JPH0277909A - Controller - Google Patents

Abstract

PURPOSE:To obtain a stable answer of the load position when a speed command changeover switch is turned off by holding the switch of an internal speed command until the output of an integrator is equal to the load speed when a changeover switch is turned off. CONSTITUTION:A position loop computing element 1 operates a position error 11 with input of a position command 9. The error 11 is inputted to a speed loop computing element 3 by a speed command 12 via a speed command generator 2. Then a speed error 14 is inputted to an integrator 4 and an internal speed command 15 is outputted. Then a computing element 5 calculates an internal error speed 16. This signal 16 drives a load 7 via a power amplifier 16. At the same time, a changeover switch ON signal 20 is cut, an internal command changeover switch 8 is kept ON via a logic circuit 19. The command 15 is gradually increased with integration of the error 14. The command 15 is compared with the value of a load speed 13 by a comparator 18. When the coincidence is obtained between both values, a signal is sent to the circuit 19. The circuit 19 outputs the signals to turn on a switch 17 and to turn off the switch 8 respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention relates to improving the load response of a control device that controls position.

[Conventional technology]

Figure 3 is a configuration diagram of a conventional control device of the type B. In Figure 2, (1) is a position loop calculator, (2) is a speed command generator, (3) is a speed loop calculator, and (4) is a speed command generator. is an integrator.

(5) is the internal velocity loop calculation 11. (8) is a power amplifier.

(7) is the load, (8) is the speed command changeover switch, (9)
is position command, Ql is load position, 01) is position error,
a2) is the speed command, @ is the load speed, a4) is the speed error, (19 is the internal speed command, and (υ is the internal error).

Next, the operation will be explained. When the position command (9) is input, 2-position loop calculation 1 (at 11, the difference between the position command (7) and the load position α1, that is, the 2-position error θl) is calculated. The position error 01) is input to the speed command generator (2) and amplified to an appropriate magnitude to become the speed command (to).

In the speed loop calculator (3), the speed command @ and the load speed■
In other words, the speed error (4) is calculated. The speed error (factor) is integrated by the integrator (4) and the internal speed command (
The internal speed loop calculator (5) calculates the difference between the internal speed command (1) and the load speed (13), that is, the internal speed error (υ).The internal speed error (υ is the power amplifier (6) is sent to drive the load (7).The speed command changeover switch (8) is turned on when the speed error (b) becomes small to speed up the response of the control loop and further reduce the speed error (b). Therefore, the response of the control loop is slowed down to ensure stable operation, and the speed command changeover switch (8) is turned off at times.

Figure 4 (a) depicts the above series of operations as a signal waveform.
~ It will look like Figure 4(e).

[Problem to be solved by the invention]

Conventional devices of this kind are configured as described above, so that from the time when the speed command changeover switch (8) is turned off until the time when the speed command ), there was a problem that the position of the load was not stable.

This invention was made to solve the above-mentioned problems, and its purpose is to provide a control device that allows the load position (101) to respond stably when the speed command changeover switch (8) is turned off. shall be.

[Means to solve the problem]

The control device according to the present invention includes an internal speed command changeover switch installed between the integrator and the internal speed loop calculator, and a comparator that compares the magnitude of the internal speed command and the load speed, and a switch between the output of the comparator and the switch. A logic circuit is provided to control the timing of turning on and off the speed command changeover switch and the internal speed command changeover switch based on the switch-on signal.

[For production]

In this invention, the internal speed command is not input to the internal speed calculator until the output of the integrator, that is, the internal speed command reaches the load speed when the changeover switch on signal is turned off, and the speed command changeover switch is turned off. Since it is not turned off, the load position will not operate unstable even if the changeover switch on signal is turned off.

〔Example〕

FIG. 1 is a diagram showing an embodiment of the present invention.

In the figure, (1) to (l are the same as the conventional control device. () is an internal speed command changeover switch, (A) is a comparator, (A hammer is a logic circuit, and (To) is a changeover switch ON signal.

In the control device configured as described above, the operation up to the time when the changeover switch-on signal (to) is input is the same as that of the conventional control device.

Conventionally, when the changeover switch-on signal (To) is cut off, the integrator (4) generates a speed error (B), as shown in Figure 4 (e).
Because of the integration of Leave switch (8) on. Internal speed command (19 is speed error (2)
) becomes gradually larger by integrating. Compare the magnitude of this internal speed command α and the load speed ■ using a comparator.
When the sizes become equal, a signal is sent to the logic circuit (+9). This signal operates to output a signal to turn on the logic circuit (Q is the internal speed command changeover switch) and turn off the speed command changeover switch (8). By operating in this way, the internal speed loop calculation The internal speed command a9 is input to the device (5) when the internal speed command 09 becomes equal to the load speed ■.

The speed command @ will be cut off. Therefore, when the changeover switch-on signal (2) is turned off, the internal speed error (υ) will not change significantly as shown in FIG. 2(e), and the load position signal will not operate in an unstable manner.

If the above series of operations is depicted as a signal waveform, it is shown in Figure 2' (a
) to Figure 2(e).

〔Effect of the invention〕

As described above, according to the present invention, since the internal speed command is not changed until the output of the integrator becomes equal to the load speed when the changeover switch is turned off, the load position can be smoothly changed.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a control device showing an embodiment of the present invention;
FIG. 2 is a waveform diagram showing the operation of this invention. FIG. 3 is a configuration diagram of a conventional control device, and FIG. 4 is a waveform diagram showing the operation of the conventional control device. In the figure, (1) is a position loop calculator, (2) is a speed command generator, (3) is a speed loop calculator, (4) is an integrator, (
5) is an internal speed loop calculator, (6) is a power amplifier,
(7) is the load, (8) is the speed command changeover switch, (9)
is a position command. QOI is the load position, Of) is the position error, and ■ is the speed command. (13) is load speed, (capital) is speed error, (1 is internal speed command, (0 is internal speed error, (r?) is internal speed command changeover switch, (8 is comparator, (+!l) ) is a logic circuit, and ■ is a switching switch-on signal. In the two figures, the same or equivalent parts are designated by the same reference numerals.

Claims (1)

[Claims] A control device that controls the position of a load using a position command includes a position loop calculator that receives a position command and calculates a position error from the position command and the load position, a speed command generator that generates a speed command from the position error, and a speed A speed loop calculator that calculates the speed error from the command and load speed, an integrator that integrates the speed error and generates the internal speed command, an internal speed command changeover switch that inputs the output of the integrator, and a speed loop calculator that calculates the speed error from the command and load speed. An internal speed loop calculator that calculates the internal speed error by subtracting the load speed from the sum of the speed commands, a power amplifier that drives the load based on the internal speed error, and a speed switch that switches between inputting the speed command to the internal speed loop calculator. A command changeover switch, a comparator that receives the internal speed command and load speed and determines their magnitude, and a comparator that receives the output of the comparator and a changeover switch on signal to operate the internal speed command changeover switch and the speed command changeover switch. It consists of a logic circuit that controls timing, and prevents the internal speed command from being input to the internal speed loop calculator until the internal speed command approaches the magnitude of the load speed when the changeover switch on signal is no longer input. A control device characterized by reducing load speed fluctuations.