Optimal Design of Anti-Resonance Third-Order Harmonic Filters for Power Systems Operating in Non-Sinusoidal Conditions

Power quality issues, especially power system harmonic distortion, are becoming potentially serious because of the widespread use of nonlinear loads, as well as renewables and power electronic-based equipment. Currently, power system harmonics management is not an additional option in power - electronic era. Even though 3
^rd
order harmonic filters were in operation many years ago, their design remains not straightforward. Hence, they could be inspected under different design objectives. In this work, a proposed optimal design of anti-resonance 3
^rd
order harmonic filters is presented, given that background voltage harmonic distortion of the utility and the injected current harmonic distortion of the industrial consumers (hybrid nonlinear and linear loads) present. The optimal solution is expressed based on the minimization of two objective functions - weighted driving point impedance and total cost with many nonlinear constraints of the filter and the system while considering series and parallel harmonic resonance damping metrics to quantify the filters' capability of resonance damping. Particle swarm optimization is chosen to find the optimal filter design for its success and fast convergence in solving constrained nonlinear harmonics management optimization problems. The results obtained show the excellent performance of the proposed filters.