The invention discloses an
inrush current restraining
system and method based on residual
magnetism prediction and
circuit breaker discreteness improvement. According to the
inrush current restraining method, real-time operation conditions of a
transformer are monitored on line, the
hysteresis loop of an iron core is calculated according to a JA module, the residual
magnetism value of the
transformer when the
transformer is switched off is obtained, the residual
magnetism inside the iron core of the transformer and the magnetic bias are opposite in direction through control over the switch-on angle, the no-load excitation
inrush current of the transformer is restrained, and a feedback mechanism is introduced into the inrush current restraining process. Compared with the prior art, a hardware
system can be universal; in the no-load switching process of the transformer, no-load excitation inrush current can be effectively restrained, and operation of an
electric transport system is made stable and reliable; residual magnetism prediction is introduced, calculation of the switch-on angle is more accurate; the feedback mechanism is introduced into the inrush current restraining process, and the system can automatically adapt to aging of a
circuit breaker and changes in the external environment, so that the accuracy and reliability of the system are improved, and the inrush current restraining effect is realized.