An optimal strategy with convex-concave constraints for power factor correction and harmonic compensation under different voltages

This paper presents an optimal control strategy for load current compensation under different PCC voltages, including the ideal, distorted and unbalanced situations. This optimal strategy compromises the conflicting targets in the source currents, leading to a non-convex problem with convex quadratic cost function and non-convex quadratic constraints. To solve this non-convex quadratic constraints quadratic programming(QCQP) problem, by writing the constraints as a difference of two convex quadratic functions(DC), this paper introduces the sequential convex programming(SCP) algorithm based on the iterative method of the DC programming, in which the non-convex parts in the constraints are sequentially linearized. The fast convergence in a few iterations is illustrated to demonstrate the performance of the algorithm. The simulation in MATLAB of a three-phase system feeding a nonlinear load has shown the effectiveness and feasibility of the proposed compensation strategy.