Charging systems, energy storage systems and vehicles

Abstract

The present application discloses a charging system, an energy storage system and a vehicle, and belongs to the field of charging. The charging system includes: a non-isolated charger, the non-isolated charger is connected between the power grid and the energy storage device, and at least one capacitor module is arranged between the phase line and the neutral line of the non-isolated charger; an active leakage current suppression circuit, the active leakage current suppression circuit includes a power supply device, and the power supply device is used to provide power excitation to the active leakage current suppression circuit so that the active leakage current suppression circuit generates a reverse leakage current with an amplitude difference of no more than a target range and opposite phase from the leakage current in the charging system. The charging system of the present application can effectively realize leakage current suppression, and has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

Description

Technical Field

[0001] The present application belongs to the field of charging systems, and in particular, relates to a charging system, an energy storage system and a vehicle. Background Art

[0002] For non-isolated electric vehicle on-board chargers (OBCs), since the AC side is directly connected to the DC side, the common-mode voltage on the AC input grid side can be transmitted to the safety Y capacitor and distributed Y capacitor on the DC side, thereby generating a large power frequency leakage current. If the leakage current value exceeds the detection threshold, the external charging device will interrupt the charging process, thereby affecting the user experience. In the related technology, there is a lack of effective leakage current suppression methods, and the leakage current suppression cost is high. Summary of the invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a charging system, an energy storage system and a vehicle, which can effectively suppress leakage current, have a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

[0004] In a first aspect, the present application provides a charging system, the system comprising:

[0005] A non-isolated charger, wherein the non-isolated charger is connected between the power grid and the energy storage device, and at least one capacitor module is provided between the phase line and the neutral line of the non-isolated charger;

[0006] An active leakage current suppression circuit, the active leakage current suppression circuit comprising a power supply device, the active leakage current suppression circuit is respectively connected to the ground line of the power grid and the neutral point of the first target capacitor module in the at least one capacitor module; the power supply device is used to provide power excitation to the active leakage current suppression circuit so that the active leakage current suppression circuit generates a reverse leakage current whose amplitude difference from the leakage current in the charging system does not exceed a target range and has an opposite phase.

[0007] According to the charging system of the present application, an active leakage current suppression circuit is set up that is independent of the control logic of the original circuit to generate a reverse leakage current whose amplitude difference from the leakage current in the circuit of the charging system does not exceed the target range and whose phase is opposite, and is injected into the circuit of the charging system, so that the net leakage current on the ground wire approaches 0, thereby effectively realizing leakage current suppression, and the system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

[0008] According to one embodiment of the present application, the active leakage current suppression circuit further includes:

[0009] A first Y capacitor;

[0010] A first transformer, wherein the primary side of the first transformer is connected to the power supply device, the first end of the secondary side of the first transformer is connected to the ground wire via the first Y capacitor, and the second end of the secondary side of the first transformer is connected to the neutral point of the first target capacitor module.

[0011] According to one embodiment of the present application, the active leakage current suppression circuit further includes: a second transformer,

[0012] The primary side of the second transformer is used to access the power grid, and the second transformer and the first transformer are connected in series or in parallel, wherein:

[0013] In the case where the first transformer is connected in series with the second transformer, the third end of the secondary side of the second transformer is connected to the neutral point of the first target capacitor module, and the fourth end of the secondary side of the second transformer is connected to the second end of the secondary side of the first transformer;

[0014] When the first transformer is connected in parallel with the second transformer, the third end of the secondary side of the second transformer is connected to the neutral point of the second target capacitor module in the at least one capacitor module, and the fourth end of the secondary side of the second transformer is connected to the ground wire via a second Y capacitor.

[0015] According to one embodiment of the present application, the power supply device includes: an active leakage current suppression excitation circuit, and the active leakage current suppression excitation circuit is connected to the primary side of the first transformer.

[0016] According to one embodiment of the present application, the power supply device includes:

[0017] A voltage source module, wherein an output end of the voltage source module is connected to a primary side of the first transformer;

[0018] A first sampling module, wherein the first sampling module is connected to the voltage source module and is used to collect a leakage current of the ground line and control the voltage source module based on the leakage current.

[0019] According to one embodiment of the present application, the voltage source module includes:

[0020] A first battery, a first high-frequency inverter, a first low-pass filter and a first filter, wherein the output end of the first filter is connected to the primary side of the first transformer; and the first sampling module is connected to the first high-frequency inverter.

[0021] According to one embodiment of the present application, the voltage source module includes:

[0022] A rectifier circuit, a first DC / DC converter, a second high-frequency inverter, a second low-pass filter and a second filter, wherein the output end of the second filter is connected to the primary side of the first transformer, and the rectifier circuit is connected to the power grid; the first sampling module is connected to the second high-frequency inverter.

[0023] According to one embodiment of the present application, the voltage source module includes:

[0024] A second DC / DC converter, a third high-frequency inverter, a third low-pass filter and a third filter, wherein the output end of the third filter is connected to the primary side of the first transformer, and the input end of the second DC / DC converter is connected to the two ends of the energy storage device; the first sampling module is connected to the third high-frequency inverter.

[0025] According to one embodiment of the present application, the power supply device includes:

[0026] A third DC / DC converter, a fourth high-frequency inverter, a fourth low-pass filter and a fourth filter, wherein a first output end of the fourth filter is connected to the ground line via a first Y capacitor included in the active leakage current suppression circuit, a second output end of the fourth filter is connected to a neutral point of the first target capacitor module, and an input end of the third DC / DC converter is connected to two ends of the energy storage device;

[0027] A second sampling module connected to the fourth high-frequency inverter, the second sampling module is used to collect a leakage current of the ground line and control the fourth high-frequency inverter based on the leakage current.

[0028] According to one embodiment of the present application, the non-isolated charger includes: a first sub-filter, an H-bridge circuit, and a second sub-filter, wherein:

[0029] The input end of the first sub-filter is used to access the power grid; the output end of the second sub-filter is connected to the energy storage device;

[0030] The capacitor module is arranged before the input end of the first sub-filter, or between the first sub-filter and the H-bridge circuit, or after the output end of the H-bridge circuit, or after the second sub-filter.

[0031] According to one embodiment of the present application, it also includes:

[0032] A switch module, wherein the switch module is arranged between the phase line and the neutral line of the power grid and the non-isolated charger;

[0033] A third switch is provided between the active leakage current suppression circuit and the non-isolated charger.

[0034] In a second aspect, the present application provides an energy storage system, the energy storage system comprising:

[0035] Energy storage devices;

[0036] As described in the first aspect, the charging system is connected to the energy storage device.

[0037] In a third aspect, the present application provides a vehicle, the vehicle comprising:

[0038] An energy storage system as described in the second aspect.

[0039] According to the vehicle of the present application, an active leakage current suppression circuit is set up with a control logic independent of the original circuit to generate a reverse leakage current with an amplitude that does not exceed a target range and has an opposite phase to the leakage current in the circuit of the charging system, and inject it into the circuit of the charging system, so that the net leakage current on the ground wire approaches 0, thereby effectively achieving leakage current suppression, and the structure is simple, the control complexity is low, the design cost is low, and it has high reliability and a wide range of applicable scenarios.

[0040] The above one or more technical solutions in the embodiments of the present application have at least one of the following technical effects:

[0041] An active leakage current suppression circuit independent of the control logic of the original circuit is set up to generate a reverse leakage current with an amplitude not exceeding a target range and an opposite phase to the leakage current in the circuit of the charging system, and inject it into the circuit of the charging system, so that the net leakage current on the ground wire approaches 0, thereby effectively achieving leakage current suppression. The circuit has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

[0042] Furthermore, the reverse leakage current injection is directly implemented through the first Y capacitor without the aid of a transformer, thereby further reducing system components and reducing the cost of the leakage current suppression circuit.

[0043] Furthermore, by setting up multiple switches, compatibility with single-phase input and three-phase input can be achieved, further improving the applicable scenarios and scope of the charging system.

[0044] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0046] Figure 1 It is one of the structural schematic diagrams of the charging system provided in the embodiment of the present application;

[0047] Figure 2 This is the second structural diagram of the charging system provided in the embodiment of the present application;

[0048] Figure 3 This is the third structural diagram of the charging system provided in the embodiment of the present application;

[0049] Figure 4 This is the fourth structural diagram of the charging system provided in the embodiment of the present application;

[0050] Figure 5 This is the fifth structural diagram of the charging system provided in the embodiment of the present application;

[0051] Figure 6 This is the sixth structural diagram of the charging system provided in the embodiment of the present application;

[0052] Figure 7 This is the seventh structural diagram of the charging system provided in the embodiment of the present application;

[0053] Figure 8 This is the eighth structural diagram of the charging system provided in the embodiment of the present application;

[0054] Fig. 9 This is the ninth structural diagram of the charging system provided in the embodiment of the present application;

[0055] Fig.10 This is the tenth structural diagram of the charging system provided in the embodiment of the present application. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0057] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0058] The charging system and vehicle provided in the embodiments of the present application are described in detail below through specific embodiments and their application scenarios in conjunction with the accompanying drawings.

[0059] like Figure 1 As shown, the charging system includes: a non-isolated charger 20 and an active leakage current suppression circuit 40 .

[0060] The non-isolated charger 20 is connected between the power grid 10 and the energy storage device 30 to achieve conversion from AC to DC.

[0061] The power grid 10 may include a single-phase input power grid or a three-phase input power grid.

[0062] The energy storage device 30 may include various types of energy storage batteries and the like.

[0063] In some embodiments, a switch module 50 may be provided in each phase line and neutral line of the three-phase input power grid to control the on and off of the corresponding branch, thereby realizing switching between the single-phase charging mode and the three-phase charging mode.

[0064] It is understandable that the charging system may include a charging pile end and a vehicle end, wherein the charging pile end is provided with power input by an AC source of the power grid 10, and the vehicle end includes a non-isolated charger 20, which converts AC into DC to charge the energy storage device 30.

[0065] During vehicle charging, the common-mode voltage contained in the AC input of the single-phase grid 10 will charge and discharge the safety Y capacitor in the circuit and the distributed Y capacitor of the high-voltage device to the vehicle body ground, thereby forming a common-mode current, namely the leakage current Ileak; this leakage current returns to the input side of the grid 10 through the ground wire, causing electromagnetic interference problems; if it exceeds the leakage current design threshold of the external charging device, charging will be terminated, reducing the user's charging experience; if the ground wire fails, it may even threaten personal safety.

[0066] like Figure 2 As shown, the non-isolated charger 20 includes at least one capacitor module.

[0067] The capacitor module is arranged between the phase line and the neutral line.

[0068] In some embodiments, the capacitor module may include a first sub-capacitor and a second sub-capacitor connected in series.

[0069] The first sub-capacitor and the second sub-capacitor are connected in series and arranged between the L line and the N line of the power grid 10. Figure 5 C1 and C2 in Figure 5 C3 and C4 in Figure 5 As shown in C5 and C6 in FIG.

[0070] The neutral point of the capacitor module is the potential midpoint between the first sub-capacitor and the second sub-capacitor.

[0071] The number of the capacitor modules may be one or more.

[0072] like Figure 3 As shown, in some embodiments, the non-isolated charger 20 may include: a first sub-filter 21 , an H-bridge circuit 22 , and a second sub-filter 23 connected in series.

[0073] In this embodiment, an input end of the first sub-filter 21 is connected to a phase line of the power grid 10 for receiving the alternating current of the power grid 10 .

[0074] In some embodiments, the first sub-filter 21 and the second sub-filter 23 may include a π-type filter or other types of EMI filters, etc., which is not limited in the present application.

[0075] An input end of the first sub-filter 21 is used to access the alternating current of the power grid 10 .

[0076] An output end of the second sub-filter 23 is connected to the energy storage device 30 .

[0077] In some embodiments, the capacitor module can be arranged before the input end of the first sub-filter 21, can be arranged between the output end of the first sub-filter 21 and the input end of the H-bridge circuit 22, can be arranged after the input end of the H-bridge circuit 22, or can also be arranged after the output end of the second sub-filter 23, and the present application does not limit this.

[0078] The active leakage current suppression circuit 40 includes: a power supply device.

[0079] The power supply device is used to provide power excitation to the active leakage current suppression circuit 40 so that the active leakage current suppression circuit 40 generates a reverse leakage current whose amplitude does not differ from the leakage current in the circuit of the charging system by more than the target range and whose phase is opposite, thereby injecting the reverse leakage current into the charging system.

[0080] The target range is a smaller range that can be customized by the user.

[0081] The difference can be a difference or a ratio, etc.

[0082] It can be understood that, when the difference does not exceed the target range, it can be approximately considered that the magnitude of the reverse leakage current is the same or substantially the same as the magnitude of the leakage current in the circuit of the charging system.

[0083] In some embodiments, the active leakage current suppression circuit 40 is respectively connected to the ground line of the power grid 10 and the neutral point of a first target capacitor module in the at least one capacitor module.

[0084] The first target capacitor module may be any one of the at least one capacitor module.

[0085] The power supply device is used to provide power excitation to the active leakage current suppression circuit 40 so that the active leakage current suppression circuit 40 generates a reverse leakage current whose amplitude difference from the leakage current in the circuit of the charging system does not exceed the target range and has an opposite phase, and the reverse leakage current is injected into the circuit of the charging system through the first target capacitor module, so that the net leakage current on the ground line approaches 0, thereby achieving leakage current suppression.

[0086] It should be noted that based on different types of power supply devices, the active leakage current suppression circuit 40 can be set to different structures accordingly. For example, the active leakage current suppression excitation circuit can be connected in series with the first Y capacitor CY1 through a transformer to achieve active leakage current suppression; or, the power supply device and the first Y capacitor CY1 can be directly connected in series to achieve active leakage current suppression, which is not limited in this application.

[0087] The specific configuration of the active leakage current suppression circuit 40 will be described in the following embodiments, and will not be elaborated in detail in this application.

[0088] During the research and development process, the inventors discovered that in the related technologies, there are methods of setting up a DC blocking capacitor to suppress leakage current, or adjusting the PFC duty cycle according to the AC input, DC bus voltage and ground leakage current sampling values ​​to reduce the low-frequency leakage current, or matching the Y capacitor parameters of the whole vehicle to set up a passive industrial frequency transformer leakage current suppression circuit to reduce the low-frequency leakage current. The above methods have problems such as low flexibility, great design difficulty, high circuit complexity, high design cost and poor suppression effect.

[0089] In the present application, the active leakage current suppression method can eliminate the influence of the Y capacitor value drift, so that it can match different vehicle designs and adapt to various working environment conditions, with high flexibility; the requirements for new circuit elements are low, and the Y capacitor required by the suppression circuit is low, which can meet the application scenarios of on-board chargers with high voltage resistance requirements; in addition, the control logic of the active leakage current suppression circuit 40 is independent of the control logic of the original circuit, with low control complexity, and will not affect the original electrical performance of the circuit.

[0090] According to the charging system provided in the embodiment of the present application, an active leakage current suppression circuit 40 independent of the control logic of the original circuit is set to generate a reverse leakage current with an amplitude difference not exceeding a target range and an opposite phase from the leakage current in the circuit of the charging system, and inject it into the circuit of the charging system, so that the net leakage current on the ground line approaches 0, thereby effectively achieving leakage current suppression, and the system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

[0091] like Figure 2 As shown, in some embodiments, the active leakage current suppression circuit 40 may include: a first Y capacitor CY1 and a first transformer T1.

[0092] In this embodiment, the power supply means is a means for providing excitation.

[0093] The primary side of the first transformer T1 is connected to the power supply device, and the first end of the secondary side of the first transformer T1 is connected to the ground line via the first Y capacitor CY1 to provide a voltage reference.

[0094] The second end of the secondary side of the first transformer T1 is connected to the neutral point of the first target capacitor module, and the reverse leakage current is injected into the circuit, so that the net leakage current on the ground line approaches zero.

[0095] In the actual implementation process, the power supply device generates excitation, and generates a reverse leakage current through the first transformer T1, the difference of the amplitude of the sampled leakage current does not exceed the target range and the reverse leakage current has the opposite phase, and is injected into the circuit of the charging system through the neutral point of the capacitor module, so that the net leakage current on the ground line approaches 0, thereby achieving leakage current suppression.

[0096] The first target capacitor module may be any capacitor module among the at least one capacitor module.

[0097] For example, Figure 2 As shown, the second end of the secondary side of the first transformer T1 can be connected to the neutral point of the capacitor module arranged before the input of the first sub-filter 21; or as shown in FIG. Figure 3As shown, the second end of the secondary side of the first transformer T1 can be connected to the neutral point of the capacitor module arranged between the output of the first sub-filter 21 and the input of the H-bridge circuit 22; or as shown in FIG. Figure 4 As shown, the second end of the secondary side of the first transformer T1 can be connected to the neutral point of the capacitor module arranged after the input of the H-bridge circuit 22 to inject the reverse leakage current.

[0098] In some embodiments, the active leakage current suppression circuit 40 may further include: a second transformer T2.

[0099] In this embodiment, the second transformer T2 may be connected in series with the first transformer T1 , or may be connected in parallel with the first transformer T1 .

[0100] like Figure 4 As shown, the primary side of the second transformer T2 is arranged between the L line and the N line of the power grid 10 for accessing the alternating current of the power grid 10 .

[0101] The second transformer T2 is used to generate most of the power frequency reverse leakage current.

[0102] The power supply device and the first transformer T1 are used to compensate for the leakage current variation caused by the fluctuation of the Y capacitance of the whole vehicle and the voltage fluctuation of the power grid 10, so as to achieve leakage current suppression.

[0103] Continue to refer Figure 4 When the first transformer T1 and the second transformer T2 are connected in series, the third end of the secondary side of the second transformer T2 is connected to the neutral point of the first target capacitor module, and the fourth end of the secondary side of the second transformer T2 is connected to the second end of the secondary side of the first transformer T1.

[0104] The reverse leakage current is injected into the main circuit through the neutral point of the first target capacitor module connected to the third end of the secondary side of the second transformer T2, thereby achieving leakage current suppression.

[0105] like Figure 5 As shown, when the second transformer T2 is connected in parallel with the first transformer T1, the third end of the secondary side of the second transformer T2 is connected to the neutral point of the second target capacitor module in at least one capacitor module, and the fourth end of the secondary side of the second transformer T2 is connected to the ground line via the second Y capacitor CY2.

[0106] The second target capacitor module may be a capacitor module different from the first target capacitor module among the multiple capacitor modules.

[0107] For example, the third end of the second transformer T2 is connected to the neutral point of the capacitor module arranged before the first sub-filter 21, and the fourth end is connected to the ground line of the power grid 10 via the second Y capacitor CY2; the second end of the first transformer T1 is connected to the neutral point of the capacitor module arranged at the input end and / or output end of the H bridge, and the first end is connected to the ground line of the power grid 10 via the first Y capacitor CY1.

[0108] According to the charging system provided in the embodiment of the present application, by providing a second transformer, accurate suppression of leakage current can be further achieved.

[0109] The structure of the power supply device is described in detail below.

[0110] Continue to refer Figure 4 In some embodiments, the power supply device may include: an active leakage current suppression excitation circuit.

[0111] In this embodiment, the active leakage current suppression excitation circuit is connected to the primary side of the first transformer T1 to provide an excitation source.

[0112] In some embodiments, the power supply device may include: a voltage source module and a first sampling module.

[0113] In this embodiment, the voltage source module is used to provide voltage input and perform voltage conversion.

[0114] The output end of the voltage source module is connected to the primary side of the first transformer.

[0115] The first sampling module is connected to the voltage source module and is used for collecting the leakage current of the ground line and controlling the voltage source module based on the leakage current sampling value.

[0116] The voltage input source of the voltage source module may include: AC input from the power grid 10 , low voltage battery input, and voltage input from the energy storage device 30 .

[0117] The specific structure of the voltage source module may vary depending on the voltage input source. The structure of the voltage source module is described below.

[0118] like Figure 6 As shown, in some embodiments, the voltage source module may include: a first battery, a first high-frequency inverter, a first low-pass filter, and a first filter.

[0119] In this embodiment, the first battery is a low-voltage battery, for example, a 12V or 13.8V storage battery.

[0120] The first filter may include but is not limited to: a π-type filter or other types of EMI filters, etc.

[0121] The first high-frequency inverter is used for converting low-voltage direct current into high-frequency alternating current.

[0122] The first low-pass filter is used to filter the voltage component at the switching frequency and retain the voltage component with a relatively low frequency.

[0123] Continue to refer Figure 6 The first battery, the high-frequency inverter, the low-pass filter and the first filter are connected in series, and the output end of the first filter is connected to the primary side of the first transformer T1.

[0124] The connection method of the secondary side of the first transformer T1 is similar to the above embodiment, for example, it can be connected between the first Y capacitor CY1 and the first target capacitor module to generate reverse leakage current; or it can be connected in series with the second transformer T2, etc., which is not elaborated in this application.

[0125] The first sampling module is connected to the first high-frequency inverter, and is used to collect the leakage current of the ground line, and control the duty cycle of the first high-frequency inverter module based on the sampling value, so as to adjust the frequency and amplitude of the high-frequency AC voltage, generate the corresponding reverse leakage current, and realize accurate suppression of the leakage current.

[0126] In some embodiments, the first sampling module may also include a controller and a leakage current sampling module, wherein the leakage current sampling module is arranged on the ground wire of the power grid 10, and the controller is respectively connected to the high-frequency inverter and the leakage current sampling module, and the controller controls the leakage current sampling module to sample the leakage current on the ground wire, and determines the duty cycle of the first high-frequency inverter through feedback control, thereby adjusting the frequency and amplitude of the high-frequency AC voltage.

[0127] like Figure 7 As shown, in some embodiments, the voltage source module may include: a rectifier circuit, a first DC / DC converter, a second high-frequency inverter, a second low-pass filter, and a second filter.

[0128] In this embodiment, the rectifier circuit, the first DC / DC converter, the second high-frequency inverter, the second low-pass filter and the second filter are connected in sequence, and the input end of the rectifier circuit is used to access the AC power of the power grid 10.

[0129] The rectifier circuit is used to convert the AC voltage of the power grid 10 into a high-voltage DC voltage.

[0130] The first DC / DC converter is a DC-to-DC converter, which is used to convert high-voltage DC power into low-voltage DC power.

[0131] The second high-frequency inverter is used to convert the low-voltage direct current into high-frequency alternating current.

[0132] The second low-pass filter is used to filter the voltage component at the switching frequency in the high-frequency alternating current and retain the voltage component at a relatively low frequency.

[0133] The second filter may include but is not limited to: a π-type filter or other types of EMI filters, etc.

[0134] The output end of the second filter is connected to the primary side of the first transformer T1.

[0135] The first sampling module is used to collect the leakage current of the ground line and control the high-frequency inverter based on the leakage current sampling value.

[0136] The connection method and control logic of the first sampling module have been described in the above embodiments and will not be described again here.

[0137] like Figure 8 As shown, in some embodiments, the voltage source module may include: a second DC / DC converter, a third high-frequency inverter, a third low-pass filter, and a third filter.

[0138] In this embodiment, the second DC / DC converter, the third high-frequency inverter, the third low-pass filter and the third filter are connected in sequence, and the input end of the second DC / DC converter is connected to the two ends of the energy storage device 30, and the high-voltage direct current output by the energy storage device 30 is used as an excitation source for the active leakage current suppression circuit 40.

[0139] The second DC / DC converter is used to convert the high-voltage direct current provided by the energy storage device 30 into low-voltage direct current.

[0140] In some embodiments, the third filter may include, but is not limited to, a π-type filter or other types of EMI filters.

[0141] The connection mode and specific execution logic corresponding to the third high-frequency inverter, the third low-pass filter, the third filter and the first sampling module are similar to those in the above embodiment, and are not elaborated herein in this application.

[0142] like Fig. 9 As shown, in some embodiments, the power supply device may further include: a third DC / DC converter, a fourth high-frequency inverter, a fourth low-pass filter, a fourth filter and a second sampling module.

[0143] In this embodiment, the input end of the third DC / DC converter is connected to the two ends of the energy storage device 30 , and the high voltage direct current output by the energy storage device 30 is used as an excitation source for the active leakage current suppression circuit 40 .

[0144] The third DC / DC converter, the fourth high-frequency inverter, the fourth low-pass filter and the fourth filter are connected in sequence.

[0145] In some embodiments, the fourth filter may include, but is not limited to: a π-type filter or other types of EMI filters, etc.

[0146] The first output end of the fourth filter is connected to the ground line via the first Y capacitor CY1, and the second output end of the fourth filter is connected to the neutral point of the first target capacitor module.

[0147] For example, the second output end of the fourth filter may be connected to the neutral point of the capacitor module before the first sub-filter 21 , or may be connected to the neutral points of the capacitor modules before and after the H-bridge circuit 22 .

[0148] The second sampling module is connected to the fourth high-frequency inverter and controls the fourth high-frequency inverter based on the ground wire leakage current sampling value.

[0149] The second sampling module may further include a controller and a leakage current sampling module. The specific configuration is similar to that of the first sampling module, and will not be elaborated herein.

[0150] According to the charging system provided in the embodiment of the present application, reverse leakage current injection can be directly implemented through the first Y capacitor without the aid of a transformer, thereby further reducing system components and reducing the cost of the leakage current suppression circuit.

[0151] like Figure 1 and Fig.10 As shown, in some embodiments, the system may further include: a switch module 50 and a third switch K61.

[0152] In this embodiment, the switch module includes: a plurality of first switches, a second switch and a plurality of fourth capacitors.

[0153] Therein, at least one first switch is respectively provided in each phase line and neutral line of the power grid 10 , and when the first switch is closed, the branch circuit provided by the first switch is turned on.

[0154] One end of the second switch is arranged between the first switch corresponding to the neutral line of the grid 10 and the N-phase port of the grid 10 , and the other end of the second switch is arranged between the first switch corresponding to any phase line of the grid 10 and the non-isolated charger 20 .

[0155] The fourth capacitor is arranged between the target phase line and the neutral line.

[0156] The target phase line includes at least one phase line among the A phase line, the B phase line and the C phase line.

[0157] The third switch K61 is disposed between the active leakage current suppression circuit 40 and the non-isolated charger 20 .

[0158] Continue to refer Fig.10 The third switch K61 may be connected between the second end of the secondary side of the first transformer T1 and the fourth capacitor.

[0159] Continue to refer Fig.10 For example, when the active leakage current suppression circuit 40 includes a first transformer T1, a power supply device and a first Y capacitor CY1, the first end of the secondary side of the first transformer T1 is connected to the ground line via the first Y capacitor CY1, and the second end of the secondary side is connected to the first end of each fourth capacitor via the third switch K61.

[0160] The power supply device may be any form such as the active leakage current suppression excitation circuit proposed in the above embodiments, the first battery, the alternating current of the power grid 10 or the output of the energy storage device 30 .

[0161] In other embodiments, the active leakage current suppression circuit 40 may also be as follows: Fig. 9 The circuit structure shown is not limited in this application.

[0162] For example, continue to refer to Fig.10 The first switch may include: switch K51, switch K52, switch K53, switch K54, etc.

[0163] When the switch K51, the second switch K55 and the third switch K61 are closed, the circuit works in the single-phase input mode. At this time, the active leakage current suppression circuit 40 is connected to suppress the power frequency and high frequency leakage current in the single-phase input mode.

[0164] When switches K51, K52, K53 and K54 are closed, the circuit operates in a three-phase input mode. The fluctuation of the battery voltage to ground can be suppressed by optimizing the control strategy. The active leakage current suppression circuit 40 does not need to work and is therefore not connected. The high-frequency leakage current can be suppressed by the common-mode inductance in the first sub-filter 21 and the second sub-filter 23 included in the non-isolated charger 20.

[0165] According to the charging system provided in the embodiment of the present application, by setting multiple switches, compatibility with single-phase input and three-phase input can be achieved, further improving the applicable scenarios and scope of the charging system.

[0166] The embodiment of the present application also provides an energy storage system.

[0167] The energy storage system comprises: an energy storage device 30 and a charging system as described in any of the above embodiments.

[0168] In this embodiment, the charging system is connected to the energy storage device 30 .

[0169] According to the energy storage system provided in the embodiment of the present application, an active leakage current suppression circuit 40 independent of the control logic of the original circuit is provided to generate a reverse leakage current with a difference in amplitude from the leakage current in the circuit of the charging system not exceeding a target range and with an opposite phase, which is injected into the circuit of the charging system, so that the net leakage current on the ground line approaches 0, thereby effectively achieving leakage current suppression, and the system has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

[0170] An embodiment of the present application also provides a vehicle.

[0171] The vehicle comprises an energy storage system as described in any of the above embodiments.

[0172] In this embodiment, the energy storage system is disposed on the vehicle body to supply power to the vehicle.

[0173] According to the vehicle provided in the embodiment of the present application, an active leakage current suppression circuit 40 is set up with a control logic independent of the original circuit to generate a reverse leakage current with a difference in amplitude from the leakage current in the circuit of the charging system not exceeding a target range and with an opposite phase, which is injected into the circuit of the charging system, so that the net leakage current on the ground wire approaches 0, thereby effectively achieving leakage current suppression, and the invention has a simple structure, low control complexity, low design cost, high reliability and a wide range of applicable scenarios.

[0174] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0175] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a magnetic disk, or an optical disk), and includes a number of instructions for enabling a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0176] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0177] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0178] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A charging system, characterized in that: include: A non-isolated charger, wherein the non-isolated charger is connected between the power grid and the energy storage device, and at least one capacitor module is provided between the phase line and the neutral line of the non-isolated charger; An active leakage current suppression circuit, the active leakage current suppression circuit comprising a power supply device, the active leakage current suppression circuit being respectively connected to the ground line of the power grid and the neutral point of the first target capacitor module in the at least one capacitor module; the power supply device being used to provide power excitation to the active leakage current suppression circuit so that the active leakage current suppression circuit generates a reverse leakage current whose amplitude difference from the leakage current in the charging system does not exceed a target range and whose phase is opposite; The active leakage current suppression circuit includes a first Y capacitor, and the first Y capacitor is connected to the ground line; The power supply device is connected in series with the first Y capacitor.

2. The charging system according to claim 1, characterized in that: The active leakage current suppression circuit further includes: A first transformer, wherein the primary side of the first transformer is connected to the power supply device, the first end of the secondary side of the first transformer is connected to the ground wire via the first Y capacitor, and the second end of the secondary side of the first transformer is connected to the neutral point of the first target capacitor module.

3. The charging system according to claim 2, characterized in that: The active leakage current suppression circuit further includes: a second transformer, The primary side of the second transformer is used to access the power grid, and the second transformer and the first transformer are connected in series or in parallel, wherein: In the case where the first transformer is connected in series with the second transformer, the third end of the secondary side of the second transformer is connected to the neutral point of the first target capacitor module, and the fourth end of the secondary side of the second transformer is connected to the second end of the secondary side of the first transformer; When the first transformer is connected in parallel with the second transformer, the third end of the secondary side of the second transformer is connected to the neutral point of the second target capacitor module in the at least one capacitor module, and the fourth end of the secondary side of the second transformer is connected to the ground line via a second Y capacitor.

4. The charging system according to claim 2, characterized in that: The power supply device includes: an active leakage current suppression excitation circuit, and the active leakage current suppression excitation circuit is connected to the primary side of the first transformer.

5. The charging system according to claim 2, characterized in that: The power supply device comprises: A voltage source module, wherein an output end of the voltage source module is connected to a primary side of the first transformer; A first sampling module, wherein the first sampling module is connected to the voltage source module and is used to collect a leakage current of the ground line and control the voltage source module based on the leakage current.

6. The charging system according to claim 5, characterized in that: The voltage source module comprises: A first battery, a first high-frequency inverter, a first low-pass filter and a first filter, wherein the output end of the first filter is connected to the primary side of the first transformer; and the first sampling module is connected to the first high-frequency inverter.

7. The charging system according to claim 5, characterized in that: The voltage source module comprises: A rectifier circuit, a first DC / DC converter, a second high-frequency inverter, a second low-pass filter and a second filter, wherein the output end of the second filter is connected to the primary side of the first transformer, and the rectifier circuit is connected to the power grid; the first sampling module is connected to the second high-frequency inverter.

8. The charging system according to claim 5, characterized in that: The voltage source module comprises: A second DC / DC converter, a third high-frequency inverter, a third low-pass filter and a third filter, wherein the output end of the third filter is connected to the primary side of the first transformer, and the input end of the second DC / DC converter is connected to the two ends of the energy storage device; the first sampling module is connected to the third high-frequency inverter.

9. The charging system according to claim 1, characterized in that: The power supply device comprises: A third DC / DC converter, a fourth high-frequency inverter, a fourth low-pass filter and a fourth filter, wherein a first output end of the fourth filter is connected to the ground line via a first Y capacitor included in the active leakage current suppression circuit, a second output end of the fourth filter is connected to a neutral point of the first target capacitor module, and an input end of the third DC / DC converter is connected to two ends of the energy storage device; A second sampling module connected to the fourth high-frequency inverter, the second sampling module is used to collect a leakage current of the ground line and control the fourth high-frequency inverter based on the leakage current.

10. The charging system according to any one of claims 1 to 9, characterized in that: The non-isolated charger comprises: a first sub-filter, an H-bridge circuit and a second sub-filter, wherein: The input end of the first sub-filter is used to access the power grid; the output end of the second sub-filter is connected to the energy storage device; The capacitor module is arranged before the input end of the first sub-filter, or between the first sub-filter and the H-bridge circuit, or after the output end of the H-bridge circuit, or after the second sub-filter.

11. The charging system according to any one of claims 1 to 9, characterized in that: Also includes: A switch module, wherein the switch module is arranged between the phase line and the neutral line of the power grid and the non-isolated charger; A third switch is provided between the active leakage current suppression circuit and the non-isolated charger.

12. An energy storage system, characterized in that: include: Energy storage devices; The charging system according to any one of claims 1 to 11, wherein the charging system is connected to the energy storage device.

13. A vehicle, characterized in that: include: The energy storage system as claimed in claim 12.

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