Date of Award
5-16-2024
Publication Type
Dissertation
Degree Name
Ph.D.
Department
Electrical and Computer Engineering
Supervisor
Narayan Kar
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Abstract
In modern industry, particularly within the realm of transportation electrification, induction machines (IMs) and permanent magnet synchronous motors (PMSMs) are assuming increasingly pivotal roles. As electric machine technology continues to advance, the significance of analyzing noise and vibration (NV) is on the rise. Comprehensive NV analysis not only ensures optimal performance and efficiency of traction electric machines in electric vehicles but also guarantees passenger safety and regulatory compliance. Moreover, prioritizing NV analysis enhances customer satisfaction and market competitiveness by delivering a superior driving experience and meeting stringent noise and vibration standards in the evolving electric vehicle market. This thesis initiates an in-depth exploration of NV modeling and analysis applicable to both IMs and PMSMs. Key aspects of NV analysis include electromagnetic force calculation, modal analysis, and the synthesis of NV through multi-physics models. Thorough investigations are carried out on electromagnetic force calculation, modal analysis, and NV synthesis. The findings from this comprehensive analysis contribute to a nuanced comprehension of the complex interactions among electromagnetic forces, structural dynamics, and acoustic radiation. This insight offers valuable guidance for the optimization and enhancement of electric machine designs. Moreover, this study delves into the influence of both stator and rotor geometry on vibrations. The initial stage entails the selection of an Interior permanent magnet synchronous motor for a primary investigation into how stator geometry impacts vibrations through sensitivity analysis. Subsequently, the research expands its focus to scrutinize the impact of rotor type on vibrations in an induction machine. The analysis further explores the sensitivity of the main stator geometry, investigating various rotor slot types in an induction machine to formulate methodologies aimed at enhancing NV performance. Addressing the common open-phase fault in motor drives, the intrinsic reliability and fault-tolerant capabilities of six-phase IPMSMs are attributed to their multiphase configuration. The stator currents during the open-phase fault are conceptualized as a combination of positive and negative sequence currents, projecting only the positive sequence components into the torque-producing subspace and transforming negative sequence components into the harmonic subspace. By applying conventional and modified vector space decomposition (VSD) to the positive and negative sequence components within the dual three-phase system, the machine can deliver the desired torque and power even under such faults. The utilization of conventional proportional-integral (PI) current regulators facilitates control over the dc components of positive and negative sequence currents under the open-phase fault. However, there is a need to explore the vibroacoustic characteristics of the IPMSM during faulty operation with the FTC methodology. This is accomplished by conducting simulation and experiment-based NV analysis on a six-phase IPMSM with a single open-phase fault, utilizing the proposed negative sequence current-compensated FTC mode. Comparing the NV performance in healthy and controlled faulty modes, employing FTC led to remarkable reductions in both maximum deformation and sound pressure level (SPL) during faulty operation. Specifically, after applying FTC, the maximum deformation under the faulty operation decreased by 12.9% compared to the scenario without FTC, highlighting the significant structural stress mitigation achieved. Furthermore, the SPL of the machine under the faulty operation with FTC decreased by 16.9% compared to the one without FTC, demonstrating substantial noise reduction. Importantly, our experiments confirmed these findings, showing a strong correlation with the simulation results and providing robust validation of the efficacy of the proposed FTC methodology. These results underscore the pivotal role of FTC in successfully mitigating noise and vibration issues in electric vehicle propulsion systems, thereby enhancing their reliability and safety.
Recommended Citation
Song, Pengzhao, "Noise and Vibration Analysis of Traction Electric Machine Under Open-circuit Fault Operation" (2024). Electronic Theses and Dissertations. 9411.
https://scholar.uwindsor.ca/etd/9411