A Simplified Control Technique for a Dual Unified Power Quality Conditioner

This paper presents a simplified control technique for a dual three-phase topology of a unified power quality conditioner. The Dual UPQC is composed of two active filters, a series active filter and a shunt active filter (parallel active filter), used to eliminate harmonics and unbalances. Different from a conventional UPQC, the Dual UPQC has the series filter controlled as a sinusoidal current source and the shunt filter controlled as a sinusoidal voltage source. Therefore, the pulse width modulation (PWM) controls of the Dual UPQC deal with a well-known frequency spectrum, since it is controlled using voltage and current sinusoidal references, different from the conventional UPQC that is controlled using no sinusoidal references. In this paper, the proposed design control, power flow analysis, and experimental results of the developed prototype are presented.