Reactive-power compensator for compensating a reactive-current component in an alternating-voltage system

摘要

A reactive-power compensator for compensating a reactive current component in an alternating-voltage system, including a reactive- current converter formed by forced-commutation current converter rectifiers arranged in a current converter bridge circuit, and a smoothing choke used as a termination at the direct-current side of the bridge circuit. The compensator attains constant compensation of both inductive and capactive reactive-current components with clearly reduced system reaction by driving the rectifiers such that the bridge circuit accepts at its input a compensation current in the form of approximately rectangular current pulses having a pulse frequency greater than that of the alternating voltage system. The polarity and width of these current pulses are modulated in accordance with a sine function so that the compensation current is identical in frequency and amplitude with respect to the reactive current component at the system voltage input, but shifted in phase by 180.