In this paper, the circuit of high frequency power supply for the electrode-less discharge lamp is proposed. In order to obtain the high power, the circuit is made by combining outputs of parallel four 125W power conversion circuits. This method is effective in order to make the high power circuit with the low cost in small space. The design of 500W-class high frequency power supply for electrode-less discharge lamp with 2.6MHz is reported. The electric power transmission from the power supply to the load carried out using coaxial cable. The control circuit for operating the lighting equipment in the high reliability is also reported.
