电力系统潮流和最优潮流是典型的非线性计算,需要处理复杂的非线性方程,因此计算量大,求解效率低,且在大电网运行分析领域易出现不收敛情况。线性化模型可以解决上述问题,直流模型是目前应用最广泛的线性化模型,计算速度快,但是计算精度相对较低。基于此,以热启动和冷启动环境为基准,首先对目前比较典型的5种线性化模型进行综述,然后提出一种可以求解更完备潮流信息的线路解耦等值线性化模型。文章首先对5种线性化模型分别进行潮流计算和最优潮流计算,并分别与交流模型计算结果进行对比,从理论和仿真2个角度探讨了各线性化模型的优缺点以及适用场景,验证了所提模型在潮流计算以及最优潮流计算中均具有较高的计算精度,求解效率高,且能够计算更完备的潮流信息,综合表现强于其他线性化模型。
Power flow and optimal power flow of power system are typical nonlinear calculations. They need to deal with complex nonlinear equations, therefore a large amount of calculation with low computational efficiency are needed, prone to misconvergence in calculation of large power grid. Linearized models can solve above problems, and DC models and its improved versions are the most widely used linear models at present. Taking hot-and cold-start environments as references, this paper reviews five kinds of typical linear models, then proposes a line decoupling equivalent linearization model, able to calculate more complete information. Firstly, this paper calculates power flow and optimal power flow of these linearized models, comparing their results with those of alternating current models respectively. Advantages and disadvantages of the linearized models are discussed in two aspects: theory and simulation. The proposed model is proved with better performance than other linearized models in general, such as higher accuracy in power flow and optimal power flow calculations, higher solving efficiency and more complete information in calculation.