| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high frequency power supply device which precisely controls to maintain a power value of high frequency power at a set value even when a frequency of the high frequency power supplied to a load is changed. <P>SOLUTION: The high frequency power supply device includes a first and second high frequency generation parts 101, 102 for respectively generating a first and second high frequency signal, a frequency control part 104 for giving a frequency instruction to both of the high frequency generation parts so as to maintain a difference of frequencies of both of the high frequency signals constant, a power amplification part 105 for amplifying the first high frequency signal, a multiplying part 107 for multiplying a detection signal of travelling wave power and the second high frequency signal and obtaining a signal containing a frequency component of the difference of the frequencies of both of the high frequency signals, a filter 109 for extracting a difference frequency signal having the frequency component of the difference from an output of the multiplying part, and a level control part 112 for giving an amplitude instruction to the first high frequency generation part 105 so as to maintain the travelling wave power at the set value based on a result of comparison operation of a level of the difference frequency signal extracted by the filter and a set level. <P>COPYRIGHT: (C)2010,JPO&INPIT |
