A Theoretical and Practical Study of the Lorenz-type Inductor-alternator

Abstract

Throughout this work the emphasis is laid on developing the theory in a form which contributes directly to the design technique; each stage is verified experimentally. Relevant literature falls into two distinct categories: one, classical in form, based on the permeance of assumed magnetic circuits: the second, presenting computed solutions to models of detailed field problems. This thesis extends the classical approach to bring its capacity for analysis closer to the level of detail offered by the model/solution concept. After a full analysis of these theories, the experimental machine's design, manufacture and instrumentation are reported, Problems connected with 'damping undesirable flux variations' and ‘accounting for anomalous loss mechanisms' formed ‘the original investigation. Their solution is presented in the complete analysis of tooth and core flux distribution, which leads to a detailed description of the on-load flux density distribution across the surface of a rotor tooth. The theory derived to solve these early problems is extended to form an alternative technique to existing practice in the complete solution of the loaded machine. The expressions combine the load current and voltage with the field current and, in addition, are dependent on the airgap geometry, the load circuit power factor and the leakage reactance. By expressing the parameters in two equations, one limited by the load conditions and the second dependent on the characteristics of the particular machine, successful predeterminations of field requirements for practical non-linear conditions are obtained. A paper on the history and changing fortunes of this class of machine is included, demonstrating its unique character and contribution to technology. From a research viewpoint great potential lies in the combination of medium frequency and an unusual airgap geometry; this has allowed the detection and analysis of characteristics which, in other types of machine, are individually unidentifiable.