High performance MPPT control of photovoltaic using VSSIC method

Abstract

This paper proposes a variable step size incremental conductance(VSSIC) method for the maximum power point tracking(MPPT) control of a photovoltaic. The conventional perturbation & observation(PO) and IC MPPT control algorithm generally uses fixed step size. A small fixed step size will cause the tracking speed to decrease and tracking accuracy of the MPP will decrease due to large fixed step size. Therefore, this paper proposes the VSSIC MPPT algorithm that adjusts automatically step size according to operating conditions. To improve tracking speed and accuracy, when operating point is far from maximum power point(MPP), step size uses maximum value and when operating point is near from MPP, step size uses variable step size that adjust according to slope of curve. The validity of MPPT algorithm proposed in this paper proves through compare with conventional IC MPPT algorithm.