Model of a converter-fed 2x3 phase synchronous machine motor drive. Part 2: EMTP implementation

摘要

This report is the second part of a Ph.D. report dealing with modelling of variable speed motor drives. It documents the implementation of a model of a converter-fed 2x3-phase synchronous machine motor drive in the EMTP. The motor drive model itself including models of all involved components has been developed in the first part of the Ph.D. report. The EMTP (Electro Magnetic Transients Program) is briefly presented, and the trapezoidal solution method of the EMTP is explained including the possibilities to include more or less damping in the solution method. The inherent risk of numerical oscillations for the trapezoidal method of integration is explained together with some ways to deal with that problem in general. A special way (based on critical damping adjustment for the individual models) to deal with this oscillation problem when implementing user-defined models through the MODELS interface is presented. The 2x3-phase synchronous machine model and the line-commutated 6-pulse converter is implemented in FORTRAN program that are linked to the EMTP via the MODELS interface. In order to ensure numerically stability in the EMTP some necessary detection and snubber circuits are developed. A small preprocessor to generate the necessary EMTP data lines for the motor drive model is developed. The other parts of the motor drive model are implemented in the EMTP using among other things the MODELS facilities. The EMTP data case for the motor drive is briefly various events. However the descriptions are only enough as a users guide for an experienced EMTP user. (EG)