Examenspresentation av Binaya Adhikari & Oskar Blom

Conducted in collaboration with Volvo Cars under the supervision of Torbjörn Thiringer and Joachim Härsjö

Opponent: Adam Passachin & Hadi Kenaan

Abstract
As the world is transitioning from fossil fuel to clean and sustainable energy system, there has been a rise of electric vehicles sold around the world. Cost is a critical aspect in the selection of electric motors, and induction machines have an advantage in this regard as compared to PMSM. The absence of permanent magnets, which are expensive and complicated to manufacture, reduces the overall cost of the induction machine. Furthermore, the design of induction machines is simpler and more robust, making them more reliable and less prone to failure compared to PMSM.A lot of analysis have been performed with IM with sinusoidal feeding but very less has been done with PWM feeding due to the complexities involved.

This thesis compares the performance of induction motor when supplied with purely sinusoidal input and PWM on the basis of important motor characteristics such as tooth forces, torque ripple and losses. A minimum loss control algorithm is employed based on inverse gamma model of IM where core losses are modelled as the losses in the equivalent core resistance. One of the complexities with PWM implementation is the long computational time. This issue was addressed in this thesis with a strategic simulation sequence and few selected operating points were analysed to understand the behaviour of the induction machine. The induction machine was modelled in Finite Element Method (FEM) software called ANSYS Maxwell.

Welcome!

Oskar, Binaya, Joachim and Torbjörn