Switch module and power transmission apparatus

Abstract

The present disclosure provides a switch module and a power transmission apparatus. The switch module comprises: a first switch circuit, a first snubber circuit, a first pre-charge circuit, and a first discharge circuit. The first switch circuit is configured to be turned on or off on the basis of an instruction received at a first control terminal. The first pre-charge circuit is in series connection with the first snubber circuit and is then in parallel connection with the first switch circuit, and the first pre-charge circuit is configured to limit the inrush current when the first snubber circuit is connected, and to charge the first snubber circuit in advance. The first snubber circuit is configured to absorb electrical energy generated during operation of the first pre-charge circuit and the first switch circuit. A first rectifying unit is configured to rectify a current generated during a switching process of a switch unit. The first discharge circuit is electrically connected to the first switch circuit by means of the first snubber circuit, and the first discharge circuit is configured to discharge energy stored in the first snubber circuit.

Description

Switching modules and power transmission equipment

[0001] Cross-referencing

[0002] This disclosure incorporates, in its entirety, Chinese Patent Application No. 202411786745.5, filed on December 6, 2024, entitled “A Switch Module and Power Transmission Device”. Technical Field

[0003] This disclosure relates to the field of smart grid technology, and in particular to a switch module and a power transmission device. Background Technology

[0004] AC electronic switches, also known as solid-state electronic switches, can control the switching of alternating current. They are often implemented using parallel thyristors. AC electronic switches can be easily controlled by low-voltage signals, such as MCUs, making them very convenient for various applications and showing great promise. However, current AC electronic switches suffer from technical problems such as complex circuit structure, high cost, low reliability, and slow response speed. Summary of the Invention

[0005] This disclosure provides a switching module and a power transmission device, aiming to solve at least one of the technical problems in the aforementioned related technologies. The switching module of this disclosure simplifies the circuit structure and achieves a higher response speed, further reducing the manufacturing cost of AC electronic switches.

[0006] The first aspect of this disclosure provides a switching module, including: a first switching circuit, a first absorption circuit, a first pre-charge circuit, and a first discharge circuit;

[0007] The first switching circuit is configured to turn on or off according to the instruction received from the first control terminal. The first switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the first switching circuit.

[0008] The first pre-charge circuit is connected in series with the first absorption circuit and then in parallel with the first switch circuit. The first pre-charge circuit is configured to limit the current of the first absorption circuit at the moment of connection and to pre-charge the first absorption circuit. The first pre-charge circuit includes: a first pre-charge resistor and a first switch, which are connected in parallel.

[0009] The first absorption circuit is configured to absorb the electrical energy generated when the first pre-charging circuit and the first switching circuit are working. The first absorption circuit includes: a first rectifier unit and a first absorption unit, the first absorption unit being electrically connected to the first rectifier unit; the first rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the first rectifier unit including at least three sets of diodes connected in series; the first absorption unit is configured to absorb the electrical energy generated during the turn-off process of the first switching circuit, the first absorption unit including at least one capacitor.

[0010] The first discharge circuit is electrically connected to the first switching circuit through the first absorption circuit, and the first discharge circuit is configured to release the energy stored in the first absorption circuit.

[0011] The switch module is controlled by a first control terminal, which is connected to the switch module and configured to control the switch module according to received instructions from a host computer.

[0012] In some embodiments, the first switching circuit includes at least a first switching unit and a second switching unit;

[0013] The first switching unit includes at least a first semiconductor switching device and a first diode. The drain and source of the first semiconductor switching device are respectively connected to the power grid input terminal and the positive terminal of the first diode, and the negative terminal of the first diode is connected to the load.

[0014] The second switching unit includes at least a second semiconductor switching device and a second diode. The source and drain of the second semiconductor switching device are respectively connected to the power grid input terminal and the negative terminal of the second diode, and the positive terminal of the second diode is connected to the load.

[0015] In some real-time applications, semiconductor switching devices are reverse-conducting power semiconductor devices.

[0016] In some real-time configurations, the first rectifier unit and the first absorber unit are connected in series in the first absorption circuit.

[0017] In the first rectifier unit, diodes connected in series in pairs are connected in forward direction in each group; the groups of diodes connected in series in pairs are connected in parallel and in parallel with the capacitor.

[0018] In some real-time methods, in the first absorption circuit:

[0019] The input and output terminals of the first switching circuit are electrically connected to the midpoints of the series-connected diodes of each group in the first rectifier unit, respectively.

[0020] The first rectifier unit is connected to the neutral wire of the power grid.

[0021] In some real-time methods, the first discharge circuit includes:

[0022] At least one discharge resistor,

[0023] A semiconductor switching transistor or mechanical switch is connected in series with a discharge resistor;

[0024] One end of the first discharge circuit is connected to the ground wire.

[0025] In some real-time configurations, the switching module further includes: a second switching circuit, a second absorption circuit, a second pre-charge circuit, a third switching circuit, a third absorption circuit, and a third pre-charge circuit;

[0026] The second switching circuit is configured to turn on or off according to the command received from the second control terminal. The second switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the second switching circuit.

[0027] The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switching circuit. The second pre-charge circuit is configured to limit the current of the second absorption circuit at the moment of connection and to pre-charge the second absorption circuit. The second pre-charge circuit includes: a second pre-charge resistor and a second switch, with the second pre-charge resistor connected in parallel with the second switch.

[0028] The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charge circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least three sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor.

[0029] The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit.

[0030] The third pre-charge circuit is connected in series with the third absorption circuit and then in parallel with the third switch circuit. The third pre-charge circuit is configured to limit the current of the third absorption circuit at the moment of connection and to pre-charge the third absorption circuit. The third pre-charge circuit includes: a third pre-charge resistor and a third switch, with the third pre-charge resistor and the third switch connected in parallel.

[0031] The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charging circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, with the third absorption unit electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least three sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor.

[0032] One end of the second absorption circuit is connected to the neutral wire of the power grid through the fifth node and the first node, and one end of the third absorption circuit is connected to the neutral wire of the power grid through the sixth node and the first node;

[0033] The other end of the second absorption circuit is electrically connected to the third and fourth nodes of the first discharge circuit through the second and seventh nodes, and the other end of the third absorption circuit is electrically connected to the third and fourth nodes of the first discharge circuit through the ninth and eighth nodes.

[0034] In some real-time configurations, the switching module further includes: a second switching circuit, a second absorption circuit, a second pre-charge circuit, a second discharge circuit, a third switching circuit, a third absorption circuit, a third pre-charge circuit, and a third discharge circuit;

[0035] The second switching circuit is configured to turn on or off according to the command received from the second control terminal. The second switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the second switching circuit.

[0036] The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switching circuit. The second pre-charge circuit is configured to limit the current of the second absorption circuit at the moment of connection and to pre-charge the second absorption circuit. The second pre-charge circuit includes: a second pre-charge resistor and a second switch, with the second pre-charge resistor connected in parallel with the second switch.

[0037] The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charge circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least three sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor.

[0038] The second discharge circuit is electrically connected to the second switching circuit through the second absorption circuit, and the second discharge circuit is configured to release the energy stored in the second absorption circuit.

[0039] The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit.

[0040] The third pre-charge circuit is connected in series with the third absorption circuit and then in parallel with the third switch circuit. The third pre-charge circuit is configured to limit the current of the third absorption circuit at the moment of connection and to pre-charge the third absorption circuit. The third pre-charge circuit includes: a third pre-charge resistor and a third switch, with the third pre-charge resistor and the third switch connected in parallel.

[0041] The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charging circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, with the third absorption unit electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least three sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor.

[0042] The third discharge circuit is electrically connected to the third switching circuit through the third absorption circuit. The third discharge circuit is configured to release the energy stored in the second absorption circuit.

[0043] The second absorption circuit is connected to the neutral wire of the power grid through the fifth node and the first node, and the third absorption circuit is connected to the neutral wire of the power grid through the sixth node and the first node.

[0044] According to another aspect of this disclosure, a second aspect of this disclosure provides another switching module, including: a first switching module, a second switching module, and a third switching module;

[0045] The first switching module includes: a first switching circuit, a first absorption circuit, a first pre-charge circuit, and a first discharge circuit; the first switching circuit is configured to turn on or off according to a command received from a first control terminal, and the first switching circuit includes at least two switching units connected in anti-parallel; the switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current; the switching unit includes at least one semiconductor switching device and a diode, the semiconductor switching device and the diode being connected in series; at least two switching units are connected in anti-parallel to form the first switching circuit;

[0046] The first pre-charging circuit is connected in series with the first absorption circuit and then in parallel with the first switching circuit. The first pre-charging circuit is configured to limit the current at the moment the first switching module is connected and to pre-charge the first absorption circuit. The first pre-charging circuit includes a first pre-charging resistor and a first switch, with the first pre-charging resistor connected in parallel with the first switch. The first absorption circuit is configured to absorb the electrical energy generated when the first pre-charging circuit and the first switching circuit are working. The first absorption circuit includes a first rectifier unit and a first absorption unit, with the first absorption unit electrically connected to the first rectifier unit. The first rectifier unit is configured to rectify the current generated during the switching process of the switching unit and includes at least two sets of diodes connected in series. The first absorption unit is configured to absorb the electrical energy generated during the turn-off process of the first switching circuit and includes at least one capacitor.

[0047] The first discharge circuit is electrically connected to the first switching circuit through the first absorption circuit, and the first discharge circuit is configured to release the energy stored in the first absorption circuit.

[0048] The first switch module is controlled by a first control terminal, which is connected to the first switch module and configured to control the first switch module according to the received instructions from the host computer.

[0049] The second switching module includes: a second switching circuit, a second absorption circuit, a second pre-charge circuit, and a second discharge circuit; the second switching circuit is configured to be turned on or off according to a command received from a second control terminal, and the second switching circuit includes at least two switching units connected in anti-parallel; the switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current, and the switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series; at least two switching units are connected in anti-parallel to form the second switching circuit;

[0050] The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switch circuit. The second pre-charge circuit is configured to limit the current at the moment the second switch module is connected and to pre-charge the second absorption circuit. The second pre-charge circuit includes: a second pre-charge resistor and a second switch, with the second pre-charge resistor connected in parallel with the second switch.

[0051] The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charge circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least two sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor.

[0052] The second discharge circuit is electrically connected to the second switching circuit through the second absorption circuit, and the second discharge circuit is configured to release the energy stored in the second absorption circuit.

[0053] The second switch module is controlled by a second control terminal, which is connected to the second switch module and configured to control the second switch module according to the received instructions from the host computer.

[0054] The third switching module includes: a third switching circuit, a third absorption circuit, a third pre-charge circuit, and a third discharge circuit;

[0055] The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit.

[0056] The third pre-charging circuit is connected in series with the third absorption circuit and then in parallel with the third switching circuit. The third pre-charging circuit is configured to limit the current at the moment the third switching module is connected and to pre-charge the third absorption circuit. The third pre-charging circuit includes: a third pre-charging resistor and a third switch, with the third pre-charging resistor and the third switch connected in parallel.

[0057] The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charge circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, with the third absorption unit electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least two sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor.

[0058] The third discharge circuit is electrically connected to the third switching circuit through the third absorption circuit, and the third discharge circuit is configured to release the energy stored in the third absorption circuit.

[0059] The third switch module is controlled by a third control terminal, which is connected to the third switch module and configured to control the third switch module according to received instructions from the host computer. When the first discharge circuit, the second discharge circuit, and the third discharge circuit are the same discharge circuit, the second switch module is connected to the third and fourth nodes of the first switch module through the second and seventh nodes of the discharge circuit. Both the second and third switch modules share the discharge circuit with the first switch module through the third and fourth nodes of the discharge circuit.

[0060] According to another aspect of this disclosure, a third aspect of this disclosure provides a power transmission device that utilizes a switching module of any one of the first or second aspects, the power transmission device comprising:

[0061] At least two switch modules are installed in the power transmission lines with two power supplies and are connected to the power grid.

[0062] The switching module disclosed herein adopts an innovative topology circuit structure, realizing millisecond-level fast response switching, and uses standardized power devices to reduce the overall cost of the switching module and save manufacturing costs; using the switching module disclosed herein can reduce the power loss of the switching process in the circuit, and the switching module itself has low power consumption.

[0063] It should be understood that the description in the Summary of the Invention section is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of this disclosure will become readily apparent from the following description. Attached Figure Description

[0064] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. The drawings are provided for a better understanding of the invention and are not intended to limit the scope of this disclosure. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0065] Figure 1 is a circuit diagram of an existing AC electronic switch using thyristors;

[0066] Figure 2 is a circuit diagram of an existing AC electronic switch;

[0067] Figure 3 shows another existing AC electronic switch circuit diagram;

[0068] Figure 4 shows a schematic block diagram of a switch module according to an embodiment of the present disclosure;

[0069] Figure 5 shows a schematic block diagram of a switch module according to another embodiment of the present disclosure;

[0070] Figure 6 shows a circuit diagram of a switching module according to an embodiment of the present disclosure;

[0071] Figure 7 shows a circuit diagram indicating the component symbols in the switch module according to an embodiment of the present disclosure;

[0072] Figure 8 shows a circuit diagram of a switching module according to another embodiment of the present disclosure;

[0073] Figure 9 shows a schematic diagram of a three-phase four-wire circuit using a switching module according to an embodiment of the present disclosure, sharing a first discharge circuit;

[0074] Figure 10 shows a schematic diagram of a three-phase four-wire circuit of an application switching module in an embodiment of this disclosure that does not share a first discharge circuit;

[0075] Figure 11 shows a schematic diagram of a three-phase three-wire circuit using a switching module that shares a first discharge circuit according to an embodiment of the present disclosure. Detailed Implementation

[0076] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0077] Unless otherwise defined, all terms used herein (including technical and scientific terms) shall have the same meaning as commonly understood by one of ordinary skill in the art to which this subject matter pertains. It will be further understood that terms such as those defined in commonly used dictionaries shall be interpreted as having the meaning consistent with their meaning in the context of the specification and in the relevant art, and shall not be interpreted in an idealized or overly formal form unless otherwise explicitly defined herein. As used herein, the statement of “connecting” or “coupling” two or more parts together shall mean that these parts are directly joined together or joined through one or more intermediate components.

[0078] For ease of description, spatial relative terms such as “up,” “down,” “left,” “right,” “top,” and “bottom” are used herein to describe the spatial positional relationship of a device or element to other devices or elements, as shown in the figures. For example, the terms “on,” “above,” “above,” “on the upper surface,” “above,” “positioned on,” or “positioned on top of” mean that a first element, such as a first structure, exists on a second element, such as a second structure, wherein, in some embodiments, an intermediate element exists between the first and second elements, and in some embodiments, no intermediate element exists. The term “contact” means connecting a first element, such as a first structure, and a second element, such as a second structure, with or without other elements at the interface between the two elements. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation of the device as described in the figures. For example, if a device in the figures is inverted, a device described as “above” or “on top of” other devices or structures will subsequently be positioned “below” or “under” other devices or structures. Therefore, the exemplary term "above" in some embodiments includes both "above" and "below". The device may be positioned in other different ways, rotated 90 degrees, or in other orientations, and the spatial relative descriptions used herein are interpreted accordingly.

[0079] AC electronic switches, also known as solid-state electronic switches, can control the switching of AC current. They are often implemented using thyristors connected in parallel, as shown in Figure 1. AC electronic switches can be easily controlled by low-voltage signals, such as using an MCU, making them very convenient for various applications and showing great promise.

[0080] Solid-state switches constructed using anti-parallel thyristors have the advantages of high voltage and high current, but they cannot be turned off by weak electrical signals. Therefore, their use is greatly limited in applications requiring rapid turn-off.

[0081] As shown in Figure 2, the prior art is an IGBT-based electronic switch that can quickly achieve bidirectional current interruption and conduction. However, each switch requires two capacitors and two discharge resistors. If it is used to form a multi-channel switch (such as a commonly used three-phase switch), it requires twice the number of capacitors and resistors as the switches. Therefore, the number of components is large, the cost is high, and the switch midpoint needs to be led out, making the circuit complex and affecting the reliability of the device. In addition, the capacitor voltage is uncontrollable. When the switch is in the conducting state, the capacitor gradually discharges to zero voltage. When the switch is turned off again, the main circuit current will continue to flow through the capacitor, charging the capacitor from zero voltage. Therefore, the turn-off time of this disclosed technology is relatively long and cannot achieve rapid turn-off.

[0082] As shown in Figure 3, in the prior art, when a fault such as overcurrent or short circuit occurs and the switch needs to be turned off, the RC absorption circuit is difficult to completely absorb the induced voltage. Therefore, it is necessary to add MOV devices such as varistors. However, such surge protection devices have low reliability and will fail under large impact energy or multiple impacts, resulting in a decrease in the life and reliability of the device.

[0083] Therefore, AC electronic switches in related technologies suffer from technical problems such as complex circuit structure, high cost, low reliability, and slow response speed.

[0084] To address the aforementioned technical problems, the AC electronic switch module provided in this disclosure simplifies the circuit structure, reduces costs, improves reliability, and achieves a faster response speed.

[0085] Figure 4 is a schematic block diagram of a switch module provided in an embodiment of the present disclosure. In some embodiments, the switch module is applied in a single-phase AC transmission line and is configured to open or close the AC current path between input port A and output port B. The switch module is controlled by a first control terminal connected to the switch module and configured to control the switch module according to the received host computer instructions.

[0086] Figure 5 is a schematic block diagram of a switch module provided in another embodiment of this disclosure, wherein A is an input port, B is an output port, Line represents the grid input terminal, power input terminal or distribution terminal, i.e. a 0.4kV transmission line, Load represents the load, N is the grid neutral line or power neutral line, and the first control terminal is configured to control the various circuits in the switch module; the switch module includes: a first switching circuit, a first absorption circuit, a first pre-charge circuit and a first discharge circuit;

[0087] Figure 6 is a circuit diagram of a switch module provided in an embodiment of the present disclosure, applied in a single-phase AC transmission line. Figure 7 is a circuit diagram of the switch module shown in Figure 6, indicating the component symbols, provided in an embodiment of the present disclosure. Wherein, N is the neutral wire of the power grid, and L is the live wire of the power grid. The first switch circuit is configured to turn on or off according to a command received from a first control terminal. The first switch circuit includes at least two switch units connected in reverse parallel. The switch unit is connected to the power grid input terminal and configured to turn on or off bidirectional current. The switch unit includes at least one semiconductor switch device and a diode, with the semiconductor switch device and diode connected in series. At least two switch units are connected in reverse parallel to form the first switch circuit. The semiconductor switch devices in the switch module are connected in reverse series, and the two ends of the switch unit are connected to the input terminal and the output terminal, thus at least two switch units are connected in reverse parallel to form the first switch circuit.

[0088] The first pre-charge circuit is connected in series with the first absorption circuit and then in parallel with the first switching circuit. The first pre-charge circuit is configured to limit the current at the moment the first absorption circuit is connected and to pre-charge the first absorption circuit. The first pre-charge circuit includes a first pre-charge resistor R1 and a first switch S1, which are connected in parallel. When the first absorption circuit is connected, the first switch is open, and the first pre-charge resistor limits the current at the moment the first absorption circuit is connected. This disclosure adopts an innovative topology circuit structure, connecting the first pre-charge circuit and the first absorption circuit in series and then in parallel with the first switching circuit, integrating them into a standardized power device, simplifying the circuit structure, and reducing the overall cost of the switching module by using standardized power devices, thus saving manufacturing costs.

[0089] The first absorption circuit is configured to absorb the electrical energy generated when the first pre-charging circuit and the first switching circuit are working. The first absorption circuit includes: a first rectifier unit and a first absorption unit, the first absorption unit being electrically connected to the first rectifier unit; the first rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the first rectifier unit including at least three sets of diodes connected in series; the first absorption unit is configured to absorb the electrical energy generated during the turn-off process of the first switching circuit, the first absorption unit including at least one capacitor.

[0090] In Figure 7, the first absorption circuit and the first switching circuit are connected in parallel through the first pre-charging circuit. The first absorption unit includes at least one capacitor C. The first rectifier unit includes three sets of diodes connected in series in pairs. From top to bottom and from left to right, they are the third diode D3, the fourth diode D4, the fifth diode D5, the sixth diode D6, the seventh diode D7, and the eighth diode D8. The third diode D3 and the fourth diode D4 form one set, the fifth diode D5 and the sixth diode D6 form one set, and the seventh diode D7 and the eighth diode D8 form one set.

[0091] The first discharge circuit is electrically connected to the first switching circuit through the first absorption circuit, and the first discharge circuit is configured to release the energy stored in the first absorption circuit.

[0092] The switch module is controlled by a first control terminal, which is connected to the switch module and configured to control the switch module according to received instructions from a host computer.

[0093] The switching module provided in this disclosure adopts an innovative topology circuit structure, achieving a fast response switching speed in milliseconds. The use of standardized power devices makes the overall cost of the switching module lower, saving manufacturing costs, and the switching module itself has low energy consumption.

[0094] In some embodiments of this disclosure, the first switching circuit includes at least a first switching unit and a second switching unit;

[0095] The first switching unit includes at least a first semiconductor switching device and a first diode. The drain and source of the first semiconductor switching device are respectively connected to the power grid input terminal and the positive terminal of the first diode, and the negative terminal of the first diode is connected to the load.

[0096] The second switching unit includes at least a second semiconductor switching device and a second diode. The source and drain of the second semiconductor switching device are connected to the power grid input terminal and the negative terminal of the second diode, respectively, and the positive terminal of the second diode is connected to the load. It should be noted that the embodiments of this disclosure do not limit the number of the first semiconductor switching device and the second semiconductor switching device.

[0097] In Figure 7, the first switching circuit is divided into two anti-parallel switching units. The upper first switching unit consists of a first semiconductor switching device Q1 and a first diode D1, and the lower second switching unit consists of a second semiconductor switching device Q2 and a second diode D2. The first semiconductor switching device Q1 has a controllable part that can receive commands and an uncontrollable part. The uncontrollable part can be a diode.

[0098] In some embodiments of this disclosure, the semiconductor switching device is a reverse-conducting power semiconductor device. The semiconductor switching device is any one of an IGBT, a MOSFET, or an IGCT.

[0099] In some embodiments of this disclosure, in the first absorption circuit, the first rectifier unit and the first absorption unit are connected in series.

[0100] In the first rectifier unit, diodes connected in series in pairs are connected in forward direction in each group; the groups of diodes connected in series in pairs are connected in parallel and in parallel with the capacitor.

[0101] In some embodiments of this disclosure, in the first absorption circuit:

[0102] The input and output terminals of the first switching circuit are electrically connected to the midpoints of the series-connected diodes of each group in the first rectifier unit, respectively.

[0103] The first rectifier unit is connected to the neutral wire of the power grid.

[0104] In some embodiments of this disclosure, the first discharge circuit includes:

[0105] At least one discharge resistor,

[0106] A semiconductor switching transistor or mechanical switch is connected in series with a discharge resistor;

[0107] One end of the first discharge circuit is connected to the ground wire.

[0108] In Figure 7, the first discharge circuit and the first absorption circuit are connected in parallel. The first discharge circuit includes a discharge resistor R2 and a semiconductor switch Q3, wherein the discharge resistor R2 and the semiconductor switch Q3 are connected in series, and the semiconductor switch Q3 is any one of IGBT, MOSFET or IGCT.

[0109] The working principle of the switch module shown in Figure 7 in a single-phase AC transmission line is described below.

[0110] In the initial state, when the switch module is first connected to the circuit, the first switch S1 in the first pre-charging circuit is in the open state. In order to prevent current surges from damaging electronic components, the first pre-charging resistor R1 can limit the current. At the same time, the first pre-charging resistor R1 can also pre-charge the capacitor C. The rated voltage of the capacitor C is a fixed value, which includes 450V, 680V or 1kV, etc. Those skilled in the art can select the appropriate value according to actual needs.

[0111] Taking a capacitor C with a rated voltage of 450V as an example, at the moment the switching module is connected to the power transmission line, the current surge in the circuit may charge the capacitor C to about 300V in some embodiments. When the switching module is working normally, the first switch S1 is closed, and the capacitor C, which can store electrical energy, absorbs the electrical energy in the circuit inductance during the switching module's turn-off process, which can continuously push the capacitor voltage from about 300V. When the capacitor voltage exceeds 430V (this value is set according to needs, and since a rated voltage of 450V is used as an example, it is more appropriate to set this value to 430V), the semiconductor switch Q3 in the first discharge circuit starts to operate, slowly and steadily releasing the electrical energy exceeding 430V, so that the voltage of the capacitor C is maintained near the preset voltage.

[0112] It should be noted that in some embodiments, the control method of capacitor C is as follows: when the voltage difference fluctuation of capacitor C exceeds a fixed value, the semiconductor switch Q3 is activated to release the electrical energy of capacitor C, that is, capacitor C discharges through discharge resistor R2, and the DC terminal voltage of capacitor C decreases, so that the voltage of capacitor C meets the requirements; furthermore, if the voltage difference of capacitor C is set to 20V (assuming the preset voltage is 420V, then the voltage difference is set to 20V), that is, when the voltage of capacitor C is 440V, the semiconductor switch Q3 is activated to release the electrical energy of capacitor C, so that the operating voltage of capacitor C drops to 420V, which meets the requirements.

[0113] The switching module provided in this embodiment is applied in an AC circuit. Under the action of positive and negative currents, the two switching units in the first switching circuit are alternately turned on or off. For the first semiconductor switching device Q1 of the first switching unit, when the switching module is connected to the power grid input terminal, the positive current flows through the first semiconductor switching device Q1, through the fifth diode D5 in the first absorption circuit, and is rectified by the fifth diode D5 and flows through the positive terminal of the capacitor C. It then flows through the negative terminal of the capacitor C and through the eighth diode D8, and is then output from the B terminal of the switching module to form a loop.

[0114] When the switching module is connected to the mains input terminal, the negative current flows through the second semiconductor switching device Q2 and the second diode D2, and then through the seventh diode D7 in the first absorption circuit. The negative current is rectified by the seventh diode D7 and flows through the positive terminal of the capacitor C. It then flows through the negative terminal of the capacitor C and through the sixth diode D6, and is then output from the A terminal of the switching module, forming a loop.

[0115] When the first switching circuit is not working, when the switching module is connected to the mains input terminal, the current flows through the seventh diode D7 in the first absorption circuit, is rectified, flows through the positive terminal of capacitor C, flows through the negative terminal of capacitor C, flows through the sixth diode D6, and is then output from the N line of the switching module, forming a loop.

[0116] Figure 8 is a circuit diagram of a switching module provided in another embodiment of this disclosure. Compared with the switching module shown in Figure 7, the positions of the diodes and semiconductor switching devices in the switching unit shown in Figure 8 have changed. In Figure 8, the diodes are in front and the semiconductor switching devices are behind. The first switching unit located above is composed of a first diode D1 and a first semiconductor switching device Q1, and the second switching unit located below is composed of a second diode D2 and a second semiconductor switching device Q2. The role of each component in the circuit and the working principle of the switching module are the same as those in Figure 7, and will not be repeated here.

[0117] The switching module provided in this disclosure is applicable to three-phase three-wire or three-phase four-wire power supply scenarios in some embodiments. In some embodiments, it shares a first discharge circuit and a neutral (N) line, while in others, it does not share a first discharge circuit or a neutral (N) line. Three-phase three-wire refers to the voltage drop from a 10kV substation to a 0.4kV transformer during power transmission and distribution. Each of the three phases has three wires, and in practical applications, each wire corresponds to a different color. A neutral line can be added to the three-wire configuration to obtain a three-phase four-wire configuration. This neutral line is the zero line, i.e., the N line in this disclosure. It should be noted that this disclosure is for illustrative purposes only and does not constitute a limitation on the technical solution of this disclosure. The switching module provided in this disclosure can also be applied to three-phase five-wire power supply scenarios (by adding a ground wire to a three-phase four-wire configuration).

[0118] Figure 9 is a schematic diagram of a three-phase four-wire switch module with a shared first discharge circuit and a shared N line provided in an embodiment of this disclosure. The N line is the neutral line of the power grid, and the L1, L2, and L3 lines are the three-phase lines of the power grid, respectively. Under the transformer, any one phase line and the neutral line are taken to form the 220V voltage in the power supply line for use by general residential users. That is, in the 220V usage scenario, there are two lines, one is the live line and the other is the neutral line.

[0119] In Figure 9, the switching module also includes: a second switching circuit, a second absorption circuit, a second pre-charging circuit, a third switching circuit, a third absorption circuit, and a third pre-charging circuit;

[0120] The second switching circuit is configured to turn on or off according to the command received from the second control terminal. The second switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the second switching circuit.

[0121] The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switch circuit. The second pre-charge circuit is configured to limit the current at the moment the second absorption circuit is connected and to pre-charge the second absorption circuit. The second pre-charge circuit includes a second pre-charge resistor and a second switch, with the second pre-charge resistor connected in parallel with the second switch. Before connection, the second switch in the second pre-charge circuit is turned off, and the second pre-charge resistor is connected to the circuit to limit the current at the moment the second absorption circuit is connected, thereby protecting the second absorption circuit.

[0122] The second absorption circuit is configured to absorb the electrical energy generated during the operation of the second pre-charge circuit and the second switching circuit. The second absorption circuit includes a second rectifier unit and a second absorption unit, with the second absorption unit electrically connected to the second rectifier unit. The second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and includes at least three sets of diodes connected in series. The second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, and includes at least one capacitor. This disclosure adopts an innovative topology circuit structure, connecting the second pre-charge circuit and the second absorption circuit in series and then connecting them in parallel with the second switching circuit to integrate them into a standardized power device. The standardized power device reduces the overall cost of the switching module and saves manufacturing costs.

[0123] The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit.

[0124] The third pre-charge circuit is connected in series with the third absorption circuit and then in parallel with the third switching circuit. The third pre-charge circuit is configured to limit the current of the third absorption circuit at the moment of connection and to pre-charge the third absorption circuit. The third pre-charge circuit includes a third pre-charge resistor and a third switch, with the third pre-charge resistor connected in parallel with the third switch. Before connection, the third switch in the third pre-charge circuit is turned off, and the third pre-charge resistor is connected to the circuit to limit the current of the third absorption circuit at the moment of connection, thereby protecting the third absorption circuit. This disclosure adopts an innovative topology circuit structure, connecting the third pre-charge circuit and the third absorption circuit in series and then in parallel with the third switching circuit, integrating them into a standardized power device. The standardized power device reduces the overall cost of the switching module and saves manufacturing costs.

[0125] The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charging circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, with the third absorption unit electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least three sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor.

[0126] One end of the second absorption circuit is connected to the neutral wire of the power grid through the fifth node N5 and the first node N1. One end of the third absorption circuit is connected to the neutral wire of the power grid through the sixth node N6 and the first node N1. This connection between nodes allows the three phases to share the neutral wire (N line), thus resolving the three-phase imbalance problem. The other end of the second absorption circuit is electrically connected to the third node N3 and the fourth node N4 of the first discharge circuit through the second node N2 and the seventh node N7. The other end of the third absorption circuit is electrically connected to the third node N3 and the fourth node N4 of the first discharge circuit through the ninth node N9 and the eighth node N8. This connection between nodes allows the three phases to share the first discharge circuit, ensuring balanced charging and discharging of each phase in the three-phase circuit, achieving unified charging and discharging of the capacitor.

[0127] In the switch module shown in Figure 9, R2 and Q3 are connected in series to form the first discharge circuit. Furthermore, the functions and roles of the following components in the circuit are equivalent: Q1 is equivalent to Q1' and Q1”; Q2 is equivalent to Q2' and Q2”; D1 is equivalent to D1' and D1”; D2 is equivalent to D2' and D2”; D3 is equivalent to D3' and D3”; D4 is equivalent to D4' and D4”; D5 is equivalent to D5' and D5”; D6 is equivalent to D6' and D6”; D7 is equivalent to D7' and D7”; D8 is equivalent to D8' and D8”; R1 is equivalent to R1' and R1”; S1 is equivalent to S1' and S1”; C is equivalent to C' and C”.

[0128] In the switching module provided in this embodiment, the three phases share a first discharge circuit and a common N line. In some embodiments, the first control terminal, the second control terminal, and the third control terminal are the same control terminal, while in some embodiments, the first control terminal, the second control terminal, and the third control terminal are different control terminals.

[0129] Figure 10 is a schematic diagram of a three-phase four-wire switch module that shares a common N-line but does not share a first discharge circuit, according to an embodiment of this disclosure. The switch module further includes: a second switch circuit, a second absorption circuit, a second pre-charge circuit, a second discharge circuit, a third switch circuit, a third absorption circuit, a third pre-charge circuit, and a third discharge circuit. The second switch circuit is configured to turn on or off according to a command received from a second control terminal. The second switch circuit includes at least two switch units connected in anti-parallel. Each switch unit is connected to the grid input terminal and configured to turn on or off bidirectional current. Each switch unit includes at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switch units are connected in anti-parallel to form the second switch circuit.

[0130] The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switching circuit. The second pre-charge circuit is configured to limit the current of the second absorption circuit at the moment of connection and pre-charge the second absorption circuit. The second pre-charge circuit includes a second pre-charge resistor and a second switch, with the second pre-charge resistor connected in parallel with the second switch. This disclosure adopts an innovative topology circuit structure, connecting the second pre-charge circuit and the second absorption circuit in series and then in parallel with the second switching circuit, integrating them into a standardized power device. The standardized power device reduces the overall cost of the switching module and saves manufacturing costs.

[0131] The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charge circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least three sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor.

[0132] The second discharge circuit is electrically connected to the second switching circuit through the second absorption circuit, and the second discharge circuit is configured to release the energy stored in the second absorption circuit.

[0133] The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit.

[0134] The third pre-charge circuit is connected in series with the third absorption circuit and then in parallel with the third switching circuit. The third pre-charge circuit is configured to limit the current of the third absorption circuit at the moment of connection and pre-charge the third absorption circuit. The third pre-charge circuit includes a third pre-charge resistor and a third switch, with the third pre-charge resistor and the third switch connected in parallel. This disclosure adopts an innovative topology circuit structure, connecting the third pre-charge circuit and the third absorption circuit in series and then in parallel with the third switching circuit, integrating them into a standardized power device. The standardized power device makes the overall cost of the switching module lower and saves manufacturing costs.

[0135] The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charging circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, with the third absorption unit electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least three sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor.

[0136] The third discharge circuit is electrically connected to the third switching circuit via the third absorption circuit. The third discharge circuit is configured to release the energy stored in the second absorption circuit. The second absorption circuit is connected to the neutral wire of the power grid via the fifth node N5 and the first node N1, and the third absorption circuit is connected to the neutral wire of the power grid via the sixth node N6 and the first node N1. The first absorption circuit is connected to the neutral wire of the power grid via the first node N1. Each absorption circuit is connected to the neutral wire of the power grid via a node, so that the three phases share the N line. The three-phase imbalance problem is solved by the connection method of sharing the N line.

[0137] In the switch module shown in Figure 10, R2' and Q3' are connected in series to form the first discharge circuit, R2" and Q3" are connected in series to form the second discharge circuit, and R2" and Q3" are connected in series to form the third discharge circuit. L1, L2, and L3 represent the first, second, and third phases, respectively. The three phases of the three-phase AC power are the first, second, and third phases, respectively. Their voltage waveforms are sinusoidal waves with a phase difference of 120 degrees. There is a potential difference between the first, second, and third phases. Current flows from the phase with the highest potential to the phase with the lowest potential. Thus, when any phase is selected as a single phase, any one of the other two phases can be used as part of a single-phase circuit. L1, L2, and L3 are discharged by their respective discharge circuits, making the discharge of each phase more targeted and further adjusting the three-phase imbalance.

[0138] The following components in Figure 10 have the same function and role in the circuit:

[0139] Q1 is equivalent to Q1' and Q1”; Q2 is equivalent to Q2' and Q2”; D1 is equivalent to D1' and D1”; D2 is equivalent to D2' and D2”; D3 is equivalent to D3' and D3”; D4 is equivalent to D4' and D4”; D5 is equivalent to D5' and D5”; D6 is equivalent to D6' and D6”; D7 is equivalent to D7' and D7”; D8 is equivalent to D8' and D8”; R1 is equivalent to R1' and R1”; S1 is equivalent to S1' and S1”; C is equivalent to C' and C”.

[0140] In the switching module provided in this embodiment, the three phases share the N line and do not share the first discharge circuit. In one embodiment, the first control terminal, the second control terminal, and the third control terminal are the same control terminal. In another embodiment, the first control terminal, the second control terminal, and the third control terminal are different control terminals.

[0141] Figure 11 is a schematic diagram of a three-phase three-wire switch module that shares a first discharge circuit but does not share a N line, provided in an embodiment of this disclosure. The switch module includes, from top to bottom, a first switch module, a second switch module, and a third switch module.

[0142] The first switching module includes: a first switching circuit, a first absorption circuit, a first pre-charge circuit, and a first discharge circuit; the first switching circuit is configured to turn on or off according to a command received from a first control terminal, and the first switching circuit includes at least two switching units connected in anti-parallel; the switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current; the switching unit includes at least one semiconductor switching device and a diode, the semiconductor switching device and the diode being connected in series; at least two switching units are connected in anti-parallel to form the first switching circuit;

[0143] The first pre-charging circuit is connected in series with the first absorption circuit and then in parallel with the first switching circuit. The first pre-charging circuit is configured to limit the current at the moment the first switching module is connected and to pre-charge the first absorption circuit. The first pre-charging circuit includes: a first pre-charging resistor and a first switch, with the first pre-charging resistor connected in parallel with the first switch.

[0144] The first absorption circuit is configured to absorb the electrical energy generated when the first pre-charging circuit and the first switching circuit are working. The first absorption circuit includes: a first rectifier unit and a first absorption unit, the first absorption unit being electrically connected to the first rectifier unit; the first rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the first rectifier unit including at least two sets of diodes connected in series; the first absorption unit is configured to absorb the electrical energy generated during the turn-off process of the first switching circuit, the first absorption unit including at least one capacitor.

[0145] The first discharge circuit is electrically connected to the first switching circuit through the first absorption circuit, and the first discharge circuit is configured to release the energy stored in the first absorption circuit.

[0146] The first switch module is controlled by a first control terminal, which is connected to the first switch module and configured to control the first switch module according to the received instructions from the host computer.

[0147] The second switching module includes: a second switching circuit, a second absorption circuit, a second pre-charge circuit, and a second discharge circuit; the second switching circuit is configured to be turned on or off according to a command received from a second control terminal, and the second switching circuit includes at least two switching units connected in anti-parallel; the switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current, and the switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series; at least two switching units are connected in anti-parallel to form the second switching circuit;

[0148] The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switch circuit. The second pre-charge circuit is configured to limit the current at the moment the second switch module is connected and to pre-charge the second absorption circuit. The second pre-charge circuit includes: a second pre-charge resistor and a second switch, with the second pre-charge resistor connected in parallel with the second switch.

[0149] The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charge circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least two sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor.

[0150] The second discharge circuit is electrically connected to the second switching circuit through the second absorption circuit, and the second discharge circuit is configured to release the energy stored in the second absorption circuit.

[0151] The second switch module is controlled by a second control terminal, which is connected to the second switch module and configured to control the second switch module according to the received instructions from the host computer.

[0152] The third switching module includes: a third switching circuit, a third absorption circuit, a third pre-charge circuit, and a third discharge circuit; the third switching circuit is configured to be turned on or off according to the command received from the third control terminal, and the third switching circuit includes at least two switching units connected in anti-parallel; the switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current, and the switching units include at least one semiconductor switching device and a diode, the semiconductor switching device and the diode being connected in series; at least two switching units are connected in anti-parallel to form the third switching circuit;

[0153] The third pre-charging circuit is connected in series with the third absorption circuit and then in parallel with the third switching circuit. The third pre-charging circuit is configured to limit the current at the moment the third switching module is connected and to pre-charge the third absorption circuit. The third pre-charging circuit includes: a third pre-charging resistor and a third switch, with the third pre-charging resistor and the third switch connected in parallel.

[0154] The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charge circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, with the third absorption unit electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least two sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor.

[0155] The third discharge circuit is electrically connected to the third switching circuit through the third absorption circuit, and the third discharge circuit is configured to release the energy stored in the third absorption circuit.

[0156] The third switch module is controlled by a third control terminal, which is connected to the third switch module and configured to control the third switch module according to the received instructions from the host computer.

[0157] When the first, second, and third discharge circuits are the same discharge circuit, the second switching module is connected to the first switching module's third node N3 and fourth node N4 via the second node N2 and the seventh node N7. Both the second and third switching modules share the discharge circuit with the first switching module via the third node N3 and the fourth node N4. Each module is connected to the discharge circuit through corresponding nodes, sharing the third node N3 and the fourth node N4. This shared discharge circuit ensures balanced charging and discharging of each phase in the three-phase circuit, achieving unified charging and discharging of the capacitor.

[0158] In some embodiments, the first discharge circuit, the second discharge circuit, and the third discharge circuit are the same discharge circuit. In some embodiments, the first discharge circuit, the second discharge circuit, and the third discharge circuit are not the same discharge circuit. The switching module shown in FIG11 is the case where the first discharge circuit, the second discharge circuit, and the third discharge circuit are the same discharge circuit. In this case, the three phases share the first discharge circuit.

[0159] In Figure 11, L1, L2, and L3 represent the first, second, and third phases, respectively. The three phases of the three-phase alternating current are the first, second, and third phases, respectively. Their voltage waveforms are sinusoidal waves, and their phases differ by 120 degrees. There is a potential difference between the first, second, and third phases. Current flows from the phase with the highest potential to the phase with the lowest potential. Thus, when any one phase is selected as a single phase, any one of the other two phases can be used as part of a single-phase circuit.

[0160] The following components in Figure 11 have the same function and role in the circuit:

[0161] Q1 is equivalent to Q1' and Q1”; Q2 is equivalent to Q2' and Q2”; D1 is equivalent to D1' and D1”; D2 is equivalent to D2' and D2”; D3 is equivalent to D3' and D3”; D4 is equivalent to D4' and D4”; D5 is equivalent to D5' and D5”; D6 is equivalent to D6' and D6”; D7 is equivalent to D7' and D7”; D8 is equivalent to D8' and D8”; R1 is equivalent to R1' and R1”; S1 is equivalent to S1' and S1”; C is equivalent to C' and C”.

[0162] In the switching module provided in this embodiment, the three phases share the first discharge circuit and do not share the N line; in some embodiments, the first control terminal, the second control terminal and the third control terminal are the same control terminal, and each phase switching module is controlled uniformly through one control terminal; in some embodiments, the first control terminal, the second control terminal and the third control terminal are different control terminals, and each phase switching module is controlled separately through different control terminals.

[0163] Using the switching module provided in this disclosure in three-phase or single-phase transmission lines can reduce the power loss during the switching process in the line and reduce the energy consumption of the switching module itself.

[0164] This disclosure also provides a power transmission device that utilizes a switching module employing any one of the above-described embodiments, the power transmission device comprising:

[0165] At least two switch modules are installed in the power transmission lines with two power supplies and are connected to the power grid.

[0166] The three-phase switch module provided in this disclosure can be applied to power transmission scenarios or transmission lines with two power supplies. When the load of one of the three-phase switch modules fails and needs to be repaired and the power supply to that line is cut off, the three-phase switch module in this disclosure can be used to quickly switch and start any one of the other two lines without affecting the normal operation of other loads in that line.

[0167] In power transmission and consumption scenarios with two power supplies, the switching module provided in this embodiment can achieve millisecond-level rapid switching to another power transmission line, so that equipment that requires uninterrupted power supply can also operate normally while the other line is under maintenance, reducing user losses.

[0168] As can be seen from the above description, the embodiments of this disclosure achieve the following technical effects:

[0169] The switching module disclosed herein adopts an innovative topology circuit structure, achieving millisecond-level fast response switching;

[0170] Using standardized power devices makes the overall cost of the switching module lower, saving manufacturing costs;

[0171] Using the switching module provided in this disclosure in three-phase or single-phase transmission lines can reduce the power loss during the switching process in the line and reduce the energy consumption of the switching module itself.

[0172] In power transmission and consumption scenarios with two power supplies, the switching module provided in this embodiment can achieve millisecond-level rapid switching to another power transmission line, so that equipment requiring uninterrupted power supply can also operate normally while the other line is under maintenance, reducing user losses.

[0173] The specific embodiments described above do not constitute a limitation on the scope of protection of this disclosure. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A switching module, comprising: The circuit comprises a first switching circuit, a first absorption circuit, a first pre-charging circuit, and a first discharging circuit; The first switching circuit is configured to turn on or off according to the instruction received from the first control terminal. The first switching circuit includes at least two switching units connected in reverse parallel. The switching unit is connected to the power grid input and is configured to turn on or off bidirectional current. The switching unit includes at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form a first switching circuit. The first pre-charging circuit is connected in series with the first absorption circuit and then in parallel with the first switching circuit. The first pre-charging circuit is configured to limit the current of the first absorption circuit at the moment of connection and to pre-charge the first absorption circuit. The first pre-charge circuit includes: a first pre-charge resistor and a first switch, wherein the first pre-charge resistor and the first switch are connected in parallel; The first absorption circuit is configured to absorb the electrical energy generated when the first pre-charging circuit and the first switching circuit are operating. The first absorption circuit includes a first rectifier unit and a first absorption unit, wherein the first absorption unit is electrically connected to the first rectifier unit. The first rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the first rectifier unit includes at least three sets of diodes connected in series. The first absorption unit is configured to absorb the electrical energy generated during the turn-off process of the first switching circuit, and the first absorption unit includes at least one capacitor. The first discharge circuit is electrically connected to the first switching circuit through the first absorption circuit, and the first discharge circuit is configured to release the energy stored in the first absorption circuit. The switch module is controlled by a first control terminal, which is connected to the switch module and configured to control the switch module according to received instructions from a host computer.

2. The switch module according to claim 1, wherein, The first switching circuit includes at least a first switching unit and a second switching unit; The first switching unit includes at least a first semiconductor switching device and a first diode. The drain and source of the first semiconductor switching device are respectively connected to the power grid input terminal and the positive terminal of the first diode, and the negative terminal of the first diode is connected to the load. The second switching unit includes at least a second semiconductor switching device and a second diode. The source and drain of the second semiconductor switching device are respectively connected to the power grid input terminal and the negative terminal of the second diode, and the positive terminal of the second diode is connected to the load.

3. The switch module according to claim 1, wherein, The semiconductor switching device is a reverse-conducting power semiconductor device.

4. The switch module according to claim 1, characterized in that, In the first absorption circuit, the first rectifier unit is connected in series with the first absorption unit; In the first rectifier unit, the diodes connected in series in pairs are connected in forward direction in each group; the groups of diodes connected in series in pairs are connected in parallel and in parallel with the capacitor.

5. The switch module according to claim 1, wherein, In the first absorption circuit: The input and output terminals of the first switching circuit are electrically connected to the midpoints of the series-connected diodes of the first rectifier unit, respectively. The first rectifier unit is electrically connected to the neutral wire of the power grid.

6. The switch module according to any one of claims 1 to 3, wherein, The first discharge circuit includes: At least one discharge resistor, A semiconductor switching transistor or mechanical switch is connected in series with a discharge resistor; One end of the first discharge circuit is connected to the ground wire.

7. The switch module according to claim 1, wherein, The switching module further includes: a second switching circuit, a second absorption circuit, a second pre-charging circuit, a third switching circuit, a third absorption circuit, and a third pre-charging circuit; The second switching circuit is configured to turn on or off according to the command received from the second control terminal. The second switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the second switching circuit. The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switching circuit. The second pre-charge circuit is configured to limit the current of the second absorption circuit at the moment of connection and to pre-charge the second absorption circuit. The second pre-charge circuit includes: a second pre-charge resistor and a second switch, wherein the second pre-charge resistor is connected in parallel with the second switch. The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charging circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least three sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor. The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit. The third pre-charging circuit is connected in series with the third absorption circuit and then in parallel with the third switching circuit. The third pre-charging circuit is configured to limit the current of the third absorption circuit at the moment of connection and to pre-charge the third absorption circuit. The third pre-charging circuit includes a third pre-charging resistor and a third switch, with the third pre-charging resistor connected in parallel with the third switch. The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charging circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, the third absorption unit being electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least three sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor. One end of the second absorption circuit is connected to the neutral wire of the power grid through the fifth node and the first node, and one end of the third absorption circuit is connected to the neutral wire of the power grid through the sixth node and the first node; The other end of the second absorption circuit is electrically connected to the third and fourth nodes of the first discharge circuit through the second and seventh nodes, and the other end of the third absorption circuit is electrically connected to the third and fourth nodes of the first discharge circuit through the ninth and eighth nodes.

8. The switch module according to claim 1, wherein, The switching module further includes: a second switching circuit, a second absorption circuit, a second pre-charge circuit, a second discharge circuit, a third switching circuit, a third absorption circuit, a third pre-charge circuit, and a third discharge circuit; The second switching circuit is configured to turn on or off according to the command received from the second control terminal. The second switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the second switching circuit. The second pre-charge circuit is connected in series with the second absorption circuit and then in parallel with the second switching circuit. The second pre-charge circuit is configured to limit the current of the second absorption circuit at the moment of connection and to pre-charge the second absorption circuit. The second pre-charge circuit includes: a second pre-charge resistor and a second switch, wherein the second pre-charge resistor is connected in parallel with the second switch. The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charging circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least three sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor. The second discharge circuit is electrically connected to the second switching circuit through the second absorption circuit, and the second discharge circuit is configured to release the energy stored in the second absorption circuit. The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit. The third pre-charging circuit is connected in series with the third absorption circuit and then in parallel with the third switching circuit. The third pre-charging circuit is configured to limit the current of the third absorption circuit at the moment of connection and to pre-charge the third absorption circuit. The third pre-charging circuit includes a third pre-charging resistor and a third switch, with the third pre-charging resistor connected in parallel with the third switch. The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charging circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, the third absorption unit being electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least three sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor. The third discharge circuit is electrically connected to the third switching circuit through the third absorption circuit, and the third discharge circuit is configured to release the energy stored in the second absorption circuit. The second absorption circuit is connected to the neutral wire of the power grid through the fifth node and the first node, and the third absorption circuit is connected to the neutral wire of the power grid through the sixth node and the first node.

9. A switch module, the switch module comprising: First switch module, second switch module, and third switch module; The first switching module includes: a first switching circuit, a first absorption circuit, a first pre-charge circuit, and a first discharge circuit; the first switching circuit is configured to turn on or off according to a command received from a first control terminal, the first switching circuit including at least two switching units connected in anti-parallel; the switching units are connected to the power grid input terminal and configured to turn on or off bidirectional current; the switching unit includes at least one semiconductor switching device and a diode, the semiconductor switching device and the diode being connected in series; at least two switching units are connected in anti-parallel to form the first switching circuit; The first pre-charging circuit is connected in series with the first absorption circuit and then in parallel with the first switching circuit. The first pre-charging circuit is configured to limit the current at the moment the first switching module is connected and to pre-charge the first absorption circuit. The first pre-charging circuit includes a first pre-charging resistor and a first switch, with the first pre-charging resistor connected in parallel with the first switch. The first absorption circuit is configured to absorb the electrical energy generated when the first pre-charging circuit and the first switching circuit are operating. The first absorption circuit includes a first rectifier unit and a first absorption unit, with the first absorption unit electrically connected to the first rectifier unit. The first rectifier unit is configured to rectify the current generated during the switching process of the switching unit and includes at least two sets of diodes connected in series. The first absorption unit is configured to absorb the electrical energy generated during the turn-off process of the first switching circuit and includes at least one capacitor. The first discharge circuit is electrically connected to the first switching circuit through the first absorption circuit, and the first discharge circuit is configured to release the energy stored in the first absorption circuit. The first switch module is controlled by a first control terminal, which is connected to the first switch module and configured to control the first switch module according to received instructions from a host computer. The second switching module includes: a second switching circuit, a second absorption circuit, a second pre-charge circuit, and a second discharge circuit; the second switching circuit is configured to turn on or off according to a command received from a second control terminal, and the second switching circuit includes at least two switching units connected in anti-parallel; the switching units are connected to the grid input terminal and are configured to turn on or off bidirectional current, and the switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series; at least two switching units are connected in anti-parallel to form the second switching circuit; The second pre-charging circuit is connected in series with the second absorption circuit and then in parallel with the second switching circuit. The second pre-charging circuit is configured to limit the current at the moment the second switching module is connected and to pre-charge the second absorption circuit. The second pre-charging circuit includes: a second pre-charging resistor and a second switch, wherein the second pre-charging resistor is connected in parallel with the second switch. The second absorption circuit is configured to absorb the electrical energy generated when the second pre-charging circuit and the second switching circuit are operating. The second absorption circuit includes: a second rectifier unit and a second absorption unit, the second absorption unit being electrically connected to the second rectifier unit; the second rectifier unit is configured to rectify the current generated during the switching process of the switching unit, the second rectifier unit including at least two sets of diodes connected in series; the second absorption unit is configured to absorb the electrical energy generated during the turn-off process of the second switching circuit, the second absorption unit including at least one capacitor. The second discharge circuit is electrically connected to the second switching circuit through the second absorption circuit, and the second discharge circuit is configured to release the energy stored in the second absorption circuit. The second switch module is controlled by a second control terminal, which is connected to the second switch module and configured to control the second switch module according to received instructions from the host computer. The third switching module includes: a third switching circuit, a third absorption circuit, a third pre-charge circuit, and a third discharge circuit; The third switching circuit is configured to turn on or off according to the instruction received from the third control terminal. The third switching circuit includes at least two switching units connected in anti-parallel. The switching units are connected to the power grid input terminal and are configured to turn on or off bidirectional current. The switching units include at least one semiconductor switching device and a diode, with the semiconductor switching device and the diode connected in series. At least two switching units are connected in anti-parallel to form the third switching circuit. The third pre-charging circuit is connected in series with the third absorption circuit and then in parallel with the third switching circuit. The third pre-charging circuit is configured to limit the current at the moment the third switching module is connected and to pre-charge the third absorption circuit. The third pre-charging circuit includes a third pre-charging resistor and a third switch, with the third pre-charging resistor connected in parallel with the third switch. The third absorption circuit is configured to absorb the electrical energy generated during the operation of the third pre-charging circuit and the third switching circuit. The third absorption circuit includes a third rectifier unit and a third absorption unit, the third absorption unit being electrically connected to the third rectifier unit. The third rectifier unit is configured to rectify the current generated during the switching process of the switching unit, and the third rectifier unit includes at least two sets of diodes connected in series. The third absorption unit is configured to absorb the electrical energy generated during the turn-off process of the third switching circuit, and the third absorption unit includes at least one capacitor. The third discharge circuit is electrically connected to the third switching circuit through the third absorption circuit, and the third discharge circuit is configured to release the energy stored in the third absorption circuit. The third switch module is controlled by a third control terminal, which is connected to the third switch module and configured to control the third switch module according to received instructions from the host computer. When the first discharge circuit, the second discharge circuit, and the third discharge circuit are the same discharge circuit, the second switch module is connected to the discharge circuit of the first switch module through the second node and the seventh node. Both the second switch module and the third switch module share the discharge circuit with the first switch module through the third node and the fourth node.

10. A power transmission device using the switching module of claim 1 or claim 9, the power transmission device comprising: At least two switch modules are installed in the power transmission lines with two power supplies and are connected to the power grid.

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