SINGLE PHASE ACTIVE FILTER FOR COMPUTER SERVER

摘要

A single phase active filter for computer server is provided to prevent contamination of a supply voltage of a server due to an inverter switching voltage ripple by installing an L-C-L filter at an output terminal of an inverter. A first voltage detector(4) receives a supply voltage of a server. A first current detector(5) receives load current of the server. A second current detector(6) receives current of a filter. A second voltage detector(11) receives a voltage of a DC capacitor(10). An AD converter(14) converts output signals of the voltage detectors and the current detectors to digital signals. A control unit includes a digital processor for calculating compensation values by using the digital signals and a digital output part for converting the compensated values to pulses. A gate driver supplies a signal from the digital output part to an inverter. The inverter receives the signal of the gate driver and outputs the compensated voltage to an L-C-L filter(8). The L-C-L filter converts the compensated voltage to the compensated current.