Hybrid automaton-fuzzy control of single phase dual buck half bridge shunt active power filter for shoot through elimination and power quality improvement

This paper addresses the problem of controlling a single phase shunt active power filter (SAPF) in presence of nonlinear loads. The considered SAPF is based on a Dual Buck Half Bridge converter (DBHB), which has the ability to eliminate the shoot-through problem arising in the conventional inverter circuit. The aim is to design a controller that is able to achieve the following three control objectives: (i) simple and indirect estimation of harmonic components, (ii) compensating for the harmonic and reactive currents generated by the nonlinear load for assuring a satisfactory power factor correction (PFC) in the grid side, (iii) regulating the DC capacitor voltage of the DBHB converter. In order to meet these control objectives, a new controller based on multi-loop structure is proposed. In the inner loop, a hybrid automaton representation of the DBHB-SAPF is used for the purpose of designing an appropriate control law so that to ensure a unity power factor. In the outer loop, a fuzzy logic controller is developed to guarantee a tight regulation of the converter DC voltage to a desired value. The effectiveness of the proposed controller is verified and validated by numerical simulation using MATLAB/ Simulink environment. From the obtained results, the designed controller shows significant performance in terms of robustness and tracking compared to the standard strategy based on PI regulator.

Automated summary

This paper introduces a new controller design based on a multi-loop structure to address the problem of controlling a single phase shunt active power filter (SAPF) in presence of nonlinear loads. The designed controller shows significant performance in terms of robustness and tracking compared to the standard strategy based on PI regulator.