Babak Mehdizadeh Gavgani, Department of Electrical Engineering, Seraj University, Tabriz, Iran.
The output voltage of a solar cell varies due to environmental conditions such as changes in temperature and solar radiation intensity which means that the output power of the photovoltaic (PV) arrays is not constant. The PV output power has a unique maximum power point in every operation conditions. In order to extract the highest efficiency of a solar cell and optimize the PV system performance, it is necessary to track maximum power of a PV cell (MPPT). This paper presents a comparative study of Sliding Mode Controller (SMC) and Incremental Conductance (INC) algorithm to track maximum power point of photovoltaic arrays. Both controllers maximize the output power of the PV system by adjusting the duty cycle of a DC/DC boost converter. The simulations under different environmental variations confirm the stability and the robustness of both controllers however it is shown that the SMC has a better performance and is fast in precise.
Index Terms— DC/DC boost converter, incremental conductance, maximum power point tracking, photovoltaic system, sliding mode controller.