The study is based around a 26kW induction motor and IGBT inverter drive, which is typical of the technology used to power a small urban vehicle. The method of modulation employed will influence the harmonic content of the supply to the motor, the level of parasitic harmonic loss in the machine and the switching losses of the power semiconductors.
The stator phases Induction machine thesis a magnetic field in the air gap rotating at the speed of the stator frequency 1. The control of the supply voltage magnitude necessitates the use of some form of modulation on the output of the power converter. A typical asynchronous motor is shown in Figure General equations of AC Motors The asynchronous or AC induction motor is represented by a stator and a concentric rotor with three-phase windings and a narrow airgap between the smooth surfaces of the rotor and the stator.
If the rotor revolved at the same frequency as the stator, then the rotor field would be in phase with the stator field and no induction would be possible. There is no current supply needed from outside the rotor to create a magnetic field in the rotor.
The connection between the stator and the rotor is made by the flux, which means there is no mechanical connection between them apart from the bearings. A particular consideration is that, for the majority of the time, the electric drive-train will be operating at part load.
Sinusoidal Current density distribution Presume a symmetrical three-phase windings system in the machine. It is shown that compared to the established method of constant flux and fixed inverter switching frequency control, a significant reduction in the traction system loss can be achieved.
Only the stator windings are fed by a voltage or current source inverter. The thesis investigates the operation of induction motor based electric traction drive-trains, with a view to minimising the system loss over typical driving cycles.
Because of its outstanding robustness among all AC Motors, as can be seen in the Figure Classification of electric motors The following section will briefly describe this motor with the purpose of a deeper insight into its behavior later on.
As a consequence of the forces created by these two fields, the rotor starts rotating in the direction of the stator field but at a slower speed. This is the reason why this motor is so robust and inexpensive. Machine equations in a natural co-ordinate system The voltage equations of the stator are the following: A theoretical study supported by experimental work on a DSP controlled drive is presented and used to determine the most appropriate modulation strategy at a given operating point to achieve an optimal balance between the motor copper, iron and harmonic loss and inverter switching and conduction loss.
Cross section of an Induction Motor 7. A potential advantage of an induction motor based drive-train is the ability to vary the level of excitation field in the motor, and therefore the balance of iron and copper loss.
Considerable improvements in vehicle range are possible, however, by ensuring the most effective use of this limited energy resource through the minimisation of the losses in the electric drive-train, i.
PhD thesis, University of Sheffield. A metal ring at the ends resulting in a short circuit connects the wires along the rotor axis.
Some different modulation schemes involve varying amounts of computational overhead in a DSP, the implementation of candidate modulation and control schemes has also been investigated to ensure the defined scheme is practically realisable. An asynchronous motor The changing field induces a current in the cage wires, which then results in the formation of a second magnetic field around the rotor wires.
Further, the experimental application of this motor type has growing significance.
Energy efficient PWM induction machine drives for electric vehicles. There are several ways to control an induction motor in torque, speed or position, which can be categorized into two groups:Master Thesis MODELING AND SIMULATION OF A SERIES HYBRID ELECTRIC VEHICLE PROPULSION SYSTEM Induction machine thesis Santiago Muñoz Aguilar Advisers: Enric Fossas Colet a novel conﬁguration which is composed by a synchronous mach ine and an induction machine is also presented.
As said before, the second problem consist in. Brijesh Upadhaya Design of Torque Exciter for Induction Machine School of Electrical Engineering Thesis submitted for examination for the degree of Master of.
Induction Motor (DSLIM) that is proposed for use as an Electromagnetic Aircraft Launch System (EMALS) aboard the CVN-2 1. electric energy that the machine consumes.
This thesis is meant to propose a maximum possible efficiency for a DSLIM in this type of role. Thesis Supervisor: James L. Kirtley Jr. An understanding of the dynamics of this type of induction machine is needed to improve the current state of the art in running power system dynamic studies. In this thesis, a novel approach of modeling an exact fourth-order model of a.
state estimation techniques for speed sensorless field oriented control of induction motors a thesis submitted to the graduate school of natural and applied sciences.
This Bachelor thesis is focused on induction motor protection problems. Basic information concerning of induction machines, its protection and diagnostic methods are included.
In the end invention of the induction machine which has two fathers: Galileo Ferraris () and Nicola.Download