| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-frequency power supply unit for supplying high-frequency to a load capable of protecting the load by meeting abrupt changes in the load impedance. <P>SOLUTION: A luminescent and wide-gap bipolar semiconductor control element, radiating light with intensity proportional to the energized current, is used for the switching element of an inverter generating high-frequency power to detect the radiated light. The increase in the energized current, when load impedance is decreased, is detected by an increase in the intensity of light, and a capacitor in a filter circuit is discharged by the detected signal, high-frequency power is made to decrease at a high speed. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
