Power Angle Control of a Unified Power Quality Conditioner in Railway Electrification System

This paper presents the load reactive power demand sharing strategy based on power angle control (PAC) method for the unified power quality conditioner (UPQC) in the railway electrification system. This work focuses on performance of reference signal generation for UPQC. Therefore, to clearly investigate its performance, the series active power filter (series APF) and shunt active power filter (shunt APF) are represented by ideal voltage sources and ideal current sources, respectively. The testing results by the processor-in-the-loop (PIL) technique on an eZdsp
^TM
F28335 board and the MATLAB/Simulink program confirm that the proposed strategy can share the balanced load reactive power compensations between the series APF and the shunt APF. The harmonic current mitigation, power factor correction, and voltage variations (sag/swell) compensation in the railway electrification system can also be achieved using the UPQC with the proposed strategy. The performance indices for the power quality improvement can also be kept within the IEEE Standard 519 and the IEEE Standard 141.