水力发电系统面向对象建模与运行特性分析

Object-oriented Modeling and Analysis on Operation Characteristic of Hydropower System

针对电网参数波动对水力机组运行特性影响的问题,建立了水力发电系统水力、机械及电气联合计算数学模型,计算方法采用2阶精度的预测-校正法,使用面向对象的程序设计语言VC++,对系统中各个环节进行编程,然后采用封装技术,将每一个环节图形化,并建立通用的图形库。结果表明:电网电压的波动对发电机功角、发电机d轴电压、q轴电压的影响比较明显,电网频率的波动对发电机功率、机组转速及调压室水位的影响较大,电网相角的波动会引起机组各种运行参数的波动,但能恢复到原来的平衡状态。系统发生扰动时,水力、电气运行参数通过调节系统和励磁系统的调节互相影响,其中发电机电气参数的波动频率与水击波频率一致。

Aimed at the effect of operation characteristic of the unit under the fluctuation of the power network,a united computational model of hydraulic,mechanical and electrical parts in the hydropower system was built,and the two-order predictor-corrector method was used to assure both of the computational precision and speed.The object-oriented programming language VC + + was used to write the program of the each part,and enclosed into an icon,sequentially,the universal icon library for the hydropower system was established.It was shown that the power angle,d-axial voltage and q-axial voltage of the generator are clearly affected by the fluctuation of the power network voltage,and the power,the rotating speed of the generator and the water level in surge chamber are observably influenced by the fluctuation of the power network frequency,the fluctuation of the power network phrase angle can lead to the fluctuation of the operation parameters,but it can come back the previous balance condition.While the power network fluctuates,the hydraulic and electrical operation parameters will affect each other by the adjustment of the governor and the excitation system,and the fluctuation frequency of the electrical parameters of the generator is equal to the natural frequency of the water hammer.