抄録
Electric railway vehicles now use regenerative brake for normal operation from the top to almost zero speed. As the electrical brake force in the high-speed range is smaller than that in the middle- or low-speed range, however, it cannot sufficiently provide the required brake power. This is because the terminal voltage of inverter cannot exceed the withstand voltage of semiconductor devices. At present, the brake force in the highspeed range mainly depends on the mechanical brake. This causes brake shoe wear and requires maintenance work. We propose to insert an adequate capacitance between inverter and traction induction motor, in order to raise the terminal power factor of the inverter. This method considerably increases electrical brake force and regeneration rate in the high-speed range. Furthermore, this method doesn't need to increase the rated power or the current of the inverter. We show simulation results of this method.
