Adjustable filter circuit, energy storage unit and energy storage system

Abstract

The utility model provides an adjustable filter circuit, an energy storage unit and an energy storage system.The adjustable filter circuit is arranged on the energy storage unit and / or arranged on a single-phase bridge arm of the energy storage system.The adjustable filter circuit comprises a first multi-selection switch and a plurality of first filter sub-circuits, the plurality of first filtering sub-circuits correspond to different filtering frequency ranges, the first multi-selection switch comprises a plurality of first switching contacts, and one first switching contact of the first multi-selection switch is correspondingly connected with one first filtering sub-circuit.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage systems, and in particular to an adjustable filter circuit, an energy storage unit and an energy storage system. Background Art

[0002] In the MMC energy storage system, filtering circuits are required on both the DC and AC sides. However, in traditional energy storage systems, filtering circuits are usually configured as a single filtering circuit based on the application scenario. When the application scenario changes, the filtering circuit needs to be reconfigured. Traditional energy storage systems cannot replace filtering circuits online, resulting in the system being unable to operate normally. Utility Model Content

[0003] In view of this, the purpose of the present application is to provide an adjustable filter circuit, an energy storage unit and an energy storage system, which can be configured by arranging an adjustable filter circuit on a single-phase bridge arm of the energy storage unit and / or the energy storage system, wherein the adjustable filter circuit includes a first multiple-selection switch and a plurality of first filter sub-circuits, wherein the plurality of first filter sub-circuits correspond to different filter frequency ranges, and each switching contact of the first multiple-selection switch is connected to a first filter sub-circuit, so that different switching contacts of the multiple-selection switch are selected to be connected to the single-phase bridge arm of the energy storage unit and / or the energy storage system to adjust different filter frequency ranges of the adjustable filter circuit, thereby solving the technical problem in the prior art that the filter circuit arranged between the battery and the bridge circuit cannot perform frequency modulation, and achieving the technical effect of increasing the applicable scenarios of the energy storage system.

[0004] In a first aspect, an embodiment of the present application provides an adjustable filter circuit, which is arranged on an energy storage unit and / or on a single-phase bridge arm of an energy storage system. The adjustable filter circuit includes a first multiple-selection switch and a plurality of first filter sub-circuits, and the plurality of first filter sub-circuits correspond to different filter frequency ranges, wherein the first multiple-selection switch includes a plurality of first switching contacts, and a first switching contact of the first multiple-selection switch corresponds to a connection with a first filter sub-circuit.

[0005] Optionally, the adjustable filter circuit also includes a second filter sub-circuit, wherein the first multiple-selection switch and the multiple first filter sub-circuits are arranged on a first power transmission line, and a second filter sub-circuit is arranged on a second power transmission line led out from a first target end of the first power transmission line, and the first target end is located at one end of the first power transmission line close to the first multiple-selection switch or close to one end of the multiple first filter sub-circuits.

[0006] Optionally, the adjustable filter circuit further includes a plurality of second filter sub-circuits, one second filter sub-circuit corresponding to one first filter sub-circuit, wherein the first multiple-selection switch and the plurality of first filter sub-circuits are arranged on a first power transmission line, a second filter sub-circuit is led out from a second target end of a corresponding first filter sub-circuit, the plurality of second filter sub-circuits are all connected to the second power transmission line, and the second target end is located at an end of the first filter sub-circuit away from the first multiple-selection switch.

[0007] Optionally, each first filtering subcircuit includes a first filter and a second filter, the first filter is one of a resistor and a capacitor, and the second filter is the other of a resistor and a capacitor. For each first filtering subcircuit, the first filter of the first filtering subcircuit is arranged on a first power transmission line, a second power transmission line is led out from the first power transmission line, and the second filter of the first filtering subcircuit is arranged on the second power transmission line, and a switching contact corresponding to the first filtering subcircuit is connected to the first filter or the second filter.

[0008] Optionally, the first filtering subcircuit includes one of a resistor and a capacitor, and the second filtering subcircuit includes the other of a resistor and a capacitor.

[0009] Optionally, the energy storage unit includes a battery and a bridge circuit, and the adjustable filter circuit is arranged between the battery and the bridge circuit, wherein the first power transmission line refers to a first preset power transmission line between the positive electrode of the battery and one end of the DC side of the bridge circuit or a second preset power transmission line between the negative electrode of the battery and the other end of the DC side of the bridge circuit, and the second power transmission line is arranged between the first preset power transmission line and the second preset power transmission line.

[0010] Optionally, the adjustable filter circuit is arranged on the single-phase bridge arm of the energy storage system, the first power transmission line refers to a power transmission line led out from the input and output interface of the single-phase bridge arm, the input and output interface is used to connect an external electrical device or an external power supply device, and the second power transmission line refers to a power transmission line led out from the first power transmission line and used to connect multiple energy storage units connected in series.

[0011] In a second aspect, an embodiment of the present application further provides an energy storage unit, comprising: a battery; a bridge circuit, the AC side of the bridge circuit being used to connect to the bus of a single-phase bridge arm of an energy storage system; and an adjustable filter circuit as described in the above-mentioned first aspect or any possible implementation manner of the first aspect, wherein the adjustable filter circuit is arranged between the battery and the DC side of the bridge circuit.

[0012] Optionally, the bridge circuit includes a first control switch, a second control switch, a third control switch and a fourth control switch, wherein one end of the first control switch is connected to one end of the second control switch, the other end of the first control switch is connected to one end of the third control switch, the other end of the second control switch is connected to one end of the fourth control switch, and the other end of the third control switch is connected to the other end of the fourth control switch.

[0013] Optionally, the connection between the first control switch and the second control switch serves as one end of the DC side of the bridge circuit, the connection between the third control switch and the fourth control switch serves as the other end of the DC side of the bridge circuit, and the connection between the first control switch and the third control switch and the connection between the second control switch and the fourth control switch serve as the AC side of the bridge circuit.

[0014] In a third aspect, an embodiment of the present application further provides an energy storage system, comprising a single-phase bridge arm, wherein the single-phase bridge arm comprises: an input-output interface, wherein the input-output interface is used to connect an external electrical device or an external power supply device; a plurality of energy storage units, wherein the plurality of energy storage units are sequentially connected in series to a busbar of the single-phase bridge arm and are charged and discharged through the input-output interface; wherein an adjustable filter circuit as described in the first aspect or any possible implementation manner of the first aspect is arranged between the input-output interface and the busbar of the single-phase bridge arm, and / or at least one energy storage unit comprises an adjustable filter circuit as described in the first aspect or any possible implementation manner of the first aspect.

[0015] In a fourth aspect, an embodiment of the present application further provides an energy storage system, wherein the energy storage system includes a three-phase bridge arm, wherein each single-phase bridge arm in the three-phase bridge arm includes: an input-output interface, wherein the input-output interface is used to connect an external electrical device or an external power supply device; a plurality of energy storage units, wherein the plurality of energy storage units are sequentially connected in series to a busbar of the single-phase bridge arm and are charged and discharged through the input-output interface; wherein an adjustable filter circuit as described in the first aspect or any possible implementation manner of the first aspect is arranged between the input-output interface of at least one single-phase bridge arm and the busbar of the single-phase bridge arm, and / or at least one energy storage unit corresponding to at least one single-phase bridge arm includes an adjustable filter circuit as described in the first aspect or any possible implementation manner of the first aspect.

[0016] Optionally, at least one single-phase bridge arm in the three-phase bridge arm also includes a single-pole multi-throw switch and a control module, the single-pole multi-throw switch includes multiple branches, and for each branch, the branch is a clear branch or a connected protection circuit, wherein the control module is configured to: control the clear branch of the single-pole multi-throw switch to connect to the single-phase bridge arm or control the branch of the single-pole multi-throw switch connected to the protection circuit to connect to the single-phase bridge arm.

[0017] Optionally, the adjustable filter circuit is set on the target single-phase bridge arm in the three-phase bridge arm, the target single-phase bridge arm includes a control module, and the first multiple-selection switch and / or the second multiple-selection switch in the adjustable filter circuit include at least one idle switching contact, wherein the control module is configured to: control the idle switching contact in the first multiple-selection switch or the second multiple-selection switch in the adjustable filter circuit to be empty or control the adjustable filter circuit to connect to the target single-phase bridge arm.

[0018] The embodiment of the present application provides an adjustable filter circuit, an energy storage unit and an energy storage system, wherein the adjustable filter circuit is arranged on the energy storage unit and / or on the single-phase bridge arm of the energy storage system, wherein the adjustable filter circuit includes a first multiple-selection switch and a plurality of first filter sub-circuits, wherein the plurality of first filter sub-circuits correspond to different filter frequency ranges, wherein the first multiple-selection switch includes a plurality of first switching contacts, and a first switching contact of the first multiple-selection switch is connected to a corresponding first filter sub-circuit. By arranging an adjustable filter circuit on the single-phase bridge arm of the energy storage unit and / or the energy storage system, the adjustable filter circuit includes a first multiple-selection switch and a plurality of first filter sub-circuits, wherein the plurality of first filter sub-circuits correspond to different filter frequency ranges, and each switching contact of the first multiple-selection switch is connected to a first filter sub-circuit, so that different switching contacts of the multiple-selection switch are selected to be connected to the single-phase bridge arm of the energy storage unit and / or the energy storage system, to adjust the different filter frequency ranges of the adjustable filter circuit, the technical problem that the filter circuit arranged between the battery and the bridge circuit in the prior art cannot perform frequency modulation is solved, and the technical effect of increasing the applicable scenarios of the energy storage system is achieved.

[0019] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 A schematic structural diagram of an adjustable filter circuit provided in an embodiment of the present application is shown.

[0022] Figure 2 A schematic diagram showing the setting position of an adjustable filter circuit provided in an embodiment of the present application is shown.

[0023] Figure 3 The circuit diagram of an adjustable filter circuit provided by an embodiment of the present application is shown. Figure 1 .

[0024] Figure 4 The circuit diagram of an adjustable filter circuit provided by an embodiment of the present application is shown. Figure 2 .

[0025] Figure 5 The circuit diagram of an adjustable filter circuit provided by an embodiment of the present application is shown. Figure 3 .

[0026] Figure 6 The circuit diagram of an adjustable filter circuit provided by an embodiment of the present application is shown. Figure 4 .

[0027] Figure 7 A schematic diagram of an energy storage unit provided in an embodiment of the present application is shown Figure 1 .

[0028] Figure 8 A schematic diagram of an energy storage unit provided in an embodiment of the present application is shown Figure 2 .

[0029] Fig. 9 A schematic diagram of an energy storage system provided in an embodiment of the present application is shown.

[0030] Fig.10 A schematic diagram of another energy storage system provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0031] To make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application usually described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work belongs to the scope of protection of the present application.

[0032] In the prior art, the filter circuit between the battery side and the AC side of the energy storage unit is composed of fixed filter components. In some application scenarios, the filter circuit cannot protect the battery well.

[0033] In view of the above problems, the embodiments of the present application provide an adjustable filter circuit, an energy storage unit and an energy storage system. By setting an adjustable filter circuit on the single-phase bridge arm of the energy storage unit and / or the energy storage system, the adjustable filter circuit includes a first multiple-selection switch and multiple first filter sub-circuits, and the multiple first filter sub-circuits correspond to different filter frequency ranges. Each switching contact of the first multiple-selection switch is connected to a first filter sub-circuit, so that different switching contacts of the multiple-selection switch are selected to be connected to the single-phase bridge arm of the energy storage unit and / or the energy storage system to adjust the different filter frequency ranges of the adjustable filter circuit, which solves the technical problem that the filter circuit set between the battery and the bridge circuit in the prior art cannot perform frequency modulation, and achieves the technical effect of increasing the applicable scenarios of the energy storage system, which is specifically as follows:

[0034] See also Figure 1 , Figure 1 A schematic diagram of a structure of an adjustable filter circuit provided in an embodiment of the present application is shown in FIG. Figure 1 As shown, the adjustable filter circuit includes a first multiple-selection switch K1 and multiple first filter sub-circuits 101, and the multiple first filter sub-circuits correspond to different filter frequency ranges, wherein the first multiple-selection switch includes multiple first switching contacts, and one first switching contact of the first multiple-selection switch is correspondingly connected to one first filter sub-circuit.

[0035] See also Figure 2 , Figure 2 The schematic diagram of the setting position of the adjustable filter circuit provided in the embodiment of the present application is as follows: Figure 2 As shown, the adjustable filter circuit 100 is arranged on an energy storage unit and / or on a single-phase bridge arm of an energy storage system.

[0036] That is to say, the control module of the energy storage system controls any one of the first switching contacts of the first multi-select switch to be turned on, changes the filter subcircuit connected to the energy storage unit and / or arranged on the single-phase bridge arm of the energy storage system, and then changes the filter frequency range of the adjustable filter circuit, thereby increasing the applicable scenarios of the energy storage unit and / or the energy storage system.

[0037] Specifically, the control module determines the voltage and current on the busbar of the single-phase bridge arm according to the voltage and current required by the electrical load connected to the energy storage system, and determines the filtering frequency required for each energy storage unit on the single-phase bridge arm. Therefore, when an adjustable filter circuit is set on the single-phase bridge arm, the most suitable target first filter subcircuit is selected in combination with the filtering frequency ranges corresponding to the multiple first filter subcircuits, and then the first switching contact corresponding to the target first filter subcircuit is controlled to be turned on, so that the single-phase bridge arm is connected through the target first filter subcircuit; when an adjustable filter circuit is set on the energy storage unit, the most suitable target first filter subcircuit is selected in combination with the filtering frequency ranges corresponding to the multiple first filter subcircuits, and then the first switching contact corresponding to the target first filter subcircuit is controlled to be turned on, so that the energy storage unit is connected through the target first filter subcircuit. Then, the voltage and current flowing through the single-phase bridge arm are filtered to protect the single-phase bridge arm, and / or the voltage and current of the battery flowing through the energy storage unit are filtered to protect the battery.

[0038] Exemplarily, the first multiple-selection switch may be a single-pole multi-throw switch, and further, the first multiple-selection switch further includes a fixed terminal, and the conduction at the target first switching contact of the first multiple-selection switch means that the fixed terminal of the first multiple-selection switch is only conducted with the target first switching contact.

[0039] Specifically, the adjustable filter circuit further includes a second filter subcircuit, wherein one of the first filter subcircuit and the second filter subcircuit serves as a first target filter subcircuit, the other of the first filter subcircuit and the second filter subcircuit serves as a second target filter subcircuit, the first target filter subcircuit includes a resistor, and the second target filter subcircuit includes a capacitor. The first target filter subcircuit is arranged on a first power transmission line, and on a second power transmission line derived from the first power transmission line, the second target filter subcircuit is arranged on the second power transmission line.

[0040] For example, see Figure 3 , Figure 3 The circuit of the adjustable filter circuit provided in the embodiment of the present application Figure 1 .like Figure 3 As shown, the adjustable filter circuit includes a first multiple-selection switch K1, multiple first filter sub-circuits 1011 and a second filter sub-circuit 2011, wherein the first filter sub-circuit includes a resistor R1, and the second filter sub-circuit includes a capacitor C1. Furthermore, the first filter sub-circuit serves as a first target filter sub-circuit, and the second filter sub-circuit serves as a second target filter sub-circuit. Multiple first filter sub-circuits are arranged on a first power transmission line, a second power transmission line is led out from the first power transmission line, and a second filter sub-circuit is arranged on the second power transmission line.

[0041] That is to say, different first filter subcircuits correspond to different resistors. Each first switching contact of the first multiple-selection switch is connected to a resistor, and then, when the resistor that best matches the capacitor C1 in a second filter subcircuit is determined, the first switching contact corresponding to the best-matching resistor of the first multiple-selection switch is controlled to be turned on, so that the second resistor that best matches the capacitor is selected to be connected to the adjustable filter circuit, so as to change the frequency modulation range of the adjustable filter circuit.

[0042] For example, see Figure 4 , Figure 4 A circuit of an adjustable filter circuit provided in an embodiment of the present application Figure 2 .like Figure 4 As shown, the adjustable filter circuit includes a first multiple-selection switch K2, multiple first filter sub-circuits 1012 and a second filter sub-circuit 2012, wherein the first filter sub-circuit includes a capacitor C2, and the second filter sub-circuit includes a resistor R2. Furthermore, the second filter sub-circuit serves as a first target filter sub-circuit, and the first filter sub-circuit serves as a second target filter sub-circuit. A second filter sub-circuit is arranged on a first power transmission line, and a second power transmission line is led out from the first power transmission line. Multiple first filter sub-circuits are arranged on the second power transmission line.

[0043] That is to say, different first filter subcircuits correspond to different capacitors. Each first switching contact of the first multiple-selection switch is connected to a capacitor, and then, when the capacitor that best matches the resistor of a second filter subcircuit is determined, the first switching contact of the first multiple-selection switch corresponding to the best-matching capacitor is controlled to be turned on, so that the capacitor that best matches the resistor is selected to be connected to the adjustable filter circuit, so as to change the frequency modulation range of the adjustable filter circuit.

[0044] Specifically, the adjustable filter circuit further includes a plurality of second filter subcircuits, wherein one of the first filter subcircuit and the second filter subcircuit serves as a first target filter subcircuit, another of the first filter subcircuit and the second filter subcircuit serves as a second target filter subcircuit, the first target filter subcircuit includes a resistor, and the second target filter subcircuit includes a capacitor. The first target filter subcircuit is arranged on a first power transmission line, and on a second power transmission line derived from the first power transmission line, the second target filter subcircuit is arranged on the second power transmission line.

[0045] The adjustable filter circuit also includes a second multiple-selection switch connected to a plurality of second filter sub-circuits, the second multiple-selection switch includes a plurality of second switching contacts, and one second switching contact of the second multiple-selection switch is correspondingly connected to one second filter sub-circuit.

[0046] Specifically, the adjustable filter circuit further includes a second multiple-selection switch and a plurality of second filter subcircuits, the plurality of second filter subcircuits correspond to different filter frequency ranges, the second multiple-selection switch includes a plurality of second switching contacts, and one second switching contact of the second multiple-selection switch is connected to a corresponding second filter subcircuit. Among them, the filter subcircuit including a resistor among the plurality of first filter subcircuits and the plurality of second filter subcircuits is arranged on the first power transmission line, and the filter subcircuit including a capacitor among the plurality of first filter subcircuits and the plurality of second filter subcircuits is arranged on the second power transmission line derived from the first power transmission line.

[0047] That is to say, multiple filter subcircuits can be set on both the first power transmission line and the second power transmission line, and then, the devices connected to the first power transmission line and the second power transmission line are all selectable. Therefore, after determining the filter frequency required by the adjustable filter circuit, the control module of the energy storage system can select the most suitable resistors and capacitors according to the component parameters corresponding to the multiple first filter subcircuits and the multiple third filter subcircuits, and then select the most suitable resistors and capacitors to connect to the adjustable filter circuit.

[0048] For example, see Figure 5 , Figure 5 A circuit of an adjustable filter circuit provided in an embodiment of the present application Figure 3 .like Figure 5 As shown, the adjustable filter circuit includes a first multiple-selection switch K31, a plurality of first filter subcircuits 1013, a second multiple-selection switch K32, and a plurality of second filter subcircuits 2013. The first filter subcircuit includes a resistor R3, and the second filter subcircuit includes a capacitor C3. Furthermore, the first filter subcircuit serves as a first target filter subcircuit, and the second filter subcircuit serves as a second target filter subcircuit. The plurality of first filter subcircuits are all arranged on a first power transmission line, and a second power transmission line is led out from the first power transmission line. The plurality of second filter subcircuits are all arranged on the second power transmission line.

[0049] That is to say, different first filter subcircuits correspond to different resistors, and different second filter subcircuits correspond to different capacitors. Furthermore, the resistor of the adjustable filter circuit can be selected by controlling the first multiple-selection switch, and the capacitor of the adjustable filter circuit can be selected by controlling the second multiple-selection switch, so that the filter frequency range of the adjustable filter circuit can be changed through different combinations of resistors and capacitors to increase the applicable scenarios of the energy storage system.

[0050] Each first filtering sub-circuit includes a resistor and a capacitor. For each first filtering sub-circuit, the resistor of the first filtering sub-circuit is arranged on the first power transmission line, and the second power transmission line is led out from the first power transmission line. The capacitor of the first filtering sub-circuit is arranged on the second power transmission line, and each first switching contact of the first multiple-selection switch corresponds to the resistor or capacitor connected to the first filtering sub-circuit.

[0051] For example, see Figure 6 , Figure 6 A circuit of an adjustable filter circuit provided in an embodiment of the present application Figure 4 .like Figure 6 As shown, the adjustable filtering energy storage unit includes a first multiple-selection switch K4 and a plurality of first filtering sub-circuits 1014, each of which includes a resistor R4 and a first capacitor C4. For each first filtering sub-circuit, the resistor of the first filtering sub-circuit is arranged on the first power transmission line, and a second power transmission line is led out from one end of the resistor. The capacitor of the first filtering sub-circuit is arranged on the second power transmission line, and each first switching contact of the first multiple-selection switch K4 is connected to a corresponding resistor.

[0052] That is to say, different first filter subcircuits correspond to different combinations of resistors and capacitors, so that each first filter subcircuit corresponds to a different filter frequency range. The first multiple-selection switch and the resistor of each first filter subcircuit are arranged on the first power transmission line, the resistor of each first filter subcircuit is led out to the second power transmission line, and the capacitor is arranged on the second power transmission line. Furthermore, by controlling the conduction of different first switching contacts of the first multiple-selection switch, different combinations of resistors and capacitors are selected to be connected to the adjustable filter circuit, thereby increasing the applicable scenarios of the energy storage system.

[0053] Exemplarily, the resistor of the present application includes at least one resistor and / or at least one inductor.

[0054] Specifically, if the adjustable filter circuit is set on the energy storage unit, the energy storage unit includes a battery and a bridge circuit, and the adjustable filter circuit is set between the battery and the bridge circuit, wherein the first power transmission line refers to the first preset power transmission line between the positive pole of the battery and one end of the DC side of the bridge circuit or the second preset power transmission line between the negative pole of the battery and the other end of the DC side of the bridge circuit, and the second power transmission line is set between the first preset power transmission line and the second preset power transmission line.

[0055] That is to say, the adjustable filter circuit can adjust different filter frequency ranges. By setting the adjustable filter circuit between the battery and the DC side of the bridge circuit, the filter frequency between the battery and the DC side of the bridge circuit is modulated, thereby changing the filter frequency of the current and voltage flowing through the battery, thereby improving the applicable scenarios of the energy storage system and increasing the filtering effect of the energy storage unit. In addition, the filter subunit where the control resistor is located is set between the battery and the DC side of the bridge circuit, and the filter subunit where the control capacitor is located is set between the first preset power transmission line and the second preset power transmission line to achieve modulation of the filter frequency between the battery and the DC side of the bridge circuit.

[0056] Furthermore, the adjustable filter circuit of the energy storage unit can be Figures 3 to 6 For any of the adjustable filter circuits, it is only necessary to control the resistor in the filter circuit to be set on the first preset power transmission line between the positive electrode of the battery and one end of the DC side of the bridge circuit or the second preset power transmission line between the negative electrode of the battery and the other end of the DC side of the bridge circuit, and control the capacitor in the filter circuit to be set between the first preset power transmission line and the second preset power transmission line to realize resistor-capacitor filtering.

[0057] For example, see Figure 7 , Figure 7 A schematic diagram of an energy storage unit provided in an embodiment of the present application Figure 1 .like Figure 7 As shown, the energy storage unit is arranged on the single-phase bridge arm of the energy storage system, including a battery BAT; a bridge circuit 102, the AC side of the bridge circuit is used to connect to the bus BUS of the single-phase bridge arm; an adjustable filter circuit 100 is arranged between the battery and the DC side of the bridge circuit to modulate the filter frequency between the battery and the DC side of the bridge circuit. The adjustable filter circuit 100 includes a first multiple-selection switch K1, a plurality of first filter subcircuits and a second filter subcircuit, wherein the first filter subcircuit includes a resistor R1, and the second filter subcircuit includes a capacitor C1, and further, the first multiple-selection switch and the plurality of first filter subcircuits are arranged on a first preset power transmission line between the positive pole of the battery and one end of the DC side of the bridge circuit, and the second filter subcircuit is arranged between the first preset power transmission line and the second preset power transmission line.

[0058] The bridge circuit includes a first control switch, a second control switch, a third control switch and a fourth control switch, wherein one end of the first control switch is connected to one end of the second control switch, the other end of the first control switch is connected to one end of the third control switch, the other end of the second control switch is connected to one end of the fourth control switch, and the other end of the third control switch is connected to the other end of the fourth control switch.

[0059] The connection between the first control switch and the second control switch serves as one end of the DC side of the bridge circuit, the connection between the third control switch and the fourth control switch serves as the other end of the DC side of the bridge circuit, and the connection between the first control switch and the third control switch and the connection between the second control switch and the fourth control switch serve as the AC side of the bridge circuit.

[0060] For example, see Figure 8 , Figure 8 A schematic diagram of an energy storage unit provided in an embodiment of the present application Figure 2 .like Figure 8 As shown, the bridge circuit 102 includes a first control switch Q1, a second control switch Q2, a third control switch Q3 and a fourth control switch Q4, wherein one end of the first control switch is connected to one end of the second control switch, the other end of the first control switch is connected to one end of the third control switch, the other end of the second control switch is connected to one end of the fourth control switch, and the other end of the third control switch is connected to the other end of the fourth control switch. The connection between the first control switch and the second control switch is connected to the positive electrode of the battery through a filter circuit, the connection between the third control switch and the fourth control switch is connected to the negative electrode of the battery through a filter circuit, the connection between the first control switch and the third control switch leads to a first busbar connected to a single-phase bridge arm, and the connection between the second control switch and the fourth control switch leads to a second busbar connected to a single-phase bridge arm.

[0061] Among them, the switching state of the four control switches in the bridge circuit is used to control whether the battery is connected to the bus of the single-phase bridge arm, and the positive and negative voltage values ​​on the AC side of the bridge circuit can be changed, that is, the battery can be connected to the bus in the forward direction, the reverse direction, the forward bypass, and the reverse bypass. When the battery is connected to the bus in the forward direction, the voltage values ​​corresponding to the AC side of the bridge circuit are all positive; when the battery is connected to the bus in the reverse direction, the voltage values ​​corresponding to the AC side of the bridge circuit are all negative; when the battery is in the forward bypass or reverse bypass, the voltage value corresponding to the AC side of the bridge circuit is zero.

[0062] Specifically, if the adjustable filter circuit is arranged on a single-phase bridge arm of the energy storage system, the first power transmission line refers to a power transmission line led out from an input / output interface of the single-phase bridge arm, and the input / output interface is used to connect an external electrical device or an external power supply device, and the second power transmission line refers to a power transmission line led out from the first power transmission line and used to connect a plurality of energy storage units connected in series.

[0063] An embodiment of the present application also provides an energy storage system, which includes a single-phase bridge arm, wherein the single-phase bridge arm includes: an input-output interface, which is used to connect an external electrical device or an external power supply device; a plurality of energy storage units, which are sequentially connected in series to a busbar of the single-phase bridge arm and are charged and discharged through the input-output interface; wherein an adjustable filter circuit as described in the first aspect or any possible implementation manner of the first aspect is arranged between the input-output interface and the busbar of the single-phase bridge arm, and / or at least one energy storage unit includes the adjustable filter circuit as described in the first aspect or any possible implementation manner of the first aspect.

[0064] For example, see Fig. 9 , Fig. 9 A schematic diagram of an energy storage system provided in an embodiment of the present application. Fig. 9 As shown, the single-phase bridge arm includes an input and output interface A io , the input-output interface is used to connect an external power-consuming device or an external power supply device; a plurality of energy storage units (A1 to An), the plurality of energy storage units are sequentially connected in series on the busbar of the single-phase bridge arm and are charged and discharged through the input-output interface; an adjustable filter circuit 100 is arranged between the input-output interface and the busbar of the single-phase bridge arm. Each energy storage unit may also include an adjustable filter circuit 100, and the adjustable filter circuit arranged between the input-output interface and the busbar of the single-phase bridge arm may be different from the adjustable filter circuit in each energy storage unit.

[0065] That is to say, if the energy storage system is a single-phase energy storage system, and only single-phase electricity is input and output, an adjustable filter circuit can be set between the input and output interface of the single-phase bridge arm and multiple energy storage units connected in series, and different filter sub-circuits can be selected through a multiple-selection switch to connect to the single-phase bridge arm to achieve different frequency filtering of the electric energy flowing out or in the single-phase bridge arm. In other words, an electric energy transmission line led out of the input and output interface is used as the first electric energy transmission line, and a second electric energy transmission line is led out from the first electric energy transmission line, and the second electric energy transmission line is also used to connect multiple energy storage units connected in series, or the second electric energy transmission line is used as the busbar of the single-phase bridge arm.

[0066] An embodiment of the present application also provides an energy storage system, which includes a three-phase bridge arm, wherein each single-phase bridge arm in the three-phase bridge arm includes: an input-output interface, wherein the input-output interface is used to connect an external electrical device or an external power supply device; a plurality of energy storage units, wherein the plurality of energy storage units are sequentially connected in series to a busbar of the single-phase bridge arm and are charged and discharged through the input-output interface; wherein an adjustable filter circuit as described in the aforementioned embodiment is arranged between the input-output interface of at least one single-phase bridge arm and the busbar of the single-phase bridge arm, and / or at least one energy storage unit corresponding to at least one single-phase bridge arm includes the adjustable filter circuit as described in the aforementioned embodiment.

[0067] At least one single-phase bridge arm in the three-phase bridge arm also includes a single-pole multi-throw switch and a control module, the single-pole multi-throw switch includes multiple branches, and for each branch, the branch is a clear branch or a connected protection circuit, wherein the control module is configured to: control the clear branch of the single-pole multi-throw switch to connect to the single-phase bridge arm or control the branch of the single-pole multi-throw switch connected to the protection circuit to connect to the single-phase bridge arm.

[0068] The adjustable filter circuit is arranged on the target single-phase bridge arm in the three-phase bridge arm, the target single-phase bridge arm comprises a control module, the first multiple-selection switch and / or the second multiple-selection switch in the adjustable filter circuit comprises at least one idle switching contact, wherein the control module is configured to: control the idle switching contact in the first multiple-selection switch or the second multiple-selection switch in the adjustable filter circuit to be empty or control the adjustable filter circuit to be connected to the target single-phase bridge arm.

[0069] That is to say, if the adjustable filter circuit arranged on the target single-phase bridge arm includes a first multiple-selection switch and / or a second multiple-selection switch, it is only necessary to have one switching contact in the first multiple-selection switch and / or the second multiple-selection switch as an idle switching contact, and no filtering sub-circuit is connected to the idle switching contact. When the idle switching contact of the multiple-selection switch is connected to the single-phase bridge arm, the power transmission of the single-phase bridge arm is cut off, and no power flows through the single-phase bridge arm.

[0070] For example, see Fig.10 , Fig.10 This is a schematic diagram of another energy storage system provided in an embodiment of the present application. Fig.10As shown, the energy storage system includes an A-phase bridge arm, a B-phase bridge arm, and a C-phase bridge arm. Among them, the energy storage units A1 to An of the A-phase bridge arm are connected in series in sequence, and the AC side of the bridge circuit of the energy storage unit A1 located in the first position is connected to the input and output interface Aio of the A-phase bridge arm through an adjustable filter circuit 100; the energy storage units B1 to Bn of the B-phase bridge arm are connected in series in sequence, and the AC side of the bridge circuit of the energy storage unit B1 located in the first position is connected to the input and output interface Bio of the B-phase bridge arm through an adjustable filter circuit 100; the energy storage units C1 to Cn of the C-phase bridge arm are connected in series in sequence, and the AC side of the bridge circuit of the energy storage unit C1 located in the first position is connected to the input and output interface Cio of the C-phase bridge arm through an adjustable filter circuit 100.

[0071] Among them, a single-pole multi-throw switch Ka is also provided on the A-phase bridge arm, and the single-pole multi-throw switch includes multiple branches, and for each branch, the branch is an empty branch or connected to a protection circuit. The single-pole multi-throw switch can be controlled by the control module to switch different branches to disconnect the single-phase bridge arm or release the excess electric energy on the single-phase bridge arm through the protection circuit. The control module is also used to determine whether there is a voltage or current abnormality in the single-phase electricity of each single-phase bridge arm. When determining that the single-phase electricity of the single-phase bridge arm is abnormal, the single-pole multi-throw switch of the single-phase bridge arm is first controlled to be empty to prevent damage to the components of other single-phase bridge arms, that is, the empty branch of the single-pole multi-throw switch is controlled to be connected to the single-phase bridge arm, and then the branch connected to the protection circuit in the single-pole multi-throw switch of the single-phase bridge arm is connected to the single-phase bridge arm, that is, the branch connected to the protection circuit of the single-pole multi-throw switch is controlled to be connected to the single-phase bridge arm, so as to consume the excess electric energy on the single-phase bridge arm through the protection circuit. Furthermore, the control module can control the multi-select switch K1 to select a suitable filtering sub-circuit to connect to the single-phase bridge arm according to the filtering frequency required by the A-phase bridge arm, and can also control the single-pole multi-throw switch Ka to select whether to turn on the single-phase bridge arm, and whether to connect the protection circuit to consume the electrical energy on the single-phase bridge arm after the single-phase bridge arm is disconnected.

[0072] Among them, the control module is also used to collect information such as voltage, current, temperature, etc. of each energy storage unit, and determine whether each energy storage unit has an abnormality. If it is determined that the voltage, current or temperature of any energy storage unit under the single-phase bridge arm is abnormal, the single-phase bridge arm where the abnormal energy storage unit is located is controlled to be disconnected, that is, the empty branch of the single-pole multi-throw switch of the single-phase bridge arm where the abnormal energy storage unit is located is controlled to be connected to the single-phase bridge arm.

[0073] Among them, Fig.10As shown, the multiple-selection switch of the adjustable protection circuit in the B-phase bridge arm includes an idle switching contact. Then, when the control module determines that the single-phase bridge arm needs to be disconnected, the control module controls the idle switching contact of the multiple-selection switch in the adjustable filter circuit to be empty, thereby cutting off the power transmission in the single-phase bridge arm, thereby protecting various components. Alternatively, the control module can connect the adjustable filter circuit to the target single-phase bridge arm when it is determined that there is power transmission in the single-phase bridge arm, that is, select the switching contact corresponding to the filter sub-circuit that meets the required filtering frequency range to connect to the single-phase bridge arm, so as to filter the power flowing through the single-phase bridge arm.

[0074] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0075] It should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0076] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An adjustable filter circuit, characterized in that: The adjustable filter circuit is arranged on the energy storage unit and / or arranged on the single-phase bridge arm of the energy storage system. The adjustable filter circuit includes a first multiple-selection switch and a plurality of first filter subcircuits, wherein the plurality of first filter subcircuits correspond to different filter frequency ranges. The first multiple-selection switch includes a plurality of first switching contacts, and one first switching contact of the first multiple-selection switch is correspondingly connected to one first filtering sub-circuit.

2. The adjustable filter circuit according to claim 1, characterized in that: The adjustable filter circuit further includes a second filter subcircuit or a plurality of second filter subcircuits, wherein the plurality of second filter subcircuits correspond to different filter frequency ranges, a first target filter subcircuit in the first filter subcircuit and the second filter subcircuit includes a resistor, and a second target filter subcircuit in the first filter subcircuit and the second filter subcircuit includes a capacitor, The first target filter subcircuit is arranged on a first power transmission line, and the second target filter subcircuit is arranged on a second power transmission line derived from the first power transmission line.

3. The adjustable filter circuit according to claim 2, characterized in that: The adjustable filter circuit also includes a second multiple-selection switch connected to a plurality of second filter sub-circuits, the second multiple-selection switch includes a plurality of second switching contacts, and one second switching contact of the second multiple-selection switch is correspondingly connected to one second filter sub-circuit.

4. The adjustable filter circuit according to claim 1, characterized in that: Each first filtering subcircuit comprises a resistor and a capacitor, For each first filtering subcircuit, a resistor of the first filtering subcircuit is arranged on a first power transmission line, a second power transmission line is led out from one end of the resistor, and a capacitor of the first filtering subcircuit is arranged on the second power transmission line. Each first switching contact of the first multiple-selection switch is correspondingly connected to a resistor or a capacitor of the first filtering subcircuit.

5. The adjustable filter circuit according to any one of claims 2 to 4, characterized in that: The energy storage unit includes a battery and a bridge circuit, and the adjustable filter circuit is arranged between the battery and the bridge circuit. The first power transmission line refers to a first preset power transmission line between the positive electrode of the battery and one end of the DC side of the bridge circuit or a second preset power transmission line between the negative electrode of the battery and the other end of the DC side of the bridge circuit. The second power transmission line is arranged between the first preset power transmission line and the second preset power transmission line.

6. The adjustable filter circuit according to any one of claims 2 to 4, characterized in that: The adjustable filter circuit is arranged on the single-phase bridge arm of the energy storage system, the first power transmission line refers to a power transmission line led out from the input and output interface of the single-phase bridge arm, the input and output interface is used to connect an external electrical device or an external power supply device, and the second power transmission line refers to a power transmission line led out from the first power transmission line and used to connect multiple energy storage units connected in series.

7. An energy storage unit, characterized in that: The energy storage unit comprises: Battery; A bridge circuit, wherein the AC side of the bridge circuit is used to connect to the busbar of the single-phase bridge arm of the energy storage system; The adjustable filter circuit according to any one of claims 1 to 6, wherein the adjustable filter circuit is arranged between the battery and the DC side of the bridge circuit.

8. The energy storage unit according to claim 7, characterized in that: The bridge circuit includes a first control switch, a second control switch, a third control switch and a fourth control switch, Among them, one end of the first control switch is connected to one end of the second control switch, the other end of the first control switch is connected to one end of the third control switch, the other end of the second control switch is connected to one end of the fourth control switch, and the other end of the third control switch is connected to the other end of the fourth control switch.

9. The energy storage unit according to claim 8, characterized in that: The connection between the first control switch and the second control switch serves as one end of the DC side of the bridge circuit, and the connection between the third control switch and the fourth control switch serves as the other end of the DC side of the bridge circuit. The connection between the first control switch and the third control switch and the connection between the second control switch and the fourth control switch serve as the AC side of the bridge circuit.

10. An energy storage system, characterized in that: The energy storage system comprises a single-phase bridge arm, wherein the single-phase bridge arm comprises: Input / output interface, the input / output interface is used to connect to external electrical equipment or external power supply equipment; A plurality of energy storage units, wherein the plurality of energy storage units are sequentially connected in series to the busbar of the single-phase bridge arm and are charged and discharged through the input and output interface; Wherein, an adjustable filter circuit as described in any one of claims 1 to 6 is arranged between the input-output interface and the busbar of the single-phase bridge arm, and / or at least one energy storage unit includes the adjustable filter circuit as described in any one of claims 1 to 6.

11. An energy storage system, characterized in that: The energy storage system comprises a three-phase bridge arm, wherein each single-phase bridge arm in the three-phase bridge arm comprises: Input / output interface, the input / output interface is used to connect to external electrical equipment or external power supply equipment; A plurality of energy storage units, wherein the plurality of energy storage units are sequentially connected in series to the busbar of the single-phase bridge arm and are charged and discharged through the input and output interface; Among them, an adjustable filter circuit as described in any one of claims 1 to 6 is arranged between the input-output interface of at least one single-phase bridge arm and the busbar of the single-phase bridge arm, and / or at least one energy storage unit corresponding to at least one single-phase bridge arm includes the adjustable filter circuit as described in any one of claims 1 to 6.

12. The energy storage system according to claim 11, characterized in that: At least one single-phase bridge arm in the three-phase bridge arm further includes a single-pole multi-throw switch and a control module, wherein the single-pole multi-throw switch includes a plurality of branches, and for each branch, the branch is a blank branch or connected to a protection circuit, Wherein, the control module is configured to: control the empty branch of the single-pole multi-throw switch to be connected to the single-phase bridge arm or control the branch of the single-pole multi-throw switch connected to the protection circuit to be connected to the single-phase bridge arm.

13. The energy storage system according to claim 11, characterized in that: The adjustable filter circuit is arranged on the target single-phase bridge arm in the three-phase bridge arm, the target single-phase bridge arm comprises a control module, the first multiple-selection switch and / or the second multiple-selection switch in the adjustable filter circuit comprises at least one idle switching contact, The control module is configured to: control the idle switching contacts in the first multiple-selection switch or the second multiple-selection switch in the adjustable filter circuit to be empty or control the adjustable filter circuit to be connected to the target single-phase bridge arm.

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