Maximum power point tracking of photovoltaic systems using simple interval type-2 fuzzy logic controller based on hill climbing algorithm

Abstract

Photovoltaic systems are generally operated in environments with rapidly changes in atmospheric conditions. Maximum Power Point Tracking system is required to keep the operation of photovoltaic at the maximum power point. In this research, a simple interval type-2 fuzzy logic controller is designed as maximum power point tracking system. Based on the hill climbing algorithm, the proposed interval type-2 fuzzy logic controller has two input variables and one output variable. The first input variable is the derivative of power versus voltage, while the second input is the change of the first one. The output variable is the rate of change in the duty cycle of DC-DC converter to control the voltage operation of photovoltaic. Two interval type-2 fuzzy membership functions are used to determine each input variables, while there are four fuzzy singletons in output variable. This simple interval type-2 fuzzy logic controller has only four rules as the maximum power point tracking strategies. Simulation results show that the proposed simple interval type-2 fuzzy logic controller provides fast dynamic response in the rapid change of atmospheric conditions while keeping the operation of photovoltaic at its maximum power point.