JP2008104267A - Motor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor device for which the initial position of a rotor in its stop state can be easily estimated, and which can be started stably, based on the estimated initial position of the rotor. <P>SOLUTION: The motor device applies the same voltage pulses to the coils Lu, Lv and Lw of each phase of the stator 2 of a motor part 10 from an inverter part 22 by an inverter controller 23a when starting its motor part 10 from the stop state of the motor part which has a stator 2 that has a plurality of salient poles where the coils Lu, Lv and Lw are wound separately for each phase and a rotor 1 that has a plurality of salient poles. During application of this voltage pulses, a rotational position fixer 23d fixes the rotational position of the rotor 1 to the stator 2, based on the current deviation of the current flowing to the coils Lu, Lv and Lw of each phase detected by current sensors CTu, CTv and CTw. It starts the motor part 10 by controlling the inverter part 22 so that it may output voltage to rotate the rotor 1, based on the fixed rotational position of the rotor 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a motor device, and more particularly to a motor device that controls rotation of a motor unit such as a switched reluctance motor by an inverter unit.

  Conventionally, as a motor device, a rotor having a plurality of teeth is used without using a permanent magnet, and when a direct current flows through the stator coil, the magnetic pole is excited, and the rotor tooth becomes the stator magnetic pole. Some inverters control rotation of a switched reluctance motor that rotates by being attracted.

  In a motor device that controls the rotation of such a switched reluctance motor using an inverter, it is necessary to apply an optimum current according to the position of the rotor to a coil provided in the stator. Therefore, in order to accurately know the position of the rotor relative to the stator, it may be possible to attach an optical or magnetic position sensor to the rotor shaft. However, the reference position of the position sensor is fixed when starting from a stopped state. In this case, there is a problem that it is not known from which phase the commutation at the start is started.

Thus, a method for estimating the rotor position from the relative magnetic characteristics of the rotor and the stator has been proposed (see, for example, Japanese Patent Application Laid-Open No. 2004-336865 (Patent Document 1)). However, this rotor position identification method is complicated in calculation processing, and the calculation processing time of the control microcomputer must be sufficiently high for high-precision identification, leading to an increase in system cost. There is a problem.
JP 2004-336865 A

  Accordingly, an object of the present invention is to easily estimate the initial position of the rotor in a stopped state of a motor unit such as a switched reluctance motor, and to perform stable startup based on the estimated initial position of the rotor. The object is to provide a motor device.

In order to solve the above problems, the motor device of the present invention is:
A stator having a plurality of salient poles each having a coil wound for each phase, and a plurality of rotors rotated by magnetic attraction generated on the salient poles of the stator by supplying current to the coils of the stator. A motor unit having a rotor having salient poles;
An inverter unit for applying a voltage to the coils of each phase of the stator of the motor unit;
A current detection unit for detecting current flowing from the inverter unit to the coils of the respective phases of the stator of the motor unit;
The inverter unit is controlled based on the current flowing through the coils of the respective phases of the motor unit detected by the current detection unit, and when the inverter of the motor unit is started from the stopped state, the inverter An inverter control unit for simultaneously applying the same voltage pulse to each phase coil of the stator of the motor unit from the unit;
The rotational position of the rotor relative to the stator is identified based on the current flowing through the coils of the phases of the motor unit detected by the current detection unit when the same voltage pulse is applied from the inverter unit. A rotational position identification unit,
Based on the rotation position of the rotor relative to the stator identified by the rotation position identification unit, the inverter control unit controls the inverter unit to output a voltage for rotating the rotor, and the motor The unit is activated.

  According to the motor device having the above configuration, when starting from the stopped state of the rotor of the motor unit, the inverter control unit controls the inverter unit, and from the inverter unit to the coils of each phase of the stator of the motor unit. The same voltage pulse is applied simultaneously. If it does so, a coil current will increase in the area which applied the voltage pulse, and the coil current of each phase will flow according to the coil resistance and inductance of the phase. At this time, assuming that the coil resistance of each phase is equal, an inductance that varies depending on the rotational position of the rotor appears as a difference in the coil current of each phase. Accordingly, the rotational position identifying unit can identify the rotational position of the rotor with respect to the stator based on the currents flowing through the coils of the respective phases of the motor unit during application of the same voltage pulse. In this way, the inverter unit is controlled by the inverter control unit so as to estimate the initial position of the rotor when the motor unit is stopped and to output a voltage for rotating the rotor based on the initial position of the rotor. Start the motor. Therefore, when the motor unit is stopped, the initial position of the rotor can be easily estimated without performing complicated calculation processing, and stable startup can be performed based on the estimated initial position of the rotor. Here, the motor unit includes a switched reluctance motor and a variable reluctance type stepping motor.

Moreover, in the motor device of one embodiment,
A current deviation unit for obtaining a current deviation of a current flowing in the coils of the respective phases detected by the current detection unit when the same voltage pulse is applied from the inverter unit;
Based on the current deviation obtained by the current deviation unit, the rotational position identification unit identifies the rotational position of the rotor with respect to the stator.

  According to the embodiment, when the same voltage pulse is applied from the inverter unit, the current deviation of the current flowing through the coils of each phase detected by the current detection unit is obtained by the current deviation unit. For example, the current deviation of the coil current that increases in a predetermined interval during application of the voltage pulse and the inductance of the coil of each phase have a substantially inversely proportional relationship in a very short period compared to the coil time constant. Therefore, the phase with a smaller current deviation has a larger inductance of the coil of the phase, and the salient pole of the rotor is closer to the salient pole of the stator around which the coil of the phase is wound. Using such a relationship, the rotational position identification unit can easily identify the rotational position of the rotor relative to the stator based on the current deviation of the current flowing through the coils of each phase obtained by the current deviation unit. Can do.

Moreover, in the motor device of one embodiment,
Immediately before and immediately after applying the same voltage pulse from the inverter unit, the current detection unit detects the current flowing through the coils of the respective phases of the stator once,
A deviation between two currents for each phase detected by the current detection unit is obtained by the current deviation unit as the current deviation.

  According to the above embodiment, immediately before and after applying the same voltage pulse from the inverter unit, the current detection unit detects the current flowing through the coils of the respective phases of the stator once, and detects the current. The deviation of the two currents for each phase detected by the unit is obtained by the current deviation unit as the current deviation. As a result, the influence of the switching noise of the inverter unit at the time of detecting the current flowing in the coils of each phase is reduced, and the current detection accuracy is improved, thereby improving the estimation accuracy of the rotor position.

Moreover, in the motor device of one embodiment,
During the period of applying the same voltage pulse from the inverter unit, the current detection unit periodically detects the current flowing in the coils of the respective phases of the stator a plurality of times,
The current deviation is obtained by the current deviation unit based on a plurality of currents for each phase detected by the current detection unit.

  According to the above embodiment, during the period when the same voltage pulse is applied, the switching element of the inverter unit is turned on without switching, and the current flowing through the coils of each phase of the stator is periodically Based on the plurality of currents detected for each phase and detected by the current detection unit for each phase, the current deviation unit obtains the current deviation of the current flowing through the coil of each phase. By doing so, it is not affected by the switching of the inverter unit, so that the current deviation can be detected with high accuracy.

Moreover, in the motor device of one embodiment,
The inverter control unit repeats the application of the same voltage pulse from the inverter unit a plurality of times, and the current deviation unit obtains an average value of a plurality of current deviations obtained for each application of the same voltage pulse. Seeking
Based on the average value of the plurality of current deviations obtained by the current deviation unit, the rotational position identification unit identifies the rotational position of the rotor with respect to the stator.

  According to the embodiment, the inverter control unit repeats the application of the same voltage pulse from the inverter unit a plurality of times, and the average value of the plurality of current deviations obtained by the current deviation unit every time the voltage pulse is applied. Ask. Then, since the rotational position identifying unit identifies the rotational position of the rotor relative to the stator based on the average value of the plurality of current deviations, it is not affected by the switching of the inverter unit, so that the current is more accurately detected. Deviation can be detected.

Moreover, in the motor device of one embodiment,
The rotational position identification unit is
The relationship between the rotational position of the rotor in the stopped state and the current flowing through the coils of the respective phases of the motor unit when the same voltage pulse is applied from the inverter unit is measured in advance, and the measured rotor The rotational position of the rotor with respect to the stator is identified using a table or an expression representing the relationship between the rotational position of the current and the current flowing through the coil of each phase.

  According to the embodiment described above, the rotational position of the rotor relative to the stator is determined by the rotational position identification unit using a table or an expression representing the relationship between the rotational position of the rotor measured in advance and the current flowing through the coil of each phase. By identifying, the processing required for identifying the rotational position of the rotor can be simplified, and the identification time can be shortened.

Moreover, in the motor device of one embodiment,
The inverter part is
An upper arm switching element having one end connected to the positive electrode side of the DC power supply;
A cathode connected to the other end of the switching element for the upper arm, and an upper arm diode having an anode connected to the negative electrode side of the DC power supply;
A lower arm diode having a cathode connected to the positive electrode side of the DC power supply;
For each phase, the lower arm switching element has one end connected to the anode of the lower arm diode and the other end connected to the negative electrode side of the DC power source for each phase.
The coils of each phase of the stator were connected between the connection point of the upper arm switching element and the upper arm diode, and the connection point of the lower arm switching element and the lower arm diode.

  According to the embodiment, current can be supplied to the coils of each phase for each simple circuit block including the upper arm switching element, the upper arm diode, the lower arm switching element, and the lower arm diode.

  As is clear from the above, according to the motor device of the present invention, the initial position of the rotor can be easily estimated in the stopped state of the motor unit, and stable start-up can be performed based on the estimated initial position of the rotor. It is possible to realize a motor device that can

  Further, according to the motor device of one embodiment, when the same voltage pulse is applied from the inverter unit, the current detecting unit detects the current flowing in the coils of the respective phases of the stator of the motor unit, The deviation position determines the current deviation of the current flowing in each phase coil during application of the same voltage pulse, and the rotational position identification section calculates the current deviation of the current flowing in each phase coil determined by the current deviation section. Based on this, the rotational position of the rotor relative to the stator can be easily identified.

  Further, according to the motor device of one embodiment, immediately before and after the application of the same voltage pulse from the inverter unit, the current flowing through the coils of the respective phases of the stator is detected once by the current detection unit. Thus, the current deviation unit obtains the deviation of the two currents for each phase detected by the current detection unit as the current deviation, so that the influence of the switching noise of the inverter unit at the time of detecting the current flowing in the coil of each phase can be reduced. By reducing the current detection accuracy and improving the current detection accuracy, the estimation accuracy of the rotor position is improved.

  Further, according to the motor device of one embodiment, during the period in which the same voltage pulse is applied from the inverter unit, the switching element of the inverter unit is turned on without switching, and each phase of the stator is The current flowing through the coil is periodically detected a plurality of times, and the current deviation of the current flowing through the coil of each phase is obtained by the current deviation unit based on the plurality of currents for each phase detected by the current detection unit. Therefore, the current deviation can be detected with high accuracy because it is not affected by the switching of the inverter.

  According to the motor device of an embodiment, the inverter control unit repeats the application of the same voltage pulse from the inverter unit a plurality of times, and each time the voltage pulse is applied, a plurality of current deviation units are obtained. Since the rotational position identifying unit identifies the rotational position of the rotor relative to the stator using the average value of the current deviation, it is not affected by the switching of the inverter unit, so that the current deviation can be detected with higher accuracy. .

  Further, according to the motor device of one embodiment, the rotational position identifying unit rotates the stator relative to the stator using a table or an expression that represents the relationship between the rotational position of the rotor measured in advance and the current flowing through the coil of each phase. By identifying the rotational position of the rotor, the processing required for identifying the rotational position of the rotor can be simplified, and the identification time can be shortened.

  In addition, according to the motor device of one embodiment, current is supplied to the coils of each phase for each simple circuit block including the upper arm switching element, the upper arm diode, the lower arm switching element, and the lower arm diode. can do.

  Hereinafter, the motor device of the present invention will be described in detail with reference to the illustrated embodiments.

  FIG. 1 shows a circuit diagram of an inverter part of a motor device according to an embodiment of the present invention.

  As shown in FIG. 1, the inverter unit includes NPN transistors Qu1, Qv1, Qw1 as examples of upper-arm switching elements whose collectors are connected to the positive side of the DC power supply VDC, and the NPN transistors Qu1, Qv1, Qw1. Diodes Du1, Dv1, and Dw1 as examples of upper arm diodes having a cathode connected to the emitter and an anode connected to the negative side of the DC power source VDC, and a lower arm having a cathode connected to the positive side of the DC power source VDC As an example of a lower arm switching element in which a collector is connected to the anodes of the diodes Du2, Dv2, Dw2 as an example of the diode for use and an anode of the diodes Du2, Dv2, Dw2 and an emitter is connected to the negative side of the DC power supply VDC It has NPN transistors Qu2, Qv2, Qw2. A U-phase coil Lu is connected between the emitter of the NPN transistor Qu1 and the collector of the NPN transistor Qu2. A V-phase coil Lv is connected between the emitter of the NPN transistor Qv1 and the collector of the NPN transistor Qv2. A W-phase coil Lw is connected between the emitter of the NPN transistor Qw1 and the collector of the NPN transistor Qw2.

  Here, an NPN transistor is used for the upper arm switching element and the lower arm switching element. However, a PNP transistor may be used, or a MOSFET (Metal Oxide Semiconductor Field Effect Transistor). Other switching elements such as may be used. The inverter unit is not limited to the circuit configuration illustrated in FIG. 1, and may be an inverter unit having a circuit configuration according to the configuration of the motor unit and the driving method.

  FIG. 2 shows a configuration of a main part of the motor unit 10 driven by the inverter unit. The motor unit 10 is a gear-shaped rotor having eight salient poles 1a as shown in FIG. 1 and a stator 2 which is arranged so as to surround the rotor 1 and has 12 salient poles 2a. U-phase, V-phase, and W-phase coils (Lu, Lv, and Lw shown in FIG. 1) are wound around the salient poles 2a of the stator 2 in order clockwise.

  FIG. 3 is a control block diagram of the motor device. In FIG. 3, 20 is a three-phase AC power source, 21 is a diode bridge that converts the three-phase AC voltage from the three-phase AC power source 20 into a DC voltage, and 22 is a motor that converts the DC voltage from the diode bridge 21 to a motor. An inverter unit 23 that outputs to the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw of the unit 10 is a control device that controls the inverter unit 22. The positive side of the smoothing capacitor C is connected to the positive side output terminal of the diode bridge 21, and the negative side of the smoothing capacitor C is connected to the negative side output terminal of the diode bridge 21.

  The motor device also includes a position sensor 24 that detects the position of the rotor 1 of the motor unit 10 and a current detection that detects the current flowing from the inverter unit 22 to the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw. It has current sensors CTu, CTv, CTw as an example of the unit.

  The control device 23 includes a microcomputer, an input / output circuit, and the like. The control device 23 includes a position signal θ representing the position of the rotor 1 detected by the position sensor 24, and the U phase, V detected by the current sensors CTu, CTv, CTw. Inverter control unit 23a for controlling inverter unit 22 based on currents iu, iv, iw flowing through phase, W phase coils Lu, Lv, Lw and speed command signal ω *, U phase, V phase, W phase A current deviation part 23b for obtaining a current deviation of the current flowing through the coils Lu, Lv, Lw, and inductances of the U-phase, V-phase, W-phase coils Lu, Lv, Lw based on the current deviation obtained by the current deviation part 23b; And a rotor for the stator 2 on the basis of the magnitude relation of the inductances of the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw estimated by the inductance estimation section 23c. 1 And a rotational position identifying unit 23d for identifying a rotational position. The inverter unit 22 is controlled by the PWM control method synchronized with a predetermined carrier cycle by the inverter control unit 23a.

  FIG. 4 is a diagram illustrating voltage pulses applied to the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw, coil current, and current detection timing within the carrier period. As shown in FIG. 4, the same voltage pulse is applied to the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw. Here, the pulse width of the voltage pulse is Wt.

  FIG. 5 shows a processing flow of the control device 23 for identifying the rotational position of the rotor 1 in a stopped state of the motor device. As shown in FIG. 5, in step S1, coil currents iu (n-1), iv (n-1), U-phase, V-phase, W-phase coils Lu, Lv, Lw at predetermined timings within the carrier cycle, iw (n-1) is detected.

  In step S2, all transistors Qu1, Qv1, Qw1, Qu2, Qv2, and Qw2 are turned on for a predetermined time Wt.

  Then, after a predetermined time Wt has elapsed, all the transistors Qu1, Qv1, Qw1, Qu2, Qv2, Qw2 are turned off, and the coil currents iu (n), U, V, W phase coils Lu, Lv, Lw in step S3 iv (n) and iw (n) are detected.

Next, the process proceeds to step S4, where the current deviation unit 23b
Δiu = iu (n) -iu (n-1)
Δiv = iv (n) −iv (n−1)
Δiw = iw (n) −iw (n−1)
Is used to calculate current deviations Δiu, Δiv, Δiw of each phase.

  Next, the process proceeds to step S5, and based on the current deviations Δiu, Δiv, Δiw, the inductance estimating unit 23c estimates the magnitude relation of the inductances of the U-phase, V-phase, W-phase coils Lu, Lv, Lw.

  Then, the rotational position of the rotor 1 is identified by the rotational position identification unit 23d based on the magnitude relationship between the inductances of the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw estimated in step S5.

  Here, the identification of the rotational position of the rotor 1 uses the relationship between the rotor position and the inductance shown in FIG. For example, as shown in FIG. 6, when the U-phase salient pole of the stator 2 and the salient pole of the rotor 1 face each other, the inductance of the U-phase coil Lu is maximized, and the V-phase and W-phase coils The inductances of Lv and Lw are minimized. When the relative positional relationship between the U-phase salient poles of the stator 2 and the salient poles of the rotor 1 is shifted by 180 degrees, the inductance of the U-phase coil Lu is minimized, and the V-phase and W-phase coils Lv. , Lw has an approximately intermediate value of inductance.

  This is because as the salient pole of the stator is closer to the coil, the magnetic resistance of the coil increases and the coil current hardly flows, and the inductance of the coil changes.

  In this way, in the motor device having the above-described configuration, when a voltage pulse set with an arbitrary duty is applied to the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw as shown in FIG. 4, the voltage pulse is applied. The coil currents iu, iv and iw increase only during the interval. The coil currents iu, iv, iw at that time flow according to the coil resistance and inductance. If the coil resistances of the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw are equal, the difference in coil currents iu, iv, and iw appears as a difference in inductance. In the case of a switched reluctance motor, the inductance value changes depending on the rotor position. Therefore, the rotor position can be estimated by detecting the current of each phase and comparing the current.

  Therefore, it is possible to easily estimate the initial position of the rotor 1 in a stopped state of the switched reluctance motor, and to realize a motor device that can be stably started based on the estimated initial position of the rotor 1. .

  Further, the initial position of the rotor 1 at the time of activation is identified, and the phase to be excited first is determined in order to rotate the rotor 1 in a predetermined direction, thereby enabling stable activation.

  The duty of the voltage pulse applied to the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw needs to be set to such an extent that no torque is generated by the flowing current. In addition, by applying voltage pulses with the same duty to the U-phase, V-phase, and W-phase coils Lu, Lv, and Lw, no torque is generated in the rotor 1, so the initial position is identified without moving the rotor 1. Thus, the accuracy of determining the rotor position at the start is improved.

  Further, the timing for detecting the coil currents iu, iv, and iw is performed immediately before the voltage pulse is applied and immediately after the application of the voltage pulse is finished, as shown in FIG. The influence of noise can be reduced, and the current detection accuracy is improved, so that the estimation accuracy of the rotor position is improved.

  In addition, the measurement accuracy can be improved by executing the series of processes shown in the flowchart of FIG. 5 for each carrier period and taking the average of the current deviations Δiu, Δiv, Δiw detected repeatedly several times.

  Further, when estimating the rotor position from the detected current deviations Δiu, Δiv, Δiw, the relationship between the current deviations Δiu, Δiv, Δiw and the rotor position is measured and tabulated in advance, and this is stored in the controller 23. Thus, the rotor position can be estimated easily and quickly.

  In addition, since the inverter unit 22 is turned on without switching for a certain period (Wt) and the current deviation is periodically detected during the period, the current can be accurately detected because it is not influenced by switching.

  In the above embodiment, immediately before and after applying the voltage pulse from the inverter unit 22, the U-phase, V-phase, and W-phase coils of the stator 2 are detected by the current sensors CTu, CTv, and CTw as shown in FIG. Although the currents flowing through Lu, Lv, and Lw are sampled once, the present invention is not limited to this.

  For example, as shown in FIG. 7, during a period in which a voltage pulse is applied from the inverter unit (a period of a plurality of carrier cycles), a current i (n−3) flowing in the coils of each phase of the stator by the current detection unit. ), i (n-2), i (n-1), i (n), i (n + 1), i (n + 2), i (n + 3) multiple times at the carrier start and vertex Sampling may be performed to determine the current deviation of the current flowing in the coils of each phase based on the plurality of sampled currents for each phase.

  In the above embodiment, a motor device using a switched reluctance motor for the motor unit 10 has been described. However, the motor unit is not limited to this, and the present invention is applied to a motor device using a variable reluctance type stepping motor or the like. You may apply.

FIG. 1 is a circuit diagram of an inverter unit of a motor device according to an embodiment of the present invention. FIG. 2 is a configuration diagram of a main part of the motor unit driven by the inverter unit. FIG. 3 is a control block diagram of the motor device. FIG. 4 is a diagram showing voltage pulses applied to the U-phase, V-phase, and W-phase coils within the carrier period, coil current, and current detection timing. FIG. 5 is a flowchart showing a process flow of the control unit for identifying the rotational position of the rotor in a stopped state of the motor device. FIG. 6 is a diagram showing the relationship between the rotor position and the inductance. FIG. 7 is a diagram showing voltage pulses, coil currents, and current detection timings applied to the U-phase, V-phase, and W-phase coils when sampling is performed a plurality of times within a plurality of carrier periods.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Rotor 1a ... Salient pole 2 ... Stator 2a ... Salient pole 10 ... Motor part 20 ... Three-phase alternating current power supply 21 ... Diode bridge 22 ... Inverter part 23 ... Control device 23a ... Inverter control part 23b ... Current deviation part 23c ... Inductance estimation unit 23d ... Rotational position identification unit 24 ... Position sensor Qu1, Qv1, Qw1, Qu2, Qv2, Qw2 ... NPN transistor Du1, Dv1, Dw1, Du2, Dv2, Dw2 ... Diode Lu ... U phase coil Lv ... V phase coil Lw ... W phase coil

Claims (7)

A current is supplied to the stator (2) having a plurality of salient poles in which coils (Lu, Lv, Lw) are wound for each phase, and the coils (Lu, Lv, Lw) of the stator (2). A motor unit (10) having a rotor (1) having a plurality of salient poles rotated by a magnetic attractive force generated on the salient poles of the stator (2).
An inverter unit (22) for applying a voltage to the coils (Lu, Lv, Lw) of each phase of the stator (2) of the motor unit (10);
A current detector (CTu, CTv, CTw) for detecting current flowing from the inverter (22) to the coils (Lu, Lv, Lw) of the respective phases of the stator (2) of the motor (10); ,
The inverter unit (22) is controlled based on the current flowing through the coils (Lu, Lv, Lw) of each phase of the motor unit (10) detected by the current detection unit (CTu, CTv, CTw). At the same time, when the rotor (1) of the motor unit (10) is started from a stopped state, the coils of each phase of the stator (2) of the motor unit (10) from the inverter unit (22) ( Inverter controller (23a) for simultaneously applying the same voltage pulse to (Lu, Lv, Lw),
The coils (Lu, Lv, Lw) of the phases of the motor unit (10) detected by the current detection unit (CTu, CTv, CTw) when the same voltage pulse is applied from the inverter unit (22). A rotational position identification unit (23d) for identifying the rotational position of the rotor (1) relative to the stator (2) based on the current flowing through
Based on the rotational position of the rotor (1) relative to the stator (2) identified by the rotational position identification unit (23d), the inverter control unit (23a) rotates the rotor (1). A motor device characterized by starting the motor unit (10) by controlling the inverter unit (22) so as to output a voltage. The motor device according to claim 1,
The current deviation of the currents flowing in the coils (Lu, Lv, Lw) of the respective phases detected by the current detection units (CTu, CTv, CTw) when the same voltage pulse is applied from the inverter unit (22). A current deviation portion (23b) to be obtained;
Based on the current deviation obtained by the current deviation part (23b), the rotational position identification part (23d) identifies the rotational position of the rotor (1) relative to the stator (2). Motor device. The motor device according to claim 2,
Immediately before and immediately after the application of the same voltage pulse from the inverter unit (22), the coils (Lu, Lv, Lw) of the respective phases of the stator (2) by the current detection unit (CTu, CTv, CTw). ) Is detected once at a time,
A motor device characterized in that a deviation between two currents for each phase detected by the current detection unit (CTu, CTv, CTw) is obtained as the current deviation by the current deviation unit (23b). The motor device according to claim 2,
During the period in which the same voltage pulse is applied from the inverter unit (22), the current detection unit (CTu, CTv, CTw) causes the coils (Lu, Lv, Lw) is periodically detected multiple times,
A motor device characterized in that the current deviation is obtained by the current deviation part (23b) based on a plurality of currents for each phase detected by the current detection part (CTu, CTv, CTw). In the motor device according to any one of claims 2 to 4,
The inverter control section (23a) repeats the application of the same voltage pulse from the inverter section (22) a plurality of times, and the current deviation section (23b) is obtained every time the same voltage pulse is applied. The average value of multiple current deviations
Based on the average value of the plurality of current deviations obtained by the current deviation part (23b), the rotational position identification part (23d) determines the rotational position of the rotor (1) relative to the stator (2). A motor device characterized by identifying. In the motor device according to any one of claims 1 to 5,
The rotational position identification unit (23d)
The rotating position of the rotor (1) in the stopped state and the coils (Lu, Lv, Lw) of the respective phases of the motor unit (10) when the same voltage pulse is applied from the inverter unit (22). Using a table or formula that measures the relationship with the flowing current in advance and represents the relationship between the measured rotational position of the rotor (1) and the current flowing through the coils (Lu, Lv, Lw) of the respective phases, A motor device for identifying a rotational position of the rotor (1) relative to the stator (2). The motor device according to any one of claims 1 to 6,
The inverter part (22)
An upper arm switching element (Qu1, Qv1, Qw1) having one end connected to the positive electrode side of the DC power supply;
An upper arm diode (Du1, Dv1, Dw1) having a cathode connected to the other end of the upper arm switching element (Qu1, Qv1, Qw1) and an anode connected to the negative side of the DC power supply;
A lower arm diode (Du2, Dv2, Dw2) having a cathode connected to the positive electrode side of the DC power supply;
The lower arm switching elements (Qu2, Qv2, Qw2) having one end connected to the anode of the lower arm diode (Du2, Dv2, Dw2) and the other end connected to the negative side of the DC power supply are connected to each phase. Have
Connection point between the upper arm switching element (Qu1, Qv1, Qw1) and the upper arm diode (Du1, Dv1, Dw1), the lower arm switching element (Qu2, Qv2, Qw2) and the lower arm diode A motor device characterized in that the coils (Lu, Lv, Lw) of the stator (2) are connected between connection points of (Du2, Dv2, Dw2).

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