Inverter, rectifier, frequency converter and photovoltaic power generation system

Abstract

The invention provides an inverter, a rectifier, a frequency converter and a photovoltaic power generation system.The inverter comprises a first power board, a second power board and a first filter, the first power board comprises a first input end, a second input end, an inverter circuit, a first filter circuit and an output end, the inverter circuit is used for converting direct current into alternating current, and the first filter circuit is used for filtering the alternating current; the first filter comprises an input end, a second filter circuit, a first output end and a second output end, the input end of the first filter is connected with the output end of the first power board, and the impedance of the first output end of the first filter is smaller than that of the second output end of the first filter; the second input end of the first power board is connected with the first output end of the first filter, the first filter circuit is connected with the second input end of the first power board, the input end of the second power board is connected with the second output end of the first filter, and the output end is used for being connected with an alternating-current power grid or a load. Therefore, the inverter provided by the invention can improve the filtering effect and save the cost.

Description

[0001] This application claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on September 27, 2023, with application number 202311277873.2, and priority to the Chinese patent application with the invention name “An inverter, rectifier, converter and photovoltaic power generation system”, all contents of which are incorporated by reference in this application. Technical Field

[0002] The present application relates to the field of electric power technology, and in particular to an inverter, a rectifier, a frequency converter and a photovoltaic power generation system. Background Art

[0003] An inverter (INV) is a device that converts direct current (DC) into alternating current (AC). For high-power inverters, in order to increase the power density of the entire machine, a two-layer architecture is usually adopted (one layer is mainly for power conversion function, and the other layer is mainly for power output and sampling control). The AC filter layout of traditional inverters usually has a long filter loop, which will lead to poor filtering effect and high cost; or in order to shorten the filter loop, a more complex wiring method is adopted, which is difficult to design and has a high cost. Therefore, how to make high-power inverters take into account both filtering effect and cost is a problem that needs to be solved urgently. Summary of the invention

[0004] The present application provides an inverter, a rectifier, a frequency converter and a photovoltaic power generation system, which can improve filtering effects and save material costs.

[0005] In the first aspect, an inverter is provided, comprising a first power board, a second power board, an inverter circuit, a first filter circuit, a second filter circuit and a third filter circuit. The first power board is used to fix the inverter circuit and the first filter circuit, and the first filter circuit is electrically connected to the DC input terminal of the inverter circuit through the first power board. The second filter circuit comprises one or more inverter inductors, and the output terminal of the inverter inductor is electrically connected to the input terminal of the first filter circuit through the first wire and the first power board in turn. The second power board is used to fix the third filter circuit, and the third filter circuit is electrically connected to the output terminal of the inverter inductor through the second power board and the second wire, and the third filter circuit is used to be electrically connected to a power grid or a load. The inverter circuit is used to convert direct current into alternating current and transmit the alternating current to the inverter inductor, and the inverter inductor is used to filter the alternating current and transmit a part of the filtered alternating current to the first filter circuit through the first wire, and transmit another part of the filtered alternating current to the third filter circuit through the second wire. Among them, the impedance of the electrical connection line between the output end of the inverter inductor and the output end of the first filter circuit to the high-frequency ripple current is less than the impedance of the electrical connection line between the output end of the inverter inductor and the output end of the third filter circuit to the high-frequency ripple current, and the frequency of the high-frequency ripple current is greater than the power frequency. Such a setting can automatically separate the high-frequency ripple current and the power frequency current from the alternating current after filtering by the inverter inductor, thereby ensuring the quality of the output current of the inverter. At the same time, since the high-frequency ripple current flows directly to the first filter circuit through the first wire, the filtering loop of the high-frequency ripple can be shortened, and the electromagnetic compatibility of the inverter can be improved. Furthermore, since the power frequency current flows directly to the third filter circuit through the second wire, the design of the first power board can be simplified, the wiring of the inverter inductor and the third filter circuit can be simplified, the wiring space of the inverter can be reduced, and the power density of the inverter can be improved.

[0006] In a possible implementation, the diameter of the first wire is smaller than the diameter of the second wire. Since the power frequency current is much larger than the high frequency ripple current, such a configuration can reduce the heat generated by the second wire and improve the power conversion efficiency of the inverter.

[0007] In a possible implementation manner, the inverter inductor includes a coil, a magnetic core, and a packaging body. The coil is wound around the magnetic core, and the coil and the magnetic core are arranged in the packaging body.

[0008] In a possible implementation, the first filtering circuit includes a capacitor.

[0009] In a possible implementation, the third filtering circuit includes a differential mode inductor, and the differential mode inductor is used to filter the differential mode signal in another part of the alternating current filtered by the inverter inductor.

[0010] In a possible implementation, the third filtering circuit includes a common-mode inductor, and the common-mode inductor is used to filter the common-mode signal in another part of the alternating current filtered by the inverter inductor.

[0011] In the second aspect, an inverter is provided, comprising a first power board, a second power board, an inverter circuit, a first filter circuit, a second filter circuit and a third filter circuit. The first power board is used to fix the inverter circuit and the first filter circuit, and the first filter circuit is electrically connected to the DC input terminal of the inverter circuit through the first power board. The second filter circuit comprises one or more inverter inductors, and the first output terminal of the inverter inductor is electrically connected to the input terminal of the first filter circuit through a first wire. The second power board is used to fix the third filter circuit, and the third filter circuit is electrically connected to the second output terminal of the inverter inductor through the second power board and the second wire in sequence, and the third filter circuit is used to be electrically connected to a power grid or a load. The inverter circuit is used to convert direct current into alternating current and transmit the alternating current to the inverter inductor, and the inverter inductor is used to filter the alternating current and transmit a part of the filtered alternating current to the first filter circuit through the first wire, and transmit another part of the filtered alternating current to the third filter circuit through the second wire. Among them, the impedance of the electrical connection line between the first output end of the inverter inductor and the output end of the first filter circuit to the high-frequency ripple current is less than the impedance of the electrical connection line between the second output end of the inverter inductor and the output end of the third filter circuit to the high-frequency ripple current, and the frequency of the high-frequency ripple current is greater than the power frequency. Such a setting can automatically separate the high-frequency ripple current and the power frequency current from the alternating current after filtering by the inverter inductor, thereby ensuring the quality of the output current of the inverter. At the same time, since the high-frequency ripple current flows directly to the first filter circuit through the first wire, the filtering loop of the high-frequency ripple can be shortened, and the electromagnetic compatibility of the inverter can be improved. Furthermore, since the power frequency current flows directly to the third filter circuit through the second wire, the design of the first power board can be simplified, the wiring of the inverter inductor and the third filter circuit can be simplified, the wiring space of the inverter can be reduced, and the power density of the inverter can be improved.

[0012] For other possible implementations of the second aspect, reference may be made to the implementations of the first aspect described above, and details will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of a power generation system provided in an embodiment of the present application.

[0014] Figure 2 A schematic diagram of an inverter provided in an embodiment of the present application.

[0015] Figure 3 A schematic diagram of an inverter provided in an embodiment of the present application.

[0016] Figure 4A schematic diagram of an inverter provided in an embodiment of the present application.

[0017] Figure 5 is a schematic diagram of current applicable to the embodiments of the present application.

[0018] Figure 6 is a schematic diagram of an inductor suitable for an embodiment of the present application.

[0019] Figure 7 It is a structural schematic diagram of the first power board, the second power board and the first filter provided in an embodiment of the present application.

[0020] Figure 8 It is a schematic diagram of a power generation system provided in an embodiment of the present application.

[0021] Fig. 9 It is a schematic diagram of a power generation system provided in an embodiment of the present application.

[0022] Reference numerals:

[0023] 100-inverter; 200-first power board; 300-second power board; 400-first filter; 210-inverter circuit; 220-first filter circuit; 21-first input terminal of the first power board; 22-second input terminal of the first power board; 23-output terminal of the first power board; 31-input terminal of the second power board; 32-output terminal of the second power board; 41-input terminal of the first filter; 42-first output terminal of the first filter; 43-second output terminal of the first filter; 410-second filter circuit; 411-inverter inductor; 4111-coil; 4112-magnetic core; 4113-package. DETAILED DESCRIPTION

[0024] The following explains the terms that may appear in the embodiments of the present application.

[0025] Double-layer structure inverter: It is a power converter used to convert direct current into alternating current. It mainly adopts a double-layer power board design, and the control circuit and power circuit of the inverter are placed separately on two different power boards. The control circuit is located on the second power board and is responsible for controlling the working state and output voltage and other parameters of the inverter; among them, the control circuit usually includes a microprocessor or a digital signal processor, which is used to process input signals, monitor output voltage and current, and calculate control algorithms. In addition, the control circuit also includes a protection circuit, which is used to monitor the operating state of the inverter and take protective measures in time when a fault or abnormal situation occurs. The inverter circuit is located on the first power board. When the control circuit issues an instruction, the inverter circuit will control the switching state of the switching device according to the instruction to convert the electrical energy of the DC power supply into AC power.

[0026] Inverter inductor: It is a commonly used component in inverter circuits, used to filter and stabilize the output voltage. It suppresses the change of current through its own self-inductance, thereby reducing the fluctuation and harmonic content of the output voltage. When the switching device of the inverter is switched, a pulse current of the switching frequency will be generated. These pulse currents will pass through the inverter inductor. Due to the self-inductance, the inverter inductor will resist the change of current, making the output current change more stable and reducing the harmonic components of the current; at the same time, the inverter inductor can also store energy. When the switching device is turned off, the inverter inductor will release the stored energy to maintain the continuity of the output current, thereby stabilizing the output voltage; in addition, it can also suppress electromagnetic interference and reduce electromagnetic radiation.

[0027] The first filter circuit is a commonly used circuit in the inverter, which is used to further smooth the output current and reduce the current ripple. The capacitor of the first filter circuit can store charge and provide electrical energy between the positive and negative half cycles of the current, thereby reducing the current ripple. The resistor of the first filter circuit mainly plays the role of consuming current, making the output current more stable.

[0028] The midpoint of the input terminal of the inverter circuit: refers to the middle connection point between the two polarities of the inverter input power supply. Usually, the input power supply of the inverter is a DC power supply, and this midpoint is the connection point between the positive and negative poles of the DC power supply. The midpoint of the input terminal of the inverter circuit plays a role in balancing and stabilizing the current in the inverter, and also helps to reduce current shocks and voltage fluctuations, and improve the stability and performance of the inverter. When using the inverter in an AC power grid, the midpoint of the input terminal can also be connected to the ground (ground wire) to provide better electrical safety and electromagnetic compatibility.

[0029] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0030] Figure 1 The schematic diagram of a photovoltaic power generation system includes: photovoltaic modules, an AC power grid, and an inverter. The output ports of M photovoltaic modules are connected to the input end of the inverter, and the output end of the inverter is connected to the input end of the AC power grid. The photovoltaic modules are used to generate direct current, and the inverter is used to invert the direct current and input the AC power obtained by the inversion process into the AC power grid. The AC power grid is used to provide AC power to the outside.

[0031] It should be noted that the above-mentioned photovoltaic components refer to devices that use the photovoltaic effect of semiconductor materials under lighting conditions to directly convert solar energy into electrical energy. Photovoltaic components can also be called photovoltaic arrays, solar panels, etc.

[0032] The inverter in the photovoltaic power generation system is usually divided into a single-layer structure and a double-layer structure. In the double-layer structure inverter, the wiring layout of the first filter circuit can be divided into two types. The first wiring layout is that the first filter circuit follows the second power board, such as Figure 2 As shown, the output end of the first power board is electrically connected to the input end of the filter, the output end of the filter is directly electrically connected to the input end of the second power board, direct current is input from the first input end of the first power board to the inverter circuit, after the direct current is converted into alternating current, it is output from the output end of the first power board to the input end of the filter, alternating current is input from the input end of the second power board to the first filter circuit, after being filtered by the first filter circuit, the ripple current is filtered and then the alternating current is output, and the alternating current is output from the output end of the second power board to the alternating current grid or load. In the wiring layout of the above-mentioned first filter circuit, the ripple current will have the problem of a long filtering path, which affects the filtering effect. In addition, for the electrical safety and electromagnetic compatibility of the circuit, the output end of the first filter circuit is electrically connected to the midpoint of the input end of the inverter circuit, and the path between the two is also long, which is not conducive to cost saving.

[0033] The second wiring layout is that the first filter circuit follows the first power board, such as Figure 3 As shown, the output end of the filter inputs the AC power processed by the inverter inductor to the second input end of the first power board. After the AC power passes through the first filter circuit to filter the ripple current, a certain wiring space is required on the first power board to connect the output end of the filter and the output end of the first power board so that the AC power is output from the output end of the first power board to the input end of the second power board. In the wiring layout of the above-mentioned first filter circuit, the AC power needs to be transferred from the first power board to the second power board, which requires a larger wiring space on the first power board, and the design difficulty and cost also increase accordingly.

[0034] Therefore, the embodiment of the present application provides an inverter, which can make the wiring layout of the first filter circuit more reasonable, improve the filtering effect, and save material costs.

[0035] The embodiment of the present application provides an inverter 100, Figure 4 It is a schematic diagram of an inverter 100, which includes a first power board 200, a second power board 300 and a first filter 400. The first power board 200 and the second power board 300 can be stacked, with the second power board 300 located above the first power board 200, or the first power board 200 and the second power board 300 are placed horizontally, and the first filter 400 is placed independently of the first power board 200 and the second power board 300.

[0036] Specifically, the first power board 200 includes a first input terminal 21, a second input terminal 22 and an output terminal 23, which are used to fix the inverter circuit 210 and the first filter circuit 220. The first input terminal 21 of the first power board 200 is used to input direct current from a DC system or a rectifier or other equipment, the inverter circuit 210 is used to convert direct current into alternating current, the output terminal 23 of the first power board is used to output alternating current, the first filter 400 includes an input terminal 41, a second filter circuit 410, a first output terminal 42 and a second output terminal 43, wherein the first output terminal 42 and the second output terminal 43 are collectively referred to as the output terminals of the inverter inductor 411, and the second filter circuit 410 may include one or more inverter inductors 411 connected in series, and one inverter inductor 411 is used as an example in the following description.

[0037] The input terminal 41 of the first filter 400 is electrically connected to the output terminal 23 of the first power board 200. The alternating current is input from the input terminal 41 of the first filter 400 to the inverter inductor 411. The inverter inductor 411 is used to filter the alternating current output by the inverter circuit 210. A part of the alternating current processed by the inverter inductor 411 is output from the first output terminal 42, and another part of the alternating current processed by the inverter inductor 411 is output from the second output terminal 43.

[0038] It should be noted that if Figure 5 As shown, after being processed by the inverter inductor 411, on the coordinate axis of time T and current I, a high-frequency ripple current (Ripple Current) is superimposed on the power frequency current and outputted. The high-frequency ripple current is a current fluctuation or ripple caused by an alternating current or a periodically changing voltage source in a circuit, which can easily cause electronic components to absorb and release energy periodically, thereby causing components to heat up, increase energy consumption, and possibly shorten the life of components, generate electromagnetic interference, and also affect the performance of other electronic equipment or circuits. In some cases, the ripple current may cause oscillation problems in the circuit, leading to unstable working conditions and affecting the performance and reliability of the system. Among them, the frequency of the high-frequency ripple current is greater than the frequency of the power frequency current.

[0039] In order to make the inverter 100 output a stable power frequency current, it is necessary to remove the high frequency ripple current of the alternating current output by the inverter inductor 411. Figure 4The inverter inductor 411 is electrically connected to the first power board 200 through the first wire 51, so that a part of the AC power filtered by the inverter inductor 411 is transmitted to the first power board 200 through the first wire 51, and the first power board 200 continues to transmit a part of the AC power filtered by the inverter inductor 411 to the first filter circuit 220 through the internal wiring. Further, the inverter inductor 411 is electrically connected to the second power board 300 for carrying the third filter circuit 310 through the second wire 52, so that another part of the AC power filtered by the inverter inductor 411 is transmitted to the second power board 300 through the second wire 52, and the second power board 300 continues to transmit another part of the AC power filtered by the inverter inductor 411 to the third filter circuit 310 through the internal wiring, and the third filter circuit 310 is used to connect to the power grid or load. The impedance of the electrical connection line between the output end of the inverter inductor 411 and the output end of the first filter circuit 220 to the high-frequency ripple current is smaller than the impedance of the electrical connection line between the output end of the inverter inductor 411 and the output end of the third filter circuit 310 to the high-frequency ripple current.

[0040] Specifically, the high-frequency ripple current is output from the first output terminal 42 to the first input terminal 22 of the first power board 200, the input terminal of the first filter circuit 220 is electrically connected to the first input terminal 22 of the first power board, the output terminal of the first filter circuit 220 is connected to the midpoint of the input terminal of the inverter circuit, and the high-frequency ripple current is filtered and processed by the first filter circuit 220. The second power board 300 includes an input terminal 31, a third filter circuit 310 and an output terminal 32, the third filter circuit 310 is connected in series between the input terminal 31 of the second power board 300 and the output terminal 32 of the second power board 300, and the alternating current is output from the second output terminal 43 of the first filter 400 to the input terminal 31 of the second power board, filtered by the third filter circuit 310, and then output from the output terminal 32 of the second power board to the alternating current grid or load.

[0041] With such a configuration, the AC power after filtering by the inverter inductor 411 can be automatically separated into high-frequency ripple current and power frequency current, thereby ensuring the quality of the output current of the inverter 100. At the same time, since the high-frequency ripple current flows directly to the first filter circuit 220 through the first wire 51, the filter loop of the high-frequency ripple can be shortened, thereby improving the electromagnetic compatibility of the inverter 100. Furthermore, since the power frequency current flows directly to the third filter circuit 310 through the second wire 52, the design of the first power board 200 can be simplified, the wiring between the inverter inductor 411 and the third filter circuit 310 can be simplified, the wiring space of the inverter 100 can be reduced, and the power density of the inverter 100 can be improved.

[0042] It should be noted that, in practical applications, the first output terminal 42 and the second output terminal 43 here can be two independent terminals or combined into one terminal. When the first output terminal 42 and the second output terminal 43 are two independent terminals, the first output terminal 42 is electrically connected to the first power board 200 through the first wire 51, and the wiring inside the first power board 200 further electrically connects the first output terminal 42 to the first filter circuit 220, and the second output terminal 43 is electrically connected to the second power board 300 through the second wire 52, and the wiring inside the second power board 300 further electrically connects the second output terminal 43 to the third filter circuit 310. When the first output terminal 42 and the second output terminal 43 are combined into one terminal, the first wire 51 and the second wire 52 are wrapped by insulation to form a wire, one end of the wire is connected to the terminal combined by the first output terminal 42 and the second output terminal 43, and there is a gap in the insulation of the middle part of the wire, which is used to lead out the first wire 51, thereby electrically connecting the first wire 51 to the first power board 200 and the second wire 52 to the second power board 300.

[0043] For an implementation in which the first output terminal 42 and the second output terminal 43 are two independent terminals, see Figure 6 .like Figure 6 As shown, the inverter inductor 411 includes a coil 4111, a magnetic core 4112 and a package 4113. The coil 4111 is wound around the magnetic core 4112, and the coil 4111 and the magnetic core 4112 are arranged in the package 4113. The end of the coil 4111 is divided into two independent terminals, namely a first output terminal 42 and a second output terminal 43, wherein the first output terminal 42 is used to be electrically connected to the first power board 200 through a first wire 51, and the second output terminal 43 is used to be electrically connected to the second power board 300 through a second wire 52. It is worth mentioning that for the convenience of display, Figure 6 The housing of the first filter is hidden. In practical applications, a housing for accommodating the inverter inductor 411 can be provided to ensure the structural stability of the inverter inductor 411. The first filter 400 further includes a third wire (not shown). The inverter inductor 411 is connected to the input terminal 41 of the first filter 400 through the third wire. The third wire can be led out from the coil 4111 of the inverter inductor 411, or the third wire is connected to the wire of the coil.

[0044] See also Figure 7 , Figure 7Schematic diagram of the structure of the first power board 200, the second power board 300 and the first filter 400. In this embodiment, the first output terminal 42 and the second output terminal 43 are combined into a terminal, and the first wire 51 and the second wire 52 are wrapped by an insulating skin to form a wire. In the middle of the wire, the first wire 51 extends out from the gap of the insulating skin, so that the first wire 51 is electrically connected to the first power board 200. Among them, the diameter of the first wire 51 is smaller than the diameter of the second wire 52. As mentioned above, since the power frequency current is much larger than the high-frequency ripple current, such a setting can reduce the heat generated by the second wire 52 and improve the power conversion efficiency of the inverter 100.

[0045] Furthermore, the first filter 400 includes a housing 420 and a second filter circuit 410, and the second filter circuit 410 includes three inverter inductors 411. It is worth mentioning that in practical applications, the number of the inverter inductors 411 can be set as required and is not limited to three.

[0046] Optionally, the first output terminal 42 and the second output terminal 43 can be amplified and processed by superimposing a switching circuit such as a multiplexer, or using an amplifier and other related circuits to amplify and process the selected output current to improve the decoupling effect of the ripple current and the power current, which is not specifically limited in the embodiments of the present application.

[0047] The inverter provided in the embodiment of the present application connects the first filter 400 to two output lines with different impedances to high-frequency ripple current, thereby changing the direction of the ripple current in the alternating current, so that the high-frequency ripple current is decoupled from the alternating current at the first output terminal 42 and the second output terminal 43 of the first filter 400, thereby improving the filtering effect. At the same time, it avoids the high-frequency ripple current from being filtered after following the alternating current input to the second power board 300, effectively shortening the filtering path of the ripple current and reducing the instability in the alternating current earlier. In addition, it also avoids the high-frequency ripple current from being input to the first power board 200 following the alternating current, and the alternating current filtered by the first filter circuit 220 is then output from the first power board 200 to the second power board 300, thereby reducing the wiring space of the first power board 200 and also helping to save costs.

[0048] In some embodiments, the inverter circuit 210 includes a drive control circuit, a DC conversion circuit, a drive circuit, a protection detection circuit, a resonant capacitor, an output current sampling circuit, etc., wherein the drive control circuit may include an oscillator and a modulator, and the drive circuit may include a power output tube and a high-voltage transformer, which is not specifically limited in the embodiments of the present application.

[0049] In some embodiments, the first filter circuit includes a capacitor, and the high-frequency ripple current is input into the capacitor of the first filter circuit 220 and filtered by the capacitor. The first filter circuit 220 may also include a bipolar transistor, a unipolar transistor, an integrated operational amplifier, and the like.

[0050] In some embodiments, the third filter circuit 310 includes a differential mode inductor, which is used to filter the differential mode signal in the alternating current, the input end of the differential mode inductor is electrically connected to the input end 31 of the second power board, the output end of the differential mode inductor is electrically connected to the output end 32 of the second power board, the alternating current is input to the differential mode inductor from the input end 31 of the second power board, the differential mode signal is further filtered, and the filtered alternating current is output to the output end 32 of the second power board. In other embodiments, the third filter circuit 310 includes a common mode inductor, which is used to filter the common mode signal in the alternating current, the input end of the common mode inductor is electrically connected to the input end 31 of the second power board, the output end of the common mode inductor is electrically connected to the input end of the differential mode inductor, and the output end of the differential mode inductor is electrically connected to the output end 32 of the second power board, further filtering the common mode signal and the differential mode signal in the alternating current. In the embodiment of the present application, by setting the differential mode inductor or the common mode inductor, the stability of the alternating current is further improved.

[0051] In some embodiments, the inverter 100 further includes a first switch, the output end of the first switch is connected to the output end of the inverter circuit 210, the output end of the first switch is connected to the output end 23 of the first power board, and the first switch is used to control the disconnection or conduction of the AC power output by the inverter circuit 210. By setting the first switch, the signals or power supplies between different circuits can be effectively isolated to prevent the problem of one circuit from affecting another circuit, which is conducive to improving the stability and safety of the inverter circuit.

[0052] The present application also provides a wind power generation system, such as Figure 8 As shown, the inverter of the embodiment of the present application can be applied to the wind power generation system, which includes a wind turbine, a rectifier and an inverter. The inverter is used to convert the direct current from the wind turbine into alternating current and transmit it to the power grid.

[0053] The present application also provides an energy storage grid-connected power generation system, such as Fig. 9 As shown, the inverter of the embodiment of the present application can be applied to the energy storage grid-connected power generation system, which is composed of an energy storage system, an inverter and an AC power grid. In the energy storage grid-connected power generation system, the inverter converts the DC power output by the energy storage system into AC power, and transmits the converted AC power to the AC power grid.

[0054] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An inverter, characterized in that: It includes a first power board, a second power board, an inverter circuit, a first filter circuit, a second filter circuit and a third filter circuit; wherein, The first power board is used to fix the inverter circuit and the first filter circuit, and the first filter circuit is electrically connected to the DC input terminal of the inverter circuit through the first power board; The second filter circuit includes one or more inverter inductors, and the output end of the inverter inductor is electrically connected to the input end of the first filter circuit through the first wire and the first power board in sequence; The second power board is used to fix the third filter circuit, the third filter circuit is electrically connected to the output end of the inverter inductor through the second power board and the second wire in sequence, and the third filter circuit is also used to be electrically connected to a power grid or a load; The inverter circuit is used to convert direct current into alternating current and transmit the alternating current to the inverter inductor, and the inverter inductor is used to filter the alternating current and transmit a part of the filtered alternating current to the first filter circuit through the first wire, and transmit another part of the filtered alternating current to the third filter circuit through the second wire; wherein, The impedance of the electrical connection line between the output end of the inverter inductor and the output end of the first filter circuit to the high-frequency ripple current is smaller than the impedance of the electrical connection line between the output end of the inverter inductor and the output end of the third filter circuit to the high-frequency ripple current, and the frequency of the high-frequency ripple current is greater than the industrial frequency.

2. The inverter according to claim 1, characterized in that: The diameter of the first conductive line is smaller than the diameter of the second conductive line.

3. The inverter according to claim 1, characterized in that: The inverter inductor comprises a coil, a magnetic core and a packaging body. The coil is wound around the magnetic core, and the coil and the magnetic core are arranged in the packaging body.

4. The inverter according to claim 1, characterized in that: The first filtering circuit includes a capacitor.

5. The inverter according to any one of claims 1 to 4, characterized in that: The third filtering circuit includes a differential mode inductor, and the differential mode inductor is used to filter the differential mode signal in another part of the alternating current filtered by the inverter inductor.

6. The inverter according to any one of claims 1 to 4, characterized in that: The third filtering circuit includes a common-mode inductor, and the common-mode inductor is used to filter the common-mode signal in another part of the alternating current filtered by the inverter inductor.

7. An inverter, characterized in that: It includes a first power board, a second power board inverter circuit, a first filter circuit, a second filter circuit and a third filter circuit; The first power board includes an inverter circuit and a first filter circuit, and the first filter circuit is electrically connected to a DC input terminal of the inverter circuit through the first power board; The second filter circuit includes one or more inverter inductors, and the first output end of the inverter inductor is electrically connected to the input end of the first filter circuit through the first wire and the first power board in sequence; The second power board is used to fix the third filter circuit, the third filter circuit is electrically connected to the second output end of the inverter inductor through the second power board and the second wire, and the third filter circuit is also used to electrically connect to a power grid or a load; The inverter circuit is used to convert direct current into alternating current and transmit the alternating current to the inverter inductor, and the inverter inductor is used to filter the alternating current and transmit a part of the filtered alternating current to the first filter circuit through the first wire, and transmit another part of the filtered alternating current to the third filter circuit through the second wire; wherein, The impedance of the electrical connection line between the first output end of the inverter inductor and the output end of the first filter circuit to the high-frequency ripple current is smaller than the impedance of the electrical connection line between the second output end of the inverter inductor and the output end of the third filter circuit to the high-frequency ripple current, and the frequency of the high-frequency ripple current is greater than the industrial frequency.

8. The inverter according to claim 7, characterized in that: The diameter of the first conductive line is smaller than the diameter of the second conductive line.

9. The inverter according to claim 7, characterized in that: The inverter inductor comprises a coil, a magnetic core and a packaging body. The coil is wound around the magnetic core, and the coil and the magnetic core are arranged in the packaging body.

10. The inverter according to claim 7, characterized in that: The first filtering circuit includes a capacitor.

11. The inverter according to any one of claims 7 to 10, characterized in that: The third filtering circuit includes a differential mode inductor, and the differential mode inductor is used to filter the differential mode signal in another part of the alternating current filtered by the inverter inductor.

12. The inverter according to any one of claims 7 to 10, characterized in that: The third filtering circuit includes a common-mode inductor, and the common-mode inductor is used to filter the common-mode signal in another part of the alternating current filtered by the inverter inductor.

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