JPH0323830Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a fixed position stop device, particularly one using the thyristor Leonard system.

The thyristor Leonard type fixed position stop device is
A new position control system is added to the general speed control system with a current minor loop, resulting in high precision and
It is widely known for its high speed, stability, and excellent stopping characteristics.

The purpose of this invention is to further improve the control characteristics of this thyristor Leonard fixed position stop device. The purpose of this invention is to realize a fixed position stopping device with excellent characteristics in terms of both high speed and stability, and the details will be specifically explained below based on an embodiment shown in the drawings.

As for the drawings, Fig. 1 is a block diagram of the thyristor Leonard fixed position stop device, Fig. 2 is a block diagram of the position control system and speed control system of the above overall block diagram, and Fig. 3 shows the relationship between the rotating body and the sensor. FIG. 4 is a sensor output diagram, and FIG. 5 is a time chart showing the operation of the embodiment of the present invention.

As shown in Fig. 1, the thyristor Leonard fixed position stop device consists of a speed control system having a DC motor 21, a thyristor device 22, a thyristor driver 23, and a current control system I in a minor loop, and a fixed position stop device which is the purpose of this invention. It is equipped with a position control system for accurate stopping. This position control system is of course disconnected during normal operation, and commands are given to the speed control system from a speed setter (not shown), so that the system operates as a general speed control system with a current minor loop. In other words, to stop the rotating body at a fixed position, after disconnecting the speed setting device of the speed control system,
A position control system is inserted, and the output of this position control system is added as a command to the speed control system, but the present invention changes the operation mode of the position control system and speed control system according to the stop position deviation and rotating body speed. The aim is to obtain better stop control characteristics by switching between the two.

In other words, the position control according to this invention is
At the start of positioning, the speed command of the speed control system is set to zero to reduce the speed of the rotating body, and once the rotating body has decreased to the predetermined positioning speed, the adjuster of the position control system is turned on. Proportional control is performed, and a bias signal is applied to rotate the rotating body at a constant value of the above-mentioned positioning speed. Also, preparations are made to accept the sensor output when the rotating body passes the stop position sensor location, and furthermore, the above-mentioned sensor output is accepted. After a certain period of time, the timer is activated, and after a certain period of time, the position control system bias signal is reduced and the rotating body is operated at a slow speed in order to stop at an arbitrary point.At the final stopping point, the position control system is activated by the positive rise of the sensor output. Switch the regulator to proportional-integral control, increase the speed detector gain of the speed control system, and when the sensor output falls within the allowable stopping point, switch the gain of the proportional-integral regulator to zero to ensure accurate positioning. This realizes a smooth stop.

FIGS. 2 to 5 show an embodiment of the present invention described above, and will be specifically described below with reference to these drawings. Figure 2 is a detailed block diagram of the speed control system and position control system.
It is composed of a speed setter 3 that gives a speed command, and a switch element X7 that disconnects the speed setter 3 from the system and sets the speed command to zero. On the other hand, the position control system includes switch elements X1 and X2, and the regulator 4 is connected to P
controller, PI controller, and 2
It is composed of switch elements X4 and X5 that turn on and off two bias signals, and a switch element X6 that is equipped with bias signal setters 5 and 6 and determines whether or not to accept the output from the sensor that detects the stop position. . Further, as shown in FIG. 3, the above-mentioned sensor for detecting the stop position of the rotating body is of a type in which a magnet or the like 11 is provided at a certain location on the rotating body 10, and the magnetism is detected by a magnetic sensor 12 on the fixed side. The relationship between the position of the rotating body and the sensor output has a substantially positive and negative sinusoidal waveform as shown in FIG.

Although the configuration of the present invention is as described above, its operation will be explained next. That is, to describe the case where the rotating body is stopped at a fixed position from a state in which it is rotating at a normal speed, first, a positioning start command is issued, the switch element X7 is closed, and the speed setting device 3 is turned on. Disconnect from the system and set the speed command to zero. As a result, the rotating body speed decreases, but when it reaches a predetermined speed, the positioning speed, the comparator 7 is activated and the position control system is introduced into the system. That is, in the position control system, during normal operation, the switch element X3 is closed and disconnected from the system, but when the comparator 7 is activated, the switch element X3 is opened.
and other switch elements X4 and X5 for applying bias signals corresponding to position speeds, switch element X6 for receiving the stop position detection sensor output, and switch element X for operating the regulator as a P regulator.
1 are switched to the operating state, and therefore, the position control system is a proportional control system and supplies a speed command input to the speed control system to rotate the rotating body at a constant speed of the positioning speed. If a sensor output is input while the rotating body is rotating at this positioning speed, the timer is activated from the negative fall of the output, and after a certain period of time (Tsec) the switch element
4 is opened, and the first bias signal setter 5 is separated from the position control system. That is, the control system is connected only to the second bias signal setting device 6, and its output controls the rotating body to a slow rotation speed that makes it easy to stop the rotating body at an arbitrary point. This timer time Tsec is selected to be approximately one rotation time from the rise of the sensor output to the reception of the next sensor output while the rotating body is driven at a constant position speed. Make it easy to stop. Thus, after the timer time Tsec,
The output of the position control system is a slow speed command value, and the rotating body is controlled to rotate at an extremely low speed, and it receives the sensor output in this state. At the positive rise of this sensor output, the switch element The bias signal setting device 6 is also separated from the system,
And the switch elements X1 and X2 are opened and closed, respectively, the position control system is switched from the proportional control system to the proportional integral control system, and the input becomes only the sensor output, and furthermore, the switch element X8 of the speed control system is opened, Increase the gain of proportional regulator 2,
Increase the speed feedback signal from the speed detector.

In this way, in the position control system, all bias signals are blocked and only the sensor output is input.
In addition, the P control system has been switched to the PI control system, which has zero steady-state deviation, so its output decreases over time, and the speed of the rotating body also decreases.
As a result, the sensor output also has a waveform as shown in FIG. 5, causing a further decrease in the rotating body speed. In this state, when the sensor output reaches a value within the predetermined stopping accuracy, the switch element Stop at a fixed position within this allowable stopping accuracy.

The time chart in Figure 5 shows, from top to bottom, stop position detection sensor output waveform A, positioning start command B, speed detector output signal waveform C, position control system output signal waveform D, and speed command output short circuit switch element X7. Operation waveform E, position control system output short circuit switch element X3 operation waveform, sensor output acceptance/disapproval switch element X6 operation waveform G,...
Operation waveform of switch element X1 for operating the position control system as a proportional control system, operation waveform of first bias signal setter 5 closing/closing switch element X4, operation of second bias signal setting device 6 closing/closing switch element X5 Waveform N, operating waveform of switch element X2 for operating the position control system as a proportional-integral control system, and operating waveform of switch element It is a diagram illustrating a position stop control operation.

As mentioned above, this invention has the advantage of setting the speed setter command to zero when starting positioning, connecting the position control system instead, and decelerating and stopping the rotating body using the output from the stop position sensor. There is no difference from the conventional example, but during the stopping process, the position control system output is gradually lowered by switching the bias signal, etc., and when the sensor output rises just before the stop position, the position control system itself The control mode of the P control system is switched from the P control system to the PI control system, and the speed feedback signal gain of the speed control system is increased. Furthermore, when the sensor output falls within the predetermined allowable stop accuracy, the position control system regulator is switched on. The feature is that the outputs are shorted, the position control system output is set to zero, and the rotating body is stopped at a position within the above-mentioned stopping accuracy, so the position control system and speed control are adjusted according to the position and speed of the rotating body. As a result, high-speed rotation can be maintained until close to the stop position, and since the stop control is performed by the PI control system, the steady-state deviation is zero, resulting in high accuracy. Furthermore, at a position within the stop accuracy, the speed control system It can be stopped with good stability by reducing the input to zero.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the thyristor Leonard fixed position stop device, Fig. 2 is a detailed circuit diagram of the position control system and speed control system of the embodiment of the present invention, Fig. 3 is a diagram showing the relationship between the rotating body and the sensor, FIG. 4 shows a sensor output diagram, and FIG. 5 shows a time chart for explaining the operation of the above embodiment. ...speed control system, ...position control system,
2...Speed control system P adjuster, 3...Speed setter,
4...Position control system adjuster, 5...First bias signal setter, 6...Second bias signal setter, 7...Positioning speed detector, X1
... Switch element for proportional control, X2 ... Switch element for proportional integral control, X3 ... Switch element for position control system output short circuit, X4 ... Switch element for first bias signal, X5 ... Second bias signal X6...Switch element for sensor output acceptance/disapproval, X7...Switch element for speed command output short circuit, X8...Switch element for speed detector gain switching.

Claims (1)

[Claims for Utility Model Registration] In a fixed position stop device that includes a DC motor controlled by phase shift adjustment of a thyristor, a speed control system with a current control system in the minor loop, and a position control system outside of the speed control system, the above-mentioned speed The control system includes a PI controller 1, a P controller 2 which is connected to the input side of the PI controller in parallel with the position control system and has a gain switching function, and a P controller 2 that is connected to the input side of the PI controller in parallel with the position control system and has a gain switching function. a speed setter 3 connected via a switch element X7 so as to be disconnected from the
TG, and the above-mentioned position control system includes a P-operation or PI-operation regulator 4, which separates the speed setting device 3 from the system and turns on when the rotating body speed decreases to the positioning speed. , bias signal setters 5 and 6 that can set at least two high and low positioning bias signals, and a magnet 11 attached to a rotating body that outputs a positive and negative substantially sinusoidal waveform signal during positioning. and a stop position detection sensor consisting of a magnetic sensor 12 installed on the fixed side, and the bias signal setting devices 5 and 6 are
A switch element X4 switches the setting of the bias signal from high to low after a predetermined period of time after the negative fall of the stop position detection sensor output signal, and the bias signal is also set at the subsequent positive rise of the sensor output signal. A switch element X5 for separating the
The regulator 4 includes a switch element X that switches from P operation to PI operation at the positive rising edge of the sensor output signal.
1, X2, and a switch element X3 that inhibits PI operation when the magnitude of the sensor output signal falls within a predetermined stopping accuracy.