A vacuum switch trigger generator with a low-voltage storage capacitor switched by a thyristor

An improved pulse generator for triggering a vacuum switch is designed. The generator is based on the discharge of a storage capacitor to a trigger gap of the vacuum switch through a pulse step-up transformer. It differs from analogs in an additional capacitor introduced at the output of the transformer. The pulse charging of the additional capacitor allows one to increase the amplitude of the output voltage (in practice, by a factor of over 1.7). This provides a decrease in the transformer ratio for obtaining the specified output voltage and in the value and rise rate of the primary-circuit current to levels, allowing one to use cheap standard thyristors as a switch. The description of the generator, designed for triggering high-current vacuum switches, which are used in switching systems of capacitor banks with an energy storage of 30-100 kJ and discharge-current rise times of 100-250 mu s, is given. The generator provides voltage pulses with amplitudes of > 5 kV and, after the breakdown of the trigger gap of the vacuum switch, the trigger current in the form of a damped sine wave with an amplitude of over 600 A and a total duration of up to 90 mu s.