Power supply voltage adjusting device based on inverter circuit

Abstract

The embodiment of the utility model provides a power supply voltage regulating device based on an inverter circuit, which comprises an input circuit, a voltage regulating circuit, an inverter circuit and a follow current circuit, and is characterized in that the input circuit filters input alternating current and outputs the alternating current through the output end of the input circuit; the voltage regulating circuit regulates input alternating current by modulating the working states of switching devices in the first switching device group and the second switching device group, and the output end of the voltage regulating circuit outputs voltage and serves as the output end of the power supply voltage regulating device based on the inverter circuit to supply power to a load; the inverter circuit is configured to adjust reactive current and harmonic current of the input alternating current or the output end of the power supply voltage adjusting device; the freewheeling circuit is configured to enable the voltage regulating circuit and the inverter circuit to form a freewheeling path to absorb overvoltage and peak voltage generated by the voltage regulating circuit. The embodiment of the utility model is simple in structure, effectively guarantees the stability of the power grid voltage, and has the advantages of quick response, low cost, simple and convenient control, high reliability and the like.

Description

Technical Field

[0001] This application relates to the fields of power generation, power transformation or power distribution technology, and specifically to a power supply voltage regulation device based on an inverter circuit. Background Technology

[0002] With continuous economic development, electricity consumption has increased year by year, especially among residential users. However, the upgrading and renovation of power distribution lines in factories, mines, residential areas, and shops have lagged behind, resulting in voltages at the end of the lines being lower than standard, large voltage fluctuations, and frequent grid overloads. This makes it difficult for some electrical appliances to operate normally and easily causes damage. In addition, newly added motors, compressors, and other equipment have high reactive power requirements, generating a large amount of high-order harmonic currents, leading to increased low-voltage line losses, a decrease in the power factor of the grid, and exacerbated voltage fluctuations.

[0003] To address the issues of low voltage and voltage fluctuations, a technological solution involves installing voltage stabilization devices on the distribution network. These automatic voltage regulators can adjust the supply voltage in real time, stabilizing it at a standard value. This directly provides reactive power to electrical equipment, increases the transmission capacity of the distribution network, enhances the operational safety of power transformers, and significantly mitigates abnormal conditions such as voltage flicker caused by lightning strikes or short circuits, thus protecting the safety of electrical equipment.

[0004] However, in the process of real-time adjustment of power supply through voltage automatic regulation devices of related technologies, there are often circuit impedance mismatches, ripple, noise and other issues. The relevant technologies have not yet proposed effective technical solutions and urgently need to be improved. Utility Model Content

[0005] The main objective of this application is to provide a power supply voltage regulation device based on an inverter circuit, so as to solve the problems of impedance mismatch, ripple, and noise in real-time power supply regulation in related technologies.

[0006] According to a first aspect of the embodiments of this application, a power supply voltage regulation device based on an inverter circuit is provided. The device includes an input circuit, a voltage regulating circuit, an inverter circuit, and a freewheeling circuit. The input circuit includes an input terminal, an output terminal, and a common terminal. The input terminal is coupled to one end of an input AC power supply, and the common terminal is coupled to the other end of the input AC power supply or a neutral wire. The input circuit filters the input AC power supply and outputs it through the output terminal of the input circuit. The voltage regulating circuit includes a first switching device group and a second switching device group. The first switching device group and the second switching device group are connected in series to form a series circuit. One end of the series circuit is coupled to the output terminal of the input circuit, and the other end of the series circuit is coupled to the other end of the input AC power supply or a neutral wire. The midpoint of the series circuit serves as the output terminal of the voltage regulating circuit. The voltage regulating circuit regulates the power supply voltage by adjusting the first switching device group and the second switching device group. The modulation of the operating state of the switching devices in the switching device group realizes the regulation of the input AC power and outputs voltage through the output terminal of the voltage regulating circuit. At the same time, it serves as the output terminal of the power supply voltage regulating device based on the inverter circuit to supply power to the load. The inverter circuit includes two AC ports and two DC ports. The two DC ports of the inverter circuit are respectively coupled to the two DC ports of the freewheeling circuit. The inverter circuit is configured to regulate the DC voltage input to the inverter circuit, regulate the reactive current and harmonic current of the input AC power or the output terminal of the power supply voltage regulating device. The freewheeling circuit includes an input port and two DC ports. The input port of the freewheeling circuit is coupled to the voltage regulating circuit, and the two DC ports of the freewheeling circuit are coupled to the two DC ports of the inverter circuit. The freewheeling circuit is configured to form a freewheeling path between the voltage regulating circuit and the inverter circuit, absorbing the overvoltage and voltage spikes generated by the voltage regulating circuit.

[0007] Optionally, the first switching device group of the voltage regulating circuit includes a first transistor and a second transistor connected in series, and the second switching device group includes a third transistor and a fourth transistor connected in series.

[0008] Optionally, the freewheeling circuit includes an input port and two diodes connected in series in the same direction. The two endpoints formed by the series connection serve as two DC ports of the freewheeling circuit, and the node between the two diodes serves as an input port of the freewheeling circuit, and is coupled to the node between the first switching device group and the second switching device group of the voltage regulating circuit.

[0009] Optionally, the freewheeling circuit includes two input ports and two diodes. The cathode of one diode is coupled to the positive terminal of the DC port of the inverter circuit, and the anode of the other diode is coupled to the negative terminal of the DC port of the inverter circuit. The anode of one diode and the cathode of the other diode serve as the two input ports of the freewheeling circuit, and are respectively coupled to the intermediate node of the two transistors in the first switching device group and the intermediate node of the two transistors connected in series in the second switching device group.

[0010] Optionally, one AC port of the inverter circuit is coupled to the output terminal of the input circuit, or the output terminal of the voltage regulation circuit, or the output terminal of the power supply voltage regulation device based on the inverter circuit. The other AC port of the inverter circuit is coupled to the other end of the input AC power or the neutral line. The inverter circuit includes an inverter bridge arm, two DC support capacitors, and a first inductor. The inverter bridge arm is composed of two transistors connected in series, and the positive and negative terminals of the inverter bridge arm constitute two DC ports of the inverter circuit. The two DC support capacitors are connected in series, and the two endpoints formed by the series connection are coupled to the positive and negative terminals of the inverter bridge arm, respectively. The node in the middle of the two DC support capacitors serves as another AC port of the inverter circuit. The two DC support capacitors are used to stabilize the DC voltage of the inverter circuit. One end of the first inductor is coupled to the midpoint of the inverter bridge arm, and the other end of the first inductor serves as an AC port of the inverter circuit. The first inductor is used to filter out the high-frequency pulsating current of the output current of the inverter circuit.

[0011] Optionally, one AC port of the inverter circuit is coupled to the output terminal of the input circuit, or the output terminal of the voltage regulating circuit, or the output terminal of the power supply voltage regulating device based on the inverter circuit. The other AC port of the inverter circuit is coupled to the other end of the input AC power or the neutral line. The inverter circuit includes two inverter bridge arms, a DC support capacitor, and a second inductor. Each inverter bridge arm consists of two transistors connected in series. The positive terminals of the two inverter bridge arms are coupled to form one DC port of the inverter circuit, and the negative terminals of the two inverter bridge arms are coupled to form the other DC port of the inverter circuit. The DC support capacitor is connected in parallel with the two inverter bridge arms. One end of the second inductor is coupled to the midpoint of one inverter bridge arm, and the other end of the second inductor serves as one AC port of the inverter circuit. The midpoint of the other inverter bridge arm serves as the other AC port of the inverter circuit.

[0012] Optionally, the input circuit includes a first capacitor, wherein one end of the first capacitor is coupled to the input terminal of the input circuit and serves as the output terminal of the input circuit, and the other end of the first capacitor serves as the common terminal of the input circuit and is coupled to the other end of the input AC power or the neutral line.

[0013] Optionally, the input circuit includes a third inductor and a second capacitor, wherein one end of the third inductor is coupled to the input terminal of the input circuit, and the other end of the third inductor is coupled to one end of the second capacitor and serves as the output terminal of the input circuit; the other end of the second capacitor serves as the common terminal of the input circuit and is coupled to the other end of the input AC power or the neutral line.

[0014] Optionally, the device further includes an output circuit, which includes a fourth inductor and a third capacitor. One end of the fourth inductor is coupled to the output terminal of the voltage regulation circuit, and the other end of the fourth inductor is coupled to one end of the third capacitor and serves as an output port of the power supply voltage regulation device based on the inverter circuit. The other end of the third capacitor is coupled to the other end of the input AC power or the neutral line. The fourth inductor and the third capacitor are used to eliminate voltage ripple and current ripple at the output terminal of the voltage regulation circuit and are coupled to the load.

[0015] According to a second aspect of the embodiments of this application, a power supply voltage regulation device based on an inverter circuit is provided. The device includes three input circuits, three voltage regulating circuits, an inverter circuit, and a freewheeling circuit. Each input circuit includes an input terminal, an output terminal, and a common terminal. The input terminal is coupled to one phase of the three-phase input AC power, and the common terminal is coupled to the neutral line of the three-phase input AC power. The three input circuits filter the three-phase input AC power and output it through the output terminals of the three input circuits. Each voltage regulating circuit includes a first switching device group and a second switching device group. The first switching device group and the second switching device group are connected in series to form a series circuit. One end of the series circuit is coupled to the output terminal of an input circuit, and the other end of the series circuit is coupled to the neutral line of the three-phase input AC power. The midpoint of the series circuit serves as the output terminal of the voltage regulating circuit. Each voltage regulating circuit regulates its own first switching device. The modulation of the operating states of the switching devices in the device group and the second switching device group enables the regulation of the three-phase input AC power, and outputs three-phase voltage through the output terminals of the three voltage regulating circuits to supply the load. The inverter circuit includes three AC ports and two DC ports. The two DC ports of the inverter circuit are respectively coupled to the two DC ports of the freewheeling circuit. The inverter circuit is configured to regulate the DC voltage input to the inverter circuit, regulate the reactive current and harmonic current at the output terminal of the three-phase input AC power or the power supply voltage regulating device. The freewheeling circuit includes an input port and two DC ports. The input port of the freewheeling circuit is respectively coupled to the three voltage regulating circuits. The two DC ports of the freewheeling circuit are coupled to the two DC ports of the inverter circuit. The freewheeling circuit is configured to form a freewheeling path between the three voltage regulating circuits and the inverter circuit, absorbing the overvoltage and voltage spikes generated by the three voltage regulating circuits.

[0016] Optionally, the first switching device group includes a first transistor and a second transistor connected in series, and the second switching device group includes a third transistor and a fourth transistor connected in series.

[0017] Optionally, the freewheeling circuit includes three input ports. The freewheeling circuit includes three sets of diodes connected in series in pairs, each forming two endpoints. The first endpoint of each set of diodes connected in series in pairs is coupled to serve as one DC port of the freewheeling circuit, and the second endpoint of each set of diodes connected in series in pairs is coupled to serve as the other DC port of the freewheeling circuit. The three intermediate nodes of the three sets of diodes connected in series in pairs constitute the three input ports of the freewheeling circuit, and are respectively coupled to the intermediate nodes of the first switching device group and the second switching device group of the three voltage regulating circuits.

[0018] Optionally, the freewheeling circuit includes six input ports. The freewheeling circuit includes a first group of diodes and a second group of diodes. The first group of diodes includes three diodes, whose cathodes are mutually coupled and coupled to the positive terminal of the DC port of the inverter circuit. The anodes of the three diodes constitute three input ports of the freewheeling circuit and are respectively coupled to the intermediate node of two transistors connected in series in the first or second switching device group of the three voltage regulating circuits. The second group of diodes includes another three diodes, whose anodes are mutually coupled and coupled to the negative terminal of the DC port of the inverter circuit. The cathodes of the other three diodes constitute the other three input ports of the freewheeling circuit and are respectively coupled to the intermediate node of two transistors connected in series in the second or first switching device group of the three voltage regulating circuits.

[0019] Optionally, the three AC ports of the inverter circuit are respectively coupled to the output terminals of the three input circuits, or the output terminals of the three voltage regulating circuits, or the output terminal of the power supply voltage regulating device based on the inverter circuit. The two DC ports of the inverter circuit are respectively coupled to the two DC ports of the freewheeling circuit. The inverter circuit includes three inverter bridge arms, a DC support capacitor, and three inductors. Each inverter bridge arm consists of two transistors connected in series. The positive terminals of the three inverter bridge arms are coupled to form one DC port of the inverter circuit, and the negative terminals of the three inverter bridge arms are coupled to form another DC port of the inverter circuit. The DC support capacitor is connected in parallel with the three inverter bridge arms. One end of each of the three inductors is coupled to the three midpoints of the three inverter bridge arms, and the other ends of the three inductors serve as the three AC ports of the inverter circuit.

[0020] Optionally, the DC support capacitor of the inverter circuit includes two sets of capacitors, one above the other. The two sets of capacitors are connected in series, and the two terminals formed by the series connection are respectively coupled to the positive and negative terminals of the inverter bridge arm. The node in the middle of the two sets of capacitors serves as the fourth AC port of the inverter circuit and is coupled to the neutral line of the three-phase input AC power.

[0021] Optionally, the input circuit includes a first capacitor, wherein one end of the first capacitor is coupled to the input terminal of the input circuit and serves as the output terminal of the input circuit, and the other end of the first capacitor serves as the common terminal of the input circuit and is coupled to the neutral wire of the three-phase input AC power.

[0022] Optionally, the device further includes three output circuits, each output circuit including a fourth inductor and a third capacitor. One end of the fourth inductor is coupled to the output terminal of the corresponding voltage regulating circuit, and the other end of the fourth inductor is coupled to one end of the third capacitor and serves as an output port of the power supply voltage regulating device based on the inverter circuit. The other end of the third capacitor is coupled to the neutral wire of the three-phase input AC power. The fourth inductor and the third capacitor are used to eliminate voltage ripple and current ripple at the output terminals of the three voltage regulating circuits and are coupled to the load.

[0023] The beneficial technical effects of the embodiments of this application are:

[0024] The power supply voltage regulation device based on an inverter circuit provided in this application embodiment, by incorporating an inverter circuit and a freewheeling circuit, regulates the reactive current and harmonic current in the circuit through the inverter circuit, as well as regulates the DC voltage input to the inverter circuit and suppresses and absorbs overvoltage. Furthermore, it innovatively organically connects the inverter circuit and the voltage regulation circuit through the freewheeling circuit, more effectively realizing voltage regulation and stabilization based on the inverter circuit. The circuit structure of this application embodiment is simple, reducing equipment costs, effectively ensuring the stability of the power grid voltage, and has advantages such as fast response, low cost, simple control, high reliability, easy maintenance, and efficient operation. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the specific implementation methods or related technologies of this application, the accompanying drawings used in the description of the specific implementation methods or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some implementation methods of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1-3 These are three schematic block diagrams of a power supply voltage regulation device based on an inverter circuit in a single-phase application scenario provided in this application embodiment;

[0027] Figure 4-5 7-8 are four exemplary circuit diagrams of a power supply voltage regulation device based on an inverter circuit in a single-phase application scenario provided in the embodiments of this application;

[0028] Figure 6 This is an exemplary circuit diagram of an inverter circuit in a single-phase application scenario provided in this application embodiment;

[0029] Figure 9 , 14 These are two schematic structural block diagrams of a power supply voltage regulation device based on an inverter circuit in a three-phase application scenario provided in the embodiments of this application;

[0030] Figure 10-11 These are two exemplary circuit diagrams of the freewheeling circuit in a three-phase application scenario provided in the embodiments of this application;

[0031] Figure 12-13 These are two exemplary circuit diagrams of inverter circuits in a three-phase application scenario provided in the embodiments of this application. Detailed Implementation

[0032] To enable those skilled in the art to better understand the embodiments of this application, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the implementation methods of the embodiments of this application, and not all of the implementation methods. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the protection scope of the embodiments of this application.

[0033] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of the embodiments of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of the present application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices.

[0034] It should be noted that, unless otherwise specified, the implementation methods and features described in the embodiments of this application can be combined with each other. The embodiments of this application will now be described in detail with reference to the accompanying drawings and examples.

[0035] The power supply voltage regulation device based on the inverter circuit provided in this application embodiment can be used to provide a stable AC power supply to the load when the grid voltage is unstable or a specific voltage level is required. It can ensure the quality and stability of the output voltage mainly through the organic synergy of the inverter circuit and the voltage regulation circuit.

[0036] like Figure 1-3 As shown, the power supply voltage regulation device 100 based on an inverter circuit provided in this application embodiment includes an input circuit 1, a voltage regulation circuit 2, an inverter circuit 3, and a freewheeling circuit 4.

[0037] The input circuit 1 includes an input terminal 11, an output terminal 12, and a common terminal 13. The input terminal 11 is coupled to one end Ui of the input AC power, and the common terminal 13 is coupled to the other end or neutral line N of the input AC power (the figures in the embodiments of this application are all based on the other end being N as an example. In actual applications, the other end can be other non-zero voltages). The input circuit 1 filters the input AC power and outputs it through the output terminal 12 of the input circuit 1.

[0038] The voltage regulating circuit 2 includes a first switching device group and a second switching device group ( Figure 1-3 (Not shown in the diagram), the first switching device group and the second switching device group are connected in series to form a series circuit. One end 21 of the series circuit is coupled to the output end 12 of the input circuit 1, and the other end 22 of the series circuit is coupled to the other end of the input AC power or the neutral line N. The midpoint of the series circuit serves as the output end 23 of the voltage regulating circuit 2. The voltage regulating circuit 2 regulates the input AC power by modulating the working state of the switching devices in the first and second switching device groups, and outputs voltage through the output end 23 of the voltage regulating circuit 2. At the same time, it serves as the output end Uo of the power supply voltage regulating device based on the inverter circuit to supply power to the load.

[0039] Inverter circuit 3 includes two AC ports (AC1, AC2) and two DC ports (DC+, DC-). The two DC ports (DC+, DC-) of inverter circuit 3 are respectively coupled to the two DC ports (DC+, DC-) of freewheeling circuit 4. Inverter circuit 3 is configured to regulate the reactive current and harmonic current at the output of the input AC power or the power supply voltage regulator. Specifically, when the power grid lacks reactive power, the reactive current output by inverter circuit 3 can be used to supplement the reactive power and improve the power factor of the power grid. Specifically, the output reactive current can be controlled by adjusting the switching operation of the transistors in inverter circuit 3 using PWM. In addition, by regulating inverter circuit 3, harmonic current can be suppressed to further ensure voltage stability. Inverter circuit 3 can also regulate the DC voltage input to inverter circuit 3. Furthermore, when the voltage output by voltage regulator circuit 2 exceeds the preset voltage value (preset stable voltage value), inverter circuit 3 can also act as an absorption circuit to absorb the excess voltage. One of the AC ports AC1 of inverter circuit 3 is coupled to the output terminal 12 of input circuit 1 (e.g., Figure 1 As shown), the reactive current and harmonic current of the input AC power are adjusted; if AC1 is coupled to the output terminal 23 of the voltage regulating circuit 2, or the output terminal Uo of the power supply voltage regulating device based on the inverter circuit (as shown), the reactive current and harmonic current of the input AC power are adjusted; Figure 2 As shown), the reactive current and harmonic current at the output of the power supply voltage regulator are adjusted; the other AC port AC2 of inverter circuit 3 is coupled to the other end of the input AC power or the neutral line N. Further, as... Figure 3 As shown, one of the AC ports AC1 of the inverter circuit 3 can also be coupled to the input AC current Ui to regulate the reactive current and harmonic current of the input AC current.

[0040] The freewheeling circuit 4 includes an input port 41 and two DC ports (DC+, DC-). The input port 41 of the freewheeling circuit 4 is coupled to the voltage regulating circuit 2, and the two DC ports (DC+, DC-) of the freewheeling circuit 4 are coupled to the two DC ports (DC+, DC-) of the inverter circuit 3. The freewheeling circuit 4 is configured to form a freewheeling path between the voltage regulating circuit 2 and the inverter circuit 3, absorbing the overvoltage and voltage spikes generated by the voltage regulating circuit 2, thereby ensuring the stability of the grid voltage.

[0041] Furthermore, such as Figure 4The diagram illustrates an exemplary circuit diagram of a voltage regulating circuit 2, including a first switching device group 5 and a second switching device group 6. The first switching device group 5 includes a first transistor M1 and a second transistor M2 connected in series, and the second switching device group 6 includes a third transistor M3 and a fourth transistor M4 connected in series. One end of the first switching device group 5 is one terminal 21 of the series circuit, and the other end of the first switching device group 5 is coupled to one end of the second switching device group 6. The other end of the second switching device group 6 is the other terminal 22 of the series circuit, and the midpoint E of the series circuit serves as the output terminal 23 of the voltage regulating circuit 2. The first transistor M1 and the second transistor M2 are in opposite directions, as are the third transistor M3 and the fourth transistor M4. Furthermore, it should be noted that in practical applications, the number of transistors in the first switching device group 5 and the second switching device group 6 can be adaptively adjusted; for example, each transistor (the first to fourth transistors) can be simultaneously replaced with a parallel structure of two or more transistors. It should also be noted that the transistors in the voltage regulation circuit 2 can be one or more power semiconductors such as IGBTs and MOSFETs. By controlling the transistors to turn on or off, PWM modulation can be achieved, thereby realizing AC voltage regulation and bidirectional energy transfer. For ease of understanding, the complex peripheral circuitry of the voltage regulation circuit 2 is not fully shown in this embodiment. Those skilled in the art, with their general technical knowledge, can implement the technical solutions for the upper and lower bridge arms (i.e., the first switching device group 5 and the second switching device group 6) and their peripheral circuits, solve the corresponding technical problems, and achieve the corresponding technical effects. For example, those skilled in the art can implement forward and reverse conduction using transistors, and connect a freewheeling diode in parallel with each transistor for transistor protection, providing a freewheeling path for current when the transistor is off, preventing voltage spikes caused by current stagnation. They can also reasonably set up corresponding drive circuits to receive control signals from external sources (e.g., PWM signals, etc.), control the transistors to turn on or off according to the control signals, and set filter inductors according to the requirements of different application scenarios to filter out high-frequency harmonics, making the voltage output smoother.

[0042] Furthermore, such as Figure 4 As shown, the freewheeling circuit 4 includes an input port 41 and two diodes (D1, D2). The two diodes are connected in series in the same direction, and the two endpoints formed by the series connection serve as the two DC ports (DC+, DC-) of the freewheeling circuit 4. The node between the two diodes serves as an input port 41 of the freewheeling circuit 4 and is coupled to the node E between the first switching device group 5 and the second switching device group 6 of the voltage regulating circuit 2.

[0043] Furthermore, such as Figure 5The diagram shows an example of another freewheeling circuit 4. The freewheeling circuit 4 includes two input ports 41 and two diodes (D1 and D2). The cathode of one diode D1 is coupled to the positive terminal DC+ of the DC port of the inverter circuit 3, and the anode of the other diode D2 is coupled to the negative terminal DC- of the DC port of the inverter circuit 3. The anode of one diode D1 and the cathode of the other diode D2 serve as the two input ports 41 of the freewheeling circuit 4, and are coupled to the intermediate node F of the two transistors in the first switching device group 5 and the intermediate node G of the two transistors connected in series in the second switching device group 6, respectively.

[0044] Furthermore, such as Figure 4 As shown in Figure 5, the inverter circuit 3 includes an inverter bridge arm, two DC support capacitors (Cs), and a first inductor L1. The inverter bridge arm is composed of two transistors (M5 and M6) connected in series. The positive and negative terminals of the inverter bridge arm form two DC ports (DC+ and DC-) of the inverter circuit 3. The two DC support capacitors (Cs) are connected in series, and the two ends formed by the series connection are coupled to the positive and negative terminals of the inverter bridge arm, respectively. The node in the middle of the two DC support capacitors (Cs) serves as another AC port AC2 of the inverter circuit 3. The two DC support capacitors (Cs) are used to stabilize the DC voltage of the inverter circuit 3. One end of the first inductor L1 is coupled to the midpoint of the inverter bridge arm, and the other end of the first inductor L1 serves as an AC port AC1 of the inverter circuit 3. The first inductor L1 is used to filter out the high-frequency pulsating current of the output current of the inverter circuit 3.

[0045] Furthermore, this application embodiment also provides another schematic diagram of the inverter circuit 3, such as... Figure 6 As shown, inverter circuit 3 includes two inverter bridge arms (M7, M8) and (M9, M10), a DC support capacitor Cs, and a second inductor L2. Each inverter bridge arm consists of two transistors connected in series. The positive terminals of the two inverter bridge arms are coupled to form one DC port DC+ of inverter circuit 3, and the negative terminals of the two inverter bridge arms are coupled to form the other DC port DC- of inverter circuit 3. The DC support capacitor Cs is connected in parallel with the two inverter bridge arms. One end of the second inductor L2 is coupled to the midpoint of one inverter bridge arm, and the other end of the second inductor L2 serves as one AC port AC1 of inverter circuit 3. The midpoint of the other inverter bridge arm serves as the other AC port AC2 of inverter circuit 3.

[0046] It should be noted that, Figure 4 or Figure 5 Inverter circuit 3 in the diagram is a half-bridge inverter structure with low power consumption. Figure 6Inverter circuit 3 in the diagram is a full-bridge inverter structure with high power, but all of its functions can be achieved by controlling the transistors within it. In practical applications, the specific inverter circuit 3 structure can be selected based on the actual power requirements.

[0047] Furthermore, such as Figure 4 As shown in Figure 5, the input circuit 1 includes a first capacitor C1, wherein one end of the first capacitor C1 is coupled to the input terminal 11 of the input circuit 1 and serves as the output terminal 12 of the input circuit 1, and the other end of the first capacitor C1 serves as the common terminal 13 of the input circuit 1 and is coupled to the other end of the input AC power or the neutral line N.

[0048] Furthermore, another example diagram of the structure of input circuit 1 is also provided, such as... Figure 7 As shown, the input circuit 1 includes a third inductor L3 and a second capacitor C2. One end of the third inductor L3 is coupled to the input terminal 11 of the input circuit 1, and the other end of the third inductor L3 is coupled to one end of the second capacitor C2 and serves as the output terminal 12 of the input circuit 1. The other end of the second capacitor C2 serves as the common terminal 13 of the input circuit 1 and is coupled to the other end of the input AC power or the neutral line N. Figure 7 Input circuit 1 and Figure 4 Compared to option 5, the addition of an inductor can further reduce circuit impedance, decrease circuit ripple, smooth out and remove noise, and improve the stability of the mains voltage input.

[0049] Furthermore, such as Figure 8 As shown, the device also includes an output circuit 7, which includes a fourth inductor L4 and a third capacitor C3. One end of the fourth inductor L4 is coupled to the output terminal 23 of the voltage regulation circuit 2, and the other end of the fourth inductor L4 is coupled to one end of the third capacitor C3, serving as an output port Uo of the power supply voltage regulation device based on the inverter circuit. The other end of the third capacitor C3 is coupled to the other end of the input AC power or the neutral line N. The fourth inductor L4 and the third capacitor C3 are used to eliminate voltage and current ripple at the output terminal 23 of the voltage regulation circuit 2 and are coupled to the load. The fourth inductor L4, as the input inductor at the output terminal Uo, is used to filter out high-frequency components in the voltage and current, eliminate electromagnetic interference, reduce circuit impedance, reduce circuit ripple, smooth and remove noise, and further stabilize the voltage.

[0050] It should be noted that, according to the above description, one AC port AC1 of inverter circuit 3 can be coupled to any one of the following: output terminal 12 of input circuit 1, output terminal 23 of voltage regulation circuit 2, output terminal Uo of power supply voltage regulator, and input AC power Ui. Figure 7 The embodiment is an example of AC1 coupled to the input AC power. Figure 4-6 This example uses the output terminal 12 of input circuit 1 coupled with AC1 as an example. Figure 8 This example uses the output terminal Uo of the AC1 coupled power supply voltage regulator 100 as an example. It can be understood that... Figure 4-8 Each diagram only shows one way of coupling AC1; other coupling methods are not listed. For practical applications, please refer to the preceding sections. Figure 1-3 The structural diagram is obtained from the diagram.

[0051] In summary, the power supply voltage regulation device 100 based on an inverter circuit provided in this application embodiment, by incorporating an inverter circuit and a freewheeling circuit, regulates the reactive current and harmonic current in the circuit through the inverter circuit, regulates the DC voltage input to the inverter circuit, and suppresses and absorbs overvoltage. Furthermore, it creatively connects the inverter circuit and the voltage regulation circuit through the freewheeling circuit, more effectively realizing voltage regulation and stabilization based on the inverter circuit. The circuit structure of this application embodiment is simple, reducing equipment costs, effectively ensuring the stability of the power grid voltage, and has advantages such as fast response, low cost, simple control, high reliability, easy maintenance, and efficient operation.

[0052] The application scenarios of this application include three-phase and single-phase. Three-phase is mostly used in factories and similar scenarios, while single-phase is mostly used in residential power supply scenarios, namely 380V (which can also be written as 0.4kV) and 220V respectively. The power supply scenario can also be verified by comparing the rated voltage marked on the nameplate of the electrical equipment. The aforementioned... Figure 1-8 The embodiments are applied to single-phase scenarios.

[0053] Furthermore, this application embodiment also provides a power supply voltage regulation device 200 based on an inverter circuit in a three-phase scenario. The functions and roles of the three-phase scenario are the same as those of the single-phase scenario, but the structure of some modules needs to be adjusted. The power supply voltage regulation device 200 based on an inverter circuit in a three-phase scenario will be described in detail below.

[0054] like Figure 9As shown, the power supply voltage regulation device 200 based on the inverter circuit includes three input circuits 1, three voltage regulating circuits 2, an inverter circuit 3, and a freewheeling circuit 4. Each input circuit 1 includes an input terminal 11, an output terminal 12, and a common terminal 13. The input terminal 11 is coupled to one phase (UiA, UiB, or UiC) of the three-phase input AC power, and the common terminal 13 is coupled to the neutral line N of the three-phase input AC power. The three input circuits 1 filter the three-phase input AC power (UiA, UiB, UiC, N) and output it through the output terminals 12 of the three input circuits 1. Further, each input circuit 1 includes a first capacitor C1, wherein one end of the first capacitor C1 is coupled to the input terminal 11 of the input circuit 1 and serves as the output terminal 12 of the input circuit 1, and the other end of the first capacitor C1 serves as the common terminal of the input circuit 1 and is coupled to the neutral line N of the three-phase input AC power. Alternatively, as another structure for the input circuit, input circuit 1 includes a third inductor L3 and a second capacitor C2. One end of the third inductor L3 is coupled to the input terminal 11 of input circuit 1, and the other end of the third inductor L3 is coupled to one end of the second capacitor C2, which also serves as the output terminal 12 of input circuit 1. The other end of the second capacitor C2 serves as the common terminal 13 of input circuit 1, coupled to the neutral line. It should be noted that the structure and function of input circuit 1 in the three-phase embodiment are the same as those in the aforementioned single-phase embodiment. Please refer to the corresponding descriptions and illustrations in the aforementioned embodiments; they will not be repeated here.

[0055] Each voltage regulating circuit 2 includes a first switching device group 5 and a second switching device group 6. Figure 9 (Not shown in the diagram), the first switching device group 5 and the second switching device group 6 are connected in series to form a series circuit. One end 21 of the series circuit is coupled to the output end 12 of an input circuit 1, and the other end 22 of the series circuit is coupled to the neutral line N of the three-phase input AC power. The midpoint E of the series circuit serves as the output end 23 of the voltage regulating circuit. Each voltage regulating circuit 2 regulates the three-phase input AC power by modulating the operating state of the switching devices in its respective first switching device group 5 and second switching device group 6, and outputs three-phase voltages (UoA, UoB, UoC, N) through the output ends 23 of the three voltage regulating circuits to supply the load. Further, the first switching device group 5 includes a first transistor M1 and a second transistor M2 connected in series, and the second switching device group 6 includes a third transistor M3 and a fourth transistor M4 connected in series. The structure and function of the voltage regulating circuit 2 in the three-phase embodiment are the same as those in the aforementioned single-phase embodiment, and can be referred to the corresponding descriptions and illustrations in the aforementioned embodiments, which will not be repeated here.

[0056] The inverter circuit 3 includes three AC ports (AC1, AC2, AC3) and two DC ports (DC+, DC-). The inverter circuit 3 is configured to regulate the DC voltage input to the inverter circuit 3, regulate the reactive current and harmonic current of the three-phase input AC power (UiA, UiB, UiC, N) or the output terminals (UoA, UoB, UoC, N) of the power supply voltage regulator.

[0057] The freewheeling circuit 4 includes an input port 41 and two DC ports (DC+, DC-). The input port 41 of the freewheeling circuit 4 is coupled to the three voltage regulating circuits 2 respectively. The two DC ports (DC+, DC-) of the freewheeling circuit 4 are coupled to the two DC ports (DC+, DC-) of the inverter circuit. The freewheeling circuit 4 is configured to form a freewheeling path between the three voltage regulating circuits 2 and the inverter circuit 3, and to absorb the overvoltage and voltage spikes generated by the three voltage regulating circuits 2.

[0058] Furthermore, such as Figure 10 As shown, the freewheeling circuit 4 includes three input ports 41. The freewheeling circuit 4 includes three groups of diodes connected in series in pairs (D1 and D2 as one group, D3 and D4 as one group, and D5 and D6 as one group). Each group of diodes connected in series in pairs forms two endpoints. The first endpoint of each group of diodes connected in series in pairs is coupled to serve as one DC port DC+ of the freewheeling circuit 4, and the second endpoint of each group of diodes connected in series in pairs is coupled to serve as the other DC port DC- of the freewheeling circuit 4. The three intermediate nodes (O, P, Q) of the three groups of diodes connected in series in pairs in pairs form the three input ports 41 of the freewheeling circuit 4. The three input ports 41 are respectively coupled to the node E between the first switching device group 5 and the second switching device group 6 of each voltage regulating circuit 2.

[0059] like Figure 11As shown, another freewheeling circuit 4 is provided, including six input ports 41. The freewheeling circuit 4 includes a first group of diodes (D1, D2, D3) and a second group of diodes (D4, D5, D6). The first group of diodes includes three diodes (D1, D2, D3), wherein the cathodes of the three diodes (D1, D2, D3) are coupled to each other and coupled to the positive terminal of the DC+ port of the inverter circuit 3. The anodes of the three diodes (D1, D2, D3) constitute the three input ports 41 of the freewheeling circuit, and are respectively connected to the intermediate node (F) of the two transistors connected in series in the first or second switching device group of the three voltage regulating circuits 23. Or G, that is, the anodes of D1, D2, and D3 are respectively connected to three F points or three G points; the second group of diodes includes three other diodes (D4, D5, and D6), wherein the anodes of the other three diodes (D4, D5, and D6) are mutually coupled and coupled to the negative DC- terminal of the DC port of the inverter circuit 3. The cathodes of the other three diodes (D4, D5, and D6) form the other three input ports 41 of the freewheeling circuit 4, and are respectively coupled to the intermediate nodes (G or F, that is, the cathodes of D4, D5, and D6 are respectively connected to three G points or three F points) of the two transistors connected in series in the second switching device group or the first switching device group of the three voltage regulating circuits 2. It should be noted that Figure 10 and 11 Compared to the two freewheeling circuits 4, Figure 10 The cost is lower. Figure 11 It has a lower freewheeling voltage, and different circuit structures can be selected according to actual needs in practical applications.

[0060] Furthermore, the three AC ports (AC1, AC2, AC3) of the inverter circuit 3 are respectively coupled to the output terminals 12 of the three input circuits 1 (e.g., ...). Figure 9 (as shown), or the output terminal 23 of the three voltage regulating circuits (refer to) Figure 2 As shown, the coupling methods of AC1, AC2, and AC3 are all the same as... Figure 2 (The connection method of AC1 is the same), or the output terminal of the power supply voltage regulator based on the inverter circuit (see...) Figure 2 or Figure 8 As shown, the coupling methods of AC1, AC2, and AC3 are all the same as... Figure 2 Or the connection method of AC1 in 8 is the same, such as Figure 9 As shown, the two DC ports (DC+, DC-) of inverter circuit 3 are respectively coupled to the two DC ports (DC+, DC-) of freewheeling circuit 4, and further as... Figure 12As shown, a structural diagram of an inverter circuit 3 is provided, including three inverter bridge arms (one bridge arm of M5 and M6, one bridge arm of M7 and M8, and one bridge arm of M9 and M10), a DC support capacitor Cs, and three inductors (L5, L6, and L7). Each inverter bridge arm consists of two transistors connected in series. The positive terminals of the three inverter bridge arms are coupled to form one DC port DC+ of the inverter circuit 3, and the negative terminals of the three inverter bridge arms are coupled to form another DC port DC- of the inverter circuit 3. The DC support capacitor Cs is connected in parallel with the three inverter bridge arms. One end of each of the three inductors (L5, L6, and L7) is coupled to the three midpoints (X, Y, and Z) of the three inverter bridge arms, and the other ends of the three inductors (L5, L6, and L7) serve as the three AC ports (AC1, AC2, and AC3) of the inverter circuit 3. Furthermore, similar to inverter circuit 3 in the single-phase embodiment, the three AC ports (AC1, AC2, AC3) of inverter circuit 3 can also be coupled to three-phase input AC power (UiA, UiB, UiC), as detailed in the following reference. Figure 3 The connection method of AC1 is shown in the figure.

[0061] Furthermore, such as Figure 13 As shown, the DC support capacitor Cs of the inverter circuit 3 can include two sets of capacitors (C4 and C5). The two sets of capacitors (C4 and C5) are connected in series, and the two terminals formed after the series connection are coupled to the positive DC+ and negative DC- terminals of the inverter bridge arm, respectively. The node T in the middle of the two sets of capacitors serves as the fourth AC port AC4 of the inverter circuit and is coupled to the neutral line N of the three-phase input AC power.

[0062] Furthermore, such as Figure 14 As shown, the device also includes three output circuits 7. Each output circuit 7 includes a fourth inductor L4 and a third capacitor C3. One end of the fourth inductor L4 is coupled to the output terminal 23 of each voltage regulating circuit 2, and the other end of the fourth inductor L4 is coupled to one end of the third capacitor C3, serving as an output port (UoA, UoB, or UoC) of the power supply voltage regulation device based on the inverter circuit. The other end of the third capacitor C3 is coupled to the neutral line N of the three-phase input AC power. The fourth inductor L4 and the third capacitor C3 are used to eliminate voltage ripple and current ripple at the output terminals 23 of the three voltage regulating circuits 2 and are coupled to the load. The structure and function of the output circuit 7 in the three-phase embodiment are the same as those in the single-phase embodiment described above. Please refer to the corresponding descriptions and illustrations in the aforementioned embodiments, which will not be repeated here.

[0063] In summary, the embodiments of this application stabilize the grid voltage at a preset voltage value through the coordinated operation of multiple functional modules, providing a stable and reliable voltage supply for the load equipment, ensuring the normal operation and performance of the load equipment, and exhibiting strong adaptability and flexibility, thereby achieving stable regulation and efficient transmission of grid voltage.

[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this invention and form different embodiments. For example, any one of the embodiments claimed in the claims can be used in any combination of embodiments of this application.

[0066] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein, and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the specific implementation methods of the embodiments of this application.

Claims

1. A power supply voltage regulation device based on an inverter circuit, characterized in that, The device includes an input circuit, a voltage regulation circuit, an inverter circuit, and a freewheeling circuit. The input circuit includes an input terminal, an output terminal, and a common terminal. The input terminal is coupled to one end of the input AC power, and the common terminal is coupled to the other end of the input AC power or the neutral wire. The input circuit filters the input AC power and outputs it through the output terminal of the input circuit. The voltage regulating circuit includes a first switching device group and a second switching device group. The first switching device group and the second switching device group are connected in series to form a series circuit. One end of the series circuit is coupled to the output end of the input circuit, and the other end of the series circuit is coupled to the other end of the input AC power or the neutral line. The midpoint of the series circuit serves as the output end of the voltage regulating circuit. The voltage regulating circuit regulates the input AC power by modulating the operating states of the switching devices in the first and second switching device groups, and outputs voltage through the output end of the voltage regulating circuit. At the same time, it serves as the output end of the power supply voltage regulating device based on the inverter circuit to supply power to the load. The inverter circuit includes two AC ports and two DC ports. The two DC ports of the inverter circuit are respectively coupled to the two DC ports of the freewheeling circuit. The inverter circuit is configured to regulate the DC voltage input to the inverter circuit, regulate the reactive current and harmonic current at the output of the input AC power or the power supply voltage regulator. The freewheeling circuit includes an input port and two DC ports. The input port of the freewheeling circuit is coupled to the voltage regulating circuit, and the two DC ports of the freewheeling circuit are coupled to the two DC ports of the inverter circuit. The freewheeling circuit is configured to form a freewheeling path between the voltage regulating circuit and the inverter circuit, and to absorb overvoltages and voltage spikes generated by the voltage regulating circuit.

2. The power supply voltage regulation device based on an inverter circuit according to claim 1, characterized in that, The first switching device group of the voltage regulating circuit includes a first transistor and a second transistor connected in series, and the second switching device group includes a third transistor and a fourth transistor connected in series.

3. The power supply voltage regulation device based on an inverter circuit according to claim 1, characterized in that, The freewheeling circuit includes an input port and two diodes connected in series in the same direction. The two endpoints formed by the series connection serve as two DC ports of the freewheeling circuit, and the node between the two diodes serves as an input port of the freewheeling circuit. The freewheeling circuit is coupled to the node between the first switching device group and the second switching device group of the voltage regulating circuit.

4. The power supply voltage regulation device based on an inverter circuit according to claim 2, characterized in that, The freewheeling circuit includes two input ports and two diodes. The cathode of one diode is coupled to the positive terminal of the DC port of the inverter circuit, and the anode of the other diode is coupled to the negative terminal of the DC port of the inverter circuit. The anode of one diode and the cathode of the other diode serve as the two input ports of the freewheeling circuit, and are respectively coupled to the intermediate node of the two transistors in the first switching device group and the intermediate node of the two transistors connected in series in the second switching device group.

5. The power supply voltage regulation device based on an inverter circuit according to claim 1, characterized in that, One AC port of the inverter circuit is coupled to the output terminal of the input circuit, or the output terminal of the voltage regulation circuit, or the output terminal of the power supply voltage regulation device based on the inverter circuit. The other AC port of the inverter circuit is coupled to the other end of the input AC power or the neutral line. The inverter circuit includes an inverter bridge arm, two DC support capacitors, and a first inductor. The inverter bridge arm is composed of two transistors connected in series, and the positive and negative terminals of the inverter bridge arm constitute the two DC ports of the inverter circuit. The two DC support capacitors are connected in series, and the two ends formed by the series connection are respectively coupled to the positive and negative terminals of the inverter bridge arm. The node in the middle of the two DC support capacitors serves as another AC port of the inverter circuit. The two DC support capacitors are used to stabilize the DC voltage of the inverter circuit. One end of the first inductor is coupled to the midpoint of the inverter bridge arm, and the other end of the first inductor serves as an AC port of the inverter circuit. The first inductor is used to filter out the high-frequency pulsating current of the output current of the inverter circuit.

6. The power supply voltage regulation device based on an inverter circuit according to claim 1, characterized in that, One AC port of the inverter circuit is coupled to the output terminal of the input circuit, or the output terminal of the voltage regulation circuit, or the output terminal of the power supply voltage regulation device based on the inverter circuit. The other AC port of the inverter circuit is coupled to the other end of the input AC power or the neutral line. The inverter circuit includes two inverter bridge arms, a DC support capacitor, and a second inductor. Each inverter bridge arm consists of two transistors connected in series, with the positive terminals of the two inverter bridge arms coupled together to form one DC port of the inverter circuit, and the negative terminals of the two inverter bridge arms coupled together to form the other DC port of the inverter circuit. The DC support capacitor is connected in parallel with the two inverter bridge arms; One end of the second inductor is coupled to the midpoint of one inverter bridge arm, and the other end of the second inductor serves as one AC port of the inverter circuit, while the midpoint of the other inverter bridge arm serves as another AC port of the inverter circuit.

7. The power supply voltage regulation device based on an inverter circuit according to claim 1, characterized in that, The input circuit includes a first capacitor. One end of the first capacitor is coupled to the input terminal of the input circuit and serves as the output terminal of the input circuit. The other end of the first capacitor serves as the common terminal of the input circuit and is coupled to the other end of the input AC power or the neutral line.

8. The power supply voltage regulation device based on an inverter circuit according to claim 1, characterized in that, The input circuit includes a third inductor and a second capacitor. Wherein, one end of the third inductor is coupled to the input terminal of the input circuit, and the other end of the third inductor is coupled to one end of the second capacitor and also serves as the output terminal of the input circuit; The other end of the second capacitor serves as the common terminal of the input circuit, coupled to the other end of the input AC power or the neutral line.

9. The power supply voltage regulation device based on an inverter circuit according to claim 1, characterized in that, The device further includes an output circuit, which comprises a fourth inductor and a third capacitor. Wherein, one end of the fourth inductor is coupled to the output terminal of the voltage regulation circuit, and the other end of the fourth inductor is coupled to one end of the third capacitor, and also serves as an output port of the power supply voltage regulation device based on the inverter circuit; The other end of the third capacitor is coupled to the other end of the input AC power or the neutral wire; The fourth inductor and the third capacitor are used to eliminate voltage ripple and current ripple at the output of the voltage regulation circuit and are coupled to the load.

10. A power supply voltage regulation device based on an inverter circuit, characterized in that, The device includes three input circuits, three voltage regulation circuits, an inverter circuit, and a freewheeling circuit. Each input circuit includes an input terminal, an output terminal, and a common terminal. The input terminal is coupled to one phase of the three-phase AC input power, and the common terminal is coupled to the neutral wire of the three-phase AC input power. The three input circuits filter the three-phase AC input power and output it through the output terminals of the three input circuits. Each voltage regulating circuit includes a first switching device group and a second switching device group. The first and second switching device groups are connected in series to form a series circuit. One end of the series circuit is coupled to the output of an input circuit, and the other end of the series circuit is coupled to the neutral line of the three-phase input AC power. The midpoint of the series circuit serves as the output of the voltage regulating circuit. Each voltage regulating circuit regulates the three-phase input AC power by modulating the operating state of the switching devices in its respective first and second switching device groups, and outputs three-phase voltage through the outputs of the three voltage regulating circuits to supply the load. The inverter circuit includes three AC ports and two DC ports. The inverter circuit is configured to regulate the DC voltage input to the inverter circuit, regulate the reactive current and harmonic current at the output of the three-phase input AC power or the power supply voltage regulator. The freewheeling circuit includes an input port and two DC ports. The input port of the freewheeling circuit is coupled to the three voltage regulating circuits respectively. The two DC ports of the freewheeling circuit are coupled to the two DC ports of the inverter circuit. The freewheeling circuit is configured to form a freewheeling path between the three voltage regulating circuits and the inverter circuit, and to absorb the overvoltage and voltage spikes generated by the three voltage regulating circuits.

11. The power supply voltage regulation device based on an inverter circuit according to claim 10, characterized in that, The first switching device group includes a first transistor and a second transistor connected in series, and the second switching device group includes a third transistor and a fourth transistor connected in series.

12. The power supply voltage regulation device based on an inverter circuit according to claim 10, characterized in that, The freewheeling circuit includes three input ports and three sets of diodes connected in series in pairs, each in the same direction. Each group of diodes connected in series in the same direction forms two terminals. The first terminal of each group of diodes connected in series in the same direction is coupled to serve as one DC port of the freewheeling circuit, and the second terminal of each group of diodes connected in series in the same direction is coupled to serve as the other DC port of the freewheeling circuit. The three intermediate nodes of the three sets of diodes connected in series in the same direction constitute the three input ports of the freewheeling circuit, and are respectively coupled to the intermediate nodes of the first switching device group and the second switching device group of the three voltage regulating circuits.

13. The power supply voltage regulation device based on an inverter circuit according to claim 11, characterized in that, The freewheeling circuit includes six input ports and comprises a first group of diodes and a second group of diodes. The first group of diodes includes three diodes, wherein the cathodes of the three diodes are coupled to each other and to the positive terminal of the DC port of the inverter circuit, and the anodes of the three diodes constitute the three input ports of the freewheeling circuit, and are respectively coupled to the intermediate node of the two transistors connected in series in the first or second switching device group of the three voltage regulating circuits. The second group of diodes includes three additional diodes, wherein the anodes of the other three diodes are coupled to each other and to the negative terminal of the DC port of the inverter circuit, and the cathodes of the other three diodes constitute the other three input ports of the freewheeling circuit, and are respectively coupled to the intermediate node of the two transistors connected in series in the second switching device group or the first switching device group of the three voltage regulating circuits.

14. The power supply voltage regulation device based on an inverter circuit according to claim 10, characterized in that, The three AC ports of the inverter circuit are respectively coupled to the output terminals of the three input circuits, or the output terminals of the three voltage regulating circuits, or the output terminal of the power supply voltage regulating device based on the inverter circuit. The two DC ports of the inverter circuit are respectively coupled to the two DC ports of the freewheeling circuit. The inverter circuit includes three inverter bridge arms, a DC support capacitor, and three inductors. Each inverter bridge arm consists of two transistors connected in series, and the positive terminals of the three inverter bridge arms are coupled together to form one DC port of the inverter circuit. The negative terminals of the three inverter bridge arms are coupled together to form another DC port of the inverter circuit. The DC support capacitor is connected in parallel with the three inverter bridge arms; One end of each of the three inductors is coupled to the three midpoints of the three inverter bridge arms, and the other ends of the three inductors serve as the three AC ports of the inverter circuit.

15. The power supply voltage regulation device based on an inverter circuit according to claim 14, characterized in that, The DC support capacitor of the inverter circuit includes two sets of capacitors, one above the other. The two sets of capacitors are connected in series, and the two terminals formed by the series connection are respectively coupled to the positive and negative terminals of the inverter bridge arm. The node in the middle of the two sets of capacitors serves as the fourth AC port of the inverter circuit and is coupled to the neutral line of the three-phase input AC power.

16. The power supply voltage regulation device based on an inverter circuit according to claim 10, characterized in that, The input circuit includes a first capacitor. One end of the first capacitor is coupled to the input terminal of the input circuit and serves as the output terminal of the input circuit. The other end of the first capacitor serves as the common terminal of the input circuit and is coupled to the neutral wire of the three-phase input AC power.

17. The power supply voltage regulation device based on an inverter circuit according to claim 10, characterized in that, The device also includes three output circuits, each of which includes a fourth inductor and a third capacitor. Wherein, one end of the fourth inductor is coupled to the output terminal of the corresponding voltage regulation circuit, and the other end of the fourth inductor is coupled to one end of the third capacitor and also serves as an output port of the power supply voltage regulation device based on the inverter circuit; The other end of the third capacitor is coupled to the neutral wire of the three-phase input AC power. The fourth inductor and the third capacitor are used to eliminate voltage ripple and current ripple at the output terminals of the three voltage regulating circuits and are coupled to the load.

Images