Recent developments have shown that numerical models of synchronous machines are, in many cases, improved by introducing an increased number of dampers or dynamic constants. The major issues affecting the model identification by such an extension, which in fact becomes necessary when the machine possesses a solid rotor are discussed from a time-domain point of view. The first result is that all methods which determine the equivalent circuit from test data in an indirect manner, by using the time constants or operational impedances as intermediate tools, give rise, along the d-axis, to systematic errors in the sub-transient and sub-subtransient time constants of the estimated circuits. Unfortunately, when the identification experiment is the standard short circuit, even the direct method suffers from the drawback of weak identifiability of the model, with the result that the uniqueness of the equivalent circuit, directly estimated from test data, is not at all guaranteed. In fact, from an information content point of view, the richer tests are those made at standstill, with a perfect decoupling between the two axes. It is demonstrated by simulation that if the direct approach is applied to such a test, with pulse wave modulated (PWM) voltages as the excitation signals, a numerically cheap and accurate one-step procedure for time-domain identification of circuit models is obtained.

Identification of generalised models of synchronous machines from time-domain tests

The paper examines the virtues of representing the magnetising curves of a switched reluctance motor by customised cubic splines and storing its coefficients in a new data base. It is shown that cubic splines are capable of handling the highly nonlinear characteristics. Furthermore they are found to be well suited for computer efficient generation of the flux linkage/current, torque/angle and current/flux linkage functions as required for drive simulation purposes. A case study demonstrating the use of the new data base as well as its compilation is discussed.

New data base for switched reluctance drive simulation

/pdf/on-the-losses-in-a-high-speed-permanent-magnet-generator-509g1qdhkx.pdf

On the losses in a high-speed permanent-magnet generator with rectifier

In the global, rather simple model of the synchronous machine with rectifier developed before, saturation phenomena were not taken into account. Here, a possible way of extending the machine model with saturation is described. Starting with the derivation of the separate models of the synchronous machine and the rectifier, a steady-state model and a dynamic model are derived. The dynamic model is a global model, in which very fast phenomena, such as the ripple on the direct current, are neglected. Hoeijrnakers, M,J. A POSSIBLITY TO INCORPORATE SATURATION IN THE SIMPLE, GLOBAL MODEL OF THE SYNCHRONOUS MACHINE WITH RECTIFIER. Faculty of Electrical Engineering, Eindhoven University of Technology, The Netherlands, 1989. EUT Report 89-E-225 Address of the author Dr.ir. M.J. Hoeijmakers, Electromechanics and Power Electronics, Faculty of Electrical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands

/pdf/a-possibility-to-incorporate-saturation-in-the-simple-global-3d6d9yjzbb.pdf

A possibility to incorporate saturation in the simple, global model of a synchronous machine with rectifier

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/pdf/the-use-of-petri-net-theory-for-simplexys-expert-systems-25ofeyse71.pdf

The use of Petri net theory for simplexys expert systems protocol checking

• A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers.

MJ Martin Hoeijmakers

Papers

A possibility to incorporate saturation in the simple, global model of a synchronous machine with rectifier

On the steady-state performance of a synchronous machine with convertor : with special attention to wind energy conversion systems