Abstract:

At present,the closing coil power supply mode of the operating mechanism of the locomotive vacuum circuit breaker is divided into energy storage capacitor power supply and DC power supply.Since the closing process requires short-term large current and large DC power supply,the use of energy storage capacitor as the closing coil power supply has become the mainstream.In order to eliminate the way of series resistor limiting the charging current,the fuzzy control method is used to output PWM waveform to control the charging voltage of capacitor,making the charging current waveform basically constant and reducing the loss of energy on the current limiting resistor.The charging current can be flexibly adjusted by adjusting the set value.To test and verify the feasibility of fuzzy control,a fuzzy control system and the main circuit are built in Simulink to simulate the charging process.The simulation results show that by adjusting the IGBT duty cycle it achieved the capacitance of the constant current charging,which can avoid the large current shock,increase the service life of the energy storage capacitor,reduce the locomotive energy storage failure caused by frequent a closing phase points.

Key words: locomotive, energy storage capacitor, fuzzy control, constant current