| 摘要 |
<P>PROBLEM TO BE SOLVED: To previously prevent the regenerative energy in a load from being rapidly increased due to fluctuation in input voltage from an alternating-current power supply. <P>SOLUTION: When a regenerative voltage applied to an inverter circuit 4 becomes equal to or higher than a preset upper limit level, a load 2 supplied with power from a rectifying and smoothing circuit 9 turns on a regenerative current switch 6 to pass a regenerative current through a regenerative current discharging resistor 5. A gate control circuit 11 carries out switching control. That is, the gate control circuit turns on a triac 8 each time a supply voltage detected by a first voltage detection circuit 10 drops to a preset target voltage level after it reaches its peak and keeps the triac on until the supply voltage is zeroed. Thus, the rectifying and smoothing circuit 9 is so controlled that its input voltage becomes equal to or lower than a target voltage level. <P>COPYRIGHT: (C)2007,JPO&INPIT |
