汽轮发电机组轴系扭振的独立模态空间鲁棒控制

INDEPENDENT MODAL SPACE ROBUST CONTROL OF THE SHAFT TORSIONAL OSCILLATION OF TURBINE-GENERATORS

提出在汽轮发电机组轴系扭振的独立模态空间控制回路中,采用H∞扭振模态观测器估计模态反馈信号。证明了独立模态空间控制器可以独立设计,而引入H∞扭振模态观测器对闭环系统极点分布的影响可以忽略不计。基于H∞控制理论导出了针对受控扭振模态设计的独立模态空间控制器 的鲁棒稳定条件。另外,出于实际考虑,建议扭振控制转矩以发电机电磁转矩分量的形式实现,而将慢变的机械转矩看作干扰,提出了抑制其影响的H∞性能指标。在此基础上提出轴系扭振的独立模态空间鲁棒控制,并归结为带有闭环极点配置约束的多目标H∞综合问题。算例仿真表明,轴系扭振独立模态空间鲁棒控制策略是可行的、有效的。

The Hinfinity torsional modal observer is adopted to estimate the feedback modal signals in the independent modal space (IMS) control loop of the shaft torsional oscillation of turbine-generators. It is proved that the IMS controller can be designed independently, while the inserted Hinfinity torsional modal observer has little influence on the distribution of the poles of the closed loop system. Robust stability condition of the IMS controller designed for the controlled torsional mode is derived based on the Hinfinity control theory. Moreover, for practical consideration, it is suggested that the controlling torque should be implemented as the component of the generator electromagnetic torque, while the slow dynamic behavor of the mechanical torque is considered as a kind of disturbance. One Hinfinity performance specification is proposed to suppress the disturbance. On the basis of the above study, an IMS robust control of the shaft torsional oscillation is developed and formulated as a multi-objective Hinfinity synthesis problem. A case study is given to show that the IMS robust control of the shaft torsional oscillation is feasible and effective.