiment, the AC power input terminal includes phase A line L. A1 Phase B line L B1 C-phase line L C1 And the neutral line N, the EMC filter device includes a filter input A phase L A2 Filtered input B phase L B2 Filtered input C phase L C2 Filtered output A phase L A3 Filtered output B phase L B3 and filter output C phase L C3 The three-phase rectifier includes rectifier A phase L. A4 1. Rectifier B-phase L B4 rectifier C-phase L C4 .

[0042] Referring to the first embodiment shown in Figure 2, the first fixed terminal is connected to the filter input C phase L of the EMC filter device. C2 The first moving end is connected to the C phase line L in the AC power supply. C1 The A phase line L A1 Connect the filter input A phase L A2The B phase line L B1 Connect the filter input B phase L B2 The third moving terminal is connected to the filter output phase A L of the EMC filter device. A3 The fourth moving terminal is connected to the filter output phase B of the EMC filter device. B3 The second fixed terminal is connected to the rectifier phase B L in the three-phase rectifier. B4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output C-phase L C3 Connect the rectifier C phase L C4 It should be noted that in Figure 2, the second switch K2 is placed at position k. In other modified embodiments, the second switch K2 can be placed at any of the positions d, e, f, g, h, i, j, and k shown in the figure. When the power supply is single-phase, the single-phase line can be connected to phase line L of phase A. A1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N. Connecting to this point enables single-phase rectification or single-phase alternating parallel rectification. The ground wire of a single-phase power supply can also be connected to the C-phase wire L. C1 At this point, single-phase rectification or single-phase interleaved parallel rectification can be achieved. The ground wire of a single-phase power supply can also be connected to the B-phase line L. B1 At this point, single-phase rectification can be achieved; the phase wire of a single-phase power supply can be connected to phase B, L. B1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N, which enables single-phase rectification. The ground wire of a single-phase power supply can also be connected to the C-phase wire L. C1 At this point, single-phase rectification can be achieved.

[0043] Referring to the second embodiment shown in Figure 3, the connection method of the first switch K1 is the same as that of the first embodiment, while the connection method of the second switch K2 is different from that of the first embodiment. The first fixed terminal is connected to the filter input C phase L of the EMC filter device. C2 The first moving end is connected to the C phase line L in the AC power supply. C1 The A phase line L A1 Connect the filter input A phase L A2 The B phase line L B1 Connect the filter input B phase L B2 The third moving terminal is connected to the filter output phase A L of the EMC filter device. A3 The fourth moving terminal is connected to the filter output phase B of the EMC filter device. B3 The second fixed terminal is connected to the rectifier phase A L in the three-phase rectifier. A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 The filtered output C-phase LC3 Connect the rectifier C phase L C4 It should be noted that in Figure 3, the second switch K2 is placed at position k. In other modified embodiments, the second switch K2 can be placed at any of the positions d, e, f, g, h, i, j, and k shown in the figure. When the power supply is single-phase, the single-phase line can be connected to phase B line L. B1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N. Connecting to this point enables single-phase rectification or single-phase alternating parallel rectification. The ground wire of a single-phase power supply can also be connected to the C-phase wire L. C1 At this point, single-phase rectification or single-phase interleaved parallel rectification can be achieved. The ground wire of a single-phase power supply can also be connected to phase A line L. A1 At this point, single-phase rectification can be achieved; the phase line of a single-phase power supply can also be connected to phase line L of phase A. A1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N, which enables single-phase rectification. The ground wire of a single-phase power supply can also be connected to the C-phase wire L. C1 At this point, single-phase rectification can be achieved.

[0044] Referring to the third embodiment shown in Figure 4, the first fixed terminal is connected to the filter input phase B L of the EMC filter device. B2 The first moving end is connected to phase B, line L, of the AC power supply. B1 The A phase line L A1 Connect the filter input A phase L A2 The C-phase line L C1 Connect the filter input C phase L C2 The third moving terminal is connected to the filter output phase A L of the EMC filter device. A3 The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3 The second fixed terminal is connected to the rectifier C phase L in the three-phase rectifier. C4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 It should be noted that in Figure 4, the second switch K2 is placed at position k. In other modified embodiments, the second switch K2 can be placed at any of the positions d, e, f, g, h, i, j, and k shown in the figure. When the power supply is single-phase, the single-phase line can be connected to phase line L of phase A. A1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N. Connecting to this point enables single-phase rectification or single-phase alternating parallel rectification. The ground wire of a single-phase power supply can also be connected to the B-phase wire L. B1 At this point, single-phase rectification or single-phase interleaved parallel rectification can be achieved. The ground wire of a single-phase power supply can also be connected to the C-phase line L.C1 At this point, single-phase rectification can be achieved; the phase line of a single-phase power supply can also be connected to the C phase line L. C1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N, and connecting it at this point enables single-phase rectification. The ground wire of a single-phase power supply can also be connected to the B-phase wire L. B1 At this point, single-phase rectification can be achieved.

[0045] Referring to the fourth embodiment shown in Figure 5, the connection method of the first switch K1 is the same as that of the third embodiment, while the connection method of the second switch K2 is different from that of the third embodiment. The first fixed terminal is connected to the filter input phase B L of the EMC filter device. B2 The first moving end is connected to phase B, line L, of the AC power supply. B1 The A phase line L A1 Connect the filter input A phase L A2 The C-phase line L C1 Connect the filter input C phase L C2 The third moving terminal is connected to the filter output phase A L of the EMC filter device. A3 The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3 The second fixed terminal is connected to the rectifier phase A L in the three-phase rectifier. A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 The filtered output C-phase L C3 Connect the rectifier C phase L C4 It should be noted that in Figure 5, the second switch K2 is placed at position k. In other modified embodiments, the second switch K2 can be placed at any of the positions d, e, f, g, h, i, j, and k shown in the figure. When the power supply is single-phase, the single-phase line can be connected to phase C line L. C1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N. Connecting to this point enables single-phase rectification or single-phase alternating parallel rectification. The ground wire of a single-phase power supply can also be connected to the B-phase wire L. B1 At this point, single-phase rectification or single-phase interleaved parallel rectification can be achieved. The ground wire of a single-phase power supply can also be connected to phase A line L. A1 At this point, single-phase rectification can be achieved; the phase line of a single-phase power supply can also be connected to phase line L of phase A. A1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N, and connecting it at this point enables single-phase rectification. The ground wire of a single-phase power supply can also be connected to the B-phase wire L. B1 At this point, single-phase rectification can be achieved.

[0046] Referring to the fifth embodiment shown in Figure 6, the first fixed terminal is connected to the filter input phase A L of the EMC filter device. A2The first moving end is connected to phase A, line L in the AC power supply. A1 The B phase line L B1 Connect the filter input B phase L B2 The C-phase line L C1 Connect the filter input C phase L C2 The third moving terminal is connected to the filter output phase B of the EMC filter device. B3 The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3 The second fixed terminal is connected to the rectifier C phase L in the three-phase rectifier. C4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output B phase L B3 Connect the rectifier B phase L B4 In Figure 6, the second switch K2 is placed at position k. In other modified embodiments, the second switch K2 can be placed at any of the positions d, e, f, g, h, i, j, and k shown in the figure. When the power supply is single-phase, the single-phase line can be connected to phase B line L. B1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N. Connecting to this point enables single-phase rectification or single-phase alternating parallel rectification. The ground wire of a single-phase power supply can also be connected to phase A wire L. A1 At this point, single-phase rectification or single-phase interleaved parallel rectification can be achieved. The ground wire of a single-phase power supply can also be connected to the C-phase line L. C1 At this point, single-phase rectification can be achieved; the phase line of a single-phase power supply can also be connected to the C phase line L. C1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N, and connecting it at this point enables single-phase rectification. The ground wire of a single-phase power supply can also be connected to the A-phase wire L. A1 At this point, single-phase rectification can be achieved.

[0047] Referring to the sixth embodiment shown in Figure 7, the connection method of the first switch K1 is the same as in the fifth embodiment, while the connection method of the second switch K2 is different from that in the fifth embodiment. The first fixed terminal is connected to the filter input phase A L of the EMC filter device. A2 The first moving end is connected to phase A, line L in the AC power supply. A1 The B phase line L B1 Connect the filter input B phase L B2 The C-phase line L C1 Connect the filter input C phase L C2 The third moving terminal is connected to the filter output phase B of the EMC filter device. B3 The fourth moving terminal is connected to the filter output C phase L of the EMC filter device. C3The second fixed terminal is connected to the rectifier phase B L in the three-phase rectifier. B4 The filtered output A phase L A3 Connect the rectifier A phase L A4 The filtered output C-phase L C3 Connect the rectifier C phase L C4 In Figure 7, the second switch K2 is placed at position k. In other modified embodiments, the second switch K2 can be placed at any of the positions d, e, f, g, h, i, j, and k shown in the figure. When the power supply is single-phase, the single-phase line can be connected to phase C line L. C1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N. Connecting to this point enables single-phase rectification or single-phase alternating parallel rectification. The ground wire of a single-phase power supply can also be connected to phase A wire L. A1 At this point, single-phase rectification or single-phase interleaved parallel rectification can be achieved. The ground wire of a single-phase power supply can also be connected to the B-phase line L. B1 At this point, single-phase rectification can be achieved; the phase line of a single-phase power supply can also be connected to phase B line L. B1 At this point, the ground wire of a single-phase power supply can be connected to the neutral wire N, and connecting it at this point enables single-phase rectification. The ground wire of a single-phase power supply can also be connected to the A-phase wire L. A1 At this point, single-phase rectification can be achieved.

[0048] In a preferred embodiment, both the first switch K1 and the second switch K2 employ a single-pole double-throw relay; or the first switch K1 employs a combination of two single-pole single-throw relays, with one contact of the two single-pole single-throw relays connected in parallel serving as the first fixed terminal, and the unconnected contacts serving as the first moving terminal and the second moving terminal, respectively; or the second switch K2 employs a combination of two single-pole single-throw relays, with one contact of the two single-pole single-throw relays connected in parallel serving as the second fixed terminal, and the unconnected contacts serving as the third moving terminal and the fourth moving terminal, respectively.

[0049] In a preferred embodiment, the rectifier A phase L A4 An A-phase boost inductor L is provided between the three-phase rectifier and the transformer. A The rectifier B phase L B4 A B-phase boost inductor L is provided between the three-phase rectifier and the transformer. B The rectifier C phase L C4 A C-phase boost inductor L is provided between the three-phase rectifier and the transformer. C .

[0050] In a preferred embodiment, the EMC filtering device includes a first filter, a first common-mode inductor, a second filter, a second common-mode inductor, and a third filter connected in sequence.

[0051] In a preferred embodiment, the first common-mode inductor and the second common-mode inductor have the same structure, each including an integrated magnetic core and three windings wound on the integrated magnetic core, the three windings being connected in series one by one in the three phase lines.

[0052] It should be noted that existing three-phase converters operating in single-phase or three-phase mode use any one of phases A, B, or C as the live wire and the neutral wire (N) as the neutral wire. This requires a common-mode inductor with four coils, connected to phases A, B, C, and N respectively, to shield against common-mode interference between phases A / B / C and N during single-phase operation. This invention uses a three-winding common-mode inductor. During single-phase operation, the input interface selects one of phases B, C, or N to connect to the neutral wire. The EMC filter internally uses a relay connected to one of phases B or C, without adding additional common-mode inductor windings. Therefore, this invention's common-mode inductor has only three windings. Thus, this invention reduces the design complexity of the common-mode inductor and saves on its cost. Furthermore, the interleaved parallel operation method disclosed in this invention also reduces common-mode inductor losses to some extent.

[0053] In a preferred embodiment, the three-phase rectifier is one of a voltage source rectifier, a current source rectifier, a multi-level PWM rectifier, and a three-phase Vienna rectifier. Figure 8 shows a voltage source rectifier topology, Figure 9 shows a current source rectifier topology, Figure 10 shows a multi-level PWM rectifier topology, and Figure 11 shows a three-phase Vienna rectifier topology.

[0054] The following uses the topology diagram shown in Figure 2 as an example to illustrate the structure of a single-phase and three-phase compatible vehicle charger provided by the present invention. The AC power supply is a three-phase four-wire system, consisting of phase A, phase L, and phase L. A1 Phase B line L B1 C-phase line L C1 And neutral line N, phase line L A1 Phase B line L B1 Connect directly to the EMC filter device, on phase C line L C1 The first switch K1 is connected in series with the neutral line N, and the phase line L is connected in series with the neutral line. C1 The neutral line N is connected to the EMC filter via the first switch K1. In this example, the EMC filter consists of a first filter, a first common-mode inductor, a second filter, a second common-mode inductor, and a third filter connected in sequence. Figure 2 shows a capacitor filter; other filters such as LC filters and CLC filters can also be used, but this invention does not specifically limit their use. Phase A boost inductor L A With C-phase boost inductor L C The output phases A and C of the EMC filter are directly connected, and the boost inductor L in phase B is connected directly. BThe second switch K2 is connected to the filter output phase A and filter output phase B of the EMC filter, respectively. As a variation of the embodiments, the first switch K1 may also be integrated into the input terminal of the EMC filter, and the second switch K2 may be installed at various locations within the EMC filter: the second switch K2 is connected in series on the input side of the first filter (at point d in Figure 2), or in series between the first filter and the first common-mode inductor (at point e in Figure 2), or in series between the first common-mode inductor and the second filter (at point f in Figure 2), or installed between two sets of filter capacitors within the second filter (at point g in Figure 2), or in series between the second filter and the second common-mode inductor (at point h in Figure 2), or in series between the second common-mode inductor and the third filter (at point i in Figure 2), or installed between two sets of filter capacitors within the third filter (at point j in Figure 2). The second filter contains C... Y1 C Y2 and C Y3 For the first group of filter capacitors, C X4 C X5 and C X6 and C Y4 The second set of filter capacitors, along with the first set which significantly reduces common-mode signal interference on the AC side of the power supply by introducing the common-mode signal to ground, serves to filter out differential-mode signals generated by the inductor and converter, thus smoothing the input current waveform. The third filter contains capacitor C. Y5 C Y6 and C Y7 For the third group of filter capacitors, C X7 C X8 and C X9 and C Y8 The fourth set of filter capacitors, following the third set which significantly reduced common-mode signal interference on the AC side of the power supply by introducing the common-mode signal to ground, primarily filters out differential-mode signals generated by the inductor and converter, thus smoothing the input current waveform.

[0055] The three-phase rectifier is directly connected to the boost inductor. The three-phase rectifier can be any unidirectional / bidirectional three-phase rectifier topology, such as the voltage source rectifier shown in Figure 8, the current source rectifier shown in Figure 9, the multi-level PWM rectifier shown in Figure 10, or the three-phase Vienna rectifier shown in Figure 11.

[0056] The working principle of a single-phase and three-phase compatible on-board charger provided by this invention will be described in detail below, taking the single-phase and three-phase compatible six-switch voltage rectifier topology diagram shown in Figure 12 as an example:

[0057] When the AC power supply is three-phase, the input voltage sampling circuit identifies it as a three-phase input. The controller then controls the first switch K1 to operate (if it's a single-pole double-throw switch, the first moving terminal of switch K1 closes; if it's two single-pole single-throw switches, the first moving terminal closes) and connects to phase C line L. C1 Connection; control the action of the second switch K2 (if it is a single-pole double-throw switch, it will close the fourth moving terminal of the second switch K2; if it is two single-pole single-throw switches, it will close the fourth moving terminal) and the filter output B phase L. B3 Connection; After the three-phase AC power supply is input to the EMC filter, it is rectified by a three-phase rectifier to generate DC voltage V. bus .

[0058] When the input is single-phase electricity, and the single-phase line is connected to phase line A L. A1 At this location, if the ground wire of a single-phase power supply is selected as the neutral wire N, the controller will activate the first switch K1 (if it is a single-pole double-throw switch, it will close the second moving terminal of the first switch K1; if it is two single-pole single-throw switches, it will close the second moving terminal) to connect it to the neutral wire N; the second switch K2 will activate (if it is a single-pole double-throw switch, it will close the third moving terminal of the second switch K2; if it is two single-pole single-throw switches, it will close the third moving terminal) to rectify phase B L. B4 Phase L of the filtered output A A3 Connection; AC power is rectified through phase A L. A4 and rectifier B phase L B4 In the input rectifier circuit, a two-phase interleaved input is implemented. The neutral line N is input into the three-phase six-switch circuit through the first switch K1, forming an interleaved parallel totem-pole PFC rectifier to generate a DC voltage V. bus Alternatively, for single-phase electricity, the ground wire should be phase C (L). C1 At this point, the controller controls the first switch K1 to operate (if it is a single-pole double-throw switch, it closes the first moving end of the first switch K1; if it is two single-pole single-throw switches, it closes the first moving end) and connects to phase line L of C. C1 Connection; Second switch K2 operation (if it is a single-pole double-throw switch, it will close the third moving terminal of the second switch K2; if it is two single-pole single-throw switches, it will close the third moving terminal) Rectifies phase B line L B4 With the filtered output A phase line L A3 Connection; AC power is rectified through phase A line L. A4 and rectifier B phase line L B4 Two-phase interleaved input is implemented in the input rectifier circuit, with phase C line L C1 The circuit input through the first switch K1 into the three-phase six-switch circuit forms an interleaved parallel totem-pole PFC rectifier, generating a DC voltage V. bus .

[0059] When the input is single-phase electricity, and the single-phase line is connected to phase line A L. A1At this location, the ground wire for single-phase electricity is selected as the neutral wire N. It can also control the operation of the first switch K1 (if it's a single-pole double-throw switch, it closes the second moving terminal; if it's two single-pole single-throw switches, it closes the second moving terminal) to connect to the neutral wire N. The operation of the second switch K2 (if it's a single-pole double-throw switch, it closes the fourth moving terminal; if it's two single-pole single-throw switches, it closes the fourth moving terminal) connects the AC power supply to phase A L after rectification. A4 In the input rectifier circuit, the neutral wire N is input into the three-phase six-switch circuit through the first switch K1 for single-phase rectification. Alternatively, the ground wire for single-phase power can be selected from phase C, L. C1 At this location, the operation of the first switch K1 can also be controlled (if it is a single-pole double-throw switch, the first moving end of the first switch K1 will be closed; if it is two single-pole single-throw switches, the first moving end will be closed) and the C phase line L. C1 Connection; the second switch K2 operates (if it is a single-pole double-throw switch, it closes the fourth moving terminal of the second switch K2; if it is two single-pole single-throw switches, it closes the fourth moving terminal), and the AC power passes through the rectified phase A L. A4 In the input rectifier circuit, phase C line L C1 The circuit is input into the three-phase six-switch circuit through the first switch K1 for single-phase rectification.

[0060] It should be noted that in the example of Figure 12, when the input is single-phase electricity, if the phase line of the single-phase electricity is connected to phase line L of phase B... B1 For single-phase power, the ground wire can be selected as the neutral wire (N). This controls the closing of the second moving terminal of the first switch K1 and the fourth moving terminal of the second switch K2, allowing the three-phase rectifier to perform single-phase rectification. Alternatively, the ground wire for single-phase power can be selected as the C phase wire (L). C1 At this point, the first moving end of the first switch K2 can be closed, and the fourth moving end of the second switch K2 can be closed, so that the three-phase rectifier can perform single-phase rectification.

[0061] Figures 2, 4, and 6 show similar control characteristics in the embodiments. When the AC power supply is three-phase, the first moving terminal of the first switch K1 is connected to the first fixed terminal, and the second moving terminal is disconnected from the first fixed terminal; the fourth moving terminal of the second switch K2 is connected to the second fixed terminal, and the third moving terminal is disconnected from the second fixed terminal, allowing the three-phase rectifier to perform three-phase rectification. When the AC power supply is single-phase, and the single-phase line is connected to phase line L in the three embodiments, the control characteristics are similar. A1 Location, Phase A line L A1 Location and B phase line L B1When the ground wire of a single-phase power supply is connected to the neutral wire N, the second moving terminal of the first switch K1 is connected to the first fixed terminal, and the first moving terminal is disconnected from the first fixed terminal; the third moving terminal of the second switch K2 is connected to the second fixed terminal, and the fourth moving terminal is disconnected from the second fixed terminal, and the three-phase rectifier performs single-phase interleaved parallel rectification; or the fourth moving terminal of the second switch K2 is connected to the second fixed terminal, and the third moving terminal is disconnected from the second fixed terminal, and the three-phase rectifier performs single-phase rectification. When the AC power supply is a single-phase power supply, and the phase wires of the single-phase power supply are respectively connected to phase wire L of phase A in the three embodiments. A1 Location, Phase A line L A1 Location and B phase line L B1 At this point, the ground wires of the single-phase power are connected to the C-phase line L. C1 Location, B phase line L B1 Location and phase line L of A A1 When the first switch K1 is in operation, the first moving terminal is connected to the first fixed terminal, and the second moving terminal is disconnected from the first fixed terminal; the third moving terminal of the second switch K2 is connected to the second fixed terminal, and the fourth moving terminal is disconnected from the second fixed terminal, and the three-phase rectifier performs single-phase interleaved parallel rectification; or the fourth moving terminal of the second switch K2 is connected to the second fixed terminal, and the third moving terminal is disconnected from the second fixed terminal, and the three-phase rectifier performs single-phase rectification. If the AC power supply is a single-phase power supply, and the single-phase power line is connected to phase B line L in the three embodiments respectively. B1 Location, C phase line L C1 Location and C phase line L C1 When the ground wire of a single-phase power supply is connected to the neutral wire N, the second moving terminal of the first switch K2 can be closed, and the connection between the first moving terminal and the first fixed terminal can be broken. Conversely, the fourth moving terminal of the second switch K2 can be connected to the second fixed terminal, and the third moving terminal can be disconnected from the second fixed terminal, allowing the three-phase rectifier to perform single-phase rectification. When the AC power supply is single-phase, and the single-phase power supply's phase wire is connected to phase B L in the three embodiments... B1 Location, C phase line L C1 Location and C phase line L C1 At this point, the ground wires of the single-phase power are connected to the C-phase line L. C1 Location, B phase line L B1 Location and phase line L of A A1 When in operation, the first moving end of the first switch K1 can be closed, and the second moving end can be disconnected from the first fixed end. The fourth moving end of the second switch K2 can be connected to the second fixed end, and the third moving end can be disconnected from the second fixed end, so that the three-phase rectifier can perform single-phase rectification.

[0062] Figures 3, 5, and 7 show similar control characteristics in the embodiments. When the AC power supply is three-phase, the first moving terminal of the first switch K1 is connected to the first fixed terminal, and the second moving terminal is disconnected from the first fixed terminal; the third moving terminal of the second switch K2 is connected to the second fixed terminal, and the fourth moving terminal is disconnected from the second fixed terminal, allowing the three-phase rectifier to perform three-phase rectification. When the AC power supply is single-phase, and the single-phase line is connected to phase B line L in the three embodiments, the control characteristics are similar. B1 Location, C phase line L C1 Location and C phase line L C1 When the ground wire of a single-phase power supply is connected to the neutral wire N, the second moving terminal of the first switch K1 is connected to the first fixed terminal, and the first moving terminal is disconnected from the first fixed terminal; the fourth moving terminal of the second switch K2 is connected to the second fixed terminal, and the third moving terminal is disconnected from the second fixed terminal, and the three-phase rectifier performs single-phase interleaved parallel rectification; or the third moving terminal of the second switch K2 is connected to the second fixed terminal, and the fourth moving terminal is disconnected from the second fixed terminal, and the three-phase rectifier performs single-phase rectification. When the AC power supply is a single-phase power supply, and the phase wires of the single-phase power supply are respectively connected to phase B line L in the three embodiments. B1 Location, C phase line L C1 Location and C phase line L C1 At this point, the ground wires of the single-phase power are connected to the C-phase line L. C1 Location, B phase line L B1 Location and phase line L of A A1 When the first moving terminal of the first switch K1 is connected to the first fixed terminal, and the second moving terminal is disconnected from the first fixed terminal; when the second switch K2 is connected to the second fixed terminal, and the third moving terminal is disconnected from the second fixed terminal, the three-phase rectifier performs single-phase interleaved parallel rectification; or when the third moving terminal of the second switch K2 is connected to the second fixed terminal, and the fourth moving terminal is disconnected from the second fixed terminal, the three-phase rectifier performs single-phase rectification. If the AC power supply is a single-phase power supply, and the single-phase power line is connected to phase line L in each of the three embodiments... A1 Location, Phase A line L A1 Location and B phase line L B1 When the ground wire of a single-phase power supply is connected to the neutral wire N, the second moving terminal of the first switch K1 can be closed, and the connection between the first moving terminal and the first fixed terminal can be broken. Conversely, the third moving terminal of the second switch K2 can be connected to the second fixed terminal, and the fourth moving terminal can be broken. The three-phase rectifier then performs single-phase rectification. When the AC power supply is single-phase, and the single-phase power line is connected to phase B L in the three embodiments... B1 Location, C phase line L C1 Location and C phase line L C1 At this point, the ground wires of the single-phase power are connected to the C-phase line L. C1 Location, B phase line L B1 Location and phase line L of A A1When in operation, the first moving end of the first switch K1 can be closed, and the second moving end can be disconnected from the first fixed end; the third moving end of the second switch K2 can be connected to the second fixed end, and the fourth moving end can be disconnected from the second fixed end, so that the three-phase rectifier can perform single-phase rectification.

[0063] The above embodiments are merely illustrative and not intended to be limiting. Any equivalent modifications or alterations made without departing from the spirit and scope of this application should be included within the scope of the claims of this application.

Claims

1. A single and three phase compatible on-board charger comprising an AC supply input, EMC filtering means and a three phase rectifier characterised in that: The controller, a first switch K1 connected in series between the EMC filter and the AC power supply, and a second switch K2 connected in series between the EMC filter and the three-phase rectifier; The controller is configured to control the first switch K1 and the second switch K2 to operate when the AC power supply is a three-phase power, so that the three-phase power is transmitted through the three-phase lines in the EMC filter to the three-phase lines in the three-phase rectifier for three-phase rectification. When the AC power supply is a single-phase power, the controller controls the first switch K1 and the second switch K2 to operate, so that the single-phase power is transmitted through one phase line in the EMC filter to one phase line in the three-phase rectifier for single-phase rectification, or to two phase lines in the three-phase rectifier for single-phase interleaved parallel rectification.

2. The single- and three-phase compatible on-board charger of claim 1, wherein: The first switch K1 includes a first fixed terminal, a first movable terminal, and a second movable terminal, and the second switch K2 includes a second fixed terminal, a third movable terminal, and a fourth movable terminal. The first fixed terminal is connected to one phase line in the EMC filter, the first movable terminal is connected to one phase line in the AC power supply input end consistent with the phase connected to the first fixed terminal, and the second movable terminal is connected to the neutral line N in the AC power supply input end. The third movable terminal and the fourth movable terminal are respectively connected to two phase lines in the EMC filter that are not connected to the first fixed terminal, and the second fixed terminal is connected to one of the two phase lines in the three-phase rectifier corresponding to the third movable terminal and the fourth movable terminal.

3. The single- and three-phase compatible on-board charger of claim 2, wherein: When the AC power supply is a three-phase power, the first fixed terminal is connected to the first movable terminal, the first fixed terminal is disconnected from the second movable terminal, the phase connected to the second fixed terminal is the same as the phase connected to the third movable terminal, the second fixed terminal is connected to the third movable terminal, the phase connected to the second fixed terminal is different from the phase connected to the fourth movable terminal, the second fixed terminal is disconnected from the fourth movable terminal, and the second fixed terminal is disconnected from the third movable terminal, so as to perform the three-phase rectification. When the AC power supply is a single-phase power, the first fixed terminal is disconnected from the first movable terminal, the first fixed terminal is connected to the second movable terminal, the second fixed terminal is connected to the third movable terminal and the fourth movable terminal that are the same as the phase connected to the second fixed terminal, and the second fixed terminal is disconnected from the movable terminal that is different from the phase connected to the second fixed terminal, so as to perform the single-phase rectification, or the second fixed terminal is connected to the third movable terminal and the fourth movable terminal that are different from the phase connected to the second fixed terminal, and the second fixed terminal is disconnected from the movable terminal that is the same as the phase connected to the second fixed terminal, so as to perform the single-phase interleaved parallel rectification.

4. The single- and three-phase compatible on-board charger of claim 2, wherein: The AC power input comprises an A-phase line L A1 , a B-phase line L B1 , a C-phase line L C1 and a neutral line N, the EMC filter arrangement comprises a filter input A-phase L A2 , a filter input B-phase L B2 , a filter input C-phase L C2 , a filter output A-phase L A3 , a filter output B-phase L B3 and a filter output C-phase L C3 , the three-phase rectifier comprises a rectification A-phase L A4 , a rectification B-phase L B4 , a rectification C-phase L C4 .

5. The single- and three-phase compatible on-board charger of claim 4, wherein: The first fixed end connects a filter input C phase L in the EMC filter device C2 The first moving end connects a C phase line L in the alternating current power supply C1 The A phase line L A1 connects the filter input A phase L A2 The B phase line L B1 connects the filter input B phase L B2 ; The third moving terminal is connected with a filter output A phase L in the EMC filter device A3 The fourth moving terminal is connected with a filter output B phase L in the EMC filter device B3 The second fixed terminal is connected with a rectification B phase L in the three-phase rectifier B4 The filter output A phase L A3 is connected with the rectification A phase L A4 The filter output C phase L C3 is connected with the rectification C phase L C4 ; or the third moving terminal is connected with a filter output A phase L in the EMC filter device A3 The fourth moving terminal is connected with a filter output B phase L in the EMC filter device B3 The second fixed terminal is connected with a rectification A phase L in the three-phase rectifier A4 The filter output B phase L B3 is connected with the rectification B phase L B4 The filter output C phase L C3 is connected with the rectification C phase L C4 .

6. The single-phase and three-phase compatible vehicle charger according to claim 4, wherein: The first fixed end connects the filter input B phase L in the EMC filter device B2 The first moving end connects the B phase line L in the alternating current power supply B1 The A phase line L A1 connects the filter input A phase L A2 The C phase line L C1 connects the filter input C phase L C2 ; the third movable terminal is connected to a filter output A-phase L in the EMC filter device A3 the fourth movable terminal is connected to a filter output C-phase L in the EMC filter device C3 the second fixed terminal is connected to a rectification C-phase L in the three-phase rectifier C4 the filter output A-phase L A3 is connected to the rectification A-phase L A4 the filter output B-phase L B3 is connected to the rectification B-phase L B4 ; or the third movable terminal is connected to a filter output A-phase L in the EMC filter device A3 the fourth movable terminal is connected to a filter output C-phase L in the EMC filter device C3 the second fixed terminal is connected to a rectification A-phase L in the three-phase rectifier A4 the filter output B-phase L B3 is connected to the rectification B-phase L B4 the filter output C-phase L C3 is connected to the rectification C-phase L C4 .

7. The on-board charger compatible with both single-phase and three-phase as described in claim 2, characterized in that: The first switch K1 and the second switch K2 are both single-pole double-throw relays; or the first switch K1 is composed of two single-pole single-throw relays, one contact of the two single-pole single-throw relays is connected in parallel to serve as the first fixed terminal, and the other contact serves as the first movable terminal and the second movable terminal; or the second switch K2 is composed of two single-pole single-throw relays, one contact of the two single-pole single-throw relays is connected in parallel to serve as the second fixed terminal, and the other contact serves as the third movable terminal and the fourth movable terminal.

8. The single- and three-phase compatible on-board charger of claim 1, wherein: The EMC filter device comprises a first filter, a first common-mode inductor, a second filter, a second common-mode inductor and a third filter connected in sequence.

9. The single- and three-phase compatible on-board charger of claim 8, wherein: The first common-mode inductor and the second common-mode inductor have the same structure, both comprising an integrated magnetic core and three windings wound on the integrated magnetic core, and the three windings are connected in series in the three-phase line one by one.

10. The single- and three-phase compatible on-board charger of claim 8, wherein: The first switch K1 is integrated at the input end of the EMC filter device, and the second switch K2 is connected in series at the input side of the first filter, or between the first filter and the first common-mode inductor, or between the first common-mode inductor and the second filter, or between two sets of filter capacitors in the second filter, or between the second filter and the second common-mode inductor, or between the second common-mode inductor and the third filter, or between two sets of filter capacitors in the third filter.

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