JPH0516549B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a voltage detection device, and particularly to a voltage detection device used to detect the presence or absence of a power system primary voltage in special high voltage or ultra-high voltage power receiving equipment. be.

[Technical background of the invention]

Special high voltage or ultra-high voltage power receiving equipment is equipped with a grounding device to prevent electric shock accidents during maintenance of the power receiving point. A voltage detection device is a device that detects the presence or absence of a system's primary voltage in order to prevent ground faults caused by incorrect operation of the grounding device, and is essential for the safe operation of power receiving equipment. FIG. 1 is a block diagram of a conventional voltage detection device.

In Fig. 1, 1-1 and 1-2 are duplicated detection circuits that detect the presence or absence of grid primary voltage (hereinafter, the presence of voltage is called charging, and the case of no voltage is called non-charging). ing. 2 is the detection circuit 1-1 and 1
A comparison/judgment circuit that compares and judges the outputs of -2 and 2.
If the outputs of the two detection circuits match, a charging or non-charging indication will be displayed, and if they do not match, an alarm display will be output. Reference numeral 3 designates a simulated input circuit which individually supplies a simulated input signal of charging or non-charging to the detection circuits 1-1 and 1-2. Reference numeral 4 denotes a check circuit for providing a simulated input signal to the check circuit.

[Problems with background technology]

In the voltage detection device having the above configuration, when either the detection circuit 1-1 or 1-2 fails and the outputs become inconsistent, the comparison and determination circuit 2 outputs a failure indication. However, even though the faulty circuit is only one of the redundant circuits, the display on the voltage detection device becomes a warning display, so the function to detect whether the system is charging or not is lost. Further, since there is no way to know which of the detection circuits 1-1 or 1-2 has failed, there is a drawback that it takes time to investigate and restore.

[Purpose of the invention]

The present invention has been made with the aim of solving the above-mentioned problems, and aims to provide a voltage detection device that can determine the failure location when a failure occurs and maintain its function using only healthy circuits. .

[Summary of the invention]

In the present invention, a switching circuit is provided between the duplicated detection circuit and the comparison/judgment circuit to switch the output of one detection circuit to both inputs to the comparison/judgment circuit when a failure occurs, and only the healthy circuit is provided. We use this to maintain functionality.

[Embodiments of the invention]

Examples will be described below with reference to the drawings. FIG. 2 is a block diagram of an embodiment of the voltage detection device according to the present invention. Reference numerals 1-1, 1-2, 2, 3, 4 and 5 in the figure correspond to those in FIG.

In FIG. 2, a switching circuit 5 is provided between the duplicated detection circuits 1-1, 1-2 and the comparison/judgment circuit 2. The switching circuit 5 has contacts #2 and #3 on both sides of the #1 contact, and when connected to the #1 contact, the duplicated detection circuits 1-1 and Both inputs of the detection circuit 1-2 are introduced into the comparison judgment circuit 2, and when connected to the #2 contact, only one input of the detection circuit 1-1 is input, and when it is further connected to the #3 contact, It has a configuration in which the input of only the other detection circuit 1-2 is individually introduced.

FIG. 3 is a flowchart illustrating the determination and recovery of a failure location, and describes a series of operations when an abnormality is discovered.

First, when an abnormality is found in step 7, the switching circuit 5 is switched to #2 in step 8, and in step 9, one of the detection circuits 1-1 is charged and uncharged with a simulated input signal and displayed. confirm. If the display at that time matches the simulated input signal, the detection circuit 1-1 is normal, so proceed to step 11, switch the switching circuit 5 to #3, and then switch the other detection circuit 1-2 to step 12. On the other hand, as above, check the display by charging and uncharging the simulated input signal. If the display is abnormal in step 13, it can be determined in step 17 that the detection circuit 1-2 has failed, so in step 18 the switching circuit 5 is switched to #2 to use only the normal detection circuit 1-1. Therefore, it is possible to maintain the functionality of the voltage detection device.

If it is determined to be normal in step 13, the detection circuits 1-1 and 1- are activated in step 14 as described above.
2 is normal, so #1 contact (normal usage position)
Since it can be determined that there is a contact failure, the function can be maintained by switching the switching circuit 5 to #2 or #3 in step 15.

On the other hand, if it is determined in step 10 that there is an abnormality, the switching circuit 5 is switched to #3 in step 20, and the function of the detection circuit 1-2 is determined in step 21. If the detection circuit 1-1 is determined to be normal in step 22, it is presumed that the detection circuit 1-1 has failed in step 23, and therefore, in step 24, the switching circuit 5 is switched to #3 to use the normal detection circuit 1-2. In this case as well, functionality can be maintained. Furthermore, if it is determined in step 22 that the detection circuits 1-1 and 1-2 are abnormal, all functions are stopped in step 26 since both detection circuits 1-1 and 1-2 are abnormal.

If you proceed to step 26, it will be determined that there is some other failure, such as a poor contact in the inspection circuit 5 or a failure in the comparison/judgment circuit 2, and the function cannot be maintained, but the time required for maintenance will be shortened because the location of the failure can be determined. be able to.

FIG. 4 is a block diagram of another embodiment of the voltage detecting device according to the present invention.

In this embodiment, the above-described series of operations and check functions are automatically performed to maintain the functions.

Reference numerals 1-1, 1-2, and 2 to 5 in the figure correspond to those in FIG. It should be noted that the inspection circuit 4 and the switching circuit 5 are automatically switchable circuits, and are composed of, for example, an auxiliary relay or an analog switch. Reference numeral 6 denotes an automatic check circuit which has a function of sequentially combining the respective input conditions of the simulation input circuit 3, check circuit 4 and switching circuit 5, respectively, and further checking the output from the comparison/judgment circuit.

〔Effect of the invention〕

As explained above, according to the present invention, the fault location can be determined when a fault occurs, so it is possible to maintain the voltage detection function using only healthy circuits. Moreover, as a result, the recovery time from a failure can be shortened and the operating rate can be improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional voltage detection device, FIG. 2 is a block diagram of an embodiment of the voltage detection device according to the present invention, FIG. FIG. 7 is a block diagram of another embodiment of the voltage detection device according to the invention. 1-1, 1-2...detection circuit, 2...comparison judgment circuit, 3...simulation input circuit, 4...inspection circuit, 5
...Switching circuit, 6...Automatic inspection circuit.

Claims (1)

[Claims] 1. A duplicated detection circuit that detects a system primary voltage, a simulated input circuit that generates a simulated input signal of the system primary voltage, and a simulated input signal that is connected to the duplicated detection circuit. an inspection circuit that switches the voltage to the system primary voltage and inputs it, and a comparison judgment circuit that receives both outputs of each of the detection circuits as input and constantly monitors by determining the presence or absence of both inputs and whether or not both inputs match. A voltage detection device comprising: a switching circuit between the duplicated detection circuit and the comparison/judgment circuit, which switches the output of one detection circuit to both inputs to the comparison/judgment circuit when a failure occurs. A voltage detection device characterized by: 2. A duplicated detection circuit that detects the system primary voltage, a simulated input circuit that generates a simulated input signal of the system primary voltage, and a system that switches the simulated input signal to the system primary voltage in the duplicated detection circuit. In the voltage detection device, the voltage detection device is composed of an inspection circuit that receives input from the detection circuit, and a comparison and judgment circuit that receives both outputs of each of the detection circuits as input and performs constant monitoring by determining the presence or absence of both inputs and whether or not the two inputs match. , a switching circuit is provided between the duplicated detection circuit and the comparison/judgment circuit for switching the output of one of the detection circuits to be used as both inputs to the comparison/judgment circuit when a failure occurs; A voltage detection device characterized by comprising an automatic inspection circuit that sequentially combines and outputs each condition.