BIAS MAGNETISM DETECTION DEVICE OF AC POWER SYSTEM AND BIAS MAGNETISM RESTRAINT

摘要

PROBLEM TO BE SOLVED: To provide a bias magnetism detection device capable of detecting an excitation current included in an output current from a system interconnection electric power converter which is directly interconnected to an AC power system without being interposed by an interconnection transformer and capable of extracting DC components requiring no high-accuracy current detector with a wide current detection range, and to provide a bias magnetism restraint.SOLUTION: An interconnection electric power converter is connected to an AC power system directly or being interposed by an interconnection transformer, and to the output of the interconnection electric power converter, a reactive element is connected. The bias magnetism detection device includes: a current detector for detecting a current flowing on the reactive element; and a DC current extraction circuit for extracting a DC current component from the current detected by the current detector.SELECTED DRAWING: Figure 1