Power supply is a key component of thyristor triggering devices for pulsed power systems. Based on the triggering requirements of high power thyristor, the trigger circuit is designed. The system use super capacitor as a power supply to meet the trigger circuit power supply voltage requirements. To carry out multiple thyristor trigger test, in order to obtain the super capacitor charge and discharge characteristics, repeatedly test multiple sets of different capacity,and select the appropriate capacity of the trigger power. The experimental results show that the trigger device can be reliably triggered to meet the design requirements; select five groups of super capacitor power supply to meet the trigger time requirements.