A wide speed regulation control strategy for switched reluctance motor system

Abstract

This invention discloses a wide-range speed control strategy for switched reluctance motor systems. Addressing the problem of excessively long phase current demagnetization time during high-speed operation of switched reluctance motors, a wide-range speed control strategy is proposed. Based on rotor position, the operating range is determined, and implementation criteria for the wide-range speed control strategy are established. The proposed control strategy requires no additional power supply, does not increase system cost, and simultaneously widens the speed range, increases output power, and improves system control performance and operating efficiency, demonstrating promising engineering application prospects.

Description

Technical Field

[0001] This invention relates to the field of motor control technology. The proposed control strategy can broaden the speed regulation range and is applicable to various types and phase numbers of switched reluctance motor systems. Background Technology

[0002] Switched reluctance motors (SRMs) have no windings or permanent magnets on their rotors, resulting in low rotational inertia and excellent high-speed performance, making them suitable for applications in aerospace, electric vehicles, and intelligent manufacturing. However, at high speeds, SRMs exhibit a large back electromotive force, leading to a smaller rate of change in current and a significantly prolonged demagnetization time. This makes them prone to entering the negative torque generation region, thereby reducing system efficiency and shortening the speed range. To broaden the speed range, scholars both domestically and internationally have undertaken extensive work in recent years, primarily in the following three aspects: (1) designing novel motor topologies, but the long prototype research and manufacturing cycle increases the difficulty of implementing this strategy; (2) designing novel power converters with front-end boost devices, but this strategy often leads to increased system costs; (3) researching novel control strategies such as model prediction and feedforward compensation, but these strategies rely heavily on accurate model information, making implementation difficult. In conclusion, further research is warranted on broadening the speed range of switched reluctance motors. Summary of the Invention

[0003] The present invention aims to at least partially solve one of the technical problems in the related art.

[0004] Therefore, one object of the present invention is to propose a wide speed control strategy for a switched reluctance motor system, characterized in that:

[0005] The switched reluctance motor system is driven by a low-cost self-boosting power converter and consists of three parts: a power supply unit, a common bridge arm unit, and a phase bridge arm unit. The power supply unit consists of a DC power supply Us connected in series with a capacitor C, with the positive terminal of the power supply connected to the negative terminal of the capacitor. The common bridge arm unit consists of two switching transistors V... 低 V 高 and a diode D 公共 Composition, V 低 The collector is connected to the positive terminal of the power supply, V 高 The collector of the capacitor is connected to the positive terminal of the capacitor, V 低 emitter, V 高 emitter and D 公共 The cathodes are connected to form winding node 1; the phase bridge arm unit consists of N phase bridge arms, where N is an integer greater than or equal to 2, and each phase bridge arm is composed of a switching transistor V. 相 A diode forms D 相 V 相 The emitter of D is connected to the negative terminal of the power supply. 相The cathode is connected to the positive terminal of the capacitor, V 相 The collector of the diode is connected to the anode of the diode to form winding node 2; the phase winding is connected between winding node 1 and winding node 2; the wide speed control strategy includes both capacitor voltage control and current control to shorten the demagnetization time.

[0006] When performing capacitor voltage control, the effects of the six basic single-phase operating modes of the low-cost self-boosting power converter on the capacitor voltage (U) are first analyzed. c The impact of ) ; when operating in high-voltage excitation mode, opening V 高 and V 相 Capacitor discharge, U c Reduce; when operating in low-voltage excitation mode, turn on V 低 and V 相 The current does not pass through the capacitor, U c Unchanged; when the upper transistor has zero voltage freewheeling, V is turned on. 高 , conduct D 相 The current does not pass through the capacitor, U c Unchanged; when the lower transistor has zero voltage freewheeling, V is turned on. 相 , conduct D 公共 The current does not pass through the capacitor, U c Unchanged; when the negative high voltage continues to flow, D is conducting. 公共 and D 相 Capacitor charging, U c When the voltage rises; during negative low-voltage follow current, V is turned on. 低 and D 相 Capacitor charging, U c Increase; define high-voltage excitation mode as mode 1, low-voltage excitation mode as mode 2, upper tube zero-voltage freewheeling mode as mode 3, lower tube zero-voltage freewheeling mode as mode 4, negative high-voltage freewheeling mode as mode 5, and negative low-voltage freewheeling mode as mode 6; then describe the capacitor voltage control strategy for the two-phase common operating range and the single-phase operating range respectively; in the two-phase common operating range, current flows through both the current phase k-th phase winding and the previous phase k-1-th phase winding. This range is divided into three stages: (a) the k-th phase current i k Setup Phase: To quickly establish i k To avoid increasing torque ripple, in i k The establishment phase adopts mode 1, and V is activated. 高 and V 相 The (k-1)th phase current i k-1 The adjustment employs a current hysteresis control method, alternating between mode 1 and mode 3. It is worth noting that during this stage, the capacitor discharges, U... c (b)i k and i k-1 Hysteresis regulation stage: This stage i k The reference current has been reached, when Uc c_ref When -ΔU, to avoid U c Further reduction in the regulation of i k and i k-1 During the process, it is necessary to avoid using mode 1 and instead use one or two of the other basic working modes; if U c >U c_ref +ΔU requires mode 1 to rapidly discharge the capacitor energy until U c equal to U c_ref -ΔU; (c) Demagnetization stage of phase k-1: At this time, phase k-1 operates alternately between mode 5 and mode 6, and phase k operates alternately between mode 2 and mode 3, realizing i k Orderly adjustment; in the single-phase operating range, only the current phase k-th phase winding has current flowing through it, at which time when U c >U c_ref When +ΔU is applied, the k-th phase alternates between mode 1 and mode 4, using mode 1 to quickly discharge capacitor energy and reduce U. c ; when U c c_ref -ΔU, the kth phase alternates between mode 2 and mode 4, U c It remains unchanged.

[0007] When current is input, the capacitor voltage control strategies for the two-phase common operating range and the single-phase operating range are described respectively. In the two-phase common operating range, current flows through both the current phase k-th winding and the previous phase (k-1)-th winding. The amplitude of chopper limit 1 is greater than the amplitude of chopper limit 2. This range is divided into three stages, as shown below: (a) Current i of phase k k Establishment Phase: Phase k quickly establishes current through Mode 1 and enters chopper limit 1; simultaneously, the current i of phase k-1 is adjusted through Modes 1 and 6. k-1 (b)i k and i k-1 Hysteresis regulation stage: Based on the capacitor voltage control strategy, determine whether to select mode 1 or mode 2 when exciting phase k and phase (k-1); when mode 1 is selected, phase k and phase (k-1) alternate between mode 1 and mode 3 to ensure i k Within the chopper limit 1, i k-1 Entering chopper limit 2; when mode 2 is selected, the k-th phase and the (k-1)-th phase alternate between mode 2 and mode 6 to ensure i k Within the chopper limit 1, i k-1 Entering chopper limit 2; (c) Demagnetization stage of phase k-1. At this time, drive V 低 This causes the (k-1)th phase to alternate between mode 5 and mode 6; when V 低 ​​When activated, phase k operates in mode 2, and i is increased. k ; while in V 低 When shut down, phase k operates in mode 3, and i is reduced. k To ensure rapid demagnetization of phase k-1 while maintaining i k Within chopper limit 1; to shorten the demagnetization time, the amplitude of chopper limit 1 is higher than that of chopper limit 2; in the single-phase operating range, only the current phase k-th phase winding has current flowing through it. Based on the capacitor voltage control strategy, it is determined whether to select mode 1 or mode 2 when exciting the k-th and (k-1)-th phases. When mode 1 is selected, the k-th phase alternates between mode 1 and mode 3 to ensure i k Within chopper limit 1; when mode 2 is selected, the k-th phase alternates between mode 2 and mode 6 to ensure i k Within the chopper limit 1.

[0008] The following section uses a four-phase switched reluctance motor as an example to further elaborate on the wide-range speed control strategy proposed in this invention.

[0009] The switched reluctance motor is driven by a low-cost self-boosting power converter, which consists of three parts: a power supply unit, a common bridge arm unit, and a phase bridge arm unit. The power supply unit consists of a DC power supply Us connected in series with a capacitor C, the positive terminal of the power supply connected to the negative terminal of the capacitor. The common bridge arm unit consists of two switching transistors V5 and V6 and a diode D5. The collector of V5 is connected to the positive terminal of the power supply, the collector of V6 is connected to the positive terminal of the capacitor, and the emitters of V5 and V6 are connected to the cathode of the diode, forming winding node 1. The phase bridge arm unit consists of N phase bridge arms, where N is an integer greater than or equal to 2. Each phase bridge arm consists of a switching transistor and a diode. The emitter of the switching transistor is connected to the negative terminal of the power supply, the cathode of the diode is connected to the positive terminal of the capacitor, and the collector of the switching transistor is connected to the anode of the diode, forming winding node 2. Phase windings are connected between winding node 1 and winding node 2.

[0010] The wide-range speed control strategy includes capacitor voltage control and current control. Specifically, when performing capacitor voltage control, the impact of the six basic operating modes of the low-cost self-boosting power converter on the capacitor voltage (U) is first analyzed. c The influence of ) ; When operating in high-voltage excitation mode, the capacitor discharges, U c In the three operating modes—low voltage excitation, upper MOSFET zero-voltage freewheeling, and lower MOSFET zero-voltage freewheeling—current does not pass through the capacitor, so the capacitor neither discharges nor charges. U c Unchanged; in both negative high-voltage freewheeling and negative low-voltage freewheeling modes, the capacitor charges, U c Increase, negative high voltage follow current U cSince the rate of increase is greater than that of negative voltage, we define the high-voltage excitation mode as Mode 1, the low-voltage excitation mode as Mode 2, the upper tube zero-voltage freewheeling mode as Mode 3, the lower tube zero-voltage freewheeling mode as Mode 4, the negative high-voltage freewheeling mode as Mode 5, and the negative low-voltage freewheeling mode as Mode 6. Then, we analyze the capacitor voltage control strategies for the two-phase common operating range and the single-phase operating range respectively.

[0011] When analyzing the two-phase co-operating range, we take phase D and phase A as an example. This range operates in three stages: (a)i a Setup Phase: To quickly establish i a To avoid increasing torque ripple, in i a The setup phase adopts Mode 1, enabling V6 and V1. And i d The regulation employs a current hysteresis control method, alternating between high-voltage excitation mode and upper-tube zero-voltage freewheeling mode. It is worth noting that during this stage, the capacitor discharges, U... c (b)i a and i d Hysteresis regulation phase: when U c c_ref When -ΔU, to ensure U c Amplitude, reduce switching frequency, in adjustment i a and i d During the process, mode 1 should be avoided, and one or two of the other basic operating modes should be used instead. This is because the capacitor current may be greater than 0 in the aforementioned modes, therefore U c It has increased to some extent; if U c >U c_ref +ΔU requires mode 1 to rapidly discharge the capacitor energy until U c equal to U c_ref -ΔU;(c) D-phase demagnetization stage: At this time, the D-phase operates alternately between mode 5 and mode 6 to ensure rapid demagnetization of the D-phase under negative pressure. The A-phase operates in mode 2 and mode 3 to achieve i a The orderly regulation.

[0012] In the single-phase operating range, taking phase A working alone as an example, when U c >U c_ref When +ΔU is applied, phase A operates in modes 1 and 4. Mode 1 is used to quickly discharge capacitor energy and reduce U. c ; when U c c_ref -ΔU, Phase A operates in Mode 2 and Mode 4, U c It remains unchanged.

[0013] When using current-driven control, the capacitor voltage control strategies for the two-phase common operating region and the single-phase operating region are analyzed separately:​​

[0014] When analyzing the two-phase co-operating interval, we take phase D and phase A as examples. This interval operates in three stages, as shown below: (a)i a Establishment phase: Phase A quickly establishes current through mode 1 and enters chopper limit 1; simultaneously, through adjustment of mode 1 and mode 6, phase D enters chopper limit 2; (b)i a and i d Hysteresis Regulation Stage: Based on the capacitor voltage control strategy, determine whether to select mode 1 or mode 2 when exciting phases A and D; when mode 1 is selected, phases A and D alternate between mode 1 and mode 3 to ensure i a Within the chopper limit 1, i d Within chopper limit 2; when mode 2 is selected, phases A and D alternate between mode 2 and mode 6 to ensure i a Within the chopper limit 1, i d Within chopper limit 2; (c) D-phase demagnetization stage. At this time, drive V5 to make D-phase operate alternately between mode 5 and mode 6; when V5 is turned on, A-phase operates in mode 2, increasing i a When V5 is turned off, phase A operates in mode 3, reducing i. a Thus, while rapidly demagnetizing the D phase, i is guaranteed. a Within chopper limit 1; in order to shorten the demagnetization time, the amplitude of chopper limit 1 is higher than the amplitude of chopper limit 2.

[0015] In the single-phase operating range, taking phase A operating alone as an example, the current control strategy is explained. Based on the capacitor voltage control strategy, it is determined whether to select mode 1 or mode 2 when phases A and D are excitationd. When mode 1 is selected, phase A alternates between mode 1 and mode 3 to ensure i a Within the chopper limit 1; when mode 2 is selected, phase A alternates between mode 2 and mode 6 to ensure i a Within the chopper limit 1.

[0016] The beneficial effects of this invention are as follows: The wide speed control strategy of the switched reluctance motor system of this invention can simultaneously adjust the demagnetization region from two aspects: DC bus voltage boost and demagnetization time adjustment, thereby widening the speed range, improving the high-speed operation performance and efficiency of the switched reluctance motor, and laying the foundation for the further promotion of the application of switched reluctance motors. Attached Figure Description

[0017] Figure 1 This is the implementation process of the wide speed control strategy described in this invention.

[0018] Figure 2 It is a low-cost self-boosting power converter for four-phase switched reluctance motors.

[0019] Figure 3 This is the basic operating mode for a low-cost self-boosting power converter.

[0020] Figure 4 The graph shows the capacitor voltage regulation results during steady-state operation.

[0021] Figure 5 This is a current control process.

[0022] Figure 6 The diagram shows the current control results during steady-state operation. Detailed Implementation

[0023] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0024] The following describes a wide-range speed control strategy for a switched reluctance motor system according to an embodiment of the present invention, with reference to the accompanying drawings.

[0025] The wide speed control strategy for switched reluctance motor systems proposed in this invention is as follows: Figure 1 As shown. The switched reluctance motor is driven by a low-cost self-boosting power converter, such as... Figure 2 The system consists of three parts: a power supply unit, a common bridge arm unit, and a phase bridge arm unit. The power supply unit comprises a DC power supply Us connected in series with a capacitor C, the positive terminal of the power supply connected to the negative terminal of the capacitor. The common bridge arm unit comprises two switching transistors V5 and V6 and a diode D5. The collector of V5 is connected to the positive terminal of the power supply, the collector of V6 is connected to the positive terminal of the capacitor, and the emitters of V5 and V6 are connected to the cathode of the diode, forming winding node 1. The phase bridge arm unit comprises N phase bridge arms, where N is an integer greater than or equal to 2. Each phase bridge arm consists of a switching transistor and a diode. The emitter of the switching transistor is connected to the negative terminal of the power supply, the cathode of the diode is connected to the positive terminal of the capacitor, and the collector of the switching transistor is connected to the anode of the diode, forming winding node 2. Phase windings are connected between winding node 1 and winding node 2.

[0026] The wide-range speed control strategy includes capacitor voltage control and current control. Specifically, when performing capacitor voltage control, the impact of the six basic operating modes of the low-cost self-boosting power converter on the capacitor voltage (U) is first analyzed. c The influence of ) ; When operating in high-voltage excitation mode, the capacitor discharges, U c In the three operating modes—low voltage excitation, upper MOSFET zero-voltage freewheeling, and lower MOSFET zero-voltage freewheeling—current does not pass through the capacitor, so the capacitor neither discharges nor charges. U cUnchanged; in both negative high-voltage freewheeling and negative low-voltage freewheeling modes, the capacitor charges, U c Increase, negative high voltage follow current U c The rate of increase is greater than that of the negative voltage. We define the high-voltage excitation mode as Mode 1, the low-voltage excitation mode as Mode 2, the upper tube zero-voltage freewheeling mode as Mode 3, the lower tube zero-voltage freewheeling mode as Mode 4, the negative high-voltage freewheeling mode as Mode 5, and the negative low-voltage freewheeling mode as Mode 6. Figure 3 As shown. Then, the capacitor voltage control strategies for the two-phase common operating range and the single-phase operating range are analyzed respectively.

[0027] When analyzing the two-phase co-operating range, we take phase D and phase A as an example. This range operates in three stages: (a)i a Setup Phase: To quickly establish i a To avoid increasing torque ripple, in i a The setup phase adopts Mode 1, enabling V6 and V1. And i d The regulation employs a current hysteresis control method, alternating between high-voltage excitation mode and zero-voltage freewheeling mode on the upper tube. It is worth noting that during this stage, the capacitor discharges, U... c (b)i a and i d Hysteresis regulation phase: when U c c_ref When -ΔU, to ensure U c Amplitude, reduce switching frequency, in adjustment i a and i d During the process, mode 1 should be avoided, and one or two of the other basic operating modes should be used instead. This is because the capacitor current may be greater than 0 in the aforementioned modes, therefore U c It has increased to some extent; if U c >U c_ref +ΔU requires mode 1 to rapidly discharge the capacitor energy until U c equal to U c_ref -ΔU;(c) D-phase demagnetization stage: At this time, the D-phase operates alternately between mode 5 and mode 6 to ensure rapid demagnetization of the D-phase under negative pressure. The A-phase operates in mode 2 and mode 3 to achieve i a The orderly regulation.

[0028] In the single-phase operating range, taking phase A working alone as an example, when U c >U c_ref When +ΔU is applied, phase A operates in modes 1 and 4. Mode 1 is used to quickly discharge capacitor energy and reduce U. c ; when U c c_ref ​​-ΔU, Phase A operates in Mode 2 and Mode 4, U c It remains unchanged.

[0029] The control results of the proposed wide-range speed control strategy for the switched reluctance motor system on the capacitor voltage are as follows: Figure 4 As shown.

[0030] The proposed wide-range speed control strategy for switched reluctance motor systems implements a current control process to shorten demagnetization time, as follows: Figure 5 As shown. When using current control to shorten the demagnetization time, the capacitor voltage control strategies for the two-phase common operating range and the single-phase operating range are analyzed separately:

[0031] When analyzing the two-phase co-operating interval, we take phase D and phase A as examples. This interval operates in three stages, as shown below: (a)i a Establishment phase: Phase A quickly establishes current through mode 1 and enters chopper limit 1; simultaneously, through adjustment of mode 1 and mode 6, phase D enters chopper limit 2; (b)i a and i d Hysteresis Regulation Stage: Based on the capacitor voltage control strategy, determine whether to select mode 1 or mode 2 when exciting phases A and D; when mode 1 is selected, phases A and D alternate between mode 1 and mode 3 to ensure i a Within the chopper limit 1, i d Within chopper limit 2; when mode 2 is selected, phases A and D alternate between mode 2 and mode 6 to ensure i a Within the chopper limit 1, i d Within chopper limit 2; (c) D-phase demagnetization stage. At this time, drive V5 to make D-phase operate alternately between mode 5 and mode 6; when V5 is turned on, A-phase operates in mode 2, increasing i a When V5 is turned off, phase A operates in mode 3, reducing i. a Thus, while rapidly demagnetizing the D phase, i is guaranteed. a Within chopper limit 1; in order to shorten the demagnetization time, the amplitude of chopper limit 1 is higher than the amplitude of chopper limit 2.

[0032] In the single-phase operating range, taking phase A operating alone as an example, the current control strategy is explained. Based on the capacitor voltage control strategy, it is determined whether to select mode 1 or mode 2 when phases A and D are excitationd. When mode 1 is selected, phase A alternates between mode 1 and mode 3 to ensure i a Within the chopper limit 1; when mode 2 is selected, phase A alternates between mode 2 and mode 6 to ensure i a Within the chopper limit 1.

[0033] The proposed wide-range speed control strategy for switched reluctance motor systems demonstrates the following results in shortening demagnetization time and controlling current: Figure 6As shown.

[0034] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A speed control strategy for a switched reluctance motor system, characterized in that: The switched reluctance motor system is driven by a self-boosting power converter, and consists of three parts: a power supply unit, a common bridge arm unit, and a phase bridge arm unit. The power supply unit comprises a DC power supply Us and a capacitor C connected in series, with the positive terminal of the power supply and the negative terminal of the capacitor connected together. The common bridge arm unit consists of two switching transistors V 低 V 高 and a diode D 公共 Composition, V 低 The collector is connected to the positive terminal of the power supply, V 高 The collector of the capacitor is connected to the positive terminal of the capacitor, V 低 emitter, V 高 emitter and D 公共 The cathodes are connected to form winding node 1; the phase bridge arm unit consists of N phase bridge arms, where N is an integer greater than or equal to 2, and each phase bridge arm consists of a switching transistor V phase and a diode D. 相 V 相 The emitter of D is connected to the negative terminal of the power supply. 相 The cathode is connected to the positive terminal of the capacitor, V 相 The collector of the diode is connected to the anode of the diode to form winding node 2; the winding node 1 and winding node 2 are connected to the phase winding; the wide speed regulation control strategy first determines whether the operating range is a two-phase common working range or a single-phase working range according to the rotor position, and then executes capacitor voltage control and current control to shorten the demagnetization time accordingly. When operating in high-voltage excitation mode, V is turned on. 高 and V 相 Capacitor discharge, capacitor voltage U c Reduce; when operating in low-voltage excitation mode, turn on V 低 and V 相 The current does not pass through the capacitor, U c Unchanged; when the upper transistor has zero voltage freewheeling, V is turned on. 高 , conduct D 相 The current does not pass through the capacitor, U c Unchanged; when the lower transistor has zero voltage freewheeling, V is turned on. 相 , conduct D 公共 The current does not pass through the capacitor, U c Unchanged; when the negative high voltage continues to flow, D is conducting. 公共 and D 相 Capacitor charging, U c When the voltage rises; during negative low-voltage follow current, V is turned on. 低 and D 相 Capacitor charging, U c Increase; define high voltage excitation mode as mode 1, low voltage excitation mode as mode 2, upper tube zero voltage freewheeling mode as mode 3, lower tube zero voltage freewheeling mode as mode 4, negative high voltage freewheeling mode as mode 5, and negative low voltage freewheeling mode as mode 6. When current control is performed, in the two-phase common operating range, current flows through both the current phase k-th phase winding and the previous phase (k-1)-th phase winding. The amplitude of chopper limit 1 is greater than the amplitude of chopper limit 2. This range is divided into three stages, as shown below: (a) Current i in phase k k Establishment Phase: Phase k quickly establishes current through Mode 1 and enters chopper limit 1; simultaneously, the current i of phase k-1 is adjusted through Modes 1 and 6. k-1 (b)i k and i k-1 Hysteresis regulation stage: Based on the capacitor voltage control strategy, determine whether to select mode 1 or mode 2 when exciting phase k and phase (k-1); when mode 1 is selected, phase k and phase (k-1) alternate between mode 1 and mode 3 to ensure i k Within the chopper limit 1, i k-1 Entering chopper limit 2; when mode 2 is selected, the k-th phase and the (k-1)-th phase alternate between mode 2 and mode 6 to ensure i k Within the chopper limit 1, i k-1 (c) Entering the chopper limit 2; (k-1) Demagnetization stage of phase k: At this time, drive V 低 This causes the (k-1)th phase to alternate between mode 5 and mode 6; when V 低 When activated, phase k operates in mode 2, and i is increased. k ; while in V 低 When shut down, phase k operates in mode 3, and i is reduced. k To ensure rapid demagnetization of phase k-1 while maintaining i k Within chopper limit 1; in order to shorten the demagnetization time, the amplitude of chopper limit 1 is higher than the amplitude of chopper limit 2.

2. According to the speed control strategy of the switched reluctance motor system as described in claim 1, when performing capacitor voltage control, the effects of the six single-phase basic operating modes of the self-boosting power converter on the capacitor voltage U are first analyzed. c The impact; then the capacitor voltage control strategies for the two-phase common operating range and the single-phase operating range are described respectively; in the two-phase common operating range, current flows through both the current phase k-th phase winding and the previous phase (k-1)-th phase winding. This range is divided into three stages: (a) the current i of phase k k Setup Phase: To quickly establish i k To avoid increasing torque ripple, in i k The establishment phase adopts mode 1, and V is activated. 高 and V 相 The (k-1)th phase current i k-1 The adjustment employs a current hysteresis control method, alternating between mode 1 and mode 3. It is worth noting that during this stage, the capacitor discharges, U... c (b)i k and i k-1 Hysteresis regulation stage: This stage i k The reference current has been reached, when U c c_ref When -ΔU, to avoid U c Further reduction in the regulation of i k and i k-1 During the process, it is necessary to avoid using mode 1 and instead use one or two of the other basic working modes; if U c >U c_ref +ΔU requires mode 1 to rapidly discharge the capacitor energy until U c equal to U c_ref -ΔU; (c) Demagnetization stage of phase k-1: At this time, phase k-1 operates alternately between mode 5 and mode 6, and phase k operates alternately between mode 2 and mode 3, realizing orderly adjustment of ik; In the single-phase operating range, only the current phase k-phase winding has current flowing through it, at this time when U c >U c_ref When +ΔU is applied, the k-th phase alternates between mode 1 and mode 4, using mode 1 to quickly discharge capacitor energy and reduce U. c ; when U c c_ref -ΔU, the kth phase alternates between mode 2 and mode 4, U c It remains unchanged.​​ 3. According to the speed control strategy of the switched reluctance motor system as described in claim 1, when performing current control, in the single-phase operating range, only the current phase k-th phase winding has current flowing through it. Based on the capacitor voltage control strategy, it is determined whether to select mode 1 or mode 2 when exciting the k-th and (k-1)-th phases. When mode 1 is selected, the k-th phase alternates between mode 1 and mode 3 to ensure i k Within chopper limit 1; when mode 2 is selected, the k-th phase alternates between mode 2 and mode 6 to ensure i k Within the chopper limit 1.

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