Fuzzy logic supervisory controller for multi-input non-isolated DC to DC converter connected to DC grid

Abstract

Multi-Input DC-DC Converter (MIDC) which integrates different renewable sources is an evolving technology. Researches in this field gave several topologies and configurations of Multi-Input DC to DC converters, for integrating multiple sources. In this work, a topology is identified first and a controller with power management is explored. A non-isolated series MIDC with three input sources is selected to inject power into the DC grid. This Unidirectional topology with less no of switches is selected to integrate renewable sources such as Photovoltaic Cells, Wind, Fuel Cells etc. to the grid. The topology acts like a boost converter to integrate low voltage sources to high voltage grid. Power management and control of MIDC, connected to grid is a challenging task, as viable techniques are still not explored. Fuzzy Logic Controller is proposed as a supervisory control for Power Management. Fuzzy Logic Supervisory control (FLSC) decides the quantum of power, which each source has to supply, depending upon the availability of power. Controller used for voltage and current control is simple PI controller. The closed loop simulation studies are done using MATLAB/SIMULINK and experimental results obtained using OPAL-RT is used to validate the identified configuration for power management. The main advantages of this converter are less component count, compact structure, and efficient energy utilization.