中文摘要：

推导了水轮发电机组的电磁力矩和电磁刚度的表达式,建立了考虑转子支臂刚度并在水力转矩和电磁力矩耦合作用下的轴系统机电耦联扭振模型。研究了轴系统扭振特性随转子转动惯量、支臂刚度、转轮水体附加质量的变化规律。分析了不同频率的水力激励对转子扭振响应的影响规律,得出了轴系最大扭矩内力、扭振角和电磁力矩的频响曲线。研究水力激励频率等于零频和一阶频率时的机电耦联共振特性,给出了激磁电流和内功率角对扭振的影响,揭示了机电耦联振动规律,为水电机组的设计与安全稳定运行提供理论依据。

英文摘要：

This paper derives expressions of electromagnetic torque and electromagnetic stiffness with energy method and develops a mechanical-electrical coupling torque vibration model for a hydro generator shaft system under hydraulic and electromagnetic excitations,focusing on a study on the effects of rotor moment inertia,spiders′ stiffness,added mass of water and hydraulic excitation frequency.Frequency response curves of shaft torque,torsional vibration angle and electromagnetic torque are presented,including the mechanical-electrical coupling resonance to hydraulic excitations of zero and first order frequencies and the influences of excitation electric current and internal active power angle.These results provide a reference for design and stable operation of hydro generator set.