JP5418281B2 - Synchronous rotating machine control device and synchronous rotating machine control method - Google Patents

Description

  The present invention relates to a control device for a synchronous rotator and a control method for the synchronous rotator, and is particularly suitable for controlling the rotational operation of the rotor of the synchronous rotator using a permanent magnet as a magnetic pole of the rotor. Is.

  2. Description of the Related Art Conventionally, there is a synchronous rotating machine (electric motor or generator) provided with a rotor in which permanent magnets are arranged as magnetic poles at regular intervals in the circumferential direction. The synchronous rotating machine is operated so that the phase of the excitation current flowing through the stator (stator) winding and the rotational position of the rotor (rotor) are at a constant angle (electrical angle). For this reason, a sensor for detecting the rotational position of the rotor is provided, and a reference rotational position (hereinafter referred to as a reference position if necessary) is detected based on the output from the sensor. The inverter adjusts the phase of the excitation current flowing through the stator winding with reference to the reference position (see Patent Document 1).

JP-A-6-245314

By the way, in the synchronous rotating machine described above, in order to increase or decrease the torque, the angle between the phase of the excitation current flowing through the stator winding and the rotational position of the rotor (that is, the phase of the excitation current flowing through the stator winding) May change. In such a case, in an inverter with a low carrier frequency, the step of phase control becomes coarse, so that it is difficult to successfully connect the waveform of the excitation current flowing through the stator winding before and after the phase change. As described above, in the conventional technique, it is difficult to smoothly control the phase, and the state where the synchronization speed and the actual rotation speed do not coincide (step out) is likely to occur, and there is a possibility that the synchronization state cannot be restored. There was a point. This becomes conspicuous when a multipolar rotor is rotated at high speed. Therefore, it is conceivable to employ an inverter having a high carrier frequency, but such an inverter has a large amount of heat generation and is expensive.
Further, since the rotor is stopped when the synchronous motor is started, the rotational position of the rotor cannot be detected by the above-described sensor. Therefore, there has been a problem that it is not easy to determine the phase of the excitation current flowing through the stator winding at the time of starting.

The present invention has been made in view of the above problems, and it is possible to easily and accurately determine the phase of the excitation current flowing in the stator winding in the synchronous rotating machine including the rotor using the permanent magnet. The purpose is to be able to.

A control apparatus for a synchronous rotating machine according to the present invention is a control apparatus for a synchronous rotating machine that controls a rotating operation of a rotor of a synchronous rotating machine that uses a permanent magnet as a magnetic pole of the rotor, and is a generation unit different from the rotor A generating unit that generates rotational position information indicating a rotational position of a rotor of the synchronous rotating machine , at least a part of which is attached to the rotating shaft of the synchronous rotating machine and rotates together with the rotating shaft; A detection unit that can rotate coaxially with a rotor of the synchronous rotating machine, and that detects a reference position of the rotor based on a detection position of rotation position information generated by the generation unit; An excitation current having a fixed phase based on the reference position is generated as a drive unit that rotates the detection unit by a motor coaxially with the rotor of the synchronous rotator and an excitation current that flows through the stator winding of the synchronous rotator. and an inverter, Before starting the synchronous rotating machine, based on the rotational position information generated by the generating unit by rotating the detecting unit by the driving unit, the excitation current flowing through the stator winding of the synchronous rotating machine When determining the initial phase and instructing the excitation current to flow at the determined initial phase, and changing the phase of the excitation current flowing through the stator winding of the synchronous rotating machine, the stator of the synchronous rotating machine And a control unit that instructs to rotate the detection unit by an angle corresponding to a change in the phase of the excitation current flowing through the winding .

A method for controlling a synchronous rotating machine according to the present invention is a method for controlling a synchronous rotating machine that uses a permanent magnet as a magnetic pole of a rotor to control a rotating operation of the synchronous rotating machine, and is a generation unit different from the rotor. A first generation step of generating rotational position information indicating a rotational position of a rotor of the synchronous rotating machine by a generating unit that is attached to the rotating shaft of the synchronous rotating machine and rotates together with the rotating shaft; The detection unit capable of rotating coaxially with the rotor of the synchronous rotating machine detects the reference position of the rotor based on the detection position of the rotation position information generated in the first generation step. A detection step, a driving step in which the detection unit is rotated by a motor coaxially with a rotor of the synchronous rotating machine, and an excitation current flowing in a stator winding of the synchronous rotating machine with a fixed phase based on the reference position Excitation current A second generation step of generating by an inverter, before starting the synchronous rotary machine, based on the rotational position information generated by the generating unit by rotating the detector by the driving step, the synchronous rotation Determine the initial phase of the excitation current flowing through the stator winding of the machine, instruct the flow of the excitation current at the determined initial phase, and change the phase of the excitation current flowing through the stator winding of the synchronous rotating machine In this case, the method includes a control step of instructing to rotate the detection unit by an angle corresponding to a change in the phase of the excitation current flowing through the stator winding of the synchronous rotating machine .

According to the present invention, it is possible to easily and accurately determine the phase of the exciting current flowing in the stator winding in a synchronous rotating machine having a rotor with permanent magnets.

It is a figure which shows embodiment of this invention and shows an example of a structure of the control system of a synchronous motor. 1 is a cross-sectional view illustrating an example of a schematic configuration of a synchronous motor, a rotational position detection sensor, and a sensor driving unit according to an embodiment of the present invention. It is a figure which shows embodiment of this invention and shows an example of a structure of a rotation position detection sensor. It is a figure which shows embodiment of this invention and shows an example of a mode that the position of a phototransistor group is changed. It is a figure which shows embodiment of this invention and shows the 1st modification of a rotation position detection sensor. It is a figure which shows embodiment of this invention and shows the 2nd modification of a rotation position detection sensor.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating an example of the configuration of a synchronous motor control system. In each drawing, only the configuration necessary for the description is simplified.
In FIG. 1, the synchronous motor control system includes a synchronous motor 100, a rotational position detection sensor 200, a sensor driving unit 300, a control unit 400, and an inverter 500.
The synchronous motor 100 is an example of a synchronous rotating machine, and includes a rotor (rotor), a stator (stator), a rotating shaft, and the like, and drives a load 600. The synchronous motor 100 includes a plurality of permanent magnets as magnetic poles of the rotor, and the plurality of permanent magnets are arranged at regular intervals in the circumferential direction.

The rotational position detection sensor 200 is a sensor for detecting the current position (magnetic pole position) of the rotor of the synchronous motor 100 and the reference position. The rotational position detection sensor 200 includes a generation unit 201 and a detection unit 202 (see FIGS. 2 and 3). Although details will be described later, the generation unit 201 is attached at least partially to the rotation shaft of the synchronous motor 100 and generates rotation position information indicating the rotation position of the rotor. On the other hand, the detection unit 202 is attached to a case that can rotate (rotate) coaxially with the rotation shaft of the synchronous motor 100, and based on the rotation position information generated by the generation unit, the rotation position ( (Including the reference position). In particular, the reference position of the rotor is detected based on the detection position of the rotational position information generated by the generation unit 201.
The sensor driving unit 300 is for rotating (rotating) a case 303 (see FIG. 2), to which the detection unit 202 of the rotational position detection sensor 200 is attached, coaxially with the rotation shaft of the synchronous motor 100. .

  The control unit 400 is realized by, for example, a computer having a CPU, a ROM, a RAM, an HDD, and various interfaces, and controls the operations of the sensor driving unit 300 and the inverter 500. Although details will be described later, in the present embodiment, the controller 400 generates a drive signal for the sensor driver 300 before starting the synchronous motor 100. Based on the rotational position information detected by the rotational position detection sensor 200 by rotating the case 303 to which the detection unit 202 of the rotational position detection sensor 200 is attached in this manner, the control unit 400 performs the control of the synchronous motor 100. Determine the initial phase of the excitation current flowing through the stator winding. Then, the control unit 400 instructs the inverter 500 to flow an excitation current at the initial phase.

  In addition, when changing the phase of the excitation current flowing through the stator winding of the synchronous motor 100, the control unit 400 does not instruct the inverter 500 to change the phase, but the angle corresponding to the changed phase. Only the case 303 to which the detection unit 202 of the rotational position detection sensor 200 is attached is instructed to rotate. For example, the control unit 400 has a table in which the relationship between the phase of the excitation current and the rotation angle of the case 303 is stored in advance so that the phase advance / delay and the rotation direction can be identified. Using this, the rotation angle of the case 303 can be determined. Thus, by making it possible to identify the phase advance / delay and the rotation direction, the rotation direction can be determined depending on whether the phase is advance or not, and the amount of rotation can be reduced. Here, the phase of the excitation current is proportional to the rotation angle of the case 303.

Instead of using a table, an expression representing the relationship between the phase of the excitation current and the rotation angle of the case 303 may be used. In addition, when the phase change indication value is not the change value from the initial phase but the change value from the current phase, each time the phase is changed, it corresponds to the phase after the change or the phase. What is necessary is just to memorize | store the rotation angle of case 303 to perform.
The inverter 500 generates an excitation current that flows through the stator winding of the synchronous motor 100 based on an instruction from the control unit 400. At this time, the inverter 500 generates a waveform of the excitation current in synchronization with the rotational position information detected by the rotational position detection sensor 200. The supply of excitation current by the inverter 500 is realized by vector control, phase control, or the like. Since these can be realized by a known technique, the details are omitted here.

FIG. 2 is a cross-sectional view illustrating an example of a schematic configuration of the synchronous motor 100, the rotational position detection sensor 200, and the sensor driving unit 300. Specifically, FIG. 2 is a cross-sectional view taken from a direction perpendicular to the rotation axis of the synchronous motor 100.
As described above, the synchronous motor 100 includes the rotor 101, the stator 102, and the rotation shaft 103, and is housed in the housing (frame) 104. The stator 102 is fixed to the housing 104 by a fixing ring (not shown).
A case 105 that accommodates the rotational position detection sensor 200 and the sensor driving unit 300 is attached (fixed) to the housing 104. The case 105 does not move even when the synchronous motor 100 is driven.

The sensor driving unit 300 includes a motor 301, a gear 302, and a case 303.
The motor 301 is attached to the case 105 and rotates the case 303 coaxially with the rotation shaft 103 of the synchronous motor 100 based on an instruction from the control unit 400. The motor 301 is realized by, for example, a servo motor or a stepping motor. The motor 301 can rotate the case 303 in both the clockwise and counterclockwise directions.
The gear 302 is disposed between the motor 301 and the case 303 and defines a minimum unit of rotation of the case 303 by the motor 301.
The case 303 accommodates the rotational position detection sensor 200 and the tip of the rotating shaft 103 of the synchronous motor 100 and rotates coaxially with the rotating shaft 103 of the synchronous motor 100.

The rotational position detection sensor 200 includes a generation unit 201 and a detection unit 202.
As described above, the generation unit 201 is attached (fixed) to at least a tip portion of the rotation shaft 103 of the synchronous motor 100 and generates rotation position information indicating the rotation position of the rotor 101. The detection unit 202 is attached (fixed) to the case 303, detects the rotation position (including the reference position) of the rotor 101 based on the rotation position information generated by the generation unit 201, and outputs the signal to the control unit. 400.

FIG. 3 is a diagram illustrating an example of the configuration of the rotational position detection sensor 200. In the present embodiment, the rotational position detection sensor 200 is configured using an optical rotary encoder.
The rotational position detection sensor 200 includes a “slit disk 201a, an LED (Light Emitting Diode) 201b, and a mask 201c” that is an example of the generation unit 201, and a “phototransistor group” that is an example of the detection unit 202. ing.
The slit disk 201 a is attached to the rotation shaft 103 and rotates together with the rotation shaft 103. A plurality of slits 211 arranged at equal intervals in the circumferential direction are formed in a relatively outer peripheral region of the slit disk 201a. Further, one slit 212 is formed in a relatively inner peripheral region of the slit disk 201a.

The LED 201b is for emitting light substantially perpendicular to the surface direction of the slit disk 201a.
The mask 201c is for transmitting part of the light emitted from the LED 201b in the direction of the slit disk 201a.
The area on the relatively upper side (the side far from the rotation shaft 103) of the mask 201c is the same as the interval between the two slits 211 formed adjacent to each other in the area on the relatively outer peripheral side of the slit disk 201a. Two slits 221 and 222 having a distance of are formed. These two slits 221 and 222 and the two slits 211 formed adjacent to each other in the relatively outer peripheral region of the slit disk 201a may face each other in the direction along the rotation axis 103. A slit disk 201a and a mask 201c are arranged so that they can be made.
Further, it is a region on the lower side of the mask 201c (side closer to the rotating shaft 103), and in a direction along the slit 212 and the rotating shaft 103 formed on the inner peripheral side of the slit disk 201a. One slit 223 is formed in a region where the two can face each other.

  The phototransistor group 202 includes three phototransistors 231 to 233 that receive light transmitted through the slit disk 201a. Specifically, two phototransistors 231 and 232 are arranged in a relatively upper region (a side far from the rotation shaft 103). More specifically, these two phototransistors 231 and 232 are respectively in the direction along the two slits 211 and the rotation axis 103 formed adjacent to each other in the relatively outer peripheral region of the slit disk 201a. It is arranged in a region where it can face up. On the other hand, one phototransistor 233 is disposed in a relatively lower region (side closer to the rotation shaft 103). More specifically, the phototransistor 233 is disposed in a region where the phototransistor 233 can face the slit 212 formed on the relatively inner peripheral side of the slit disk 201 a in the direction along the rotation shaft 103.

  By configuring the rotational position detection sensor 200 as described above, light transmitted through the slit disk 201a is output as rotational position information, and this light is input to the phototransistors 231 to 233, whereby the rotor 101 is output. Is detected. The current position of the rotor 101 is detected by the phototransistors 231 and 232 receiving light that passes through the slit 211 of the slit disk 201a. Further, when the phototransistor 233 receives the light transmitted through the slit 212, the reference position of the rotor 101 is detected. Since the rotary encoder itself can be realized by a known technique, the details of its operation are omitted here.

As described above, the LED 201b, the mask 201c, and the phototransistor group 202 are attached to the case 303. Therefore, when the case 303 rotates coaxially with the rotation shaft 103 of the synchronous motor 100, the LED 201b, the mask 201c, and the phototransistor group 202 are not changed in their relative positional relationship, but in the circumferential direction of the slit disk 201a. Rotate along.
FIG. 4 is a diagram illustrating an example of how the position of the phototransistor group 202 is changed. When the position of the phototransistor group 202 is changed from the position shown in FIG. 4A to the position shown in FIG. 4B (in FIG. 4, it is assumed that the rotation angle is θ and the rotation direction is clockwise). The position at which the phototransistor group 202 receives light transmitted through the slit 212 of the slit disk 201a is also changed. As described above, in FIGS. 4A and 4B, the phototransistors 231 to 233 are opposed to the slits 221 to 223 along the direction of the rotating shaft 103 (for example, The slit 221 is present in the direction perpendicular to the paper surface with respect to the phototransistor 231).

Therefore, if the case 303 is rotated according to the change in the phase of the excitation current flowing through the stator winding of the synchronous motor 100, the reference position of the excitation current phase changes. Therefore, the inverter 500 can synchronize with the reference position in synchronism with the detection of the signal by the rotational position detection sensor 200 without performing an operation for changing the waveform of the excitation current corresponding to the phase change by the electronic circuit. It is possible to change the phase of the excitation current simply by generating a waveform of the excitation current having a fixed phase with respect to.
Further, by rotating the case 303 before starting the synchronous motor 100, the relative positional relationship between the slit disk 201a, the LED 201b, the mask 201c, and the phototransistor group 202 can be changed. Therefore, the stop position of the rotor 101 of the synchronous motor 100 can be detected without driving the synchronous motor 100, and the phase of the excitation current flowing through the stator winding of the synchronous motor 100 according to the rotational position. Therefore, the synchronous motor 100 can be easily started.

As described above, in the present embodiment, the rotational position detection sensor 200 is configured by an optical rotary encoder. Specifically, a slit disk 201 that is one of the generation units 201 is attached to the rotation shaft 103 of the synchronous motor 100. In addition, the LED 201 b and the mask 201 c that are other parts of the generation unit 201 and the phototransistors 231 to 233 that are the detection unit 202 are attached to a case 303 that rotates coaxially with the rotation shaft 103. Then, when changing the phase of the exciting current flowing through the stator winding, or when determining the initial phase of the exciting current, the control unit 400 rotates the case 303. Therefore, since the position of the phototransistor 233 that inputs information on the reference position of the excitation current phase can be changed, the phase of the excitation current can be changed smoothly without calculation by an electronic circuit. Further, the driving initial phase of the excitation current can be determined without driving the synchronous motor 100. Therefore, the phase of the excitation current flowing through the stator winding in the synchronous motor 100 including the rotor 101 using the permanent magnet can be easily and accurately determined without using an expensive high-performance inverter. . This is particularly effective when a multipolar rotor is rotated at a high speed (when the frequency of the excitation current flowing through the stator winding is high). Further, the case 303 only needs to be rotated by an angle corresponding to one pole of the rotor 101 (if the number of poles is two, the angle corresponding to one pole is 180 ° (= 360 ° / 2)). . Therefore, the case 303 can be rotated without using a special part such as a slip ring.

In the present embodiment, the case where the LED 201b, the mask 201c, and the phototransistor group 202 are attached to the same case 303 has been described as an example. However, the detection unit 202 is rotated coaxially with the rotation shaft 103 without changing the relative positional relationship between the generation unit 201 (slit disk 201a, LED 201b, mask 201c) and the detection unit 202 (phototransistor group 202). If it is made to do, it is not necessarily necessary to do this. For example, the LED 201b and the mask 201c, and the phototransistor group 202 may be attached to different cases.
Further, in the present embodiment, for example, by using the rotational position detection sensor 200, the sensor driving unit 300, the control unit 400, and the inverter 500, the rotation of the rotor of the synchronous rotating machine using the permanent magnet as the magnetic pole of the rotor. An example of a control device for a synchronous rotating machine that controls the operation is realized.

In the present embodiment, the rotational position detection sensor 200 is configured by an optical rotary encoder. However, for example, the following can be used instead of the optical encoder.
(Modification 1)
FIG. 5 is a diagram illustrating a first modification of the rotational position detection sensor. In this modification, a rotational position detection sensor is configured using a magnetic rotary encoder.
As shown in FIG. 5, the rotational position detection sensor 700 includes a multipolar permanent magnet 701 and a sensor unit 702.
The permanent magnet 701 is attached to the rotating shaft 103 of the synchronous motor 100 and rotates together with the rotating shaft 103. The sensor unit 702 includes a Hall sensor IC (Integrated Circuit), inputs a change in magnetic flux from the permanent magnet 701 as rotational position information, converts it into an electrical signal, and transmits it to the control unit 400 .
As described above, when the rotational position detection sensor is a magnetic rotary encoder, the generation unit 201 is configured by at least the permanent magnet 701 and the detection unit is configured by the sensor unit 702.

(Modification 2)
FIG. 6 is a diagram illustrating a second modification of the rotational position detection sensor. In this modification, a rotational position detection sensor is configured using a resolver.
As shown in FIG. 6, the rotational position detection sensor 800 includes a rotor 801 and a stator 802.
The rotor 801 is attached to the rotation shaft 103 of the synchronous motor 100 and rotates together with the rotation shaft 103. When AC power is applied as rotational position information to the excitation coil provided in the rotor 801, a voltage is generated in the detection coil provided in the stator 802, and this voltage information is transmitted to the control unit 400.
As described above, when the rotational position detection sensor is a resolver, at least the rotor 801 forms a generation unit, and the stator 802 forms a detection unit.
As described above, since various types of rotational position detection sensors can be used, the rotational position detection sensor is not limited to the one described above. Moreover, you may apply not to a synchronous motor but to a synchronous generator.

  It should be noted that the embodiments of the present invention described above are merely examples of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. Is. That is, the present invention can be implemented in various forms without departing from the technical idea or the main features thereof.

DESCRIPTION OF SYMBOLS 100 Synchronous motor 200, 700, 800 Rotation position detection sensor 201,701,801 Generation part 202,702,802 Detection part 300 Sensor drive part 301 Motor 302 Gear 303 Case 400 Control part 500 Inverter 600 Load

Claims (4)

A control device for a synchronous rotating machine that controls a rotating operation of a rotor of a synchronous rotating machine using a permanent magnet as a magnetic pole of the rotor,
A rotational position indicating a rotational position of the rotor of the synchronous rotator, the generator being different from the rotor, wherein at least a part is attached to the rotational shaft of the synchronous rotator and rotates together with the rotational shaft. A generator for generating information;
A detection unit capable of rotating coaxially with a rotor of the synchronous rotating machine, and detecting a reference position of the rotor based on a detection position of rotation position information generated by the generation unit;
A drive unit that is coaxial with the rotor of the synchronous rotating machine and that rotates the detection unit by a motor ;
As an excitation current flowing through the stator winding of the synchronous rotating machine, an inverter that generates an excitation current having a fixed phase based on the reference position;
Before starting the synchronous rotating machine, the excitation current flowing in the stator winding of the synchronous rotating machine based on the rotational position information generated by the generating unit by rotating the detecting unit by the driving unit. When determining the initial phase and instructing the excitation current to flow at the determined initial phase, and changing the phase of the excitation current flowing through the stator winding of the synchronous rotating machine, the stator of the synchronous rotating machine A control device for a synchronous rotating machine , comprising: a control unit that instructs to rotate the detection unit by an angle corresponding to a change in a phase of an exciting current flowing through a winding . The detection unit is attached to a case capable of rotating coaxially with a rotor of the synchronous rotating machine,
The control device for a synchronous rotating machine according to claim 1, wherein the driving unit rotates the case coaxially with a rotor of the synchronous rotating machine. A control method for a synchronous rotating machine for controlling the rotational operation of a synchronous rotating machine using a permanent magnet as a magnetic pole of a rotor,
Rotation position indicating a rotational position of the rotor of the synchronous rotating machine by a generating unit that is different from the rotor and at least a part of which is attached to the rotating shaft of the synchronous rotating machine and rotates together with the rotating shaft. A first generating step for generating information;
Detection that detects the reference position of the rotor based on the detection position of the rotational position information generated in the first generation step by a detection unit that can rotate coaxially with the rotor of the synchronous rotating machine Process,
A driving step of rotating the detection unit by a motor coaxially with a rotor of the synchronous rotating machine;
A second generation step of generating, by an inverter, an excitation current having a fixed phase based on the reference position as an excitation current flowing through the stator winding of the synchronous rotating machine;
Before starting the synchronous rotating machine, based on the rotational position information generated by the generating unit by rotating the detecting unit by the driving process, the excitation current flowing in the stator winding of the synchronous rotating machine When determining the initial phase and instructing the excitation current to flow at the determined initial phase, and changing the phase of the excitation current flowing through the stator winding of the synchronous rotating machine, the stator of the synchronous rotating machine And a control step for instructing the detector to rotate by an angle corresponding to a change in the phase of the excitation current flowing through the winding . The detection unit is attached to a case capable of rotating coaxially with a rotor of the synchronous rotating machine,
The method for controlling a synchronous rotating machine according to claim 3 , wherein in the driving step, the case is rotated coaxially with a rotor of the synchronous rotating machine.

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