Investigation Of Optimal PMU Placement In Power System

The advent of phasor measurement unit (PMU) based on the GPS technology, has stimulated the rapid development of Wide Area Measurement System (WAMS) in recent years. In WAMS. the phase angle can be measured by PMU with high accuracy in a unified time scales, and meets well two requirements of the development of power system in the future synchronous in time and WAN in space, and thus has been increasingly wider application in state estimation, fault location, transient stability relates to the field of power system safe and stable operation and has become a hot research spot at home and abroad.This paper studies the optimal PMU placement in power systems, the main contents are as follows:(1) State estimation is the basis to ensure safety and stability for power system. This paper presents a model of optimal PMU placement based on0-1integer programming from the perspective of system full observability. In this model, PMU with limited number of channels constraints is considered, as well as zero injection. Adopting the degree of bus voltage and line power flow constraints violations in the post-contingency as filtering index, the set of key contingencies can be obtained by critical line screening technique. Thus the line set of traditional N-1checking is narrowed. Numerical simulation are respectively conducted on IEEE14-bus,30-bus,57-bus.118-bus system, A province power grid500kV system ZJP76(76buses) and power grid220kV ZJP543(543buses). Comparing with the N-1condition (line outages), the proposed method reduces effectively the number of PMU configuration, and improves the reliability and economic efficiency of the system;(2) Fast and accurate fault location can improve the reliability of grid operation, and reduce the losses due to power failure. Learn from the results of previous studies--a fault location algorithm based on traversal search technology, and proposes a set of PMU configuration rules which is suitable for fault location, especially taking the system with ring circuits into consideration. Simulation calculation of ZJP76and ZJP543confirms the effectiveness of the proposed configuration method;(3) Based on eigenvalue method, it proposes PMU configuration for power system small signal stability. It obtains the eigenvalue modal group deployed with the help of the simulation software PSASP, elected correspondingly the PMU configuration of generator set which has the largest correlation factor. The parameters of generator set can be easily adjusted based on PMU measurement data easily to improve the small signal stability;(4) It establishs the integrated model with0-1integer programming, which is suitable for state estimation, fault location and small signal stability. The final configuration can be obtained through the CPLEX software. Compared with each application, the required number of PMU under the multi-application constrained configuration significantly decreases, thus it improves the economy, under the premise of guaranteeing function.