Analysis and Experimental Study of Impedance Matching Characteristic of RF Ion Source on Neutral Beam Injector

The impedance matching circuit is the important unit for the RF ion source, which is used to match the electric parameters of the RF generator and ion source antenna in order to transfer the RF power to the RF antenna of ion source and to get stable plasma. The plasma impedance will be changed during the plasma generation, since the impedance characteristic is not easy to be calculated and measured; it also necessary to do more experimental study. In this paper, the impedance matching unit was analyzed and designed according to the principle of RF ion source. The matching characteristic was studied during the experiment, and we achieved the best impedance matching characteristic. It also verified the good design of impedance matching unit. Based on the results of impedance matching studies, high-RF stable plasma discharge was achieved.