SINGLEEPHASE REACTIVE POWER CONVERTER

摘要

PURPOSE:To enable detection of a reactive power with small errors even for an imbalance three-phase power system and a frequency fluctuation system by multiplying the volume of electricity corresponding to the current and voltage of a power system phased in a prescribed manner and by removing an unrequired component of frequency with a filter. CONSTITUTION:The current and voltage of a power system are converted into prescribed electric volumes by input converting circuits 1 and 2, while they are advanced or delayed in shifting respectively by phase angles of theta, 90-theta degrees by phasers 3 and 4. And when the outputs of the phase shifters 3 and 4 are processed for multiplication in a multiplying circuit 5, they turn to be a DC component proportional to the volume of the reactive power and a higher harmonic component which is double the volume of inputted electricity. When this unnecessary higher harmonic component is removed by LPF 6, the reactive power with small errors also for an imbalance three-phase power system and a system wherein the frequency fluctuates is detected and thus the single-phase reactive power converter which can continue operation even when the rated frequency is changed.