JP2000152565A - Device for detecting rotor's position of dynamo-electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply perform the accurate positional detection of a rotor, by constituting the device such that it has an arithmetic logic unit which takes the logical sum of the output signals of two sensors. SOLUTION: In the case of a rotor position detector suitable for a turbine generator, recesses 1a and projections 1b are made alternately all around a rotor 1, and a two-piece set of sensors 2 composed of a sensor 2a for ON and a sensor 2b for OFF are arranged in the vicinity of the periphery. Then, the angle between the line which the connects center of the rotor 1 with the sensor 2a and the line which connects the center of the rotor 1 and the sensor 2b is equal to an electric angle which shows the phase difference of the current flowing in wincing so that they can perform high detection of rotor's position, and the sensor 2a and the sensor 2b are connected to an arithmetic logic unit 3 through a signal cable. Hereby, the accurate grasp of the absolute positional relation between the rotor and the sensor becomes needless, and the highly accurate positional detection can be performed simply without processing the rotor precisely.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor position detecting device for a rotating electric machine, and more particularly to a rotor position detecting device suitable for a thyristor-starting rotating electric machine.

[0002]

2. Description of the Related Art A conventional rotor phase detecting device is, for example, as disclosed in Japanese Patent Application Laid-Open No. Hei 10-23714, in which a set of sensors is provided near the outer periphery of a rotating body having irregularities formed on the outer periphery. Was to be arranged.

[0003]

However, in the above-described conventional rotor phase detecting device, when the rotor position is to be detected with high accuracy, the accurate absolute positional relationship between the rotating body and the sensor must be grasped. Therefore, it is necessary to precisely process the irregularities on the outer periphery of the rotating body.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rotor position detecting device of a rotating electric machine which can easily detect a high-precision rotor position without precisely processing a rotating body.

[0005]

According to the present invention, there is provided a rotor position detecting device for a rotating electric machine, wherein a rotating body provided on a shaft of a rotor and having irregularities alternately formed on an outer peripheral portion thereof is provided.
It has a pair of two sensors arranged near the outer periphery of the rotating body and operating according to the unevenness of the rotating body, and a logical operation device for calculating the logical sum of the output signals of the two sensors.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a rotor phase detecting device according to the present embodiment. The rotor phase detection device according to the present embodiment is a rotor phase detection device suitable for a rotating electric machine for starting a thyristor, for example, a turbine generator. 1 in the drawing
Is a rotating body provided on the rotating shaft of the rotor of the rotating electric machine. Concave portions 1a and convex portions 1b are alternately formed on the outer periphery of the rotating body 1 over the entire periphery.

In the vicinity of the outer peripheral portion of the rotating body 1, a pair of two sensors 2 composed of an ON sensor 2a and an OFF sensor 2b are arranged. The interval between the sensor 2a and the sensor 2b, that is, the angle of the line connecting the center of the rotating body 1 and the sensor 2a and the angle of the line connecting the center of the rotating body 1 and the sensor 2b is determined by the rotor position detection with high accuracy. In this case, the electric angle is equal to the electric angle indicating the phase difference of the current flowing through the winding. Although only one set of sensors is shown in the drawing, actually, since the turbine generator is a three-phase AC machine, three sets of sensors are arranged at 120-degree intervals corresponding to each phase.

For the sensors 2a and 2b, for example, optical sensors having a light emitting function and a light receiving function are used, and light is emitted toward the concave and convex portions of the rotating body 1 and reflected from the concave and convex portions of the rotating body 1, respectively. Receives light. Then, it operates according to the intensity of the received light. That is, the sensor 2a and the sensor 2b
Operates according to the distance to the rotating body 1. In the present embodiment, a setting is made such that a pulse signal is output when the convex portion 1b of the rotating body 1 is detected, and the pulse signal is stopped when the concave portion 1a of the rotating body 1 is detected.

The sensors 2a and 2b are connected to the logical operation device 3 via a signal cable. The logical operation device 3 performs an OR operation on the pulse signal output from the sensor 2a and the pulse signal output from the sensor 2b.
It has an R circuit.

The logical operation device 3 is connected to a thyristor starting device (not shown) via a signal cable. The pulse signal output from the logical operation device 3 is input to the thyristor starting device. The thyristor starting device operates based on the pulse signal output from the logical operation device 3.

FIGS. 2A and 2B show the output pulse signal waveforms of the sensors 2a and 2b and the pulse signal waveforms resulting from their logical operations, respectively. FIG. 2A shows the output pulse signal waveform of the sensor 2a, and FIG. 2c shows an output pulse signal waveform of the sensor 2a, and FIG.
(D) is a pulse signal waveform obtained as a result of calculating the logical product of the output pulse signal of the sensor 2a and the output pulse signal of the sensor 2b. .

As described above, in this embodiment, a pulse signal is output when the convex portion 1b of the rotating body 1 is detected, so that the pulse signal “1” indicates the detection of the convex portion 1b, Since the operation is stopped when the concave portion 1a is detected, the pulse signal "0" indicates the detection of the concave portion 1a.

As is apparent from the drawing, the pulse signal obtained as a result of the logical sum of the output pulse signal of the sensor 2a and the output pulse signal of the sensor 2b is converted to the ON sensor 2a.
Rises when the convex portion 1b is detected, and goes down when the concave portion 1a is detected by the OFF sensor 2b. Therefore,
When the pulse signal is output from the logical operation device 3, the relative positional relationship between the rotating body 1 and the sensor 2 is always constant,
The thyristor starting device operates only by the pulse signal output from the logical operation device 3.

On the other hand, the pulse signal obtained as a result of the logical product of the output pulse signal of the sensor 2a and the output pulse signal of the sensor 2b indicates that the ON sensor 2a and the OFF sensor 2b have detected the convex portion 1b. It rises in this case and falls when either the ON sensor 2a or the OFF sensor 2b detects the recess 1a. Therefore, the logical operation device 3
1 and sensor 2 when a pulse signal is output from
The relative positional relationship always changes, and in order to operate the thyristor starting device, in addition to the pulse signal output from the logical operation device 3, it is necessary to determine whether the AC current flowing through the stator winding is positive or negative. The detected voltage value of the stator winding is required.

According to the present embodiment described above, a pair of two sensors 2 are arranged near the outer periphery of the rotating body 1 having the uneven portion, so that two sensors are used for detecting the rotor position. It is only necessary to evaluate the time difference between the pulse signals output from the rotator, and it is no longer necessary to accurately grasp the absolute positional relationship between the rotator and the sensor, which was conventionally required for accurate rotor position detection. Precise processing of irregularities can be unnecessary.

Further, according to the present embodiment, the logical sum of the pulse signals output from the two sensors is calculated, so that the rotating body 1 when the pulse signal is output from the logical operation device 3 and The relative positional relationship of the sensor 2 is always constant, and the thyristor can be controlled only by the pulse signal output from the logical operation device 3.

[0018]

As described above, according to the rotor position detecting device for a rotating electric machine according to the present invention, a rotating body provided on a shaft of the rotor and having irregularities alternately formed on an outer peripheral portion is disposed near an outer periphery of the rotating body. And a logical operation device for calculating the logical sum of the output signals of the two sensors, which has been conventionally required for accurate rotor position detection. It is not necessary to accurately grasp the absolute positional relationship between the rotating body and the sensor, and precise processing of the unevenness of the rotating body is unnecessary. Further, the thyristor can be controlled only by the pulse signal output from the logical operation device. Therefore, it is possible to provide a rotor position detecting device of a rotating electric machine that can easily perform high-accuracy position detection without precisely processing a rotating body.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a rotor position detecting device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a pulse signal waveform output from the sensor and the logical operation device of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rotating body, 2 ... Sensor, 3 ... Logical operation device.

Continued on the front page (72) Inventor Osamu Nakura 3-1-1, Sachimachi, Hitachi-shi, Ibaraki Pref. Hitachi, Ltd. Hitachi Plant (72) Inventor Hiroshi Morimoto 3-1-1, Sachimachi, Hitachi-shi, Ibaraki F-term in Hitachi Plant, Hitachi Ltd. (reference) 5H611 AA01 BB02 BB04 PP07 QQ03 RR06 TT01 UA01 UB00

Claims (1)

[Claims] 1. A rotor position detecting device for a rotary electric machine for detecting a position of a rotor, comprising: a rotor provided on a shaft of the rotor and having irregularities alternately formed on an outer peripheral portion; A pair of two sensors arranged in the same manner and operating in accordance with the irregularities, and a logical operation device for calculating a logical sum of output signals of the two sensors. .