JPS6443065A - Power converter - Google Patents

Abstract

PURPOSE:To prevent troubles in overcurrent and etc., by controlling a phase control circuit by power phase given to a power conversion element and phase rotation. CONSTITUTION:A power converter is constituted of a power transformer 1, a breaker 2, AC machines 4-5, a current detector 6, a voltage phase detector 13 of power source, comparators 14-16, a phase rotation detector 30 of power source, a switch 31, a PLL circuit 17, a power control circuit 19, a phase control circuit 18, a switch 32 and a timer circuit 34. And, the phase rotation is detected by the phase rotation detector 30 through each output signal (e1) and (e2) of the comparators 14-15, and the switch 31 is turned off and etc., to input to the PLL circuit 17 and to synchronize with the power phase. And, in consideration of a malfunction in the rise-up time of power and in the time of disconnection of the breaker 2, an operation starting command is given to the phase rotation detector 30 through an auxiliary contact 33 of the breaker 2 and an output signal (e3) of the timer circuit 34. Accordingly, the confirmation of the phase and the phase rotation in the time of power connection is not required.