This paper presents a new way of using nonlinear network to change frequency for high-frequency power source. It is proved by computer-aided analysis and experimental demonstration that such high-frequency power source is featured by high efficiency

low cost

convenient load matching

easy maintenance

etc.

and is very suitable for induction heating. This prototype has already been put into industrial operation. The technical data of the prototype is given at the end of the paper: a rated power of 150 kW

output frequency of 25-63 kHz

electric efficiency of 90.5%

and output frequency modulation characteristic

etc.

In the prototype

just by changing load parameters

any needed frequency can be obtained conveniently at 25-63 kHz while keeping the rated power

without changing the internal network parameters and input frequency. This feature does not exist in power sources using other ways to change frequency. Theoretical analysis and the mathematical model are given for such a high step nonlinear network. It is expected that with the aid of the general computing routine of a digital computer

the optimization design of series products can be realized

thus ensuring its wide applications.