ECE 590 I POWER & ENERGY SYSTEMS SEMINAR
WHEN: Monday, November 1, 2021, 3:00 – 3:50 p.m.
WHERE: 4070 ECEB and Zoom (contact Robin Smith for details)
SPEAKER: Elie Libbos, Electrical and Computer Engineering, UIUC
TITLE: "Inverter Design Considerations in a Variable-Pole Induction Motor in Electric Vehicles"
ABSTRACT: Induction machines (IMs) are an attractive magnet-free solution for electric vehicle (EV) drivetrains. While IMs are rugged, reliable, and inexpensive compared to permanent-magnet based motor alternatives, the attainment of the required EV torque/speed characteristics using a fixed-pole IM is a major challenge. Our proposed solution is a co-design of a variable-pole IM and its associated 18-phase drive to address the wide-speed-range requirements in EV applications. The proposed approach improves efficiency, power density and thermal management of IM drivetrains. This presentation discusses the drive design considerations for a variable-pole IM in EV applications. An experimental, toroidally wound IM driven by an 18-phase GaN converter is used to validate the proposed design. Our proposed drive is benchmarked against a conventional three-phase fixed-pole drive.
SPEAKER: Debranjan Mukherjee, Electrical and Computer Engineering, UIUC
TITLE: "A Reduced-switch Multilevel Rectifier"
ABSTRACT: In various applications, including industrial drives, renewable power generators, power factor correctors, the demand for high power – multi-MW – converters which are connected at medium voltage levels – 2.3, 3.3, 4.16 or 6.6 kV – in AC networks is increasing. In such cases, multilevel voltage source converters are preferrable over two-level converters, in light of their advantages of reduced device voltage rating, lower harmonic contents in the line-to-line voltages, lower dv/dt and, therefore, reduced EM interference. There are some applications, in which the active power flows from the AC side to the DC side. Examples of such applications are power supplies for telecommunications include aircraft, naval propulsion systems, X-ray, pumps and blowers requiring no regenerative braking and the machine-side converter for wind energy conversion systems. In such applications, reduced-switch non-regenerative rectifiers are deployed as they reduce circuit complexity and costs with enhanced power density and reliability. In this presentation, we identify the advantages/disadvantages of the existing multilevel rectifiers and propose a reduced-switch multilevel – five levels or more – rectifier topology. We also discuss the features of higher power density, improved efficiency and reliability, and reduced costs and complexity.
