Optimal capacitor placement in harmonic distribution systems for voltage regulation and loss reduction with PSO

The nonlinear portion of the electrical loads has increased significantly in recent years. Harmonic currents injected by these loads into the distribution systems should be considered when solving the capacitor placement problem in order to assure that the optimal solution does not result in excessive harmonic distortion or resonant conditions. This paper presents a binary-PSO approach for placement of the capacitors in a harmonics-polluted distribution system. The binary- PSO is integrated with a harmonic power flow algorithm. In this problem objective function is the total cost of the system power losses, cost of the capacitors placement and additional penalty terms.Constraints in this optimization procedure are the rms voltage and the voltage total harmonic distortion (THDv), as well as available capacitor units to be placed at each bus. Sensitivity analysis is used to find the candidate buses for capacitor locations. Proposed methods are tested on the 9 and 13 buses harmonic distribution systems. Numerical results show that the proposed method advantageous results for the capacitor placement problem.