Design of a brushless excitation system utilizing pot cores

Abstract

Purpose: The paper is devoted to the optimal substitution of slip rings through an inductive power transfer system (IPT) for field winding supply of generators or motors with a wound rotor. By a rotational pot core transformer approach, the rotor-side energizing of the excitation windings can be provided isolated and free of wear. Design/methodology/approach: For design purpose, an analytical model of the inductive link and the compensation network elements is shown. Based on a pot-core transformer approach, possible types of compensation networks regarding motor-specific constraints were carried out and compared among themselves by parameter studies. The analytical parts of the model were subsequently validated with measured data of an appropriate core and accompanying FEM calculations. On the basis of an experimental prototype system, the approach has been tested both stationary and transient. Findings: The publication exemplifies how a brushless excitation system for generators and motors can be inexpensively designed and implemented. Originality/value: This paper systematically presents a comprehensive analytical approach for brushless excitation systems as well as a prototypical system. Compensation network elements regarding motor-specific constraints were carried out and compared among themselves by parameter studies.