VOLTAGE CONVERTER AND ITS CONTROL PROCESS Russian patent published in 1999 - IPC

FIELD: electrical engineering and electronics. SUBSTANCE: converter has all its switching members implemented on single- operation switch and non-controlled diode connected in parallel opposition. Introduced in filter circuit of device that builds up two to power N stepped voltage, where N is a priori preset integer number greater than 1, in series starting from first-rank initial bridge circuit and in each of next n-rank circuits incorporating two to power n reactive sections, where n = 2,3...N-1, respectively, base bridge circuits with n+1-rank switches to replace mentioned sections. Method involves opening diagonal single-operation switches of ascending-rank filter after filter current crosses zero for first time upon output voltage polarity reversal at intervals exceeding cut-off time of single-operation side switches, opening single-operation side switches of descending-rank filter after filter current crosses zero for second time at intervals exceeding cut-off time of diagonal single- operation switches, and performing cyclic rearrangement of single- operation switches of equal-rank filter in opening sequence. Power current of single-operation switches whose time component at zero does not exceed maximum component of converter output current smoothly and easily crosses zero. EFFECT: reduced initial and final switching voltages across switching members, reduced phase shift of output current, improved stability of converter. 2 cl, 5 dwg