Analysis of the Pole Slipping Operation of Turbo-generator Based on Improved Damping Finite Element Model

摘要

The pole slipping number of the generator is an important indicator related to the safe and stable operation of the power system. The electrical and mechanical systems of the turbine generator body interact with each other and restrict the pole slipping operation of the generator. In order to fully and accurately analyze the electromechanical characteristics of the pole slipping operation, firstly, a mechanical shaft-field-circuit-network coupled time-step finite element model of turbo-generator based on improved damping model was established, and the rationality of the damping parameters was verified by the rotor AC impedance principle. Then the characteristics of the pole slipping operation of the turbo-generator under the improved damping model and the traditional damping model were analyzed through the simulation, and the shaft fatigue life loss caused by the large disturbance was evaluated. Finally, the pole slipping number of the unit under the two damping models was calculated separately. The results show that the improved damping model is more in line with the damping effect of the actual turbine generator, which creates conditions for accurately analyzing the oscillation process after large disturbance and exactly estimating the transient stability and limit cut-off time of the system.