FIELD: electrical equipment.
SUBSTANCE: present invention relates to electric frequency converters of high-power electric drives with high output voltage quality parameters and can be used as torque, speed or power control device on the shaft of the actuating electric motor of virtually any AC electric drive. Delivered targets are achieved by the fact that the cascade frequency converter comprises a power matching multi-winding transformer, which secondary windings are connected by star and contain output of zero point. Single-phase frequency converters are made on two completely controlled power switches. Advantages of proposed cascade frequency converter include simple circuit design of main component—single-phase frequency converter.
EFFECT: technical result of invention is significant reduction of number of fully controlled semiconductor power switches of power circuit of cascade frequency converter, thereby increasing efficiency, operating reliability, operating characteristics of the cascade frequency converter, and also significantly simplifies control system and cooling system of power modules of elementary cells of cascade frequency converter.
4 cl, 3 dwg
