The Pmu Power Flow Calculation And Estimation Of The Contribution

Global Positioning System, i.e. GPS, has been utilized at the beginning of the nineties of the twenties century. Based on its rigorous same time benchmark, Phasor Measurement Unit (PMU) was successfully manufactured. PMU can accurately measure voltage phasor and ampere phasor.At present, the domestic and overseas do a lot of studies on the design of the PMU device. The PMU, which has been used in some networks shows its superior characteristics. Based on the information provided by PMU, the Wide Area Measurement System (WAMS) are realized conveniently, which make the analysis of obeservability, supervision and control on system much easier. However, it's impossible to set up PMU at every bus, limited to the price, condition and communication. In addition, there are unavoidable errors in measurements of PMU, an artificial equipment, so what effects should be produced while the PMU is used in the traditional state estimate.Thesis analyzes and studies the basic problem that PMU makes an impact on the power system observability and the traditional state estimate. It includes the realization to solve the power flow node by node and the improvement on the precision of the state estimate.When the PMU devices are accurate, the measurement is regarded as real state variables. Under the assumption, the power flow can be sovled node by node without iteration by the proper placement of the PMUs. To solve this problem, the new concept of dynamic incidence-degree is proposed. And based on this idea, the static and semi-dynamic optimal algorithms are derived, as well as their programs. A lot of examples tests show that the method is effective. In addition, the block decoupled problem is discussed in the corresponding part in order to meet the trend of interconnection of the large network.When there are errors in the PMU measurements, they can not substitute the real...