JP2021016262A - Control method for three-phase reluctance motor and control device for three-phase reluctance motor - Google Patents

Abstract

To provide a control method for a three-phase reluctance motor and a control device for a three-phase reluctance motor that can obtain high efficiency regardless of whichever rotational torque is small or large.SOLUTION: A device comprises a first operation mode in which stator teeth 12 (A1) and 12 (A2), 12 (B1) and 12 (B2), 12 (C1) and 12 (C2) are magnetized into opposite polarities with respect to each other by passing predetermined drive currents ia1 to ic2 through coils 14 (A1) to 14 (C2) to operate a three-phase reluctance motor 10 as a switched reluctance motor. The device comprises a second operation mode in which the stator teeth 12 (A1) and 12 (A2), 12 (B1) and 12 (B2), 12 (C1) ) and 12 (C2) are magnetized into a same polarity with respect to each other by passing the predetermined drive currents ia1 to ic2 through the coils 14 (A1) to 14 (C2) to operate the three-phase reluctance motor 10 as a synchronous reluctance motor. When a rotational torque of a rotor 16 is equal to or greater than a reference value Tth, the first mode is selected, and when the rotational torque is less than the reference value Tth, the second mode is selected.SELECTED DRAWING: Figure 3

Description

The present invention relates to a three-phase reluctance motor control method and a three-phase reluctance motor control device that do not use permanent magnets.

Reluctance motors have excellent robustness and have the advantages of being able to be configured without using rare earth magnets, so they are attracting attention in a wide range of fields such as automobile drive motors, industrial fans, pumps, and blowers. Are collecting.

Conventionally, as disclosed in, for example, Patent Document 1, a control device for a switch trilatance motor driven by an exciting current flowing through a three-phase coil, wherein the current flowing in at least one phase of the three-phase coil is used. There was a control device that switched the polarity of the three-phase coil to either the first winding pattern or the second winding pattern by changing the direction. The first winding pattern is a winding pattern in which three-phase coils are wound in the same direction, and the second winding pattern is a winding pattern in which two of the three-phase coils are wound in the same direction and the remaining one. This is a winding pattern in which one is wound in opposite directions and the former two coils and the latter one coil are alternately arranged.

This control device supplies each coil with a current to operate in the first winding pattern at low load (when the switched reluctance motor's rotational torque and rotational speed are in the first region). , Under heavy load (when located in a second region different from the first region), each coil is supplied with a current so as to operate in the second winding pattern. By controlling in this way, the maximum torque can be improved without deteriorating the efficiency of the switched reluctance motor.

JP-A-2018-85904

The efficiency η [%] of the reluctance motor is Tave [Nm] for average torque, Wfe [W] for iron loss, Wcu [W] for copper loss, ω [rad / sec] for rotational angular velocity, and N [rpm] for rotational speed. ], It can be expressed as the following equations (1) and (2).

η = (ω ・ Tave-Wfe) / (ω ・ Tave + Wcu) × 100 (1)
ω = (2π / 60) ・ N (2)
From these equations (1) and (2), it can be seen that in order to increase the efficiency η of the reluctance motor, the iron loss Wfe and the copper loss Wcu should be reduced. However, there are various restrictions when actually designing, and it is not easy to reduce the iron loss Wfe and the copper loss Wcu at the same time.

In general, when a reluctance motor is operated with a relatively large average torque Tave, the main component of the loss is copper loss Wcu (Wcu> Wfe), and when operated with a relatively small average torque Tave, the main component of the loss is. Iron loss Wfe (Wfe> Wcu). When designing a reluctance motor, it is usually important to keep the temperature rise below a certain level while miniaturizing the outer shape, and it is often prioritized to reduce the copper loss Wcu when the average torque Tave is large. Therefore, in order to obtain a high efficiency η when the average torque Tave is small or large, it is an issue to reduce the iron loss Wfe when the average torque Tave is small.

The control device of the switched reluctance motor of Patent Document 1 supplies a current to each coil so as to operate in the first winding pattern under a heavy load (when the average torque Tave is large). This is a normal driving method of a switched reluctance motor, and in the process of rotating the rotor, the magnetic flux passing through the rotor (magnetic material) fluctuates greatly in the positive and negative directions, so that a large iron loss Wfe occurs. However, since the copper loss Wcu is larger under heavy load, even if the iron loss Wfe is slightly large, the efficiency η is not so affected.

On the other hand, when the load is low (when the average torque Tave is small), a current is supplied to each coil so as to operate in the second winding pattern. When driven in this way, the change width of the magnetic flux passing through the rotor becomes slightly smaller and the iron loss Wfe becomes smaller, so that the efficiency η becomes higher accordingly.

As described above, when the control method of the control device of Patent Document 1 is used, the iron loss Wfe when the average torque Tave is small becomes a little small, and the efficiency η when the average torque Tave is small can be increased accordingly. .. However, since the decrease in iron loss Wfe is small, the efficiency η cannot be significantly improved.

The present invention has been made in view of the above background technology, and provides a control method for a three-phase reluctance motor and a three-phase reluctance motor control device that can obtain high efficiency when the rotational torque is small or large. The purpose.

In the present invention, a plurality of stator teeth are projected on the inner peripheral surface of a cylinder, and a stator in which a coil is wound around each stator is arranged coaxially inside the stator. It is a control method of a three-phase reluctance motor provided with a rotor having a plurality of rotor teeth protruding from the outer peripheral surface.
The plurality of coils are divided into k sets (k is a natural number) of A1 coils and A2 coils, k sets (k is a natural number) of B1 coils and B2 coils, and k sets (k is a natural number) of C1 coils and C2 coils. Then, the k sets are arranged at equal intervals in the order of A1, B2, C1, A2, B1, and C2 in the circumferential direction of each of the coils.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized in opposite polarities at the same timing, and the drive currents are supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized in opposite polarities at the same timing, and the C1 and C2 coils are wound around the C1 and C2 coils. A first operation mode in which the three-phase reluctance motor is operated as a switch reluctance motor by supplying a driving current so that the stator teeth are magnetized in opposite polarities at the same timing.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized to the same polarity at the same timing, and the drive current is supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized at the same timing and with the same polarity, and the C1 and C2 coils are wound around the C1 and C2 coils. A second operation mode for operating the three-phase reluctance motor as a synchronous reluctance motor is set by supplying a drive current so that the stator teeth are magnetized at the same timing and with the same polarity. ,
When the rotational torque of the rotor is equal to or higher than the reference value, the three-phase reluctance motor is operated in the first mode, and when it is less than the reference value, the three-phase reluctance motor is operated in the second mode. This is a control method for a three-phase reluctance motor.

Further, in the present invention, a plurality of stator tooth portions are projected on the inner peripheral surface of the cylinder, and a stator in which a coil is wound around each stator tooth portion is arranged coaxially inside the stator. A three-phase reluctance motor control device that controls the operation of a three-phase reluctance motor including a rotor having a plurality of rotor teeth projecting on the outer peripheral surface.
The plurality of coils are divided into k sets (k is a natural number) of A1 coils and A2 coils, k sets (k is a natural number) of B1 coils and B2 coils, and k sets (k is a natural number) of C1 coils and C2 coils. Then, the k sets are arranged at equal intervals in the order of A1, B2, C1, A2, B1, and C2 in the circumferential direction of each of the coils.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized in opposite polarities at the same timing, and the drive currents are supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized in opposite polarities at the same timing, and the C1 and C2 coils are wound around the C1 and C2 coils. A first operation mode in which the three-phase reluctance motor is operated as a switch reluctance motor by supplying a driving current so that the stator teeth are magnetized in opposite polarities at the same timing.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized to the same polarity at the same timing, and the drive current is supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized at the same timing and with the same polarity, and the C1 and C2 coils are wound around the C1 and C2 coils. A second operation mode for operating the three-phase reluctance motor as a synchronous reluctance motor is set by supplying a drive current so that the stator teeth are magnetized at the same timing and with the same polarity. ,
When the rotational torque of the rotor is equal to or higher than the reference value, the three-phase reluctance motor is operated in the first mode, and when it is less than the reference value, the three-phase reluctance motor is operated in the second mode. It is a three-phase reluctance motor control device.

In particular, the A1 coil, the A2 coil, the B1 coil, the B2 coil, the C1 coil, and the six full-bridge PWM inverters that individually drive the C2 coil are provided, and the first and second operation modes are provided. It is preferable that the switching is performed by changing the switching sequence of each of the full bridge type PWM inverters.

Alternatively, it has first to sixth arms composed of a series circuit of two switching elements, and the A1 coil and the A2 are located between the midpoint of the first arm and the midpoint of the second arm. A series circuit of the coil is connected, and a series circuit of the B1 coil and the B2 coil is connected between the midpoint of the third arm and the midpoint of the fourth arm, and the series circuit of the B1 coil and the B2 coil is connected to the fifth arm. A series circuit of the C1 coil and the C2 coil is connected between the middle point and the middle point of the sixth arm, and the connection point of the A1 and A2 coils, the connection point of the B1 and B2 coils, and the C1 The PWM inverter for driving each coil is provided in a state where the connection points of the C2 coil and the connection point of the C2 coil are connected to each other, and the switching of the first and second operation modes is changed by changing the switching sequence of the PWM inverter. It is preferable to make the configuration performed by the above.

The three-phase reluctance motor control method and the three-phase reluctance motor control device of the present invention switch the operation mode according to the magnitude of the rotation torque of the rotor, and switch the three-phase reluctance motor when the rotation torque is large. (First operation mode), and when the rotational torque is small, it is operated as a synchronous reluctance motor (second operation mode). By performing this unique control, iron loss when the rotational torque is small is significantly reduced, and high efficiency can be obtained when the rotational torque is large or small.

In addition, the switched reluctance motor tends to have problems of noise and vibration when the rotational torque is small. However, in the present invention, when the rotational torque is small, the three-phase reluctance motor is operated as a synchronous reluctance motor, so that noise and vibration are generated. Vibration problems are less likely to occur.

It is a figure which shows the structure of the three-phase reluctance motor which is controlled. It is a circuit diagram which shows one Embodiment of the three-phase reluctance motor control apparatus of this invention. It is a figure (a) which showed two operation modes set in the control device of this embodiment, and a graph (b) which shows the setting method of the reference value of the rotational torque at the time of switching operation modes. It is a graph which shows the example of the waveform of the drive current supplied to each coil by the control device of this embodiment (the first operation mode). It is a timing chart which shows the switching sequence of the drive circuit which the control device of this embodiment has (the first operation mode). It is a figure (a)-(c) which shows the flow of the magnetic flux at the timing T11-T13 shown in FIG. 4 in order. It is a figure (a)-(c) which shows the flow of the magnetic flux at the timing T14-T16 shown in FIG. 4 in order. It is a graph which shows the example of the waveform of the drive current supplied to each coil by the control device of this embodiment (second operation mode). It is a timing chart which shows the switching sequence of the drive circuit which the control device of this embodiment has (the second operation mode). 8 (a) to (c) show the flow of magnetic flux at timings T21 to T23 shown in FIG. 8 in order. 8 (a) to (c) show the flow of magnetic flux at timings T24 to T26 shown in FIG. 8 in order. It is a circuit diagram which shows the modification of the three-phase reluctance motor control device. It is a graph (a), (b), (c) which shows the example of the waveform of the drive current supplied to each coil by the three-phase reluctance motor control device of FIG. 12 (the first operation mode). It is a graph (a), (b), (c) which shows the example of the waveform of the drive current supplied to each coil by the three-phase reluctance motor control device of FIG. 12 (second operation mode). It is a graph (a), (b), (c) which shows the waveform of the drive current of each coil used in the simulation of the 1st operation mode in Example 1. FIG. It is a graph (a), (b), (c) which shows the waveform of the drive current of each coil used in the simulation of the 2nd operation mode in Example 1. FIG. It is a figure which shows the simulation result in Example 1, and is the graph (a) which shows the characteristic of iron loss, the graph (b) which shows the characteristic of copper loss, and the graph (c) which shows the characteristic of efficiency. It is a graph (a), (b), (c) which shows the change example of the waveform of the drive current of each coil used in the simulation of the 2nd operation mode in Example 1. FIG.

Hereinafter, an embodiment of the three-phase reluctance motor control device of the present invention will be described with reference to FIGS. 1 to 11. In addition, one embodiment of the control method of the three-phase reluctance motor of this invention is carried out by this three-phase reluctance motor control device.

First, an example of the basic structure of the controlled three-phase reactance motor will be briefly described. The three-phase reluctance motor 10 shown in FIG. 1 includes a cylindrical stator 12 and a rotor 16 coaxially arranged inside the stator 12.

On the inner peripheral surface of the stator 12, six stator teeth 12 (A1), 12 (B2), 12 (C1), 12 (A2), 12 (B1), 12 ( C2) are projected in order, and the driving coils 14 (A1), 14 (B2), 14 (C1), 14 (A2), 14 (B1), and 14 (C2) are provided in each stator tooth. It is being wound. The dots in the vicinity of the coils 14 (A1) to 14 (C2) in FIG. 1 indicate the winding direction.

Further, four rotor teeth 16 (R1) to 16 (R4) are sequentially provided on the outer peripheral surface of the rotor 16 at equal intervals in the clockwise direction.

The inductance La of the coils 12 (A1) and 12 (A2) becomes maximum when any of the rotor teeth 16 (R1) to 16 (R4) approaches and faces each other, and decreases when they are separated. The same applies to the inductance Lb of the coils 12 (B1) and 12 (B2) and the inductance Lc of the coils 12 (C1) and 12 (C2). That is, each inductance increases and decreases periodically as the rotor 14 rotates.

In the graph of FIG. 4, the change in inductance La to Lc when the horizontal axis is the rotation angle θ (see FIG. 1) is shown by a thin broken line. As shown in the upper graph, the inductance La becomes maximum when θ = 0,90,180,270 deg and minimizes when θ = 45,135,225,315 deg. As shown in the middle graph, the inductance Lb changes with a phase delay of 30 deg with respect to the inductance La. Further, as shown in the lower graph, the inductance Lc changes with a phase delay of 60 deg with respect to the inductance La.

Next, the three-phase reluctance motor control device 18 of this embodiment will be described. As shown in FIG. 2, the three-phase reluctance motor control device 18 has six drive circuits 20 (A1), 20 (A2), 20 (B1), 20 (B2), 20 (C1), and 20 (C2). I have. The drive circuit 20 (A1) is a circuit that supplies a predetermined drive current ia1 to the coil 14 (A1), and has a so-called full-bridge type PWM inverter configuration. The first arm is a series circuit of the switching elements SW1 (A1) and SW2 (A1), the switching element SW1 (A1) is arranged on the high side side, and the dot of the coil 14 (A1) is attached to the midpoint. One end is connected. The second arm is a series circuit of the switching element SW3 (A1) and the switching element SW4 (A1), the switching element SW3 (A1) is arranged on the high side side, and the coil 14 (A1) and others are located at the midpoint. The ends are connected.

The drive circuit 20 (A2) is a circuit that supplies a predetermined drive current ia2 to the coil 14 (A2), and has the same full-bridge type PWM inverter configuration as the drive circuit 20 (A1). The first arm is a series circuit of the switching element SW1 (A2) and the switching element SW2 (A2), the switching element SW1 (A2) is arranged on the high side side, and the dot of the coil 14 (A2) is placed at the midpoint. One end marked with is connected. The second arm is a series circuit of the switching element SW3 (A2) and the switching element SW4 (A2), the switching element SW3 (A2) is arranged on the high side side, and the coil 14 (A2) is located at the midpoint. The ends are connected.

The drive circuits 20 (B1) and 20 (B2) are circuits that supply predetermined drive currents ib1 and ib2 to the coils 14 (B1) and 14 (B2), and are the same as the drive circuits 20 (A1) and 20 (A2). It has the configuration of a full bridge type PWM inverter. Further, the drive circuits 20 (C1) and 20 (C2) are circuits that supply predetermined drive currents ic1 and ic2 to the coils 14 (C1) and 14 (C2), and are drive circuits 20 (A1) and 20 (A2). It has the same configuration as the full bridge type PWM inverter. The switching operations of the six drive circuits 20 (A1) to 20 (C2) are collectively controlled by a switching control unit (not shown).

The dots in the vicinity of the coils 14 (A1) to 14 (C2) in FIG. 2 indicate the winding direction of the coils and correspond to the dots in FIG. Further, the arrows attached in the vicinity of the coils 14 (A1) to 14 (C2) define the positive direction of the drive currents ia1 to ic2. Hereinafter, regarding the direction in which the drive currents ia1 to ic2 flow, the direction of the arrow (the direction of flowing into one end with a dot) is referred to as a positive direction, and the direction opposite to the arrow is referred to as a negative direction.

Two operation modes are set in advance in the three-phase reluctance motor control device 18. In the first operation mode, the switching control unit controls the switching operation of the six drive circuits 20 (A1) to 20 (C2) to operate the three-phase reluctance motor 10 as a switched reluctance motor [SRM]. is there. In the second operation mode, the switching control unit controls the switching operation of the six drive circuits 20 (A1) to 20 (C2) to operate the three-phase reluctance motor 10 as a synchronous reluctance motor [SynRM]. The mode.

Details will be described later in the operation description, but in the first operation mode, the stator teeth 12 (A1), 12 in which each coil is wound around the coils 14 (A1) and 14 (A2). The drive currents ia1 and ia2 are supplied so that (A2) magnetize each other with opposite polarities (N pole and S pole). Further, with respect to the coils 14 (B1) and 14 (B2), the stator teeth 12 (B1) and 12 (B2) around which the coils are wound are magnetized to opposite polarities (N pole and S pole). The drive currents ib1 and ib2 are supplied so as to do so. Further, with respect to the coils 14 (C1) and 14 (C2), the stator teeth 12 (C1) and 12 (C2) around which the coils are wound are magnetized to opposite polarities (N pole and S pole). The drive currents ic1 and ic2 are supplied so as to do so. As a result, the three-phase reluctance motor 10 is operated as a switched reluctance motor.

Further, in the second operation mode, the stator teeth 12 (A1) and 12 (A2) around which the coils are wound are magnetized with the same polarity with respect to the coils 14 (A1) and 14 (A2). The drive currents ia1 and ia2 are supplied so as to do so. Further, with respect to the coils 14 (B1) and 14 (B2), the drive currents ib1 and so that the stator teeth 12 (B1) and 12 (B2) around which the coils are wound are magnetized with the same polarity. Supply ib2. Further, with respect to the coils 14 (C1) and 14 (C2), the drive current ic1, so that the stator teeth 12 (C1) and 12 (C2) around which the coils are wound are magnetized with the same polarity. Supply ic2. As a result, the three-phase reluctance motor 10 is operated as a synchronous reluctance motor.

The switching control unit determines which operation mode is selected. As shown in FIG. 3A, the switching control unit selects the first operation mode when the rotational torque is equal to or greater than the reference value Tth, and selects the second operation mode when the rotational torque is less than the reference value Tth.

FIG. 3B shows the efficiency characteristics when the three-phase reluctance motor 10 is always operated as a switched reactance motor [SRM] and the efficiency characteristics when the three-phase reluctance motor 10 is always operated as a synchronous reluctance motor [SynRM]. Shown. As can be seen by comparing the two efficiency characteristics, the value of the rotational torque that maximizes the efficiency η is lower in the latter. This is because the iron loss Wfe becomes smaller and the copper loss Wcu becomes larger when operating as a synchronous reluctance motor [SynRM].

When determining the reference value Tth, it is preferable to actually measure the efficiency characteristics shown in FIG. 3B in advance and set the point Tx at which the magnitude relationship between the two efficiency characteristics is reversed as the reference value Tth. When selecting the operation mode, the switchon control unit may select the operation mode based on the detection result of the rotation torque (or the characteristic value corresponding to the rotation torque) during the actual operation, or the control command value of the rotation torque may be selected. It may be selected based on.

Next, the operation of the three-phase reluctance motor control device 18 and the three-phase reluctance motor 10 will be described. When the switching control unit selects the first operation mode, the drive circuit 20 (A1) supplies the drive current ia1 shown in the upper graph of FIG. 4 toward the coil 14 (A1). That is, while the inductance La of the coil 14 (A1) is increasing, a drive current ia1 (for example, a trapezoidal drive current) is passed in the negative direction, and a large rotation occurs in the rotor teeth 16 (R1) to 16 (R4). Apply torque. As shown in FIG. 5, the current in the negative direction is obtained by fixing the switching elements SW1 (A1) and SW4 (A1) to off and turning the switching elements SW2 (A1) and SW3 (A1) on and off in the same phase. generate.

The drive circuit 20 (A2) supplies the drive current ia2 shown in the upper graph of FIG. 4 toward the coil 14 (A2). That is, while the inductance La of the coil 14 (A2) is increasing, the drive current ia2 (for example, trapezoidal current) is passed in the positive direction, and a large rotational torque is applied to the rotor teeth 16 (R1) to 16 (R4). To act. As shown in FIG. 5, this positive current is obtained by fixing the switching elements SW2 (A2) and SW3 (A2) to off and turning the switching elements SW1 (A2) and SW4 (A2) on and off in the same phase. generate.

The drive circuit 20 (B1) supplies the drive current ib1 shown in the middle graph of FIG. 4 toward the coil 14 (B1). That is, while the inductance Lb of the coil 14 (B1) is increasing, the drive current ib1 (for example, trapezoidal current) is passed in the negative direction, and a large rotational torque is applied to the rotor teeth 16 (R1) to 16 (R4). To act. The waveform of the drive current ib1 is similar to the waveform of the drive current ia1, and can be generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A1) of FIG.

The drive circuit 20 (B2) supplies the drive current ib2 shown in the middle graph of FIG. 4 toward the coil 14 (B2). That is, while the inductance Lb of the coil 14 (B2) is increasing, the drive current ib2 (for example, trapezoidal current) is passed in the positive direction, and a large rotational torque is applied to the rotor teeth 16 (R1) to 16 (R4). To act. The waveform of the drive current ib2 is similar to the waveform of the drive current ia2, and can be generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A2) of FIG.

The drive circuit 20 (C1) supplies the drive current ic1 shown in the lower graph of FIG. 4 toward the coil 14 (C1). That is, while the inductance Lc of the coil 14 (C1) is increasing, a drive current ic1 (for example, a trapezoidal current) is passed in the negative direction, and a large rotational torque is applied to the rotor teeth 16 (R1) to 16 (R4). To act. The waveform of the drive current ic1 is similar to the waveform of the drive circuit ia1, and can be generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A1) of FIG.

The drive circuit 20 (C2) supplies the drive current ic2 shown in the lower graph of FIG. 4 toward the coil 14 (C2). That is, while the inductance Lc of the coil 14 (C2) is increasing, the drive current ib2 (for example, trapezoidal current) is passed in the positive direction, and a large rotational torque is applied to the rotor teeth 16 (R1) to 16 (R4). To act. The waveform of the drive current ic2 is similar to the waveform of the drive current ia2, and can be generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A2) of FIG.

6 (a) to 6 (c) and 7 (a) to 7 (c) show the flow of the magnetic flux φ at the timings T11 to T16 shown in FIG. Timing T11 is when the drive currents ia1 and ia2 are flowing through the coil 14 (A1) and the coil 14 (A2), and the stator teeth 12 (A1) and 12 (A2) are magnetized in opposite polarities ( The magnetic flux φ passes through the rotor 16 (N pole and S pole) in the direction from the rotor tooth portion 16 (R1) to 16 (R3). Timing T12 is when the drive currents ib1 and ib2 are flowing through the coil 14 (B1) and the coil 14 (B2), and the stator teeth 12 (B1) and 12 (B2) are magnetized in opposite polarities ( The magnetic flux φ passes through the rotor 16 (N pole and S pole) in the direction from the rotor tooth portion 16 (R2) to 16 (R4). Timing T13 is when the drive currents ic1 and ic2 are flowing through the coil 14 (C1) and the coil 14 (C2), and the stator teeth 12 (C1) and 12 (C2) are magnetized in opposite polarities ( The magnetic flux φ passes through the rotor 16 (N pole and S pole) in the direction from the rotor tooth portion 16 (R3) to 16 (R1).

The timing T14 is when the drive currents ia1 and ia2 are flowing through the coil 14 (A1) and the coil 14 (A2), and the stator teeth 12 (A1) and 12 (A2) are magnetized in opposite polarities ( The magnetic flux φ passes through the rotor 16 (N pole and S pole) in the direction from the rotor tooth portion 16 (R4) to 16 (R2). Timing T15 is when the drive currents ib1 and ib2 are flowing through the coil 14 (B1) and the coil 14 (B2), and the stator teeth 12 (B1) and 12 (B2) are magnetized in opposite polarities ( The magnetic flux φ passes through the rotor 16 (N pole and S pole) in the direction from the rotor tooth portion 16 (R1) to 16 (R3). Timing T16 is when the drive currents ic1 and ic2 are flowing through the coil 14 (C1) and the coil 14 (C2), and the stator teeth 12 (C1) and 12 (C2) are magnetized in opposite polarities ( The magnetic flux φ passes through the rotor 16 (N pole and S pole) in the direction from the rotor tooth portion 16 (R2) to 16 (R4).

As can be seen by comparing FIGS. 6 (a) and 6 (c), the magnetic flux φ passes between the rotor teeth 16 (R1) and 16 (R3) in both the timings T11 and T13. , The directions of the magnetic flux φ are opposite to each other. That is, since the magnetic flux φ swings greatly in the positive and negative directions, a large iron loss Wfe is generated in the rotor 16. Further, as can be seen by comparing FIGS. 6 (b) and 7 (a), the magnetic flux φ passes between the rotor teeth 16 (R2) and 16 (R4) at both the timings T12 and T14. However, the directions of the magnetic flux φ are opposite to each other. That is, since the magnetic flux φ swings greatly in the positive and negative directions, a large iron loss Wfe is generated in the rotor 16.

When the three-phase reluctance motor 10 is operated as a switched reluctance motor [SRM] in this way, a large iron loss Wfe is generated. However, since this first operation mode is selected when the rotational torque is large (when the reference value is Tth or more), as shown in FIG. 3B, even if a certain amount of iron loss Wfe occurs, High efficiency η can be obtained.

When the switching control unit selects the second operation mode, the drive circuit 20 (A1) supplies the drive current ia1 shown in the upper graph of FIG. 8 toward the coil 14 (A1). That is, while the inductance La of the coil 14 (A1) is increasing, the drive current ia1 (for example, trapezoidal drive current) is alternately passed in the negative direction and the positive direction, and the rotor teeth 16 (R1) to 16 ( Apply a large rotational torque to R4). As shown in FIG. 9, the current in the negative direction is obtained by fixing the switching elements SW1 (A1) and SW4 (A1) to off and turning the switching elements SW2 (A1) and SW3 (A1) on and off in the same phase. generate. Further, the current in the positive direction is generated by fixing the switching elements SW2 (A1) and SW3 (A1) to off and turning the switching elements SW1 (A1) and SW4 (A1) on and off in the same phase.

The drive circuit 20 (A2) supplies the drive current ia2 shown in the upper graph of FIG. 8 toward the coil 14 (A2). That is, while the inductance La of the coil 14 (A2) is increasing, the drive current ia2 (for example, trapezoidal current) is alternately passed in the negative direction and the positive direction, and the rotor teeth 16 (R1) to 16 (R4) are alternately applied. ) With a large rotational torque. The waveform of the drive current ia2 is the same as the waveform of the drive current ia1, and is generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A1) of FIG.

The drive circuit 20 (B1) supplies the drive current ib1 shown in the middle graph of FIG. 8 toward the coil 14 (B1). That is, while the inductance Lb of the coil 14 (B1) is increasing, the drive current ib1 (for example, trapezoidal current) is alternately passed in the negative direction and the positive direction, and the rotor teeth 16 (R1) to 16 (R4) are alternately applied. ) With a large rotational torque. The waveform of the drive current ib1 is similar to the waveform of the drive current ia1, and is generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A1) of FIG.

The drive circuit 20 (B2) supplies the drive current ib2 shown in the middle graph of FIG. 8 toward the coil 14 (B2). That is, while the inductance Lb of the coil 14 (B2) is increasing, the drive current ib2 (for example, trapezoidal current) is alternately passed in the negative direction and the positive direction, and the rotor teeth 16 (R1) to 16 (R4) are alternately applied. ) With a large rotational torque. The waveform of the drive current ib2 is the same as the waveform of the drive current ib1, and it is generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A1) of FIG.

The drive circuit 20 (C1) supplies the drive current ic1 shown in the lower graph of FIG. 8 toward the coil 14 (C1). That is, while the inductance Lc of the coil 14 (C1) is increasing, the drive current ic1 (for example, trapezoidal current) is alternately passed in the negative direction and the positive direction, and the rotor teeth 16 (R1) to 16 (R4) are alternately applied. ) With a large rotational torque. The waveform of the drive current ic1 is similar to the waveform of the drive current ia1, and is generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A1) of FIG.

The drive circuit 20 (C2) supplies the drive current ic2 shown in the lower graph of FIG. 8 toward the coil 14 (C2). That is, while the inductance Lc of the coil 14 (C2) is increasing, the drive current ic2 (for example, trapezoidal current) is alternately passed in the negative direction and the positive direction, and the rotor teeth 16 (R1) to 16 (R4) are alternately applied. ) With a large rotational torque. The waveform of the drive current ic2 is the same as the waveform of the drive current ic1, and is generated by turning on and off the four switching elements in the same manner as in the drive circuit 20 (A1) of FIG.

10 (a) to 10 (c) and 11 (a) to 11 (c) show the flow of the magnetic flux φ at the timings T21 to T26 shown in FIG. Timing T21 is when the positive drive currents ia1 and ia2 are flowing through the coil 14 (A1) and the coil 14 (A2), and the stator teeth 12 (A1) and 12 (A2) have the same polarity. It is magnetized (N pole and N pole), and the magnetic flux φ passes through the rotor 16 in the directions from the rotor teeth 16 (R1) 16 (R3) to 16 (R2) and 16 (R4). Timing T22 is when the drive currents ib1 and ib2 in the negative direction are flowing through the coil 14 (B1) and the coil 14 (B2), and the stator teeth 12 (B1) and 12 (B2) have the same polarity. It is magnetized (S pole and S pole), and the magnetic flux φ passes through the rotor 16 in the directions of the rotor teeth 16 (R1), 16 (R3) to 16 (R2), 16 (R4). Timing T23 is when the drive currents ic1 and ic2 in the positive direction are flowing through the coil 14 (C1) and the coil 14 (C2), and the stator teeth 12 (C1) and 12 (C2) have the same polarity. It is magnetized (N pole and N pole), and the magnetic flux φ passes through the rotor 16 in the directions from the rotor teeth 16 (R1), 16 (R3) to 16 (R2), 16 (R4).

Timing T24 is when the drive currents ia1 and ia2 in the negative direction are flowing through the coil 14 (A1) and the coil 14 (A2), and the stator teeth 12 (A1) and 12 (A2) have the same polarity. Magnetized (S pole and S pole), the magnetic flux φ passes through the rotor 16 in the directions from the rotor teeth 16 (R1) 16 (R3) to 16 (R2) and 16 (R4). Timing T25 is when the positive drive currents ib1 and ib2 are flowing through the coil 14 (B1) and the coil 14 (B2), and the stator teeth 12 (B1) and 12 (B2) have the same polarity. It is magnetized (N pole and N pole), and the magnetic flux φ passes through the rotor 16 in the directions from the rotor teeth 16 (R1), 16 (R3) to 16 (R2), 16 (R4). The timing T26 is when the negative drive currents ic1 and ic2 are flowing through the coil 14 (C1) and the coil 14 (C2), and the stator teeth 12 (C1) and 12 (C2) have the same polarity. It is magnetized (S pole and S pole), and the magnetic flux φ passes through the rotor 16 in the directions of the rotor teeth 16 (R1), 16 (R3) to 16 (R2), 16 (R4).

As can be seen from FIGS. 10 and 11, the magnetic flux φ passes through the rotor 16 in the same direction at any timing of T21 to T26. That is, since the magnetic flux φ swings only in one direction, the iron loss Wfe of the rotor 16 becomes significantly smaller.

In this way, when the three-phase reluctance motor 10 is operated as a synchronous reluctance motor [SynRM], the iron loss Wfe can be significantly reduced. Since this second operation mode is selected when the rotational torque is small (when it is less than the reference value Tth), even if a certain amount of copper loss Wcu occurs, high efficiency is achieved as shown in FIG. 3 (b). η is obtained.

As described above, the three-phase reluctance motor control device 18 (and the control method of the three-phase reluctance motor) of this embodiment switches the operation mode according to the magnitude of the rotation torque of the rotor 16, and when the rotation torque is large. Controls the three-phase reluctance motor 10 to operate as a switched reluctance motor (first operation mode) and to operate as a synchronous reluctance motor when the rotational torque is small (second operation mode). By performing this unique control, the iron loss Wfe is significantly reduced when the rotational torque is small, and high efficiency η can be obtained when the rotational torque is large or small.

Further, since the operation mode can be easily switched by changing the switching sequence of the full bridge type PWM inverters 20 (A1) to 20 (C2), the switching of each coil (A1) to 14 (C2) can be easily performed. It is not necessary to provide a relay or a switch for switching the wiring, and the control device can be configured very simply.

Further, the switched reluctance motor tends to have problems of noise and vibration when the rotational torque is small, but the three-phase reluctance motor control device 18 uses the three-phase reluctance motor 10 as a synchronous reluctance motor when the rotational torque is small. Since it is operated, problems of noise and vibration are less likely to occur.

The three-phase reluctance motor control method and the three-phase reluctance motor control device of the present invention are not limited to the above embodiments. In the above embodiment, the waveform of the drive current supplied to each coil is trapezoidal, but the waveform may be other than trapezoidal, for the purpose of reducing copper loss, suppressing noise and vibration, and the like. It can be changed as appropriate. In this regard, if a plurality of full-bridge type PWM inverters are used as in the above-mentioned three-phase reluctance motor control device 18, the waveform of the drive current can be easily and freely adjusted by controlling the on / off duty of the switching element and the like. Can be variable.

The three-phase reluctance motor control device of the present invention may have a configuration like the three-phase reluctance motor control device 22 shown in FIG. The three-phase reluctance motor control device 22 includes a PWM inverter composed of first to sixth arms 24 (1) to 24 (6) including a series circuit of two switching elements.

The first arm 24 (1) has switching elements SW11 and SW12 (SW11 is on the high side), the second arm 24 (2) is switching elements SW21 and SW22 (SW21 is on the high side), and the third arm 24 (SW21 is on the high side). 3) is switching elements SW31 and SW32 (SW31 is on the high side), the fourth arm 24 (4) is switching elements SW41 and SW42 (SW41 is on the high side), and the fifth arm 24 (5) is switching element SW51. And SW52 (SW51 is on the high side), and the sixth arm 24 (6) is composed of switching elements SW61 and SW62 (SW61 is on the high side), respectively.

In the three-phase relaxation motor 10, a series circuit of the coils 14 (A1) and 14 (A2) is connected between the midpoint of the first arm 24 (1) and the midpoint of the second arm 24 (2). , The series circuit of the coils 14 (B1) and 14 (B2) is connected between the midpoint of the third arm 24 (3) and the midpoint of the fourth arm 24 (4), and the fifth arm 24 A series circuit of the coils 14 (C1) and 14 (C2) is connected between the midpoint of (5) and the midpoint of the sixth arm. At this time, each coil is connected in the winding direction represented by dots in FIG. Then, the connection points of the coils 14 (A1) and 14 (A2), the connection points of the coils 14 (B1) and 14 (B2), and the connection points of the coils 14 (C1) and 14 (C2) are connected to each other. A neutral point 26 is provided, and in this state, the six arms 24 (1) to 24 (6) are switched, and each coil is driven. The switching operations of the six arms 24 (1) to 24 (6) are collectively controlled by a switching control unit (not shown).

When the first operation mode for operating the three-phase reluctance motor 10 as a switched reluctance motor [SRM] is selected, the first and second arms 24 (1) and 24 (2) are the switching elements SW12 and SW21. Is fixed to off, and the switching elements SW11 and SW22 are turned on and off in the same phase to supply the drive currents ia1 and ia2 (= −ia1) to the coils 14 (A1) and 14 (A2). The third and fourth arms 24 (3) and 24 (4) fix the switching elements SW32 and SW41 to off, and turn the switching elements SW31 and SW42 on and off in the same phase to drive currents ib1 and ib2 (=). -Ib1) is supplied to the coils 14 (B1) and 14 (B2). The fifth and sixth arms 24 (5) and 24 (6) fix the switching elements SW52 and SW61 to off, and turn the switching elements SW51 and SW62 on and off in the same phase to drive currents ic1 and ic2 (=). -Ic1) is supplied to the coils 14 (C1) and 14 (C2). When operated in this way, the potential at the neutral point 26 is held at 1/2 of the power supply voltage, and no current flows through the line at the neutral point 26.

The waveform of the drive current in the first operation mode can be changed by controlling the on / off duty of each switching element, and the waveform is as shown in FIGS. 13 (a), 13 (b), and 13 (c), for example. can do.

When the second operation mode for operating the three-phase reluctance motor 10 as a synchronous reluctance motor [SynRM] is selected, the first and second arms 24 (1) and 24 (2) are the switching elements SW11 and SW21. Are turned on and off in the same phase as each other, and the switching elements SW12 and SW22 are turned on and off in the same phase as the switching elements SW11 and SW21 by the reverse logic. The third and fourth arms 24 (3) and 24 (4) turn the switching elements SW31 and SW41 on and off in the same phase, and the switching elements SW32 and SW42 are in the same phase as the switching elements SW31 and SW41. Turn it on and off with reverse logic. The fifth and sixth arms 24 (5) and 24 (6) turn the switching elements SW51 and SW61 on and off in the same phase, and the switching elements SW52 and SW62 are in the same phase as the switching elements SW51 and SW61. Turn it on and off with reverse logic.

When operated in this way, a drive current (ia1 + ia2), a drive current (ib1 + ib2), and a drive current (ic1 + ic2) flow in the line of the neutral point 26. At this time, since ia1 = ia2, ib1 = ib2, and ic1 = ic2, each drive current flowing in the line of the neutral point 26 becomes ia1 + ia2 = 2 · ia1, ib1 + ib2 = 2 · ib1, ic1 + ic2 = 2 · ic1. .. Then, the switching of each arm is controlled so that the combined current (2, ia1 + 2, ib1 + 2, ib3) becomes zero. This is the same as the control method of a general three-phase PWM inverter.

The waveform of the drive current in the second operation mode can be changed by controlling the on / off duty of each switching element, for example, the waveforms shown in FIGS. 14A, 14B, and 14C. can do.

The three-phase reluctance motor control device 18 of the above embodiment has six full-bridge type PWM inverters (a total of 12 arms) independent of each other, and is characterized in that the waveform of each drive current can be freely changed. However, the modified example of the three-phase reluctance motor control device 22 is characterized in that the number of arms can be reduced to six to simplify the circuit configuration. In addition, the above-mentioned three-phase reluctance motor 10 is a motor having six stator teeth and four rotor teeth, but the present invention is a three-phase reluctance motor having a larger number of teeth. Can also be applied.

A simulation (two-dimensional finite element method analysis) for confirming the action and effect of the three-phase reluctance motor control device and the control method of the three-phase reluctance motor of the present invention will be described with reference to FIGS. 15 to 18. The three-phase relaxation motor of the analysis model is a motor having 18 stator teeth and 12 rotor teeth, and the 18 coils wound around each stator are A1 coil and A2. Three sets of coils, three sets of B1 and B2 coils, three sets of C1 and C2 coils, and each coil is arranged in the order of A1, B2, C1, A2, B1, C2, A1, ... did. The inductance of each coil is the same.

In the simulation, the characteristics when the three-phase reluctance motor of the analysis model is always operated in the first operation mode and the characteristics when it is always operated in the second operation mode are calculated separately and compared. I made it. The characteristics to be compared are the change in iron loss Wfe, the change in copper loss Wcu, and the change in efficiency η when the average torque Tave is changed.

In the first operation mode, the drive currents ia1 and ia2 as shown in FIG. 15A are supplied to the A1 and A2 coils, respectively, and the drive currents ib1 and ib2 as shown in FIG. 15B are B1 and ib2. It was decided to supply each to the B2 coil and supply the drive currents ic1 and ic2 as shown in FIG. 15C to the C1 and C2 coils, respectively. The waveforms shown in FIGS. 15 (a), 15 (b), and (c) are waveforms when the average torque Tave = 6.5 Nm, and when the average torque Tave is changed, each waveform is made into a substantially similar shape. Changed to be maintained.

In the second operation mode, the drive currents ia1 and ia2 as shown in FIG. 16A are supplied to the A1 and A2 coils, respectively, and the drive currents ib1 and ib2 as shown in FIG. 16B are B1 and ib2. It was decided to supply each to the B2 coil and supply the drive currents ic1 and ic2 as shown in FIG. 16C to the C1 and C2 coils, respectively. The waveforms shown in FIGS. 16A, 16B, and 16C are waveforms when the average torque Tave = 6.5 Nm, and when the average torque Tave is changed, each waveform is made into a substantially similar shape. Changed to be maintained.

The waveforms shown in FIGS. 15 and 16 are waveforms with an emphasis on improving the efficiency η, and in this way, the voltage waveforms (not shown) of each part become square wavy, so that the power supply voltage is maximized. It has the advantage of being able to be used effectively.

The waveforms shown in FIGS. 15 and 16 are different in shape from the waveforms of the drive currents of FIGS. 4 and 8 described above, but when the stator teeth are magnetized. The method of changing the polarity (N pole, S pole) of is the same. Further, for example, comparing the horizontal axes of the drive currents ia1 and ia2, in FIGS. 4 and 8, 90 deg of the rotation angle is one cycle of the electric angle, whereas in FIGS. 15 (a) and 16 (a) In a), the rotation angle of 30 deg is one cycle of the electric angle. This is because the former drives one set of A1 and A2 coils, while the latter drives three sets of A1 and A2 coils. This also applies to the horizontal axes of the drive currents ib1 and ib2 and the drive currents ic1 and ic2. For the same reason, the phase difference between the drive currents ia1 and ia2 and the drive currents ib1 and ib2 and the drive currents ic1 and ic2 is 1/3 of that of the former.

As a result of the simulation, the characteristics shown in FIGS. 17A, 17B, and 17C were obtained. The iron loss Wfe was smaller when always operated in the second operation mode than when always operated in the first operation mode. Further, the copper loss Wcu is smaller when always operated in the first operation mode than when always operated in the second operation mode, and the difference is particularly remarkable in the range of Tave> about 9 Nm. became. The efficiency η is higher when always operated in the second operation mode in the range of Tave <about 9 Nm, and when always operated in the first operation mode in the range of Tave> about 10 Nm. Was higher. The tendency of the characteristic of the efficiency η is almost the same as the characteristic of the efficiency schematically drawn in FIG. 3 (b).

From this simulation result, it can be seen that the reference value Tth of the torque for switching the operation mode should be set to about 10 Nm. That is, in the case of the three-phase reluctance motor of the analysis model, the average torque Tave is obtained by operating the range of Tave ≧ about 10 Nm in the first operation mode and operating the range of Tave <about 10 Nm in the second operation mode. High efficiency η can be obtained both when it is large and when it is small.

In addition, the inventor also performed a simulation when the waveform of the drive current in the second operation mode was made into a sinusoidal waveform shown in FIGS. 18A, 18B, and 18C. This waveform is a waveform that emphasizes suppressing noise and vibration. As a result of the simulation, it was confirmed that the effect intended by the present invention can be obtained.

10 Three-phase reluctance motor 12 Stator 12 (A1), 12 (A2), 12 (B1), 12 (B2), 12 (C1), 12 (C2) Stator tooth portion 14 (A1) coil (A1 coil)
14 (A2) coil (A2 coil)
14 (B1) coil (B1 coil)
14 (B2) coil (B2 coil)
14 (C1) coil (C1 coil)
14 (C2) coil (C2 coil)
16 Rotor 16 (R1), 16 (R2), 16 (R3), 16 (R4) Rotor teeth 18, 22 Three-phase reluctance motor controller 20 (A1), 20 (A2), 20 (B1), 20 (B2), 20 (C1), 20 (C2) drive circuit (full bridge type PWM inverter)
24 (1) to 24 (6) 1st to 6th arms (PWM inverter)
ia1, ia2, ib1, ib2, ic1, ic2 drive current
Reference value of Tth rotational torque

Claims (4)

A plurality of stator teeth are projected on the inner peripheral surface of the cylinder, and a stator in which a coil is wound around each stator tooth is arranged coaxially inside the stator, and a plurality of stators are arranged on the outer peripheral surface. In the control method of a three-phase reluctance motor equipped with a rotor having a protruding rotor tooth portion.
The plurality of coils are divided into k sets (k is a natural number) of A1 coils and A2 coils, k sets (k is a natural number) of B1 coils and B2 coils, and k sets (k is a natural number) of C1 coils and C2 coils. Then, the k sets are arranged at equal intervals in the order of A1, B2, C1, A2, B1, and C2 in the circumferential direction of each of the coils.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized in opposite polarities at the same timing, and the drive currents are supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized in opposite polarities at the same timing, and the C1 and C2 coils are wound around the C1 and C2 coils. A first operation mode in which the three-phase reluctance motor is operated as a switch reluctance motor by supplying a driving current so that the stator teeth are magnetized in opposite polarities at the same timing.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized to the same polarity at the same timing, and the drive current is supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized at the same timing and with the same polarity, and the C1 and C2 coils are wound around the C1 and C2 coils. A second operation mode for operating the three-phase reluctance motor as a synchronous reluctance motor is set by supplying a drive current so that the stator teeth are magnetized at the same timing and with the same polarity. ,
When the rotational torque of the rotor is equal to or higher than the reference value, the three-phase reluctance motor is operated in the first mode, and when it is less than the reference value, the three-phase reluctance motor is operated in the second mode. A control method for a three-phase reluctance motor. A plurality of stator teeth are projected on the inner peripheral surface of the cylinder, and a stator having a coil wound around each of the stator teeth and a plurality of stators arranged coaxially inside the stator and on the outer peripheral surface. In a three-phase reluctance motor control device that controls the operation of a three-phase reluctance motor including a rotor having a protruding rotor tooth portion.
The plurality of coils are divided into k sets (k is a natural number) of A1 coils and A2 coils, k sets (k is a natural number) of B1 coils and B2 coils, and k sets (k is a natural number) of C1 coils and C2 coils. Then, the k sets are arranged at equal intervals in the order of A1, B2, C1, A2, B1, and C2 in the circumferential direction of each of the coils.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized in opposite polarities at the same timing, and the drive currents are supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized in opposite polarities at the same timing, and the C1 and C2 coils are wound around the C1 and C2 coils. A first operation mode in which the three-phase reluctance motor is operated as a switch reluctance motor by supplying a driving current so that the stator teeth are magnetized in opposite polarities at the same timing.
A drive current is supplied to the A1 and A2 coils so that the stator teeth around which the A1 and A2 coils are wound are magnetized to the same polarity at the same timing, and the drive current is supplied to the B1 and B2 coils. A drive current is supplied so that the stator teeth around which the B1 and B2 coils are wound are magnetized at the same timing and with the same polarity, and the C1 and C2 coils are wound around the C1 and C2 coils. A second operation mode for operating the three-phase reluctance motor as a synchronous reluctance motor is set by supplying a drive current so that the stator teeth are magnetized at the same timing and with the same polarity. ,
When the rotational torque of the rotor is equal to or higher than the reference value, the three-phase reluctance motor is operated in the first mode, and when it is less than the reference value, the three-phase reluctance motor is operated in the second mode. A three-phase reluctance motor control device characterized by this. It is provided with six full-bridge type PWM inverters that individually drive the A1 coil, the A2 coil, the B1 coil, the B2 coil, the C1 coil, and the C2 coil.
The three-phase reluctance motor control device according to claim 2, wherein the first and second operation modes are switched by changing the switching sequence of each of the full-bridge type PWM inverters. It has first to sixth arms composed of a series circuit of two switching elements, and the A1 coil and the A2 coil are located between the middle point of the first arm and the middle point of the second arm. A series circuit is connected, and a series circuit of the B1 coil and the B2 coil is connected between the midpoint of the third arm and the midpoint of the fourth arm, and the midpoint of the fifth arm. A series circuit of the C1 coil and the C2 coil is connected between the and the middle point of the sixth arm, and the connection point of the A1 and A2 coils, the connection point of the B1 and B2 coils, and the C1 and C2. A PWM inverter for driving each coil in a state where the connection points of the coils are connected to each other is provided.
The three-phase reluctance motor control device according to claim 2, wherein the first and second operation modes are switched by changing the switching sequence of the PWM inverter.

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