| 摘要 |
A power conversion device including an inverter which converts a direct current voltage to an alternating current voltage of any magnitude and frequency using semiconductor switches, and supplies the voltage to a load such as a motor, wherein a switch is provided in the direct current portion of the inverter. A capacitor is connected, via the switch, between a positive and a negative electrode of the direct current power source, and a constant voltage element is connected in parallel to the capacitor. A varistor, a zener diode, or an avalanche diode, or alternatively, a combination of the zener diode and a self-turn-off semiconductor element (such as an IGBT or a MOSFET), or the like, is used as the constant voltage element. Each part of the power conversion device is thereby protected against overvoltage, thus avoiding an increase in the capacitance and volume of the capacitor. |
| 主权项 |
1. A power conversion device, comprising:
an inverter which converts a voltage of a direct current power source to an alternating current voltage of arbitrary magnitude and frequency using semiconductor switches, and supplies the alternating current voltage to a load; a switch unit connected between a direct current input of the inverter and the direct current power source; a capacitor connected, via the switch unit, between a positive electrode and a negative electrode of the direct current power source; and a constant voltage element, in which a voltage difference between first and second ends thereof is regulated to a specific clamping voltage, connected in parallel to the capacitor. |
