Comparative study of reference currents and DC bus voltage control for Three-Phase Four-Wire Four-Leg SAPF to compensate harmonics and reactive power with 3D SVM

A new balancing three level three dimensional space vector modulation strategy for three level neutral point clamped four leg inverter based shunt active power filter controlling by nonlinear back stepping controllers

“…Recently, about the world the industrial and domestic equipment are progressively use the single and three phase unbalanced non-linear loads, such as rectifiers, power supplies and speed drivers, include nonlinear dynamics that entail the generation in four wire distribution networks the current harmonics, zero sequence current, and consumption of reactive power, these harmonics, zero sequence current, and reactive power causing harmful effects, such as the distortion of loads and waveform of line voltages, boosted ageing of loads and disturbing the other electronic equipments connected to the four wire distribution networks [1][2][3][4].…”

“…The modern filtering solutions to eliminate these harmonics and zero sequence current, and to improve the quality of electric power are, the four leg shunt active power filters (SAPFs), they can extensively studied and effectively solution for improve the mainly power factor by the elimination of harmonic currents and zero sequence current, and the compensation of reactive power into the point of common coupling (PCC) in three phase four wire electrical networks [3,[5][6][7]. The most powerful converters used in four leg shunt active power filter have been the two-level four leg inverters.…”

“…Several others researchers described the effects of reference currents generation theories on the performance of SAPFs [3,17]. For improvement the SAPF performances, in [35] have explicated the Synchronous Reference Frame theory (SRF) for reference currents generation based SAPF.…”

“…The Synchronous Reference Frame theory is analyzed for three leg two level SAPF, Shunt Hybrid Active Power Filter (SHAPF) [35,37], and the DSTATCOM [38,39], and in four leg two level SAPF and DSTATCOM [3,14]. This concept has been extended by simulation studies to three-level NPC three and four leg SAPFs [30,40] using the same loads model presented in [3]. The Synchronous Reference Frame theory is extracted the reference harmonic currents directly after Park Transformation of distorted loads currents using low pass filter (LPF).…”

“…Therefore, the dynamic performance of linear PI regulators uses in dc bus voltage capacitors and reference currents regulation are not robustness and not stabilization due to loads unbalanced and parameter variations. The Nonlinear Back Stepping Controller (NBSC) (BSRs) possibly will be used for improving the dynamics of linear PI regulators to have increase the robustness, the stabilization, gives good regulation on the dc bus voltage and the SAPF injected currents by the elimination of overshoot and undershoot in the dc bus voltage capacitors and the elimination of the error between the SAPF injected currents and there references [3]. The Nonlinear Back Stepping Controller (NBSC) is a systematic and flexible technique, newly developed and can be effectively used to linearize a nonlinear system in the presence of uncertainties.…”