High-frequency power source

A high-frequency power source for supplying high-frequency power to a load in which a reflection characteristic for the high-frequency power varies with time, the power source comprising:

• a frequency-variable power generator for generating the high-frequency power;
• a power detector for detecting a high-frequency power which goes into the load and a high-frequency power which is reflected by the load;
• a reflection coefficient calculator for calculating a reflection coefficient based on the detection by the power detector of the power which goes into the load and the power which is reflected by the load;
• a frequency detector causing the power generator to generate high-frequency powers at various frequencies within a predetermined frequency range for obtaining a frequency that gives a minimum value to the reflection coefficient calculated by the reflection coefficient calculator;
• and
• a power supply controller for causing the power generator to generate a high-frequency power of the frequency obtained by the frequency detector and for supplying the high-frequency power to the load.