JPS629402A - Electrical signal switching device - Google Patents

Abstract

PURPOSE:To prevent the disturbance due to a changeover switch by providing a rate limiter to correct an instantaneous signal change produced when the process signal sent from a power plant is switched. CONSTITUTION:The input process signals are selected or switched by a changeover switch 1 like an analog switch, etc. A rate limiter 4 is actuated to perform the connection of two signals at an optional changing rate. This can correct the instantaneous signal change produced when said process signal is switched. As a result, the switching branch point of the process signal is smoothed and the continuous signals are obtained. Then the disturbance due to the switch 1 can be avoided. Here it is not needed to set a controller 2 into a manual mode as long as no disturbance is given to the process.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrical signal switching device for switching process signals in a power generation plant, and particularly to prevention of disturbance during switching.

[Conventional technology]

FIG. 2 is a block diagram showing the configuration of an electrical signal switching device including a signal switching device and a controller for switching the process signal 1 of a power generation plant, for example.

In the figure, 1 is a changeover switch that is installed in a central control room, etc., and selects and switches electrical process signals, and 2 is a controller that can switch between manual mode and automatic mode and sets the amount of operation. be.

Next, the operation will be explained. When the manipulated variable is set by the controller 2, if a certain process signal 3 becomes abnormal, another process signal 3 is selected.

In this case, process signal 3 is selected with changeover switch 1, but in order not to disturb the process, the controller 2 is set to manual mode in advance, and the above selection is made after confirming that the signal after switching is normal. Let's do it. After the above operations, the controller 2 is set to automatic mode.

[Problem that the invention seeks to solve]

Conventional electrical signal switching devices are configured as described above, so the controller must be set to manual mode when switching, and it is necessary to confirm that it does not disturb the process. There were very few problems with this.

This invention was made in order to eliminate the problems of the conventional ones as described above, and it improves the large rate of change when switching signals by a changeover switch, and allows continuous system input signals to respond to rapid changes. An object of the present invention is to obtain an electrical signal switching device that can perform signal switching.

[Means for solving problems]

The electrical signal switching device according to the present invention manually inputs a plurality of process signals using a changeover switch, and combines the two signals at an arbitrary rate of change in order to correct the instantaneous signal change that occurs when the signals are switched. It is equipped with a limiter and outputs a corrected signal according to the operation amount set in the controller.

[Function] In the electrical signal switching device of the present invention, the rate limiter smoothes the switching branch points of the process signal input to the electrical signal switching device to make it a continuous signal, thereby preventing disturbances caused by the changeover switch.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is a changeover switch such as a general-purpose analog switch, 2 is a controller, 3 is a process signal input to the changeover switch 1 and the controller 2, and 4 is a rate limiter that regulates the rate of change of the signal.

In the electrical signal switching device having the above configuration, selection or switching of input signals is performed by the above-mentioned changeover switch, which is an analog switch or the like. The selected signal is valid as a system input as long as it does not exceed the allowable range. However, when switching is performed using a changeover switch due to necessity, an instantaneous signal change occurs, so in order to correct this, the rate limiter 4 is operated to combine the two signals at an arbitrary rate of change. Further, at this time, the controller 2 does not need to be in manual mode as long as it does not disturb the process.

In addition, in the above embodiment, the case of a changeover switch using a general-purpose analog switch for signal switching was explained, but if automation of the switching function is taken into account, a conventional signal selector may also be used, and the same effect can be achieved. play.

〔Effect of the invention〕

As described above, according to the present invention, the electrical signal switching device is configured to include a changeover switch, a rate limiter that corrects instantaneous signal changes caused by switching of the changeover switch, and a controller.

This has the effect of preventing signal disturbance due to switching of the changeover switch, and saving labor in the operation of switching the controller to manual mode.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an electrical signal switching device according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a conventional electrical signal switching device. In the figure, 1 is a changeover switch, 2 is a controller, 3 is a process signal, and 4 is a rate limiter. Note that the same reference numerals in each figure indicate the same or corresponding parts. Figure 1 Input Eka 3: Buguchi Portrait

Claims (2)

[Claims] (1) A changeover switch that captures multiple process signals and selects them one by one, a rate limiter that corrects instantaneous signal changes that occur when the process signals are switched by this changeover switch, and a signal that is input from this rate limiter is set. An electrical signal switching device equipped with a controller that outputs an output according to the manipulated variable. (2) The electrical signal switching device according to claim 1, wherein the changeover switch is an analog switch.