Series active power filter for current harmonic and load voltage compensation

A multi-function of series active power filter is presented to achieve current harmonic and load voltage regulation. Under the normal utility voltage condition, the series inverter is controlled to achieve current harmonic suppression so that the total harmonic distortion is reduced. If the abnormal utility voltage is detected at the load side, the series inverter is operated as a controlled voltage source to protect the sensitive loads against the voltage disturbances due to short-term abnormal voltage conditions. The reduced switch-count inverter is used in the single-phase system to compensate voltage disturbance for low power applications. The front-end diode rectifier is used to supply the necessary active power under the voltage sag condition. The adopted topology and control strategy are evaluated through several simulation studies.