Comparison between various approaches without weighting factors with conventional MPTC for linear induction motors

Area of Science:

• Electrical Engineering
• Control Systems
• Power Electronics

Background:

• Model predictive control (MPC) is effective for linear induction motor (LIM) drives, offering direct switching and online optimization.
• Conventional MPC (MPC-Conv.) requires complex tuning of weighting factors for thrust and flux, while MPC-NAR lacks full-speed stability.
• Existing methods present challenges in design complexity and stable operation across the entire speed range.

Purpose of the Study:

• To propose novel MPC strategies for LIM drives that eliminate weighting factors.
• To introduce two MPC formulations utilizing a single cost function with hard constraints: MPC-Flux Constr. and MPC-Thrust Constr.
• To enhance control performance and reduce design complexity for LIM drives.

Main Methods:

• Development of two MPC strategies employing a single cost function with hard constraints to avoid weighting factors.
• Implementation of a hard flux boundary (MPC-Flux Constr.) in the first strategy.
• Application of a hard thrust boundary (MPC-Thrust Constr.) in the second strategy, focusing on flux-based control.
• Simulation analysis using a 3-kW arc induction motor under various operating conditions.

Main Results:

• The proposed MPC strategies significantly reduce cost-function complexity.
• MPC-Flux Constr. with a hard thrust constraint demonstrates superior performance compared to existing methods.
• Achieved faster speed regulation, reduced thrust ripple, and ensured stable operation across the full speed range.
• Demonstrated a reduced computational burden for the proposed strategies.

Conclusions:

• The developed MPC strategies effectively eliminate weighting factors for LIM drives through hard constraints.
• The flux-based MPC with a hard thrust constraint provides robust and efficient control performance.
• These novel approaches offer a simplified design and improved operational stability for LIM drives.