EFFICIENT CALCULATION OF ELEMENTARY PARAMETERS OF TRANSFORMERS

Very efficient procedures for computing elementary parameters (turn leakage inductances and capacitances) in a transformer are presented. The turns are used as a calculation base to permit modeling at very high frequencies. Turn-to-turn (or loop) leakage inductances are obtained by an image method. The charge simulation method is used for finding the capacitances between turns and from turns to ground. The new methods are very efficient compared with the use of the technique of finite elements and are also remarkably accurate. Thus, the short circuit (or test) leakage inductance can be obtained from turn-to-turn information. Examples of calculated parameters are given for illustration. For validation, the results are compared with the parameters obtained using finite elements and tests. The elementary parameters can be used to create reduced order computational models for the calculation of transient phenomena.