FREQUENCY CONVERTER CONTROL PROCESS Russian patent published in 2000 - IPC

FIELD: converter engineering; controlling transistorized frequency converters. SUBSTANCE: controlling frequency converter that has rectifier built around diodes, capacitive filter, and push-pull transistor inverter each of whose transistors being shorted out by switching capacitor and opposing diode operating into inductive load involves generation of control pulses and their alternate supply to transistors shaping forward and reverse current half-waves across load. In the process, voltage level is set, instant voltage value across transistor that has stopped conducting is measured and compared with preset level, control pulses are applied, and next transistor is driven in conduction at moment when instant voltage and preset level are equal. Two rectangular-pulse trains of 0.5T length are shaped, where T is ac output current cycle; transistor turn-on moments depend on leading edges of pulses. Voltage level is set during converter starting and its value makes up 0.4-0.5 of rectifier output voltage level. EFFECT: improved operating reliability of frequency converter. 2 dwg