High frequency power transmission by lumped constant circuit replaced distributed constant line

In a high-frequency induction heating system with a operating frequency ranged over megahertz, the wiring between the voltage-fed-type inverter and a parallel LC resonant load circuit causes the deterioration of the electric power transmission characteristics. To solve this problem, the authors have developed a power transmission method using the distributed constant line (DCL) with 1/4 length of the wavelength determined by LC resonant frequency. The line is connected between the voltage-fed-type inverter and a parallel LC resonant load circuit. However, when the load is placed near the inverter set, this method is not as cost-effective because of the high expense and long length of the DCL. The authors studied a novel method with the LC lumped constant circuit replacing the DCL for transmission of high-frequency electric power ranged over megahertz. Experimental results indicate that the waveform of the inverter output current is approximately sinusoidal with a small amount of high harmonics, which is smaller than the result obtained with the DCL