Matching for the generator and RF cavity in HIRFL injector

This paper describes power matching of the 200 kW generator and RF cavity of HIRFL Injector RF system， working principle of matching measure system as well as matching system improvement and perfecting.It further calculates the input impedance and coupling capacitor of the RF cavity. In order to enhance the reliability and stability in RF system, the problem of D voltageenhancement and RF power transmission,etc are researched in depth. The vector impedance meter is used to measure the cavity matching impedance and the vector voltage to dynamically measure the phasing errors of the power output, then that the D circuit is working at the matching stage can be ensured. With the D voltage of SFC raising from 50~65 kV (unstable) to 105 kV (stable), SFC's high efficiency is guaranteed．