Robust convergence of the impedance matching process based on seek control

This paper is concerning a new impedance matching method used in the plasma processing, and also for wireless power transmission. RF electricity is supplied to the plasma chamber and stabile operation is required. For this purpose the equivalent impedance of the loads is controlled to be 50 Ω. Therefore the capacitance of the capacitor in an LC circuit called a matching box is adjusted so that the receiving end impedance is maintained to be 50 Ω. In this paper a novel control method of an impedance matching is proposed and the successful experimental results are presented. A modification of the rate change of the matching elements improves the convergence time.