Digital control of MPPT structures for water pumping systems

This paper presents a development and implementation of a simple but efficient photovoltaic water pumping system. The system employs maximum power point tracker (MPPT), is composed of PV generator, DC-DC boost converter, DC-AC converter, induction motor and centrifugal pump. Two MPPT algorithms, constant voltage and short-current pulse methods will be modeled and implemented in dspace environment for practical evaluation. Each model is responsible for driving the dc-dc boost converter to track maximum power point (MPP) by instantaneous digitally control of duty ratio which respect different weather conditions. The effectiveness and higher efficiency of the proposed MPPT schemes is demonstrated experimentally under various operating conditions.