No description available.

Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 32-33).

Inaug.-diss.--Greifswald. / Lebenslauf.

M.Ing. (Electrical & Electronic Engineering) / In recent years, there has been a renewed interest in the synchronous reluctance machine, because it holds so many promises according to the mathematics. In the past very little research has been done in this field, due to the problems of controlling the machine and the necessary technology had not yet- been developed. When the machine is running synchronously, it can be very accurately controlled and is therefore suited for applications in the paper or textile industry. In this dissertation the possibility of accurately controlling the machine without the use of a position/speed sensor on the rotor will be investigated.

The analyses presented in this thesis are based on a consideration of induction effects below transmission lines and the hazards as presented to the public. The rapid increase of transmission voltages has caused a great deal of concern among utilities about these hazards. The induction effects are a function of line height and at present there is conflict concerning-these dimensions. Primarily, this thesis is concerned with the establishment of the minimum line-to-ground clearances of EHV ac and dc transmission lines. These clearances are established in terms of the electric field under the line based on the "electric field recognition level". Equations are derived for the electric field, and potential at any point below the line in Chapter 2. These equations are then used in Chapter 3 to show the effect of conductor spacing, height and size on the field. Also, the effect of sky wires and bundle conductors is noted. Chapter 4 derives an allowable value of electric field which is used in Chapter 5 to derive the required heights. Chapter 6 considers a reduction of these clearances or induction effects using ground wires below the line conductors for shielding purposes. Experimental readings are obtained in Chapter 7 to verify the equations derived in Chapter 2 and the effects of sky wires and bundle conductors on the electric field below the line. Chapter 8 establishes right-of-way widths based on induction effects. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

No description available.

M.Ing. / Variable liquid resistors are utilised in the rotor circuit, to control mine winders using slipring induction machines. These liquid resistors have a number of disadvantages, therefore a new drive technology is required to replace liquid controllers. A number of machine drives are discussed and a comparative study is made. A 22kW resistively loaded buck chopper in the rotor, is used as a case study. Full design details and procedures are given for the chopper. These designs are verified by simulations and experimental results. A current control was designed and implemented for the buck chopper in the rotor, using a PI controller and pulse width modulation. The 22kW resistively loaded buck chopper operated exceptionally well and it is evident that it could be a viable method for replacing liquid controllers. The oscillation generated in the hoist cables are discussed and a possible counter acting acceleration method of removing these oscillations is described. A rotating oscillation system was designed and constructed for experimental purposes. From the tests undertaken on the experimental system, it was evident that by the implementation of the counter action process, it is possible to remove the oscillations in the hoist ropes.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1963. / Typescript. Vita. Includes computer source code. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 137-138).

Thesis (M.S.)--University of Wisconsin--Madison, 1948. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf [44]).

Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.