| 摘要 |
<p>PURPOSE:To prevent the application of an overvoltage to an inverter even when a load abruptly decreases by connecting a voltage-absorbing resistor between a rectifier and the inverter at a predetermined duty ratio when the voltage value of the output of the rectifier exceeds a predetermined reference value. CONSTITUTION:A voltage-absorbing resistor 26 is connected through a transistor 28 in parallel with an inverter 22 between a rectifier 18 and the inverter 22. To connect the resistor 26 with a circuit at a predetermined duty ratio, an overvoltage-preventing circuit 30 is provided. The preventing circuit 30 detects the output voltage of a rectifier 18 from terminals 30a, 30b, and supplies a duty control signal to the base of the transistor 28 from the terminal 30c at a duty ratio responsive to the output voltage of the rectifier 18.</p> |
