Operational Inductances of Turbine-Generators by the Finite-Element Method

As part of EPRI Program, RP 1288-1, Improvement in Accuracy of Prediction of Electrical Machine Constants, a method has been developed for calculating small-signal, terminal, operational inductances. The method is based on solutions to the magnetic diffusion equation by the finite-element method. To faithfully simulate the behavior of the rotor iron for small signal perturbations, measured values for incremental permeability are used. A finite-element grid tailored to handle the skin effect at frequencies up to 100 hertz has been developed. The paper is semi-tutorial in nature and is intended as a basis for future papers, which will compare the results of calculations by this method to test data. Sample flux plots are given, and examples of the frequency dependence of operational inductances are shown.

[1]  A. Ray.  Magnetic Circuit Design of Saturated Electrical Machines By the Finite-Element Method , 1981, IEEE Transactions on Power Apparatus and Systems.

[2]  M. V. K. Chari,et al.  Finite-Element Solution of the Eddy-Current Problem in Magnetic Structures , 1974 .

[3]  H. S. Cabayan,et al.  Efficient Techniques for Finite Element Analysis of Electric Machines , 1973 .

[4]  J. A. Mallick,et al.  Modeling of Solid Rotor Turbogenerators Part I: Theory and Techniques , 1978, IEEE Transactions on Power Apparatus and Systems.

[5]  S. H. Minnich,et al.  Incremental permeabilities for transient analysis of large turbine generators by the finite-element method , 1981 .

[6]  K. J. Binns,et al.  Prediction of load characteristics of turbogenerators , 1978 .

[7]  K. J. Binns,et al.  Determination of saturated reactances of turbogenerators , 1980 .

[8]  J.W. Dougherty,et al.  Finite Element Modeling of Large Turbine Generators; Calculations Versus Load Test Data , 1981, IEEE Transactions on Power Apparatus and Systems.

[9]  P. Kundur,et al.  Adaptation and Validation of Turbogenerator Model Parameters Through On-Line Frequency Response Measurements , 1981, IEEE Transactions on Power Apparatus and Systems.

[10]  S. Salon,et al.  The Application of Poynting's Vector to the Determination of Synchronous Machine Impedances , 1980, IEEE Transactions on Power Apparatus and Systems.

[11]  S. J. Salon,et al.  Calculation of Induced Field Current and Voltage in Solid Rotor Generators , 1978, IEEE Transactions on Power Apparatus and Systems.

[12]  S. Tandon,et al.  Load Characteristics of Synchronous Generators by the Finite-Element Method , 1981, IEEE Transactions on Power Apparatus and Systems.

[13]  M. Chari,et al.  Finite Element Solution of Saturable Magnetic Field Problems , 1970 .

[14]  A. Hannalla,et al.  Steady State Short Circuit Characteristics of Turbine-Generators from Design Data Using Field Calculations , 1980, IEEE Transactions on Power Apparatus and Systems.