JPH0464938U

JPH0464938U -

Info

Publication number: JPH0464938U
Application number: JP10933490U
Authority: JP
Priority date: 1990-10-17
Filing date: 1990-10-17
Publication date: 1992-06-04
Anticipated expiration: 2005-10-17
Also published as: JP2536985Y2

Description

[Brief explanation of the drawing]

第１図はこの考案の一実施例の開閉器の異常検
出装置のブロツク図、第２図は同実施例における
判定回路のブロツク図、第３図ａ，ｂは同実施例
における判定回路の動作を説明するための信号波
系図、第４図ａは同実施例における再発弧発生時
の各部の信号波形図、第４図ｂは同実施例におけ
る再点弧発生時の各部の信号波形図、第５図は従
来例の開閉器の異常検出装置のブロツク図、第６
図ａは従来例における信号検出器の動作を説明す
るための波形図、第６図ｂは従来例におけるＡ相
判定回路の動作を説明するための信号波形図、第
７図ａは従来例における再発弧発生時の各部の信
号波形図、第７図ｂは従来例における再点弧発生
時の各部の信号波形図である。３……負荷、４……開閉器、５……開閉器の異
常検出装置、６Ａ，６Ｂ，６Ｃ……電流検出部、
７……変換回路、８……判定回路、２１……信号
検出器、２２……積分回路、２３……加算器、２
４……第１のコンパレータ、２５……第１の時間
測定判定回路、２６……アンド回路、２７……減
算器、２８……第２のコンパレータ、２９……第
２の時間測定判定回路、ａ……警報信号、ｂ……
再発弧信号、ｃ……再点弧信号。 Fig. 1 is a block diagram of an abnormality detection device for a switch according to an embodiment of this invention, Fig. 2 is a block diagram of a judgment circuit in the same embodiment, and Figs. 3a and b are operation of the judgment circuit in the same embodiment. FIG. 4a is a signal waveform diagram of each part when a re-ignition occurs in the same embodiment, FIG. 4b is a signal waveform diagram of each part when a re-ignition occurs in the same embodiment, Figure 5 is a block diagram of a conventional switch abnormality detection device;
Figure a is a waveform diagram for explaining the operation of the signal detector in the conventional example, Figure 6b is a signal waveform diagram for explaining the operation of the A phase determination circuit in the conventional example, and Figure 7a is the waveform diagram for explaining the operation of the A phase determination circuit in the conventional example. FIG. 7b is a signal waveform diagram of various parts when a re-ignition occurs in a conventional example. 3...Load, 4...Switch, 5...Switch abnormality detection device, 6A, 6B, 6C...Current detection unit,
7... Conversion circuit, 8... Judgment circuit, 21... Signal detector, 22... Integrating circuit, 23... Adder, 2
4...First comparator, 25...First time measurement judgment circuit, 26...AND circuit, 27...Subtractor, 28...Second comparator, 29...Second time measurement judgment circuit, a... Alarm signal, b...
Re-ignition signal, c... Re-ignition signal.

Claims

[Scope of Claim for Utility Model Registration] (1) A current detection section that detects the load current values of three phases, and a current that is obtained by full-wave rectification of the current detected by the current detection section of each phase and summed for each phase. a conversion circuit that outputs a voltage value corresponding to the voltage value as a conversion signal; and a conversion circuit that detects a cutoff signal of a switchgear and detects that the cutoff signal is high and the conversion signal output from the conversion circuit exceeds an upper limit specified value. An abnormality detection device for a switchgear, comprising a determination circuit that issues an alarm signal when the time exceeds a set time. (2) a signal detector that detects the shutoff signal of the switchgear; an integrating circuit that has a large time constant and integrates the conversion signal that is the output of the conversion circuit; and a first constant value for the output voltage of the integrating circuit. an adder that outputs a specified upper limit value obtained by adding the specified upper limit value; and an adder that compares the specified upper limit value outputted by this adder with the conversion signal of the conversion circuit, and generates an upper limit detection signal when the converted signal exceeds the specified upper limit value. a first time measurement judgment circuit that measures the duration of the upper limit detection signal of the first comparator and generates a time excess signal when the duration exceeds a set time; Claim 1, further comprising a determination circuit comprising an AND circuit that issues an alarm signal when the cutoff signal of the detector is high and the time excess signal of the first time measurement determination circuit is high. Abnormality detection device for switchgear. (3) a subtracter that outputs a lower limit specified value obtained by subtracting a second constant value from the output voltage of the integrator circuit; and a subtracter that outputs a lower limit specified value obtained by subtracting a second constant value from the output voltage of the integrator circuit, and compares the lower limit specified value of this subtracter with the conversion signal of the conversion circuit, and A second signal that generates a lower limit detection signal when the lower limit value becomes smaller than the specified lower limit value.
a comparator, and measures the duration of the lower limit detection signal of this second comparator, generates a re-ignition signal when this duration is less than a predetermined value, and when the duration exceeds the predetermined value. A second circuit that generates a restrike signal
2. The abnormality detection device for a switchgear according to claim 2, further comprising a time measurement determination circuit.