A Novel Method For Electromagnetic Torque Calculation Applying Positive And Negative Sequence Current Vectors

With the forthcoming global energy crisis, the nuclear power has a broader range of the applications. At the same time, the safe operation of the nuclear turbo-generator, particularly the calculation of the rotor shaft vibration, becomes incredibly important. This paper takes a nuclear power turbo-generator as an example and the finite element calculation model has been built up. During the process of the analytic algorithm, the current vector caused by the rotating rotor is replaced by the three-phase current vector induced by the static rotor windings. When symmetrical component transform and dq0 transform employed, the impact of positive current vector and negative current vector on the constant and second harmonic part of the electromagnetic torque has been discussed. Then a novel method for second harmonic electromagnetic torque calculation has been proposed. The data of the finite element algorithm is consistent with that of analytic algorithm, verifying the correctness of the method proposed by this paper.