JPH0564557B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a determination device for determining whether a position detector for detecting the rotor position of a commutatorless motor is normal or abnormal.

[Prior art and its problems]

FIG. 4 is a block diagram showing a conventional example of a non-commutator motor control device. In the figure, 11 is a power supply side converter, 12 is an inverter, and 1
3 is a DC reactor. 14 is inverter 1
It is an electric motor (motor) driven via 2,
15 is a position detector, and 16 is a pulse generator for speed control. 19 is speed regulator (ASR)
Then, the speed of the motor 14 is adjusted according to the speed command value N ^* . Reference numeral 18 denotes a current regulator that controls the DC intermediate current Id of the main circuit in accordance with the output of the speed regulator 19. Reference numeral 17 denotes a firing angle regulator that controls the phase of converter 11 according to the output of current regulator 18. 20 is a pulse distributor that outputs an ignition pulse to the inverter 12 based on the signal from the position detector 15. This pulse distributor 20 includes:
A lead angle command value calculated by a lead angle calculator 21 from the motor terminal voltage, motor current, etc. is input, and the inverter 12 phase is controlled. In this case, the signal from the position detector 15 is used as a reference signal to determine the current flow arm and phase of the inverter 12, and if this position detector becomes abnormal, commutation failure and resulting overcurrent may occur. will occur. In other words, for the commutatorless motor 14,
The position detector 15 plays the role of a brush of a DC machine, and can be said to be a sensor that plays a very important role in determining the flow arm of the inverter 12 and controlling its phase. However, in the past, the abnormality of the position sensor was not detected, and the resulting commutation failure or overcurrent was treated as a failure and the equipment was protected, and the cause of the failure was also investigated. In terms of maintenance, countermeasures were also insufficient, as an abnormality in the position detector was only discovered during the process of investigating the causes of the current failure (current failure, overcurrent).

[Purpose of the invention]

The present invention was made under the above circumstances, and an object thereof is to make it possible to check the operation of a position detector easily and inexpensively, to ensure protection of a power conversion device, and to facilitate its maintenance. shall be.

[Means to achieve the purpose]

In order to achieve the above object, the present invention provides an abnormality determination device for a position detector, which includes two systems of position detectors and determination means for inputting both signals and determining an output abnormality of one of the systems, comprising: detecting a position to be determined; The detector is used to control polyphase non-commutator motors and outputs in a logical pattern for polyphase switching.The other position detector consists of a pulse generator and a counter that also serve as speed detection. The output is counted by a counter to output the absolute position, and the determination means consists of a memory in which the normal position detector output pattern corresponding to the counter output is stored and a logic comparison section, A logical comparison section compares the normal output pattern from the memory based on the absolute position output of the position detector with the output pattern from the position detector to be determined to determine an abnormality and the abnormal detector. Provided is a device for determining abnormality in a device.

[Effect]

In the position detector abnormality determination device described above, the position detector on the side to be determined is used to control a multi-phase commutatorless motor and outputs a logic pattern for multi-phase switching. The other position detector is composed of a pulse generator and a counter that also serves as speed detection, and counts the output of the generator with the counter to output an absolute position.

The determination means includes a memory in which a normal position detector output pattern corresponding to the counter output is stored, and a logic comparison section, and is configured to compare the normal output pattern from the memory and the normal position detector output pattern based on the absolute position output from the pulse generator. The logic comparison section compares the output pattern from the determination position detector to determine an abnormality and identify the abnormality detector.

[Embodiments of the invention]

Fig. 1 is a configuration diagram showing an embodiment of this invention;
The figure is a time chart showing the relationship between the position detector output and the counter output, and FIG. 3 is a configuration diagram showing an example of the memory configuration. In FIG. 1, 1 is an arithmetic and control device such as a microcomputer, 2 is a counter,
3 is a waveform shaping circuit, 4 and 5 are latch circuits, and 6 is a memory.

A counter 2 counts pulses from a speed control pulse generator (PG), and its output is latched by a latch circuit 4. The waveform shaping circuit 3 shapes the output signal from the position detector into a predetermined waveform, and the latch circuit 5 latches the waveform-shaped position detection signal. Incidentally, the position detection signal at this time is shown as in FIG. 2A. Arithmetic control device 1
outputs a latch signal to the latch circuits 4 and 5 at the time of checking the state of the position detector, thereby latching the contents of the counter 2 and the state of the position detector signal, respectively. The output of counter 2 is
It is reset by a reset signal from the waveform shaping circuit 3 so as to correspond to the absolute position of the rotor.
Incidentally, the output waveform of the counter 2 is shown as in FIG. 2B. The pattern of the position detector signal in a normal case corresponding to the absolute position of the rotor is written in advance in the memory 6, and the arithmetic and control unit 1 uses the contents of the counter 2 latched by the latch circuit 4 as an address. , reads the pattern from memory 6. At this time, if the contents of the counter 2, that is, the position of the rotor, are reset every 360°el in electrical angle, the address for the memory 6 will be 360°el as shown in FIG. divided into 6
Six of A ₁ , A ₂ , A ₃ , A ₄ , A ₅ , and A ₆ are sufficient,
Correct patterns are stored in advance for these six addresses as shown in FIG. The pattern read from the memory 6 is compared with the position detector signal latched by the latch circuit 5, and if they do not match, it is considered abnormal. At this time, if a comparison is made using an exclusive OR circuit, not only a mismatch can be detected, but also an abnormal position detector can be detected. For example, if the contents of the counter read by the latch circuit 4 are in the interval _A1 , the pattern "101" is read from the memory 6 as a normal value using _A1 as the address. If the position detector signal pattern from the latch circuit 5 at that time is, for example, "001", then
By calculating the exclusive OR of these two patterns, "100" is obtained as an output, and it can be determined that the U-phase position detector set to "1" is abnormal.

In this embodiment, the case where the position detector has three phases has been explained, but it goes without saying that it is simple and expandable even in the case of six phases. In addition, if there is a possibility of false detection due to the timing of reading, such as when the pattern of the position detector changes, abnormality detection should not be performed before or after the pattern change, that is, near the specific value of counter 2. It is necessary to take the following method. Also, in this example,
Counter 2 is designed to be reset by a position detector signal in order to detect the absolute position of the rotor, but this reset is performed only with the first reset signal after the power is turned on, and thereafter. By using a counter that can be automatically reset using an overflow or underflow of the count value (for example, 360°el corresponds to 256 bits and is counted by an 8-bit counter), the value of this counter can be changed. It can be used as a highly reliable reference value, and therefore it is possible to detect abnormalities in the position detector with high precision. In addition,
If you only need to detect an abnormality in the position sensor,
The latch circuit 4 that latches the output of the counter 2 is not necessary; the pattern read from the latch circuit 5 is simply compared with the pattern in the memory 6, and if it differs from the pattern registered in the memory, it is determined that there is an abnormality. Just do it.

〔Effect of the invention〕

According to this invention, an abnormality in the position detector can be determined by comparing the output signal of the position detector with the original pattern of the position detector signal obtained from the counter output indicating the absolute position of the rotor. Therefore, not only can the power conversion device be quickly protected, but also its maintenance can be facilitated by outputting a signal indicating which position detector is abnormal.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of this invention;
The figure is a time chart showing the relationship between the position detector output signal and the counter output signal, FIG. 3 is a reference diagram for explaining an example of a pattern to be stored in the memory, and FIG.
The figure is a block diagram showing a conventional example of a commutatorless motor control device. Explanation of symbols, 1... Arithmetic control unit (microcomputer), 2... Counter, 3... Waveform shaping circuit, 4, 5... Latch circuit, 6... Memory, 11
...Converter, 12...Inverter, 15...
Position detector, 16...Pulse generator.

Claims (1)

[Scope of Claims] 1. An abnormality determination device for a position detector comprising two systems of position detectors and determination means for inputting both signals and determining an output abnormality of one of the systems, wherein the position detector to be determined is: It is used to control multi-phase commutatorless motors and outputs in a logical pattern for multi-phase switching.The other position detector consists of a pulse generator and a counter that also serves as speed detection, and outputs the generator output. It counts with a counter and outputs the absolute position, and the determination means consists of a memory in which the normal position detector output pattern corresponding to the counter output is stored and a logic comparison section. A logical comparison unit compares a normal output pattern from the memory based on the position output and an output pattern from the position detector to be determined, thereby determining an abnormality and identifying the abnormal detector. Abnormality determination device for position detectors.