汽轮发电机组轴系模型的降阶处理与分析

目前用于分析汽轮机组轴系暂态扭力矩的轴系数模有按原动机、发电机，励磁机自然分块的集中质量模型、多段集中质量模型和连续质量模型．多段集中质量模型在一定程度上协调了其它两种模型的优劣，但如何建立合理的多段集中质量模型至今尚无系统有效的方法．本文采用平衡降阶法对高阶轴系数模型进行了简化，并将该方法和最优Ｈａｎｋｅｌ范数近似相结合，对降阶前后系统频率响应误差给出了准确的分析．所得降阶模型可用于汽轮机组在系统发生各种故障及非同期合网时轴系暂态扭力矩的计算．由算例结果可见阶数不同的降阶模型对于各种扭力矩计算结果的影响．

Model Reduction of Turbo-generator's Shaft

Based on balanced state-space representations, a model reduction method for establishing a multi-mass model of turbo-generaic's Shaft is proposed in this psper. Combining with Hankel norm approximation analysis, this method gives an accurate mean to analyse the frequency response error caused by reduced model Transient torsional torques under two different fault conditions and with reduced shaft modeel of different order arc calculated. Effeet of the order on the shaft torques is illustrateel.