A high-voltage switch reluctance motor cascade control system
By connecting the drive bridge circuit in series and controlling its on/off state, combined with the isolation transformer and rectifier circuit, the problem of high-voltage output of switched reluctance motors is solved, enabling high-voltage output using switching transistors with lower withstand voltage ratings, reducing costs and improving system reliability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANDONG KEHUI POWER AUTOMATION
- Filing Date
- 2025-07-25
- Publication Date
- 2026-07-21
AI Technical Summary
In the existing technology, the switching transistors in the drive bridge circuit of the switched reluctance motor need to withstand a large power. High-voltage power devices have high production costs and their withstand voltage levels are limited by materials, making it difficult to achieve high-voltage output.
By connecting multiple drive bridge circuits in series and controlling the on/off state of each drive bridge circuit through the main control unit, combined with isolation transformers and rectifier circuits, cascade control of high-voltage switched reluctance motors is achieved using switching transistors with low withstand voltage ratings.
This invention enables high-voltage output of switched reluctance motors using switching transistors with lower withstand voltage ratings, reducing device costs and improving system reliability.
Smart Images
Figure CN224538082U_ABST
Abstract
Description
Technical Field
[0001] A cascaded control system for a high-voltage switched reluctance motor belongs to the field of switched reluctance motor control technology. Background Technology
[0002] Switched reluctance motors, as a type of high-efficiency speed-regulating motor, have advantages such as simple structure, high reliability, flexible control, and good speed regulation performance. The winding power supply of switched reluctance motors cannot directly use the high-voltage electricity of the power grid as input. It must be rectified into DC power supply and then a power switch is used to realize phase conduction and current amplitude control in order to operate normally. However, the switched reluctance motor itself does not have the ability to run directly on AC three-phase power. Therefore, a corresponding control system is required to cooperate with the power module connected to the winding of the switched reluctance motor in order to realize the starting and speed regulation functions.
[0003] A traditional switched reluctance motor's power module includes a rectifier circuit, a filter circuit, and a drive bridge circuit. The number of drive bridge circuits is the same as the number of phases of the motor's windings. Alternating current passes through the rectifier circuit, filter circuit, and then connects to the drive bridge circuits. The positive and negative output terminals of each drive bridge circuit are connected in series with the corresponding windings in the motor. The drive bridge circuits contain switching transistors (such as IGBTs). The controller controls the switching transistors in the drive bridge circuits to turn them on or off according to a timing sequence, thereby driving the switched reluctance motor.
[0004] However, in existing technologies, the switching transistors in the drive bridge circuit need to withstand high power, while high-voltage power devices are expensive to manufacture, and the voltage withstand rating of semiconductor devices is limited by materials, making it difficult to achieve high voltage withstand ratings such as 6KV or 10KV. Therefore, designing a technical solution that can use low-voltage power switches to achieve drive control of high-voltage switched reluctance motors has become an urgent problem to be solved in this field. Utility Model Content
[0005] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a high-voltage switched reluctance motor cascade control system that connects the drive bridge circuits in multiple power units in series with the windings in the switched reluctance motor, and further realizes the high-voltage output of the switched reluctance motor by controlling the control of each drive bridge circuit and using a switching transistor with a lower withstand voltage rating.
[0006] The technical solution adopted by this utility model to solve its technical problem is as follows: the high-voltage switched reluctance motor cascaded control system includes a power unit, which includes a rectifier circuit and a drive bridge circuit connected in sequence. AC power is connected to the input terminal of the rectifier circuit, and the output terminal of the rectifier circuit is connected to the input terminal of the drive bridge circuit. The number of drive bridge circuits is the same as the number of windings in the switched reluctance motor and corresponds one-to-one. A main control unit for controlling the on / off state of the drive bridge circuit is also provided. The feature is that: the power unit includes multiple units, and all drive bridge circuits in all power units corresponding to the in-phase windings in the switched reluctance motor are connected in series to form a drive bridge group. The two ends of the drive bridge group are connected to the corresponding windings in the switched reluctance motor.
[0007] Preferably, an isolation transformer is provided, with AC power connected to the primary side of the isolation transformer, and multiple secondary sides of the isolation transformer respectively connected to the input terminal of the rectifier circuit in each power unit.
[0008] Preferably, a startup circuit is provided at the output terminal of the rectifier circuit. The startup circuit includes a resistor and a switch connected in parallel. The output terminal of the rectifier circuit is connected to the drive bridge circuit through the startup circuit.
[0009] Preferably, a filter circuit is also provided between the start-up circuit and the drive bridge circuit.
[0010] Preferably, the drive bridge circuit adopts an H-bridge drive circuit composed of a switching transistor and a diode.
[0011] Preferably, in the drive bridge group formed by connecting drive bridge circuits in series, the positive output of the first H-bridge circuit is connected to one end of the corresponding winding, the negative output of the first H-bridge circuit is connected to the positive output of the next stage H-bridge circuit, and the negative output of the last H-bridge circuit is connected to the other end of the corresponding winding.
[0012] Preferably, a high-voltage disconnect switch is also provided between the AC power supply and the primary side of the isolation transformer.
[0013] Compared with the prior art, the beneficial effects of this utility model are:
[0014] In this application, the drive bridge circuits in multiple power units are connected in series and then connected to the windings in the switched reluctance motor. By controlling the control of each drive bridge circuit, high voltage output to the switched reluctance motor is further achieved by using a switching transistor with a lower withstand voltage rating. Attached Figure Description
[0015] Figure 1 This is a block diagram illustrating the principle of a cascaded control system for a high-voltage switched reluctance motor.
[0016] Figure 2This is a block diagram illustrating the principle of the cascaded power unit structure in a high-voltage switched reluctance motor cascaded control system.
[0017] Figure 3 This is a circuit diagram of the power unit in a cascaded control system for a high-voltage switched reluctance motor. Detailed Implementation
[0018] Figures 1-3 This is the preferred embodiment of the present invention, which is described below in conjunction with the appendix. Figures 1-3 The present invention will be further described below.
[0019] like Figure 1 As shown, a cascaded control system for a high-voltage switched reluctance motor (CRRM) includes a high-voltage disconnect switch, an isolation transformer, and a power drive unit. AC power is connected to the primary side of the isolation transformer via the high-voltage disconnect switch. The secondary side of the isolation transformer is connected to the input terminal of the power drive unit. The power output terminal of the power drive unit is connected to the windings of the switched reluctance motor. A main control unit is also provided, connected to the power drive unit. By controlling the on / off state of the power drive unit, the power output from the isolation transformer is fed into the windings of the switched reluctance motor, driving the switched reluctance motor to operate.
[0020] A current transformer is installed on the connection line between the power drive unit and the switched reluctance motor. The current transformer collects the current on the power drive unit and the switched reluctance motor power supply line, and feeds the collected current value back to the main control unit.
[0021] Combination Figure 2 In this cascaded control system, the power drive unit includes multiple power units: power unit 1, power unit 2, ..., power unit n. Each power unit has the same circuit structure. Taking power unit 1 as an example: the power unit includes a rectifier module, a start-up module, a filter module, and a drive bridge module. The rectifier module, start-up module, filter module, and drive bridge module are connected in sequence.
[0022] The secondary side of the isolation transformer is connected to the AC side of the rectifier module in each power unit. The DC side of the power unit is connected sequentially to the starting module, the filter module, and then to the power input terminal of the drive bridge module. The power output terminal of the drive bridge module is connected to the switched reluctance motor and its windings. Specifically, in this cascaded control system, the drive bridge modules in all power units are connected in series to form multiple drive bridge series groups. In each drive bridge series group, the positive power supply terminal of the drive bridge module at the beginning and the negative power supply terminal of the drive bridge module at the end serve as the positive and negative output terminals of the drive bridge series group, respectively, and are connected to the corresponding windings in the switched reluctance motor.
[0023] Further integration Figure 3 In a switched reluctance motor, there is a A , B , C Taking a three-phase winding as an example for further explanation, in power unit 1, through diodes... D Z 1-1 ~ D Z 1-6 The three-phase bridge full-wave rectifier circuit, as is known in the art, is composed of the aforementioned rectifier module. The U, V, and W phase AC power terminals are connected to the input terminals of the three phases of the three-phase bridge full-wave rectifier circuit. After rectification by the three-phase bridge full-wave rectifier circuit, its positive output terminal is connected to a switch. K One end of 1 and the resistor R 1-1 One end, switch K 1 and resistance R 1-1 The other end is connected to a capacitor C One end of 1; the negative output terminal of the three-phase bridge full-wave rectifier circuit is connected to a capacitor. C The other end of 1. Switches connected in parallel. K 1 and resistance R 1-1 For the aforementioned startup module, the capacitor C 1 refers to the filtering module mentioned above.
[0024] The drive bridge module is an H-bridge circuit known in the art, composed of diodes and switching transistors. The number of H-bridge drive circuits in each bridge drive module is the same as the number of windings in the switched reluctance motor. Specifically, taking power unit 1 as an example: [The text abruptly ends here, likely due to an incomplete sentence or missing information.] T 1-1 collector and diode D 1-1 The cathode is switched K 1 and resistance R 1. Connect the positive output terminal of the rectifier circuit and the switching transistor. T 1-1 emitter connection diode D 1-2 cathode, diode D 1-1 anode connection switch tube T 1-2 collector, diode D 1-2 anode and switching transistor T 1-2 The emitter is connected to the negative output terminal of the rectifier circuit. Self-switching transistor. T 1-1 emitter and diode D 1-2 Terminals are led out between the cathodes. A+, as power unit 1 A Phase winding output positive terminal, self-switching transistor T 1-2 emitter and diode D 1-1 Terminals are led out between the cathodes to serve as power unit 1. A The phase winding outputs the negative terminal.
[0025] Switching transistor T 1-3 collector and diode D 1-3 The cathode is switched K 1 and resistance R 1. Connect the positive output terminal of the rectifier circuit and the switching transistor. T 1-3 emitter connection diode D 1-4 cathode, diode D 1-3 anode connection switch tube T 1-3 collector, diode D 1-4 anode and switching transistor T 1-4 The emitter is connected to the negative output terminal of the rectifier circuit. Self-switching transistor. T 1-3 emitter and diode D 1-4 Terminals are led out between the cathodes. B +, as power unit 1 B Phase winding output positive terminal, self-switching transistor T 1-4 emitter and diode D 1-3 Terminals are led out between the cathodes to serve as power unit 1. B The phase winding outputs the negative terminal.
[0026] Switching transistor T 1-5 collector and diode D 1-5 The cathode is switched K 1 and resistance R 1. Connect the positive output terminal of the rectifier circuit and the switching transistor. T 1-5 emitter connection diode D 1-6 cathode, diode D 1-5 anode connection switch tube T 1-5 collector, diodeD 1-6 anode and switching transistor T 1-6 The emitter is connected to the negative output terminal of the rectifier circuit. Self-switching transistor. T 1-5 emitter and diode D 1-6 Terminals are led out between the cathodes. C +, as power unit 1 C Phase winding output positive terminal, self-switching transistor T 1-6 emitter and diode D 1-5 Terminals are led out between the cathodes to serve as power unit 1. C The phase winding outputs the negative terminal.
[0027] The specific circuit structures of power units 2 through N are exactly the same as those of power unit 1, and will not be repeated here. Furthermore, as is generally known in the art, the circuit structure of a single power unit is common knowledge and a conventional method, and the switching transistors can also be implemented using conventional switching devices, such as IG4500. B T, the aforementioned main control unit is connected to the gate of each switching transistor through a conventional drive circuit in order to realize the on / off control of each switching transistor.
[0028] Unlike existing technologies, this cascaded control system connects the H-bridge drive circuits in each power unit in series: the aforementioned terminals... A +At the same time, as part of this cascaded control system, the power drive unit as a whole A The phase winding outputs the positive terminal and is connected to the switched reluctance motor. A One end of the phase winding is connected to the power unit 1. A The negative terminal of the phase winding is connected to the lead-out in power unit 2. A The positive output of the phase winding, ..., is drawn from the power unit N-1. A The negative terminal of the phase winding is connected to the lead-out point in power unit N. A The positive output of the phase winding is drawn from the power unit N. A Phase winding output negative terminal A -), as part of this cascaded control system, the power drive unit as a whole A The phase winding outputs the negative terminal and is connected to the switched reluctance motor. A The other end of the phase winding is connected.
[0029] Power units 1 through N correspond to switched reluctance motors B phase and CThe phase windings use the same circuit structure: terminals B +As a whole power drive unit B The phase winding outputs the positive terminal and is connected to the switched reluctance motor. B One end of the phase winding is connected to the power unit 1. B The negative terminal of the phase winding is connected to the lead-out in power unit 2. B The positive output of the phase winding, ..., is drawn from the power unit N-1. B The negative terminal of the phase winding is connected to the lead-out point in power unit N. B The positive output of the phase winding is drawn from the power unit N. B Phase winding output negative terminal B -), as part of this cascaded control system, the power drive unit as a whole B The phase winding outputs the negative terminal and is connected to the switched reluctance motor. B The other end of the phase winding is connected.
[0030] terminal C +As a whole power drive unit C The phase winding outputs the positive terminal and is connected to the switched reluctance motor. C One end of the phase winding is connected to the power unit 1. C The negative terminal of the phase winding is connected to the lead-out in power unit 2. C The positive output of the phase winding, ..., is drawn from the power unit N-1. C The negative terminal of the phase winding is connected to the lead-out point in power unit N. C The positive output of the phase winding is drawn from the power unit N. C Phase winding output negative terminal C -), as part of this cascaded control system, the power drive unit as a whole C The phase winding outputs the negative terminal and is connected to the switched reluctance motor. C The other end of the phase winding is connected.
[0031] The specific working process and working principle are as follows:
[0032] The main control unit can control the operation of any one or more power units in the power drive unit to control the output voltage to the switched reluctance motor windings. Specifically, the power unit corresponding to... A The H-bridge circuit with phase windings is explained as follows: When the main control unit controls the two switching transistors (switching transistors) in the H-bridge circuit... T 1-1 and switching transistors T 1-2When both the positive and negative output transistors of the H-bridge circuit are conducting, the output voltage between the positive and negative outputs is the output voltage of the rectifier circuit. When the main control unit controls one of the two switching transistors in the H-bridge circuit to be conducting and the other to be off, the positive and negative outputs of the H-bridge circuit can be considered as short-circuited.
[0033] Because all power units correspond to A The H-bridge circuits of the phase windings are connected in series, so when all power units correspond to A When both switching transistors in the H-bridge circuit of the phase winding are in the ON state, the load on the switched reluctance motor is... A The voltage of the phase winding is the sum of the output voltages of all rectifier circuits in all power units; when the voltage of the phase winding corresponds to the voltage of the phase winding in all power units, the voltage of the phase winding is the sum of the output voltages of all rectifier circuits in all power units. A When both switching transistors in the H-bridge circuit of the phase winding are in a state where one is on and the other is off, the load on the switched reluctance motor is... A The voltage of the phase winding is zero.
[0034] Therefore, by controlling the conduction state of the two switching transistors in each H-bridge circuit of each power unit, the output voltage of the power unit is controlled, thereby further achieving high voltage output of the switched reluctance motor by using switching transistors with lower withstand voltage ratings.
[0035] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this utility model without departing from its technical solution shall still fall within the protection scope of this utility model.
Claims
1. A cascaded control system for a high-voltage switched reluctance motor, comprising a power unit, wherein the power unit includes a rectifier circuit and a drive bridge circuit connected in sequence, AC power is connected to the input terminal of the rectifier circuit, the output terminal of the rectifier circuit is connected to the input terminal of the drive bridge circuit, the number of drive bridge circuits is the same as and corresponds one-to-one with the number of windings in the switched reluctance motor, and a main control unit for controlling the on / off state of the drive bridge circuit is also provided, characterized in that: The power unit includes multiple units. All drive bridge circuits corresponding to the in-phase windings in the switched reluctance motor are connected in series to form a drive bridge group. The two ends of the drive bridge group are connected to the corresponding windings in the switched reluctance motor.
2. The high-voltage switched reluctance motor cascade control system according to claim 1, characterized in that: An isolation transformer is provided, with AC power connected to the primary side of the isolation transformer, and multiple secondary sides of the isolation transformer connected to the input terminals of the rectifier circuits in each power unit.
3. The high-voltage switched reluctance motor cascade control system according to claim 1, characterized in that: A startup circuit is provided at the output of the rectifier circuit. The startup circuit includes a resistor and a switch connected in parallel. The output of the rectifier circuit is connected to the drive bridge circuit through the startup circuit.
4. The high-voltage switched reluctance motor cascade control system according to claim 3, characterized in that: A filter circuit is also provided between the startup circuit and the drive bridge circuit.
5. The high-voltage switched reluctance motor cascade control system according to claim 1, characterized in that: The drive bridge circuit adopts an H-bridge drive circuit composed of switching transistors and diodes.
6. The high-voltage switched reluctance motor cascade control system according to claim 5, characterized in that: In the drive bridge group formed by connecting drive bridge circuits in series, the positive output of the first H-bridge circuit is connected to one end of the corresponding winding. Starting from the first H-bridge circuit, its negative output is connected to the positive output of the next stage H-bridge circuit, and the negative output of the last H-bridge circuit is connected to the other end of the corresponding winding.
7. The high-voltage switched reluctance motor cascade control system according to claim 2, characterized in that: A high-voltage disconnect switch is also installed between the AC power supply and the primary side of the isolation transformer.