در عمق تجزیه و تحلیل کراس-جفت شدن در عملکرد موتور القایی با کارایی بالا

High-performance field oriented control (FOC) of induction motors (IMs) relies on the accurate control of their electrical dynamics. In particular, perfect decoupling control of the stator currents should be ideally achieved for a FOC scheme to be efficient. However, the decoupling effectiveness afforded by most stator currents controllers may be influenced not only by the parameters and the operating condition, but also by the specific controller structure and the adopted coordinate system. A measure to assess decoupling effectiveness is non-existent in the IM control literature. To bridge this gap, an in-depth analysis of the cross-coupling inherent characteristics of the electrical subsystem of IMs under different well-known control structures is presented in this paper. Specifically, four control strategies previously studied and experimentally validated in the literature are critically assessed in this work: (1) stationary frame proportional-integral (PI) control, (2) synchronous frame PI control, (3) synchronous frame PI control with decoupling networks, and (4) improved stationary frame diagonal control. The decoupling capabilities of controllers in stationary and synchronous coordinates are examined, with a detailed insight on the role of decoupling methods. The analysis is performed in the frequency domain under the framework of individual channel analysis and design (ICAD). By application of ICAD, the decoupling effectiveness of FOC schemes is clearly exposed and quantified, with an assessment of the effects of parametric uncertainty being carried out for completeness. The effect of the inverter dynamics over cross-coupling is also treated using digital simulations. The results are useful to determine the conditions in which each control strategy has either advantages or disadvantages. Additionally, it is possible to determine the effect of several operating parameters over the stator currents cross-coupling such as nominal flux and torque levels.