DC mains backup power system for frequency-controlled electric drive

This paper discusses the problems concerning design of a backup power supply system used for a frequency regulated AC electric drive. The one, in turn, is used in a circulating pump of a stand-alone object fed by DC mains. The backup power supply is based on a battery or an electromechanical generator. The topology and main characteristics of a bidirectional DC voltage regulator with galvanic isolation are considered. The control system structure is also described. Stability of operation at constant power mode of the converter is analyzed. Dynamic correction algorithm is proposed.