Abstract: By using a hill climbing technique, the input energy to the electrostatic precipitator electrodes is automatically increased until the electrode potential decreases. In response to the electrode potential decrease, the input energy is decreased. The electrode potential is controlled by an automatic voltage controller including an electrode potential sense circuit. The controller includes a digital store for increasing the count of the store and means responsive to the count in the store provide an output signal related to the count and means responsive to the signal from the electrode potential sensing circuit which is indicative of a fall in the electrode potential is used to reduce the count in the store. The count in the store is converted into an analog voltage used to control the duty cycle of thyristers and thus the precipitator electrode potential.

Abstract: A circuit for controlling the rectifier circuit in an electrostatic dust precipitator, the circuit being an oscillator circuit utilising a pair of alternately conducting transistors and a timing circuit controlling conduction of one of the transistors, the other transistor controlling the circuit output.