Processor-in-the-Loop Implementation Using STM32F4 of PI Controller-Based Direct Power Control for Wind Energy Conversion Systems
Mourad Yessef, Yassine Seghrouchni, Hatim Ameziane, Badre Bossoufi, Ahmed Lagrioui
Abstract
This paper presents a control method for regulating the active and reactive powers of a Doubly Fed Induction Generator (DFIG) in wind energy applications. The proposed strategy is based on a Direct Power Control (DPC) technique enhanced with Proportional Integral (PI) controllers. The DPC PI approach effectively addresses the well-known limitations of conventional DPC, such as variable switching frequency, significant current and power fluctuations, and reliance on hysteresis comparators and switching tables. By replacing these components with PI controllers and incorporating a Pulse Width Modulation (PWM) scheme, the system achieves a fixed switching frequency and improved power quality. The control system was initially designed and evaluated in MATLAB/Simulink under various wind conditions to verify its operational accuracy. Following simulation, the control algorithm was discretized and implemented on the STM32F4 microcontroller, which is an economical and efficient embedded platform suitable for real-time power applications. Processor in the Loop (PIL) testing confirmed the controller’s effectiveness under dynamic conditions. The DPC PI controller demonstrated precise tracking of active and reactive power references, characterized by fast response times, minimal overshoot, and stable steady-state behavior. The Total Harmonic Distortion (THD) of the stator current was measured at 0.20%, which is well below the 5% threshold set by the IEEE 519 standard, confirming enhanced power quality. These results validate the reliability and feasibility of deploying the DPC PI method on the STM32F4 microcontroller. Its real-time performance, compliance with international standards, and cost-effectiveness make it a strong candidate for integration into commercial wind farms in Morocco and in other regions.