| 摘要 |
PURPOSE: To suppress overvoltage when a switching element is turned on/off using small number of components. CONSTITUTION: An overvoltage suppression circuit comprising a diode Dc, a capacitor Cc and a resistor Rc is connected between DC buses PN for an inverter. The discharge resistor Rc is connected, at one end thereof, with the DC bus side of an anode reactor and the current from the reactor La is circulated through the diode Dc and the resistor Rc when a GTO is turned on thus suppressing the overvoltage. This circuitry eliminates the needs of diode and resistor conventionally connected in parallel with the reactor La in order to circulate the reactor current. |
