Research On Optimal PMU Configuration Method Based On Complete Observability Requirements Of Power Grid

With the continuous development and improvement of the transmission network and its related technologies,the transmission network has become more complex than ever.The automation equipment of transmission network is based on the accurate real-time monitoring of the states of the system.Real-time monitoring requires faster and more accurate measuring devices.In recent years,with the improvement of the synchronous measurement technology(SMT)in which uses the GPS signal to synchronize all measurements,the performance of phasor measurement unit(PMU)is gradually improved as well as the cost is reduced.Therefore,it is now feasible to place PMUs in large power networks.PMU can provide highly accurate real-time voltage and current phasor measurements because its skewness error is minimized via synchronization.Thus,using PMUs to perform state estimation would significantly improve the estimation accuracy and make it possible to obtain the estimate of the states in real-time..However,the premise for state estimation is that the system is completely observable.That is,the solution of a set of state can be unique determined by the existing measurements.In the other situation,it may be necessary to provide a set of redundant measurements to ensure that state estimation can be performed in the case of measurement losses or device failures.At present,most of the existing optimal PMU placement methods have only studied the PMU placement in typical simulation systems,ignoring the complexity of the actual power system network.Therefore,it is of great theoretical and practical significance to study how to realize the complete observability of the system by configuring PMU and other traditional measuring equipment.Regarding to the problem,this Thesis integrates the typical optimal PMU placement strategies with various placement objectives,and integrates different methods into an optimal placement tool by the GUI of MATLAB.In this paper,the PMU optimization configuration problem is analyzed in detail,and a solution model of optimal PMU configuration problem is constructed.The optimal PMU configuration problem is transformed into an optimization problem.The optimal PMU configuration results is obtained by solving the linear programming algorithm.Secondly,an optimal PMU configuration tool based on MATLAB is developed.Through program optimization and data redundancy processing,the tool can quickly determine the optimal PMU configuration position of the system to ensure the complete observability of the system.The tool was simulated and verified by setting different PMU configurations on the IEEE-14 node example system.The analysis confirmed the reliability and rationality of the tool.Finally,with the information of the Electricity Ten Years Statement(ETYS)of Actual Transmission Network,the topology of the real system are obtained based on some assumptions.The optimal PMU placement of the real power system under different conditions is obtained by using the optimal PMU placement tool,then the results are analyzed in order to make suggestions for the actual PMU placement work.The simulation results of the example verify the effectiveness of the PMU configuration algorithm and tools,and achieve the goal of quickly obtaining the fully observable PMU optimal configuration results,which is of great significance for further improving the overall observability of the power grid.