Design and Implementation of Double PI Controller in Three Level DC-DC Converter (TLDDC) for PMSG Wind Turbine

Abstract

This paper discusses a converter with a new strategy as a solution for converting 3-phase AC electrical energy from a wind turbine permanent magnet synchronous generator (PMSG) into DC electricity with more stable power due to the increasing demand for DC electrical energy. Three level dc-dc converter (TLDDC) was chosen because it can convert higher DC voltage and current compared to conventional converters. The problem arises because the TLDDC is operated to convert the power output of the wind turbine PMSG in an open loop system. The problem is that the converter cannot adjust the voltage and current according to the load requirements. Therefore, open-loop systems must be converted to closed-loop and usually use only single control. A single control is ineffective because it can only control voltage or current. This control cannot control voltage and current simultaneously. When the load is changed, the output voltage or current changes. From these problems, this study proposes a new strategy double control system that utilizes the PI dual control strategy for voltage and current. Based on the simulation and hardware implementation, this double PI control performance has been tested and measured with good results. The results of this study indicate a stable voltage at 48 Volt DC and a stable TLDDC output current according to load requirements with a pure DC output signal and lower ripple even though the speed of the wind turbine PMSG is always changing.