FREQUENCY CONVERTER Russian patent published in 2021 - IPC H02M5/40 

FIELD: electrical engineering; power electronics.

SUBSTANCE: invention relates to the field of electrical engineering and power electronics, in particular to static frequency converters with double conversion of electrical energy. The invention makes it possible to increase the reliability, simplify the manufacture, installation and operation, reduce the weight, dimensions and cost of the frequency converter, as well as automate the process of charging the storage capacitor. In addition, the proposed circuit of the frequency converter makes it possible to supply the control system through the newly introduced power supply unit from the buses of the DC link of the frequency converter, regardless of the presence of voltage in the supply network. The frequency converter contains a series-connected current-limiting charging resistor and a fuse that are connected in parallel to one of the thyristors of a semi-controlled voltage rectifier, as well as a power supply unit made in the form of an electric DC-to-DC converter and powered by a storage capacitor of the DC link of the frequency converter. The proposed circuit of the frequency converter has sufficient universality; it can be used to build frequency converters in a wide range of capacities.

EFFECT: improved minimum number of components of the frequency converter, the performance characteristics, and the process of pre-start diagnostics and charging of the storage capacitor of the two-link frequency converter is automated.

3 cl, 4 dwg