Residual current transformer fault self-diagnosis system and method

Abstract

The present invention provides a residual current transformer fault self-diagnosis system and method. The system comprises a residual current transformer, a self-diagnosis current generation circuit,a state switching circuit, a residual current transformer main body circuit and a microcontroller. The microcontroller is connected with the self-diagnosis current generation circuit, the state switching circuit and the residual current transformer, and the self-diagnosis current generation circuit and the state switching circuit are connected with the residual current transformer respectively through a first winding and a second winding. The residual current transformer fault self-diagnosis system and method employ fractal dimensions as characteristic quantity in a measurement fault type to accurately diagnose the types of faults, so that the residual current transformer fault self-diagnosis system and method have good adaptation for tiny faults and complex faults; and moreover, the residual current transformer fault self-diagnosis system and method set a self-diagnosis cycle through control of a single chip microcomputer to perform periodic self-diagnosis so as to improve the intelligent degree of the electronic residual current transformer.

Description

technical field [0001] The invention relates to the field of intelligent electrical appliances, in particular to a residual current transformer fault self-diagnosis system and method. Background technique [0002] At present, the fault diagnosis method for the electronic residual current transformer usually adopts imitating the residual current, and judges the fault of the transformer according to the signal fed back by the transformer. By adding a self-test signal to the residual current transformer to excite the winding, an analog residual current signal that does not conflict with the actual residual current signal is provided based on the control of the single-chip microcomputer, and it is formed automatically and periodically without manual operation. [0003] These existing technologies only detect whether the residual current transformer is faulty or not, but are not clear about the type of fault detection. The intelligent electronic residual current transformer inte...

AI Technical Summary

Problems solved by technology

The intelligent electronic residual current transformer integrates a variety of electronic circuits such as residual current sampling circuit, status display circuit, signal conditioning circuit, optocoupler isolation circuit, A / D conversion circuit, microcontroller, etc., and the working environment is complex and changeable. A large number of optical and electronic devices are used in the electronic residual current transformer. This structural feature requires that it must withstand the influence of electromagnetic interference. When it works in a harsh environment for a long time, the output signal has a slight difference or is more complicated. When there is a fault, it is difficult to diagnose by traditional methods, and it cannot be diagnosed periodically and spontaneously

Images