Keywords: active power filters, shunt APF, DC-bus capacitor voltage, harmonics, reactive power compensation, total harmonic distortion, THD, performance evaluation, line current shaping, current control, simulation
Performance evaluation of different line current shaping controllers of shunt active power filters
This paper deals with the performance evaluation of three different control methods for line current shaping in single-phase system using shunt active power filter (APF). The first two methods are indirect current control based on source current sensing and the last one is a direct current control based on load current sensing. The method I is investigated with an aim to compensate only customer generated harmonics and reactive power to attribute the responsibilities of the utility and customer at the point of common coupling (PCC). The inventing feature of method I is its realisation without the use of source voltage signal. The methods II and III are presented with an objective to compensate customer as well as utility generated harmonics and reactive power. The detailed mathematical modelling of all three controllers is presented. The performance of these controllers is investigated for rapidly varying load under sinusoidal and non-sinusoidal source voltage conditions. The total harmonic distortion (THD), dc-bus voltage, settling time and complexity are considered as major indices for comparing the simulated responses. The simulation model of each control scheme is developed in MATLAB/Simulink environment and then co-simulated in TI TMS320F2812 digital signal processor as processor in loop (PIL).