计及小干扰稳定约束的互联系统AGC最优经济控制策略

Optimal Economic Control Strategy of AGC in Interconnected Power System with Small Signal Stability Constraints

为了在保证互联系统小干扰稳定的前提下提高系统调频的经济性,提出了基于双层模型控制结构的多区域互联系统自动发电控制(automatic generation control,AGC)最优经济调频控制策略。首先上层控制基于全网层面,以消除系统频率偏差为首要目的,建立了多区域AGC协调控制优化模型,并采用非线性规划算法求解该优化模型。然后下层控制中充分考虑系统的动态稳定性,建立了计及小干扰稳定约束的AGC指令最优分配模型,并提出了基于改进策略的优化算法求解该模型。最后,通过修改后的IEEE-30节点配电网算例对所提策略的有效性进行验证。结果表明,该策略在提高互联系统调频经济性的同时,使得系统满足小干扰稳定的要求;所提出的算法改进策略改善了算法的收敛性,并且在保证计算精度的前提下提高了优化速度。

In order to improve the economy of frequency regulation of the interconnected power system on the premise of ensuring the small signal stability, we put forward an optimal coordination frequency control strategy of automatic generation control(AGC) in multi-area based on bi-level model control. Firstly, based on the whole power grid, taking eliminating the system frequency deviation as the primary purpose, we establish an optimization model for coordination frequency control of multi-area AGC in the upper layer, and adopt the nonlinear programming algorithm to solve the optimization model. Then, considering the dynamic stability of power system, we establish an optimization allocation model of AGC command with small signal stability constraints in the lower layer. Moreover, to solve the established optimization model, we propose an improved strategy based on a nonlinear programming algorithm. Finally, based on the improved IEEE-30 bus distribution network, the validity of control strategy is verified. The results show that the proposed control strategy improves the economy of interconnected system frequency regulating and ensures that dynamic performance of system meets the demands of analysis on small signal stability. The improved algorithm strategy improves the convergence property, and improves the computation speed when ensuring the optimization accuracy.