基于风力机特性的风电机组潮流计算

Power flow analysis of wind power generator based on wind turbine characteristics

在风力机特性方程和异步发电机的稳态等值模型基础上,建立了基于风力机特性的风电机组潮流计算数学模型。考虑风力机特性方程中的风力机机械力矩和发电机电磁力矩平衡,将风电机组引入处作为功率可变的PQ节点,异步发电机则作为RX等值电路模型,进行了风电机组的潮流计算。该方法引入定子电压,定子电流和转子滑差的修正量,将风力机特性方程中的风速、风能利用系数、尖速比等相关参数引入到潮流计算过程中,通过与常规的牛顿-拉夫逊潮流计算相结合,修正相应的雅可比矩阵来完成,从而保证了潮流计算迭代过程的完整性。该模型既具有传统风电机组RX模型的优点,又可以保证牛顿-拉夫逊方法的平方收敛性。最后,通过2个算例进行了潮流计算,证明了其正确性。

A power flow analysis model is established for wind power generator based on the wind turbine characteristic equation and the steady- state equivalent model of asynchronous generator. Considering the balance of mechanical torque and electromagnetic torque ,it regards the bus of wind power generator as variable- power PQ node and the asynchronous generator model as RX steady -state equivalent model. The corrections of stator voltage,stator current and rotor slip,as well as the wind turbine parameters of wind speed,performance coefficient and tip speed ratio,are used as the inputs of power flow calculation and the integrality of iterative process is guaranteed by modifying the Jaeobian matrix of conventional Newton- Raphson power flow analysis. This method keeps the merit of RX model and Newton-Raphson＇s quadratic convergence. Its correctness is verified by two test systems with wind power generators.