High-precision speed control of induction motors using a multi-pulse voltage source converter and advanced observer-based strategies

Abstract

This paper presents a speed motor control using a precise Electric Motor Drive System (EMDS) utilizing an 84-pulse Voltage Source Converter (VSC). The development of the VSC signal requires two critical parameters: Vmodule, representing the combined amplitude of the 3-phase signals, and a variable frequency adjusted via a Phase-Locked Loop (PLL) within each sample cycle. To estimate the non-measurable variables (λαr, λβr and TL), sliding mode, asymptotic, and Luenberger observers are employed and compared among themselves. The control algorithm is based on sliding mode with an equivalent control strategy, ensuring robust performance under various operating conditions. This control algorithm transforms the plant to be controlled to the non-linear block control form by using error-tracking dynamics. This is to obtain the sliding manifold and to apply the equivalent control strategy. The effectiveness of the proposed system is validated through a set of simulations conducted in Matlab/Simulink, demonstrating its capability to achieve high precision in motor drive applications.

Keywords

• Sliding mode observer
• Asymptotic observer
• Luenberger observer
• VSC
• EMDS