JP6287602B2 - Switched reluctance motor control system - Google Patents

Description

  The present invention relates to a control system for a switched reluctance motor.

  Generally, in a switched reluctance motor, a winding is provided on a salient pole of a stator, and two windings facing each other across a central axis are connected in series to form phases. In such a switched reluctance motor, while one phase is energized, the other phase is not energized. Therefore, a magnetic flux for generating torque is generated by energizing only one phase. Therefore, many windings are required for the winding, and the shape of the motor increases.

  Therefore, the switched reluctance motor of Patent Document 1 has a plurality of windings between salient poles wound around a yoke portion, and forms two winding sets in which adjacent salient pole windings are connected in series. Two winding sets generate magnetic flux in the same direction.

Japanese Patent Laid-Open No. 11-113229

  In the switched reluctance motor of Patent Document 1, each winding is connected in series and the same current is applied. Therefore, a leakage magnetic flux that contributes to negative torque is generated, and the torque in the saturation region of the magnetic flux may be reduced. .

  Moreover, in the switched reluctance motor of Patent Document 1, since all phases are energized simultaneously in all driving regions, there is no phase where the current becomes zero. For this reason, when switching the excitation in the high-speed drive region, a current response delay occurs in the winding in which the current is reversed, and there is a concern that the torque may be reduced.

  In view of the above circumstances, it is a primary object of the present invention to provide a switched reluctance motor control system capable of realizing both downsizing and high controllability.

  In order to solve the above-described problems, the present invention is a switched reluctance motor control system including a switched reluctance motor and a drive circuit that drives the switched reluctance motor, wherein the motor has an even number of salient poles. A toroidal winding wound in a toroidal manner on a yoke portion connecting between each of the salient poles of the stator, and a rotor having an even number of salient poles that are not in a multiple relationship with the number of salient poles of the stator. An N (phase integer greater than or equal to 2) phase salient pole winding connected in series at positions separated by an electrical angle of 360 degrees, and the drive circuit is connected in parallel to a power source, An energization path capable of energizing current between both the positive direction and the negative direction is provided for each phase in the inter-pole winding, and current can be energized from the energization path to the salient pole winding independently for each phase.

  In the switched reluctance motor of the present invention, a magnetic flux is generated by energizing an N-phase salient pole winding in which the toroidal winding of the yoke portion is connected in series at positions separated by an electrical angle of 360 degrees. In addition, the drive circuit has a current-carrying path that allows current to flow from both the positive direction and the negative direction to the inter-saliency windings for each phase, and independently supplies current from the current-carrying path to the salient-pole windings for each phase. Can be energized.

  Therefore, if the direction of the current flowing through the salient pole winding is appropriately set and N phases are energized simultaneously, a magnetic flux in the same direction can be generated for each of the N toroidal winding sets. Therefore, the number of turns of the individual toroidal windings can be reduced to 1 / N when the magnetic flux is generated by energizing only one phase. Thereby, the amount of windings can be reduced and the motor can be miniaturized. Further, since the polarity and magnitude of the current flowing through the inter-salient winding can be changed for each phase, the controllability of the motor can be improved. Therefore, both miniaturization and high controllability can be realized.

The figure which shows the structure of the control system of SR motor. The figure which shows the structure of the drive circuit of U phase. The figure which shows the drive area | region of control mode AC. The figure which shows the current waveform of each phase in the control mode A. The figure which shows the aspect which a rotor rotates. The figure which shows the current waveform of each phase in the control mode B. The figure which shows the current waveform of each phase in the control mode B. The figure which shows the current waveform of each phase in the control mode C. The figure which shows the current waveform of each phase in the control mode C. The figure which shows a flux linkage distribution. The figure which shows the average torque with respect to an electric current execution value. The figure which shows the torque with respect to an electrical angle. The figure which shows the structure of SR motor which concerns on other embodiment.

  Hereinafter, an embodiment embodying a control system for a switched reluctance motor (hereinafter referred to as an SR motor) will be described with reference to the drawings. As shown in FIG. 1, the SR motor control system according to the present embodiment includes an SR motor 10 and a drive circuit 30 that drives the SR motor 10.

  The SR motor 10 according to this embodiment includes a stator 11 having six salient poles 11a to 11f, a rotor 12 having four salient poles 12a to 12d, and three-phase salient pole windings 21 to 23. Is provided. The U-phase salient-pole winding 21 is a series connection of toroidal windings 21a and 21b at positions separated by an electrical angle of 360 degrees. Similarly, the interphase salient-pole winding 22 of the V phase is a series connection of toroidal windings 22a and 22b at positions separated by an electrical angle of 360 degrees. Further, the interphase salient pole winding 23 of the W phase is formed by connecting toroidal windings 23a and 23b at positions separated by an electrical angle of 360 degrees in series. The toroidal windings 21a to 23a and 21b to 23b are windings wound in a toroidal shape on a yoke portion 11g that connects between the salient poles 11a to 11f of the stator 11. Toroidal windings adjacent in the circumferential direction of the stator 11 are wound around the yoke portion 11g in different directions.

  The drive circuit 30 includes an energization path connected in parallel to the battery 37 (power supply) for each phase, converts the DC power output from the battery 37 into three phases, and supplies the three-phase power to the SR motor 10. The U-phase energization path includes switching elements 31a to 31d and can energize current between the salient pole winding 21 from both the positive direction and the negative direction. The V-phase energization path includes switching elements 32a to 32d, and can supply current to both the salient pole windings 22 from both the positive and negative directions. The W-phase energization path includes switching elements 33a to 33d, and is capable of energizing current from the salient pole winding 23 from both the positive direction and the negative direction. The drive circuit 30 can energize current from the energization path to the inter-saliency winding by setting the magnitude of the current and energization direction for each phase independently, that is, for each phase.

  In the present embodiment, IGBTs (Insulated Gate Bipolar Transistors) are used as the switching elements 31a to d, 32a to d, and 33a to d. The switching elements 31a to d, 32a to d, and 33a to d may be MOSFETs, bipolar transistors, or the like. Diodes 41a-d, 42a-d, 43a-d are connected in antiparallel to the switching elements 31a-d, 32a-d, 33a-d, respectively.

  Since the energization paths of the respective phases have the same configuration, only the U-phase energization paths will be described below with reference to FIG. 2, and descriptions of the V-phase and W-phase energization paths will be omitted. The U-phase energization path is a full bridge circuit including a series body in which two switching elements 31a and 31b are connected in series and a series body in which two switching elements 31c and 31d are connected in series. It is. The emitter terminal of the switching element 31a and the collector terminal of the switching element 31b are connected at a connection point T1. The emitter terminal of the switching element 31c and the collector terminal of the switching element 31d are connected at a connection point T2. Then, both ends of the salient pole winding 21 are connected to connection points T1 and T2, which are the midpoints of the series body.

  The collector terminal of the switching element 31 a and the cathode of the diode 41 a are connected to the first end of the smoothing capacitor 35 and the positive terminal of the battery 37. The emitter terminal of the switching element 31 b and the anode of the diode 41 b are connected to the second end of the smoothing capacitor 35 and the negative terminal of the battery 37. The collector terminal of the switching element 31 c and the cathode of the diode 41 c are connected to the first end of the smoothing capacitor 36 and the positive terminal of the battery 37. The emitter terminal of the switching element 31 d and the anode of the diode 41 d are connected to the second end of the smoothing capacitor 36 and the negative terminal of the battery 37.

  Each of the switching elements 31a to 31d is operated by an operation signal transmitted from a controller (not shown). Here, the direction from the connection point T1 to T2 is the positive direction, and the direction from the connection point T2 to T1 is the negative direction. When the switching elements 31a and 31d are turned on and the switching elements 31b and 31c are turned off, a closed circuit including the battery 37, the switching element 31a, the salient-pole winding 21, and the switching element 31d is formed. As a result, a positive current flows through the inter-saliency winding 21. When the switching elements 31a and 31d are turned off and the switching elements 31b and 31c are turned on, a closed circuit including the battery 37, the switching element 31c, the salient pole winding 21 and the switching element 31b is formed. As a result, a negative current flows through the inter-salient winding 21.

  Next, the control mode of the SR motor 10 will be described with reference to FIG. In this embodiment, there are three control modes A, B, and C. The control mode A is a mode in which the SR motor 10 is driven in a region of a rotational speed that is smaller than a predetermined torque and less than or equal to a predetermined rotational speed, that is, a low torque low speed region. The control mode B is a mode in which the SR motor 10 is driven in a region where the torque is equal to or higher than the predetermined torque and the rotational speed is equal to or lower than the predetermined rotational speed, that is, a high torque low speed region. In the control mode B, the SR motor 10 is driven in the magnetic saturation region in order to obtain a high torque. The control mode C is a mode in which the SR motor 10 is driven in a region where the torque is smaller than the predetermined torque and the rotational speed is higher than the predetermined rotational speed, that is, the low torque high speed region. Hereinafter, embodiments in which the SR motor 10 is driven in each control mode will be described.

Example 1
A first embodiment in which the SR motor 10 is driven in the control mode A will be described with reference to FIGS. 4 and 5. In the control mode A, the SR motor 10 is driven in a region where no magnetic saturation occurs. As shown in FIG. 4, in the control mode A, the waveform of the current to be passed through the inter-saliency windings 21 to 23 of each phase is energized in the positive direction in the half cycle Th of one electrical angle cycle, and the remaining half It is a rectangular wave current waveform which becomes negative direction energization with period Th. By operating the switching elements included in the current paths of the respective phases by the controller, the currents having the above waveforms are passed through the windings 21 to 23. If the values of the currents flowing through the salient pole windings 21 to 23 of each phase are U, V, and W, the amplitudes | U |, | V |, | W | of the rectangular current waveform are equal to each other. In the control mode A, a current in the same direction is supplied to two phases of the three-phase salient pole windings, and a current in a direction different from that of the other two phases is supplied to the remaining one phase. A magnetic flux is generated around a phase in which a current in a direction different from that of the other two phases is applied.

  (A) When U, V> 0 and W <0, as indicated by the arrows in FIG. 5, the magnetic flux emitted from the toroidal winding 22b is generated in the same direction in the toroidal winding 23a. It is sucked toward the toroidal winding 23a. Similarly, the magnetic flux emitted from the toroidal winding 23a is sucked toward the toroidal winding 21b because the same direction of magnetic flux is generated in the toroidal winding 21b. Therefore, a magnetic flux in the direction from the toroidal windings 22b to 21b is generated along the yoke portion 11g with the winding set of toroidal windings 22b, 23a, and 21b centering on the W-phase toroidal winding 23a. Similarly, the winding set of toroidal windings 21a, 23b, and 22a generates a magnetic flux in the direction from the toroidal winding 21a to 22a around the W-phase toroidal winding 23b along the yoke portion 11g.

  And the magnetic flux of both directions opposes in the salient pole 11b. Since the magnetic flux tends to flow along a path with a small magnetic resistance, the magnetic fluxes in both directions are merged at the salient pole 11b and flow as salient pole 11b → saliency pole 12b → saliency pole 12d → saliency pole 11e. Thereby, the salient poles 12b and 12d of the rotor 12 are attracted to the salient poles 11b and 11e of the stator 11, respectively, and torque in the R direction (counterclockwise direction) is generated in the rotor 12.

  The magnetic flux generated by the winding is determined by the product of the number of windings and the current. Therefore, if the total number of turns of the three toroidal windings is the same as the number of turns of the winding wound around one salient pole, the case where magnetic flux is generated by three toroidal windings and one The same magnetic flux is generated when the magnetic flux is generated by the winding wound around the pole. Therefore, assuming that the number of turns of each toroidal winding is the same, when generating magnetic flux with three toroidal windings, each toroidal winding is compared with the case of generating magnetic flux with a winding wound around one salient pole. The number of turns can be reduced to one third.

  (B) When the excitation is switched to U> 0, V, W <0, a magnetic flux in the direction from the toroidal winding 23a to 22a is generated by the winding set of the toroidal windings 23a, 21b, 22a. Further, a magnetic flux in the direction from the toroidal winding 22b to 23b is generated by the winding set of the toroidal windings 22b, 21a, and 23b. The magnetic fluxes in both directions are merged at the salient pole 11c and flow in the order of the salient pole 11c → the salient pole 12c → the salient pole 12a → the salient pole 11f. As a result, the salient poles 12a and 12c of the rotor 12 are attracted to the salient poles 11f and 11c of the stator, respectively.

  (C) When the excitation is switched to U, W> 0 and V <0, a magnetic flux in the direction from the toroidal winding 21b to 22b is generated by the winding set of the toroidal windings 21b, 22a, and 23b. In addition, a magnetic flux in the direction from the toroidal winding 23a to 21a is generated by the winding set of the toroidal windings 23a, 22b, and 21a. The magnetic fluxes in both directions are merged at the salient pole 11d and flow as salient pole 11d → saliency pole 12d → saliency pole 12b → saliency pole 11a. As a result, the salient poles 12b and 12d of the rotor 12 are attracted to the salient poles 11a and 11d of the stator, respectively.

  (D) When the excitation is switched to U, V <0, W> 0, a magnetic flux in the direction from the toroidal winding 22a to 21a is generated by the winding set of the toroidal windings 22a, 23b, 21a. Further, a magnetic flux in the direction from the toroidal winding 21b to 22b is generated by the winding set of the toroidal windings 21b, 23a, and 22b. The magnetic fluxes in both directions are merged at the salient pole 11e and flow in the order of the salient pole 11e → the salient pole 12a → the salient pole 12c → the salient pole 11b. As a result, the salient poles 12a and 12c of the rotor 12 are attracted to the salient poles 11e and 11b of the stator, respectively.

  (E) When the excitation is switched to U <0, V, W> 0, a magnetic flux in the direction from the toroidal winding 23b to 22b is generated by the winding set of the toroidal windings 23b, 21a, 22b. Further, a magnetic flux in the direction from the toroidal winding 22a to 23a is generated by the winding set of the toroidal windings 22a, 21b, and 23a. The magnetic fluxes in both directions are merged at the salient pole 11f and flow as follows: salient pole 11f → saliency pole 12b → saliency pole 12d → saliency pole 11c. As a result, the salient poles 12b and 12d of the rotor 12 are attracted to the salient poles 11f and 11c of the stator, respectively.

  (F) When the excitation is switched to U, W <0, V> 0, a magnetic flux in the direction from the toroidal winding 21a to 23a is generated by the winding set of the toroidal windings 21a, 22b, 23a. Further, a magnetic flux in the direction from the toroidal winding 23b to 21b is generated by the winding set of the toroidal windings 23b, 22a, and 21b. The magnetic fluxes in both directions are merged at the salient pole 11a and flow in the order of the salient pole 11a → the salient pole 12c → the salient pole 12a → the salient pole 11d. As a result, the salient poles 12a and 12c of the rotor 12 are attracted to the salient poles 11d and 11a of the stator, respectively. Thereafter, the process returns to (a). When a current is applied in each of the patterns (a) to (f), the rotor 12 rotates by an electrical angle of 360 degrees and a mechanical angle of 180 degrees.

(Example 2)
A second embodiment in which the SR motor 10 is driven in the control mode B will be described with reference to FIG. In the control mode B, the SR motor 10 is driven in the magnetic saturation region in order to obtain a high torque. In the control mode B, the waveform of the current to be passed through the inter-saliency windings of each phase includes the absolute current in the half cycle Th in the positive direction energization and the half cycle Th in the negative direction energization as compared with other periods. There is a period I (predetermined period) in which the values | U |, | V |, and | W | are small. Specifically, in each interphase salient-pole winding, the absolute value of the current in a period in which a current in a direction different from that of the other two-phase inter-salient winding is applied is smaller than the absolute value of the current in the other period. To do. In this embodiment, the current between the salient poles of each phase is applied during a period in which a current is applied in a direction different from that of the other two-phase salient poles, that is, during one third of the half cycle Th. The absolute value of is smaller than other periods. In this embodiment, the absolute value of the current in the period I is smaller than the absolute value of the current in the first embodiment, and the absolute value of the current in the period other than the period I is larger than the absolute value of the current in the first embodiment. Then, the average current effective value of the half cycle Th is made equal to that of the first embodiment.

  In the present embodiment, the direction of the current flowing through the inter-salient windings of each phase is sequentially switched in the same manner as in the first embodiment. Therefore, the direction of the magnetic flux generated sequentially as shown in FIGS. Changes, and the rotor 12 rotates in the R direction.

  In the control mode B, the SR motor 10 is driven in the magnetic saturation region. Therefore, as in the first embodiment, when the absolute values of the currents to be passed through the inter-saliency windings of each phase are made equal, among the winding sets composed of three toroidal windings that generate magnetic flux in the same direction, Leakage magnetic flux is generated from the toroidal winding (see FIG. 10B). This leakage magnetic flux does not contribute to the torque acting on the rotor 12, but contributes to negative torque. That is, the torque acting on the rotor 12 is reduced by the amount of the leakage magnetic flux.

  Therefore, in this embodiment, the absolute value of the current flowing through the central toroidal winding in the winding group consisting of three toroidal windings that generate the magnetic flux in the same direction is the current flowing through the other two toroidal windings. Smaller than the absolute value of. The density of the magnetic flux generated in the inter-salient winding through which a current having a small absolute value flows is smaller than the density of the magnetic flux generated in the inter-salient winding through which a current having a large absolute value flows. Therefore, leakage magnetic flux is suppressed and generation of negative torque is suppressed.

  FIG. 10A shows a simulation result of the magnetic flux distribution when the SR motor 10 is driven with the energization pattern of the second embodiment in the control mode B region. FIG. 10B shows a simulation result of the magnetic flux distribution when the SR motor 10 is driven with the energization pattern of the first embodiment in the control mode B region. 10A and 10B, the arrow indicates the direction of the magnetic flux, and the thicker the arrow, the higher the magnetic flux density. In the region of the control mode B, when the absolute values of the currents of the respective phases are made equal as in the first embodiment, the density of the leakage magnetic flux is higher than in the case where the energization pattern of the second embodiment is energized.

  Further, the simulation results of the average torque with respect to the effective current value when the SR motor 10 is driven with the energization pattern of the second embodiment and the first embodiment are shown by a solid line and a broken line in FIG. 11, respectively. In addition, the simulation results of the torque with respect to the electrical angle when the SR motor 10 is driven with the energization pattern of the second embodiment and the first embodiment in the region of the control mode B are shown by a solid line and a broken line in FIG. As shown in FIG. 11, in the low torque region where the magnetic saturation is not achieved, the difference in average torque between the energization pattern of Example 2 and the energization pattern of Example 1 is small. However, in the magnetic saturation region, the difference between the torque in the energization pattern of Example 2 and the torque in the energization pattern of Example 1 increases as the torque increases. Also, as shown in FIG. 12, the maximum torque value in the energization pattern of the second embodiment is larger than the maximum torque value in the energization pattern of the first embodiment. That is, the generation of negative torque is suppressed in the energization pattern of the second embodiment by the difference between the torque in the energization pattern of the second embodiment and the torque in the energization pattern of the first embodiment.

(Example 3)
A third embodiment in which the SR motor 10 is driven in the control mode B will be described with reference to FIG. In the second embodiment, the absolute value of the current applied to the inter-saliency winding is uniformly reduced in the period I. However, in the third embodiment, after the absolute value of the current is continuously reduced in the period I, Make it bigger. Even in the present embodiment, similarly to the second embodiment, the leakage magnetic flux can be suppressed and the generation of negative torque can be suppressed.

  Various modes in which the absolute value of the current in the period I is made smaller than those in other periods can be considered. For example, in the period I, the absolute value of the current may be decreased stepwise and then increased stepwise. What is necessary is just to select suitably according to the drive state of SR motor 10. FIG.

  Further, according to the driving state of the SR motor 10, at least one of the length of the period I and the absolute value of the current in the period I may be changed. For example, when the driving point determined from the torque and the rotational speed is changed from the driving point having a small torque to the driving point having a large torque in the region of the control mode B, the absolute value of the current in the period I may be further reduced. . Further, when the driving point having a large torque is changed to the driving point having a small torque in the region of the control mode B, the length of the period I may be shortened. That is, the period I may be shorter than the entire period in which current flows in a direction different from the other two-phase salient-pole windings, that is, the period of one third of the half cycle Th. When the torque at the drive point in the region of the control mode B is larger, the absolute value of the current is smaller, and when the period I is shorter as the torque is smaller, the leakage flux can be suppressed according to the drive point.

Example 4
A fourth embodiment in which the SR motor 10 is driven in the control mode C will be described with reference to FIG. In the control mode C, there is always at least one phase in which no current flows in the inter-salient winding. In this embodiment, the phases are set such that the current is not sequentially supplied in the order of the W phase, the U phase, and the V phase for each one-third period of the half cycle Th. In the period in which current is applied in each phase, the current is supplied in the positive direction. That is, in the present embodiment, the current flowing through the inter-saliency windings of each phase is a direct current. Since there is always one phase in which no current flows in the winding between the salient poles, there is no phase in which the current is reversed when switching excitation. Therefore, the response delay of current is suppressed.

  When U, V> 0, and W = 0, no magnetic flux is generated in the toroidal windings 23a and 23b in FIG. 5A. In this case, the magnetic flux emitted from the toroidal winding 22b is sucked toward the toroidal winding 21b. Further, the magnetic flux emitted from the toroidal winding 21a is sucked toward the toroidal winding 22a. That is, in this embodiment, among the winding sets that generate the magnetic flux in the same direction in the first to fourth embodiments, no magnetic flux is generated in the central toroidal winding, and the magnetic flux in the same direction in the two toroidal windings at both ends. Occurs.

  Therefore, when U = 0, V, W> 0, the same magnetic flux as in FIG. 5E is generated, and when U, W> 0, V = 0, the magnetic flux as in FIG. 5C. Occurs. Therefore, when a current is passed through the inter-saliency windings of each phase with the energization pattern of the present embodiment, the rotor 12 rotates by sequentially repeating (a), (e), and (c) of FIG. Further, when the magnetic flux is generated by two toroidal windings as in the present embodiment, the number of turns of each toroidal winding is 2 in comparison with the case where the magnetic flux is generated by a winding wound around one salient pole. It can be reduced to one part.

(Example 5)
The fifth embodiment in which the SR motor 10 is driven in the control mode C will be described with respect to differences from the sixth embodiment with reference to FIG. In the present embodiment, a positive current is applied to the inter-salient windings of each phase for a period of two-thirds of the half cycle Th, and then a current for a period of one-third of the half cycle Th is not supplied. Thereafter, after a negative current is applied for a period of two-thirds of the half cycle Th, a current is not supplied for a period of one-third of the half cycle Th. That is, in the present embodiment, the current flowing through the inter-saliency windings of each phase is alternating current. Further, in two phases in which current flows, currents flow in different directions. In the present embodiment, as in the fourth embodiment, there is always one phase in which no current is passed through the inter-saliency winding. In each interphase salient-pole winding, the direction of the current is switched with a period during which no current is passed. For this reason, since there is no phase in which the current is reversed when switching the excitation, the response delay of the current is suppressed.

  When U> 0, V <0, and W = 0, no magnetic flux is generated in the toroidal windings 23a and 23b in FIG. 5B or 5C. When U = 0, V <0, W> 0, in FIG. 5C or FIG. 5D, no magnetic flux is generated in the toroidal windings 21a and 21b. In the present embodiment, among the winding sets that generate the magnetic flux in the same direction in the first to fourth embodiments, no magnetic flux is generated in the toroidal winding at one end, and the same direction is generated in the other end and the central toroidal winding. Magnetic flux is generated.

  In Example 4, since the magnetic flux is not generated in the central toroidal winding among the winding set including three toroidal windings, the magnetic flux generated in the toroidal winding at one end of the winding set is The force sucked toward the toroidal winding at the other end is weak. Therefore, depending on the position of the rotor 12, the magnetic flux generated in the toroidal winding at one end of the winding set is not sucked toward the toroidal winding at the other end, and the salient poles of the rotor 12. The leakage flux may be generated and negative torque may be generated. In the fifth embodiment, no magnetic flux is generated in the toroidal winding at the one end. Therefore, depending on the position of the rotor 12, the magnetic flux may be applied to the salient pole of the rotor at a position shifted from the salient pole of the stator 11. The torque that does not flow and acts on the rotor 12 may become zero torque. However, in the control mode C, the current flowing in the inter-salient windings of each phase may be either a direct current as in the fourth embodiment or an alternating current as in the fifth embodiment, so that the direct current and the alternating current are switched appropriately. Thus, generation of negative torque and zero torque can be suppressed.

  According to this embodiment described above, the following effects are obtained.

  Since the current between the salient pole windings of a plurality of phases is energized, the number of turns of the individual toroidal windings can be reduced as compared with the case where magnetic flux is generated by energizing only one phase, and the SR motor 10 can be downsized. Moreover, since the polarity and magnitude | size of the electric current which flow into a winding between salient poles can be changed for every phase, the controllability of SR motor 10 can be made high. Therefore, both the miniaturization of SR motor 10 and high controllability can be realized.

  When driving the SR motor in the control modes A and B, the rotor 12 can be stably rotated by making the positive energization period equal to the negative energization period.

  When driving the SR motor in the control mode B, there is a predetermined period in which the absolute value of the current value is smaller than the other periods in the half cycle Th of the waveform of the current flowing through the inter-saliency winding. As a result, the density of the magnetic flux generated in the inter-salient winding through which a current having a small absolute value flows becomes smaller than the density of the magnetic flux generated in the other inter-salient winding. Therefore, the leakage magnetic flux is suppressed, and the generation of negative torque can be suppressed. As a result, when the SR motor 10 is driven in the magnetic saturation region, the torque characteristics can be improved.

  -The higher the torque of the SR motor 10 is, the higher the density of the magnetic flux generated in the inter-saliency winding becomes, and the more easily the leakage magnetic flux is generated. Therefore, according to the driving state of the SR motor 10, by changing at least one of the length of the period in which the absolute value of the current is reduced and the current value, the leakage flux is appropriately suppressed and the generation of negative torque is suppressed. it can.

  When driving the SR motor 10 in the control mode C, since there is at least one phase in which no current flows in the inter-saliency winding, there is no phase in which the current is reversed when switching excitation. Therefore, it is possible to drive the SR motor 10 at a high speed while suppressing a delay in response of the current.

  When driving the SR motor 10 in the control mode C, the generation of zero torque and negative torque can be suppressed by switching the current flowing in the winding between the salient poles between direct current and alternating current.

  -Since each salient pole winding is connected to the full bridge circuit, current can be supplied to each salient pole winding from both the positive and negative directions.

  Since the toroidal windings adjacent in the circumferential direction of the stator 11 are wound in different directions, the rotor 12 can be rotated with the same torque characteristics even when the excitation is switched.

(Other embodiments)
As shown in FIG. 13, the stator 11 ′ may be a stator having salient poles on both the inner peripheral side and the outer peripheral side. The SR motor 10 includes a rotor 13 (second rotor) installed on the outer peripheral side of the stator 11 ′ in addition to the rotor 12 installed on the inner peripheral side of the stator 11 ′. It may be. In the SR motor 10, toroidal windings 21a to 23a and 21b to 23b are wound around a yoke portion 11'g that connects between the salient poles of the stator 11 '. Therefore, when the rotor 13 is installed on the outer peripheral side, the magnetic flux generated along the yoke portion 11′g flows not only to the inner rotor 12 but also to the outer rotor 13, and torque acting on the rotor 13 is increased. Occur. Therefore, the magnetic flux generated in the toroidal windings 21a to 23a and 21b to 23b can be effectively used by installing the rotor 13 on the outer peripheral side.

  -The number of salient poles of the stator 11 is not limited to six and may be an even number. Further, the number of salient poles of the rotor 12 is not limited to four, and may be an even number that does not have a multiple relationship with the number of salient poles of the stator 11.

  The SR motor 10 is not limited to a three-phase motor, and may be an N-phase (N is an integer) motor having four or more phases. When not driven in the control mode C, the SR motor 10 may be a two-phase motor.

  DESCRIPTION OF SYMBOLS 10 ... SR motor, 11, 11 '... Stator, 11a-f ... Salient pole, 11g, 11'g ... Yoke part, 12 ... Rotor, 12a-d ... Salient pole, 21-23 ... Winding between salient poles , 21a to 23a, 21b to 23b ... toroidal winding, 30 ... drive circuit.

Claims (7)

A switched reluctance motor (10), and a switched reluctance motor control system comprising a drive circuit (30) for driving the switched reluctance motor,
The motor is
A stator (11) having an even number of salient poles (11a-f);
A rotor (12) having an even number of salient poles (12a-d) not in a multiple relationship with the number of salient poles of the stator;
Toroidal windings (21a to 23a, 21b to 23b) wound in a toroidal shape on yoke portions (11g) connecting between the salient poles of the stator were connected in series at positions separated by an electrical angle of 360 degrees. N (integer greater than or equal to 2) phase salient pole windings (21 to 23),
The drive circuit is connected in parallel to a power source, and includes an energization path for each phase that allows current to flow from both the positive direction and the negative direction to the inter-saliency winding, and the energization path independently for each phase. Current from the salient pole winding to
Switches according to a driving state determined by the rotational speed of the motor, characterized Rukoto a control unit to switch the phase number of simultaneous energization current to the stator teeth between the winding from the current path to the drive circuit Control system for trilactance motor.   The waveform of the current to be passed through the inter-saliency windings of each phase is a rectangular wave current waveform in which a positive current is supplied in a half cycle of one electrical angle cycle and a negative current is supplied in the remaining half cycle. Item 2. A switched reluctance motor control system according to item 1.   3. The switched reluctance motor control system according to claim 2, wherein there is a predetermined period in which the absolute value of the current is smaller than the other periods in the half cycle in which the energization in the positive direction and the half cycle in which the energization in the negative direction is performed. A switched reluctance motor (10), and a switched reluctance motor control system comprising a drive circuit (30) for driving the switched reluctance motor,
The motor is
A stator (11) having an even number of salient poles (11a-f);
A rotor (12) having an even number of salient poles (12a-d) not in a multiple relationship with the number of salient poles of the stator;
Toroidal windings (21a to 23a and 21b to 23b) wound in a toroidal shape on yoke portions (11g) connecting between the salient poles of the stator were connected in series at positions separated by 360 degrees in electrical angle. N (integer greater than or equal to 2) phase salient pole windings (21 to 23),
The drive circuit is connected in parallel to a power source, and includes an energization path for each phase that allows current to flow from both the positive direction and the negative direction to the inter-saliency winding, and the energization path independently for each phase. Current from the salient pole winding to
The waveform of the current to be passed through the inter-saliency windings of each phase is a rectangular wave current waveform in which positive direction energization is performed in a half cycle of one electrical angle cycle and negative direction energization is performed in the remaining half cycle,
A control system for a switched reluctance motor, wherein there is a predetermined period in which the absolute value of the current is smaller than the other periods in the half cycle that is energized in the positive direction and the half period that is energized in the negative direction. 5. The switched reluctance motor control system according to claim 3, wherein at least one of a length of the predetermined period and an absolute value of the current in the predetermined period is changed according to a driving state of the motor. The energization path of each phase is a bridge circuit including two series bodies in which two switching elements are connected in series,
The switched reluctance motor control system according to any one of claims 1 to 5 , wherein both ends of the salient-pole winding are respectively connected to the midpoints of the two serial bodies. Wherein the toroidal coil adjacent in the circumferential direction of the stator, switched reluctance motor control system according to any one of claims 1 to 6 which is wound in different directions.

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