Model predictive control for quad active bridge DC-DC converter for more electric aircraft applications

Area of Science:

• Electrical Engineering
• Power Electronics
• Control Systems

Background:

• Quad-active bridge (QAB) converters offer advantages like galvanic isolation and shared magnetics for multi-port applications.
• Traditional controllers face challenges with QAB converters due to complexity, limited dynamic performance, and port coupling.
• Voltage overshoot/undershoot and slow response under load changes are common issues with existing QAB control methods.

Purpose of the Study:

• To develop an advanced control strategy for quad-active bridge converters.
• To address the limitations of traditional controllers in terms of dynamic response and steady-state errors.
• To enhance the performance and robustness of QAB converters across various operating conditions.

Main Methods:

• Implementation of a moving discretized control set-model predictive control (MDCS-MPC) strategy.
• Utilizing a converter model to predict phase shift values for enhanced dynamic performance.
• Incorporating an adaptive step for reduced computational load and faster transitions.

Main Results:

• The MDCS-MPC strategy demonstrated superior dynamic response and robustness in simulations and Hardware-in-the-Loop (HIL) experiments.
• Elimination of steady-state errors in control variables was achieved.
• Significantly reduced computational requirements were observed due to the adaptive step implementation.
• Fast voltage dynamic response with no significant overshoot or undershoot was confirmed.

Conclusions:

• The developed MDCS-MPC strategy effectively addresses the control challenges in quad-active bridge converters.
• The strategy provides a robust and computationally efficient solution for multi-port power applications.
• Experimental and simulation results validate the superior performance of the MDCS-MPC approach for QAB converters.