Damping control method of regenerative brake control under light load condition utilizing over voltage resistor

Abstract

Higher DC-link voltage of the regenerating train under light-load regenerative brake control increases the regenerative brake power. However, if the regenerating load changes suddenly, the delay in the motor current control causes the filter capacitor (FC) voltage of the traction inverter increases and may activate the over voltage protection. This paper proposes a damping control method to reduce the peak of FC voltage using the over voltage resistor (OVRe). The proposed method is verified by numerical simulation assuming an actual railway vehicle under the condition of load shutdown at the highest power region, as the worst case conditions. By means of this method, the OVRe can be effectively utilized to reduce the FC voltage spike that results in more saving the substation energy.