FREQUENCY CONVERTER CONTROL PROCESS Russian patent published in 2000 - IPC

FIELD: converter engineering; control systems for ozonizers. SUBSTANCE: control process for frequency converter that has rectifier with capacitive filter at output and push-pull inverter built around fully controlled reverse-shunted diodes, connected to rectifier output leads, and operating into inductive load includes generation of control pulses and their alternate supply to diode shaping forward and reverse current half-waves across load. In the process, instant values of currents are measured across diagonally opposite ac terminals of inverter, moment when current measured across diagonally opposite terminals of inverter equals zero is determined, control pulse is applied, and next diodes are turned on not earlier than at instant when current measured across diagonally opposite ac terminals of inverter equals zero; then rectangular pulses are generated their cycle being 0.5T, where T is cycle of output ac current; trailing edge of pulses depends on diode turn-off moment; output ac current is controlled by regulating moment of control pulse supply and diode turn-on in the range between moment when current measured across diagonally opposite ac terminals of inverter equals zero to half-cycle of ac output current. EFFECT: improved reliability of frequency converter. 2 dwg