The influence of mode switching on voltage stability and current ripple control of a pulsed TWT

An electronic power conditioner (EPC) for a pulsed microwave transmitter tube is described, which operates in various switched modes of output pulse width and duty factor, while maintaining a low input current ripple and a high degree of output voltage stability. This has been achieved by applying a forward control signal to the error amplifier of the Collector regulator in a special phase relation to the microwave control pulses, and by a fast reacting control loop of the cathode-helix regulator, in conjunction with forward control of the input current limit. Recent performance tests confirm the very low level of the residual current- and voltage transients caused by mode switching. Test results are presented and discussed.