同步发电机励磁系统控制性能评估研究

Research on Control Performance Evaluation of Synchronous Generator Excitation System

在同步发电机励磁控制系统的运行中,存在着随时间推移和工况变动等因素发生性能退化现象。这种退化现象会对电力系统稳定性造成影响。研究对励磁控制系统的性能进行监控和评估,可有效避免电力系统失稳问题。由于广义预测控制显式算法要做多步预测,就必须多次求解丢番图方程,因要经过繁琐的中间运算,所以工作量较大,对于动态变化较快的同步发电机励磁系统控制的实时性大大降低。为解决上述问题,通过分析励磁系统控制量与控制目标函数之间的内在联系,找出了最优的模型预测结构,建立了归一化的GPC性能指数指标,避免了丢番图方程的展开运算,从而对监控过程中的控制性能进行评估。最后,通过MATLAB软件对含励磁系统的同步发电机广义预测系统进行仿真研究,结果表明上述性能评估方法能够及时地发现控制系统的性能变化情况,并且与在线求解丢番图方程法做对比验证了该方法的准确性,并且简化了在线求解丢番图方程法所带来的大量中间运算,减少了计算工作量,具有较好的应用前景。

The research on the performance of excitation control system for monitoring and evaluation can effec- tively avoid the instability of power system. Therefore, based on the analysis of excitation system control relationship between quantity and control objective function, we found the optimal model prediction structure, established the normalized GPC performance index, and avoided the complicated operation of Diophantine equation, thus the process monitoring control performance was evaluated. Finally, simulation research on excitation system of synchronous generator generalized predictive system was conducted with MATLAB software. The results show that the performance assessment method can be found in a timely manner to control performance of the system changes, solved with the online lost Diophantine equation method, and thus has good application prospects.