JPH11136984A - Conduction controller for switched reluctance motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size and cost of an SR motor while satisfying the ratings. SOLUTION: This conduction controller comprises temperature sensors 5a-5c for coils 1a-1c, and a temperature sensor 6 for the stator core. Under a situation where the coils 1a-1c are not damaged by heat, the motor is controlled to conduct the coils 1a-1c with high efficiency. Under a situation where the coils 1a-1c may be damaged by heat, conduction the of the coils 1a-1c motor is controlled to suppress heating thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an energization control device for a switched reluctance motor.

[0002]

2. Description of the Related Art Switched reluctance motors (hereinafter referred to as "reluctance motors")
An SR motor) is generally provided with a rotor configured with poles protruding outward and a stator configured with poles protruding inward. The stator is a core formed by laminating iron plates, and the stator includes a copper coil that is concentratedly wound on each pole of an annular core formed by laminating a large number of iron plates. In this SR motor, each pole of the stator operates as an electromagnet, and the rotor rotates by attracting each pole of the rotor with the magnetic force of the stator. Therefore, the rotor is rotated in a desired direction by sequentially switching the energized state of the coils wound around the respective poles of the stator according to the rotation position (rotation angle of the rotor) of each pole of the rotor. Can be done.

[0003] The prior art relating to this kind of SR motor is as follows.
For example, it is disclosed in JP-A-1-298940. As disclosed in this publication, a general method of energizing the coil is to energize each phase for a period of π in electrical angle and then advance the phase according to the motor speed. It is. Further, as a development of the method, there is a method of controlling the energization timing map according to the number of rotations of the motor and the required torque for the main purpose of high-efficiency operation, which is disclosed in, for example, JP-A-7-274570.

[0004]

The loss in the SR motor is roughly divided into three components. The first loss component is a copper loss generated by the electric resistance of the coil, the second loss component is an iron loss generated by magnetic flux passing through the iron core of the rotor and the stator, and a third loss component. Is the mechanical loss due to the friction between the rotor and the bearing of the drive shaft, which is overwhelmed. Looking at the breakdown of losses, copper loss accounts for a high percentage in the low speed range, and iron loss and mechanical loss percentages are high in the high speed range.

When the SR motor outputs a high torque, most of the loss is occupied by copper loss, and the temperature of the coil rises in a very short time. If the temperature of the coil rises too much, the insulation of the wire of the coil will be damaged. In order to satisfy the thermal rating of the SR motor, measures such as increasing the heat capacity of the coil and reducing copper loss by increasing the size of the SR motor are generally taken. It will be expensive.

An object of the invention of this application is to make the SR motor smaller and less expensive than the prior art in satisfying the thermal rating.

[0007]

The invention according to claim 1 of the present application includes means for detecting the rotation angle of a rotor having a plurality of magnetic poles, and each magnetic pole of the stator according to the rotation angle of the rotor. In a control device for a switched reluctance motor, which sequentially switches on / off the energization of a coil wound around a coil, a temperature sensor for detecting a temperature of the coil, and a temperature of the coil detected by the temperature sensor is determined by heat. If the temperature is below the predetermined temperature at which there is no risk of damage, the energization ON angle, energization OFF angle and current target value for the coil are set to the predetermined values for high-efficiency driving, and the coil temperature exceeds the predetermined temperature. A switching reluctance mode, comprising: an energization angle switching means for switching the energization on angle, energization off angle, and current target value to a predetermined value for reducing coil heat generation. Which is a control device.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

The device shown in FIG. 1 constitutes a main part of a drive unit of an electric vehicle. In this device, one SR motor 1 is provided as a drive source, and this SR motor 1 is controlled by a controller ECU. The controller ECU includes a shift lever, a brake switch (brake SW), and an accelerator switch (accelerator SW).
And the drive of the SR motor 1 is controlled based on information input from the accelerator opening sensor. The control power is supplied from a battery.

FIG. 3 shows the basic configuration of the SR motor 1 and its driving principle. The SR motor 1 shown in FIG.
And a rotor R rotatably supported in the inner space thereof. The rotor R is formed by laminating a large number of thin iron plates.
Four pole parts Ra, Rb, Rc and Rd protruding outward are formed. The stator S is also formed by laminating a large number of thin iron plates, and has six poles Sa, S protruding inward at positions shifted from each other by 60 degrees on the inner circumference.
b, Sc, Sd, Se and Rf are formed. FIG.
Although only a part is shown in FIG.
A coil CL is wound around each of a, Sb, Sc, Sd, Se and Rf.

Here, the coil CL wound around the pole portions Sa and Sd of the stator S is in the first phase, the coil CL wound around the pole portions Sb and Se is in the second phase, and the coil CL is wound around the pole portions Sc and Sf. Coil C
When L is defined as a third phase, the first phase is determined according to the rotation position of the pole of the rotor R (the rotation angle of the rotor R), as shown in FIG.
By sequentially energizing the phase-second-phase-third-phase coil CL, the rotor R can be continuously driven to rotate clockwise. That is, since the energized pole portion of the stator S forms an electromagnet, the pole portion of the rotor R at a rotational position close to the electromagnet is attracted by the electromagnet and rotates. In order to continue the rotation, the coil C
It is necessary to switch the energization of L. Actually, in the case of the SR motor 1, the coil CL to be energized may be switched from the first phase to the second phase to the third phase every time the rotor R rotates by 30 degrees.

The description will be continued with reference to FIG. The SR motor 1 has a three-phase coil 1a for driving it,
1b, 1c, an angle sensor 1d for detecting the rotation angle of the rotor R, and a speed sensor 1 for detecting the rotation speed of the rotor R
e is provided. Three-phase coils 1a, 1b and 1c
Are the drivers 18 and 1 in the controller ECU, respectively.
9 and 1A, the coil 1a and the driver 1
Current sensors 2, 3 and 4 are provided on a signal line connecting the coil 1b, the coil 1b and the driver 19, and a signal line connecting the coil 1c and the driver 1A, respectively. These current sensors 2, 3 and 4 have
Each outputs a voltage proportional to the current actually flowing through the coils 1a, 1b and 1c as a current signal S6. Further, temperature sensors 5a, 5b and 5c for detecting the temperatures of the coils 1a, 1b and 1c and a temperature sensor 6 for detecting the temperature of the annular core (or motor housing) of the stator S are provided. I have. These temperature sensors 5a, 5b,
The detection output of 5c and 6 is the C output inside the controller ECU.
It is input to a PU (microcomputer) 11.

A CPU 1 is provided inside the controller ECU.
1, input interface 12, current map memory 13a for normal drive, current map memory 13b for coil heat reduction drive, power supply circuit 14, current waveform generation circuit 15, comparison circuit 16, output determination circuit 17, drivers 18, 19, and 1A is provided. The controller ECU sequentially calculates a drive rotation speed and a drive torque of the SR motor 1 based on information input from a shift lever, a brake switch, and an accelerator opening sensor, and based on the calculation result, based on the calculation result. Of the coils 1a, 1b, and 1c.

FIG. 2 shows a specific configuration of a main part of the circuit shown in FIG. FIG. 2 shows only a circuit for controlling the energization of the coil 1a of the SR motor 1, and in practice, the other coils 1a
Similar circuits for controlling the energization of b and 1c, respectively, are included.

Referring to FIG. 2, one end of the coil 1a is
The other end of the coil 1a is connected via a switching transistor (IGBT) 18b to the low potential line 18f of the power supply via a switching transistor (IGBT) 18b. Further, the emitter of the transistor 18a and the low potential line 18
The diode 18c is connected between the transistor 18f and the diode 18c, and the diode 18d is connected between the emitter of the transistor 18d and the high potential line 18e. Therefore, if both the transistors 18a and 18b are turned on (conducting state), a current flows between the power supply lines 18e and 18f and the coil 1a, and one or both of them are turned off (non-conducting state).
, The energization of the coil 1a can be stopped.

The output determination circuit 17 has two AND gates 17a and 17b. AND gate 17a
Is connected to the gate terminal of the transistor 18b, and the output terminal of the AND gate 17b is connected to the gate terminal of the transistor 18a. The signals S72 and S5 are input to the input terminal of the AND gate 17a, and the signals S71 and S72 are input to the input terminal of the AND gate 17b.
And S5 are input. The signals S71 and S72 are binary signals output from the analog comparators 16a and 16b of the comparison circuit 16, respectively. The signal S5 is a binary signal output from the current waveform generation circuit 15.

The comparison circuit 16 includes two analog comparators 16
a and 16b. The analog comparator 16a is
First reference voltage Vr1 output from current waveform generation circuit 15
And outputs the result of comparing the voltage of the signal S6 corresponding to the current detected by the current sensor 2 as a binary signal S71. The analog comparator 16b compares the second reference voltage Vr2 output by the current waveform generation circuit 15 with the second reference voltage Vr2. The comparison result of the voltage of the signal S6 corresponding to the current detected by the current sensor 2 is output as a binary signal S72. In this embodiment, Vr1 is always
The relationship of <Vr2 holds.

When the signal S5 is at a high level H, the signal S6
According to the magnitude relationship between the voltage Vs6 and the reference voltages Vr1 and Vr2, the states of the transistors 18a and 18b of the driver 18 are set to one of three types as shown below.
That is, when Vs6 <Vr1, the signals S71 and S72 are both at the high level H, so that the AND gates 17a and 17
b becomes high level H, and the transistors 18a,
8b are both turned on. When Vr1 <Vs6, the signal signals S71 and S72 are both at the low level L, so that the outputs of the AND gates 17a and 17b are at the low level,
The transistors 18a and 18b are both turned off. Vr1
When <Vs6 <Vr2, the signal S71 goes low and the signal S72 goes high, so the output of the AND gate 17a goes high and the AND gate 1
The output of 7b goes low, the transistor 18a turns off and the transistor 18b turns on.

That is, there are a state in which the transistors 18a and 18b are both turned on, a state in which both are turned off, and a state in which one is turned on and the other is turned off. Less than Vr1, Vr1 and Vr2
Is determined depending on which of the three types of regions is larger than Vr2.

When the signal S5 is at the low level L, the outputs of the AND gates 17a and 17b are always at the low level regardless of the state of the signals S71 and S72 output from the comparison circuit 16, and the transistors 18a and 18b Are both turned off.

The rise characteristic (speed of rise) of the current flowing through the coil 1a when both the transistors 18a and 18b are turned on is determined by the time constant of the circuit and cannot be changed by control. However, when cutting off the current, the speed of the current falling can be adjusted by turning off both the transistors 18a and 18b and by turning off the transistor 18a and keeping the transistor 18b on. it can. That is, the transistors 18a, 18
When both transistors b are turned off, the current changes rapidly. When the transistor 18a is turned off and the transistor 18b remains on, the current changes slowly.

When there is almost no change in the current target values (Vr1, Vr2), even if the current falls slowly,
Since the deviation between the reference level (Vr1) and the level of the actually flowing current (Vs6) does not increase, it is always V
The state of s6 <Vr2 is maintained. So at this time,
Current fluctuation is small. Further, when the current target values (Vr1, Vr2) are changed, such as when the phase of a coil to be energized is changed, if the fall speed of the current is slow, Vs
6> Vr2. In this case, two transistors 18
Since both a and 18b are turned off, the falling speed of the current increases, and the current changes quickly following the target values (Vr1, Vr2). If the change in the target value stops, the deviation between the reference voltage Vr1 and the current level Vs6 decreases,
Again, the fall speed of the current becomes slow.

This not only prevents the delay of the current following the change in the target value, but also suppresses the generation of vibration and noise when the change in the target value is small, because the change speed of the current is slow. When the fall speed of the current is switched by the signals S71 and S72 output from the comparison circuit 16 shown in FIG. 2, the actual switching tends to be slightly delayed from the optimal timing as the switching timing. That is, when the target value sharply drops, it is ideal to make the current fall faster. However, if the current deviation does not actually increase, the signal S72 does not go to the low level L, so that the time is delayed. Occurs. For this reason, when the target value changes very quickly, there is a possibility that the responsiveness of the current to the target value is insufficient only by the automatic switching of the change speed by the signals S71 and S72.

Therefore, in this embodiment, by controlling the signal S5, the falling speed of the current can be increased irrespective of the magnitude of the current (Vs6). That is, when the signal S5 is set to the low level L, the signals S71, S7
Irrespective of 2, since the transistors 18a and 18b are turned off at the same time, the fall speed of the current is increased.

Referring to FIG. 2, current waveform generating circuit 15
Outputs two kinds of reference voltages Vr1 and Vr2 and a binary signal S5. Reference voltages Vr1, Vr2 and binary signal S5
Are the memories (RAM) 15b, 15a and 15c, respectively.
Is generated based on the information stored in the. Memory 15
b, 15a, and 15c hold 8-bit, 8-bit, and 1-bit data at each address. The 8-bit data read from the memory 15a is D / A
The signal is converted into an analog signal by the converter 15e, and the
To the reference voltage Vr2. Similarly, the memory 15b
Is read from the D / A converter 15
The signal is converted into an analog signal by f and becomes the reference voltage Vr1 through the amplifier 15h. The level of the analog signal S1 output from the CPU 11 is added to the inputs of the amplifiers 15g and 15h. By adjusting the level of the signal S1, the reference voltages Vr1 and Vr2 can be finely adjusted. The 1-bit data output from the memory 15c is
The signal S5 passes through the AND gate 15i. One of the input terminals of the AND gate 15i is connected to the CPU output 2
A value signal (start / stop signal) S3 is applied.
When the SR motor 1 is being driven, the signal S3 is always at the high level H, so that the output signal of the memory 15c becomes the binary signal S5 as it is.

Each of the memories 15a, 15b and 15c has a large number of addresses, and each address is associated with each of the rotation angles of the rotor R (in units of one degree). The address decoder 15d generates address information from the rotation angle signal S9 of the rotor R detected by the angle sensor 1d. This address information is simultaneously input to the address input terminals of the three sets of memories 15a, 15b and 15c. Therefore, when the SR motor 1 rotates, the memories 15a, 15b, and 15c sequentially output data held at addresses corresponding to the respective rotation angles. Therefore, the reference voltages Vr1, Vr2 and the binary signal S5
Can change for each rotation angle.

Actually, in order to allow a current having a waveform as shown in FIG. 4 to flow through the three-phase coils, the memories 15a and 15b hold information of an energization map as shown in FIG. 8, respectively. That is, the target value of the current to be set at that position is held at the address associated with each of the rotation angles (in this example, every 0.5 degrees). The information in the memories 15a and 15b is
Since they correspond to the reference voltages Vr2 and Vr1, respectively,
The contents of the memory 15a and the contents of the memory 15b are slightly different so as to satisfy the relationship of r2> Vr1. As described above, since the level of the current flowing through the coil 1a changes so as to follow the reference voltage Vr1, the waveform of the current desired to flow through the coil 1a is registered in the memories 15a and 15b as the reference voltages Vr1 and Vr2. This allows a current to flow as shown in FIG.

In this embodiment, three-phase coils 1a, 1
It is necessary to switch energization / non-energization for b and 1c every time the rotor R rotates 30 degrees as shown in FIG.
By registering the waveforms as shown in FIG. 4 in the memories 15b and 15a, switching between energization and non-energization at every 30 degrees is automatically performed by the signals S71 and S72. That is, there is no need for the CPU 11 to switch the energization / non-energization of each coil.

In the memory 15c, information of "1" corresponding to the high level H of the signal S5 is held at most of the addresses, but the target values of the currents (Vr1, Vr
The information corresponding to the low level L of the signal S5 (0) (forcible cutoff information) is held in the address corresponding to the angle at which 2) sharply decreases. That is, the target value of the current (Vr
At the rotation angle at which the falling slope is steep, such as at the start of the fall of the waveform of (1, Vr2), and where it is expected that the current change rate should be increased, the automatic switching by the signal S72 is awaited. Instead, the signal S5 is switched to the low level L according to the information stored in the memory 15c, and the current change speed is forcibly increased. As a result, it is possible to avoid a time delay in switching the current change speed, and the follow-up of the current to the target value is further improved.

The memories 15a, 15b and 15c are capable of writing and reading, and can execute writing and reading simultaneously. The memories 15a, 15b and 15c
It is connected to the CPU 11 via the signal line S2,
U11 stores the memories 15a, 15b and 15 as necessary.
Update the contents of c.

FIG. 5 schematically shows the operation of the CPU 11. The operation of the CPU 11 will be described with reference to FIG. When the power is turned on, initialization is executed in step 61. That is, CP
After the initialization of the internal memory of U11 and the mode setting such as the internal timer and the interrupt, the system is diagnosed, and if there is no abnormality, the process proceeds to the next processing.

In step 62, a shift lever, a brake switch, an accelerator switch, an accelerator opening sensor, a temperature sensor 5a,
5b, 5c and 6 read the state of each of the signals respectively output and store the state in the internal memory.
Proceed to 3.

In step 63, the current map memory 13a and the current map memory 13b are selected based on the coil temperature detected in step 62 and the core temperature of the stator S. For example, if the temperature of the coils 1a, 1b and 1c is lower than a predetermined temperature at which the coil is not likely to be damaged by heat and the temperature of the core of the stator S is lower than a predetermined temperature at which there is a thermal margin, step 64 is performed. After resetting the current map switching flag, the routine proceeds to step 66. Resetting the current map switching flag means that the high efficiency driving current map memory 13a has been selected to perform high efficiency operation. If the temperatures of the coils 1a, 1b and 1c are higher than the predetermined temperature and the temperature of the core of the stator S is lower than the predetermined temperature at which there is a thermal margin, the current map switching flag is set at step 65. After that, step 66
Proceed to. The setting of the current map switching flag means that the current map memory 13b for driving to reduce coil heat is selected. Even if the temperatures of the coils 1a, 1b, and 1c exceed the predetermined temperature, if the core temperature of the stator S exceeds the predetermined temperature, the current map switching flag is not set.

In step 66, it is checked whether or not there is any change in the state of each output of the shift lever, brake switch, accelerator switch, and accelerator opening sensor detected in step 62, and if there is any change, Proceed to step 67, and if there is no change, proceed to step 68. In step 67, the SR motor 1 is controlled based on the various states detected in step 62.
Is determined. For example, when the accelerator opening detected by the accelerator opening sensor increases, the target value of the driving torque increases. Here, a torque change flag indicating a change in the target torque is set.

In step 68, the rotation speed of the SR motor is detected. In this embodiment, the speed sensor 1e connected to the output shaft of the SR motor 1 outputs a pulse signal whose cycle changes according to the rotation speed of the output shaft. CPU11
Measures the pulse cycle output by the speed sensor 1e, and detects the rotation speed of the SR motor 1 based on this cycle.
The detected rotation speed data is stored in the internal memory. Next, at step 69, it is checked whether or not the rotation speed of the SR motor 1 has changed.

When there is a change in the rotation speed of the SR motor 1, the process proceeds to step 71, and when there is no change in the rotation speed, the process proceeds to step 70. In step 70, the state of the torque change flag is checked. When the flag is set, that is, when there is a change in the target torque, the process proceeds to step 71, and when there is no change in the target torque, the process returns to step 62.

In step 71, the state of the current map switching flag is checked, and if it is not set, data is inputted from the current map memory 13a, and if it is set, data is inputted from the current map memory 13b. In this embodiment, the current map memories 13a and 13b are constituted by read-only memories (ROM) in which various data are registered in advance, and the current map memories 13a and 13b store data as shown in FIGS. Is held.

That is, in the current map memory 13a, the SR
A large number of data Cnm (n: n: n) corresponding to various target torques and various rotation speeds (rotation speeds) of the motor 1 respectively.
The numerical value in the column corresponding to the torque, m: the numerical value in the row corresponding to the rotation speed) is held as the current map 1 and the data C
One set of nm includes a power-on angle, a power-off angle, and a current target value. For example, if the torque is 50 [N ·
m] and the rotation speed is 3000 [rpm].
Are 41 degrees, 62 degrees and 200 [A]. That is, within the range of the rotation angle of 0 to 90 degrees, a current of 200 [A] is passed through the specific coil in the range of 41 to 62 degrees, and the current is passed in the range of 0 to 41 degrees and the range of 62 to 90 degrees. It means to shut off. In step 71, a set of Cnm data selected according to the torque and the rotation speed at that time is input.

The current map memory 13b stores the SR
A large number of data Dnm (n: n: n) corresponding to various target torques and various rotation speeds (rotation speeds) of the motor 1 respectively.
The numerical value in the column corresponding to the torque, m: the numerical value in the row corresponding to the rotation speed) is held as the current map 2 and the data D
One set of nm includes a power-on angle, a power-off angle, and a current target value. For example, if the torque is 50 [N ·
m] and the rotation speed is 3000 [rpm].
Are 44 degrees, 68 degrees, and 160 [A]. That is, within the range of the rotation angle of 0 to 90 degrees, a current of 160 [A] is applied to the specific coil in the range of 44 to 68 degrees, and the current is supplied in the range of 0 to 44 degrees and 68 to 90 degrees. It means to shut off. In step 71, a set of data of Dnm selected according to the torque and the rotation speed at that time is input.

FIG. 8 shows the difference between the current waveform based on the current map 1 and the current waveform based on the current map 2. As shown in FIG. When the target torque and the number of revolutions are the same, the energization ON angle and the energization OFF angle in the current map 2 are later than the energization ON angle and the energization OFF angle in the current map 1. Is smaller than the target current value in the current map 1.

In step 6A of FIG. 5, based on the data inputted in step 71, data of an energization map as shown in FIG. 8 is generated, and the memory of the current waveform generation circuit shown in FIG. 15a, 15b, 1
5c is updated (rewritten). Of course, not only is the energization map written in the memories 15a, 15b, and 15c for one phase shown in FIG. 2, but energization maps are created for all three phases of memory, and the data is written to each memory. In this embodiment, as shown in FIG. 9, the current value of each phase is registered in the energization map every 0.5 degree of the rotation angle of the rotor R. As described above, the memories 15a, 15
Since the current flowing through the coil 1a is controlled based on the data of b and 15c, the CPU 11
a, 15b, 15c) only by writing the energization map,
Accordingly, the excitation switching of each coil is automatically performed by a hardware circuit.

FIG. 10 shows the relationship between the efficiency of the SR motor and the power-off angle when the rotational speed is 3000 [rpm] -torque 50 [N · m]. FIG. 11 shows that the number of rotations is 3000 [rpm].
m] -shows the relationship between the copper loss and iron loss at a torque of 50 [N · m] and the energization off angle. FIG.
The relationship between each temperature of the coil, the stator core, and the output shaft at 0 [rpm] -torque 50 [N · m] and the energization off angle is shown. As shown in FIG. 10, the efficiency of the SR motor changes with a change in the power-off angle, and also changes with a change in the power-on angle. The energization ON angle and the energization OFF angle in the current map 1 are selected so as to maintain high efficiency, and as described above, the coils 1a, 1b, and 1
If c is not higher than a predetermined temperature at which the coil is not likely to be damaged by heat, and if the core temperature of the stator S is not higher than a predetermined temperature at which there is a thermal margin, the coils 1a, 1b and 1
Since the energization to c is controlled based on the current map 1,
The SR motor 1 is operated with high efficiency.

When the temperature of the coils 1a, 1b and 1c exceeds a predetermined temperature and the temperature of the core of the stator S is lower than a predetermined temperature at which there is a thermal margin, the coils 1a, 1b and 1c
The energization of 1b and 1c is controlled based on the current map 2. The energization ON angle and the energization ON angle in the current map 2 are delayed from the energization ON angle and the energization ON angle in the current map 1, and the target current value in the current map 2 is set smaller than the target current value in the current map 1. And these values are selected so that the temperature of the coil becomes the lowest. By making the energization ON angle and the energization OFF angle later than the energization ON angle and the energization OFF angle at which high efficiency is obtained, copper loss is reduced (see FIG. 11).
In conjunction with the reduction of the target current value, the temperature rise of the coils 1a, 1b and 1c is suppressed, and the coils 1a, 1b
And 1c are suppressed. At this time, as shown in FIG. 11, the iron loss increases, and the iron core of the stator S and the rotor R
However, there is no problem because the motor housing surrounding the stator S generally has a heat radiation structure.

When the current map 1 and the current map 2 are selected, the rate of change of the coil temperature is monitored, and even if the coil temperature is lower than the predetermined temperature, the energization based on the current map 1 is continued for a predetermined time. When the coil temperature is predicted to exceed the predetermined temperature later, the current map 1 may be switched to the current map 2.

Further, the method of obtaining the energization ON angle, the energization OFF angle, and the target current value for the coil is performed without using a map.
It may be calculated.

[0046]

As described above, the invention of this application detects the temperature of the coil of the SR motor, and in a situation where there is no fear that the coil will be damaged by heat, the power supply to the coil can be performed with high efficiency. In a situation in which the coil is damaged due to heat, the energization of the coil is controlled so as to reduce the heat generation of the coil. The motor can be reduced in size and cost.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed configuration of a part of FIG.

FIG. 3 is a diagram showing a basic configuration and operation of an SR motor.

FIG. 4 is a time chart illustrating a waveform example of an excitation current instruction when driving an SR motor.

FIG. 5 is a flowchart illustrating an operation of a CPU 11;

FIG. 6 is a map showing the contents of a current map memory 13a.

FIG. 7 is a map showing the contents of a current map memory 13b.

FIG. 8 is a diagram showing a difference in a current waveform of energization based on a current map 1 and a current map 2 in current map memories 13a and 13b.

FIG. 9 is a map showing the contents of an energization map memory.

FIG. 10 is a diagram showing the relationship between the efficiency of the SR motor and the energization off angle.

FIG. 11 is a diagram showing a relationship between a copper loss and an iron loss and an energization off angle.

FIG. 12 is a diagram showing a relationship between each temperature of a coil, a stator core, and an output shaft and an energization ON angle.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... SR motor 1a, 1b, 1c, CL ... Coil 1d ... Angle sensor 1e ... Speed sensor 5a, 5b, 5c, 6 ... Temperature sensor ECU ... Controller 11 ... CPU 12 ... Input interface 13a, 13b ... Current map memory 14 ... Power supply circuit 15 ... Current waveform generation circuit 15a, 15b, 15c ... Memory 15d ... Address decoder 15e, 15f ... D / A converter 15g, 15h Amplifier 16 Comparison circuit 16a, 16b Analog comparator 17 Output determination circuit 18, 19, 1A, 18a, 18b Transistor (IGBT) 18c, 18d: Diodes 18e, 18f: Power line R: Rotor S: Stator: Ra to Rd, Sa to Sf: Part

Claims (1)

[Claims] An apparatus includes means for detecting a rotation angle of a rotor having a plurality of magnetic poles, and sequentially switches on / off of energization of coils wound around respective magnetic poles of a stator in accordance with the rotation angle of the rotor. In the control device for the switched reluctance motor, a temperature sensor for detecting the temperature of the coil, and if the temperature of the coil detected by the temperature sensor is equal to or lower than a predetermined temperature at which the coil is not likely to be damaged by heat, The energizing ON angle, energizing OFF angle and current target value for the coil are set to predetermined values for high-efficiency driving. When the coil temperature exceeds a predetermined temperature, the energizing ON angle, energizing OFF angle and current target value for the coil are set. A control device for a switched reluctance motor, comprising: an energization angle switching means for switching a value to a predetermined value for reducing coil heat generation.