Obtaining steady high-voltage direct current from a thermionic rectifier without a filter

The usual polyphase high-voltage rectifier produces a potential essentially constant out having superposed on it a “ripple” or alternating component whose amplitude on each side of the mean is from five to seven per cent of the total d-c. voltage. Condensers and reactors are used to filter the ripple out. The paper describes a special type of a-c. generator which will give the proper low-voltage wave form for rectification as a more nearly smooth direct potential. A method of manually or automatically varying the low-voltage wave form according to load demands is provided so as to keep the rectified potential steady, thus avoiding the necessity for the filter which in sets for 100,000 volts or more would be quite expensive and troublesome.