Optimization of Intial Values of Mechanical Variables of Turbine-Generator Units in an Electromagnetic Transients Program

When using the well-known BPA electromagnetic transients program to study the behaviour of turbine-generator units, one must foresee a settling time for the mechanical variables. By an optimal computation of the initial values of these variables a minimal settling time is achieved. The method rests upon the determination of a correction vector of minimal length by a singular value decomposition technique to be applied to available steady-state values. By this method, which has been implemented in a version of this electromagnetic transients program, parasitic oscillations in steady-state have been eliminated. The magnitude of the necessary corrections may be used as a measure for testing the choice of the time increment.