基于PMU的状态估计的研究

传统的状态估计是基于单相纯正弦模型的,但实际电力系统的三相并不是完全对称,这就导致了传统的状态估计存在着固有的误差。随着基于GPS同步相量测量单元(PMU)的应用和计算机技术的发展,该文提出了一种以PMU为基础的三相状态估计和谐波状态估计算法以消除这种固有误差。利用PMU的电压幅值测量值和相角测量值与SCADA原有的测量值构成的混和量测系统一起用于状态估计,从而提高网络的可观测性及状态估计的精度,来弥补传统状态估计的不足。所以这种算法可根本解决系统三相不平衡和状态向量非纯正弦带来的误差问题。最后讨论了对该算法的评估方法。

Research on state estimation based on PMU

The conventional state estimation based on network of single phase and pure sinusoids voltage waveforms has inherent biases. With the application of Phase Measurement Unit(PMU) based on GPS, this paper provides three-phase state estimation and harmonic state estimation algorithms based on PMU for solving inherent biases. The proposed algorithms utilize the measurement system that is made of voltage amplitude measurement value and phase measurement value of PMU and the existing measurement value of SCADA to state estimation, which can raise observation of network and precision of state estimation and compensate the deficiency of traditional state estimation. This algorithms can essentially solve the error because of unsymmetric three-phase and impure state vector. The evaluation method to the algorithms is also discussed.