Abnormal working condition sensing algorithm and device of low-voltage power supply circuit

Abstract

The invention discloses an abnormal working condition sensing algorithm of a low-voltage power supply circuit. The abnormal working condition sensing algorithm comprises the steps of: sampling instantaneous values ia, ib, and ic of three-phase currents and the instantaneous value ir of residual current according to the set number of sampling points within each cycle, and detecting whether the waveform of ia, ib, ic or ir generates a sudden change point by point; and excluding the erroneous judgement of the low-voltage power supply circuit caused by electrical disturbances point by point: judging whether an abnormal working condition occurs in the low-voltage power supply circuit. The abnormal working condition occuring in the low-voltage power supply circuit is accurately identified, and meanwhile, the erroneous judgement caused by load fluctuations and electrical interference is excluded as much as possible, in order to reduce the performance requirements on a sensing device, a communication bandwidth and the processing capability of a cloud platform. The invention further discloses an abnormal working condition sensing device of the low-voltage power supply circuit, which can also achieve the above technical effects.

Description

technical field

[0001] The invention relates to a low-voltage power supply circuit abnormal working condition perception algorithm and a device in the field of identifying abnormal working conditions of electrical equipment. Background technique

[0002] In the low-voltage power supply system, traditional frame circuit breakers, molded case circuit breakers and miniature circuit breakers, as well as power instruments that monitor the circuits they supply, detect whether the load current or residual current exceeds the threshold, or the internal current circuit of the circuit breaker Fault detection is carried out by means of whether there is heat or not. This method can only identify a few abnormal phenomena such as circuit overload, insulation damage or circuit short circuit, but lacks sensitive identification of common abnormal conditions such as insulation deterioration, poor contact, and abnormal operation of electrical equipment, so it is also impossible to make early w...

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