Fuzzy Control of a High-Performance Boost Converter in Discontinuous Conduction Mode and its Application to a Photovoltaic Pumping System

In this work, a fuzzy voltage controller design of a 1 kW high-gain, high-efficiency direct current converter operating in discontinuous conduction mode is developed. In this condition, the design of a conventional controller is more challenging. This converter is part of an autonomous photovoltaic pumping system without batteries consisting of four photovoltaic modules, a variable frequency inverter and an induction motor coupled to a pump. The boost converter is responsible for the voltage elevation of photovoltaic modules to a 311V direct current bus, which must not have oscillations for a good operation of an algorithm to track the maximum power point of the modules. The fuzzy controller was implemented in a digital signal processor device to control the boost converter, producing a response with an overshoot of 5.78%, settling time of 3.8s and zero error in steady state.