Research And Application Of Electric Power System Key Technology

The revolution of electric power system has brought a new big round construction, which is pushing the greater revolution of electric power technique along with the application of new technique and advanced equipment. Especially, the combination of the information technique and electric power technique, to great extent, has improved reliability on electric quality and electric supply. The technical development decreases the cost on electric construction and drives innovation of electric network. On the basis of national and international advanced electric knowledge, the dissertation introduces the research hotspot for present electric power syetem as following. Firstly, This dissertation introduces the building condition of distribution automation (DA), and brings forward two typical construction modes on DA construction, integrative mode and fission mode .It emphasizes the DA structure under the condition of the fission mode and presents the system configuration, the main station scheme, the feeder scheme, the optimized communication scheme etc., which is for DA research reference. Secondly, as for the (DA) trouble measurement, position, isolation and resume, This dissertation analyzes the changes of pressure and current for line problem, gets math equation by educing phase short circuit and problem position under the condition of single-phase and works out equation and several parameter (U|·)_s, (I|·)_s and (I|·)_e table on problem . It brings out optimized isolation and resume plan, realizes auto isolation and network reconstruction, reduces the power off range and time and improves the reliability of electric power supply through problem self-diagnoses and self-analysis. It also introduces software flow and use for problem judgement and sets a model on network reconstruction and computer flow. Thirdly, electricity system state is estimated to be one of the key techniques in DA realization. The dissertation recommends the resolvent of bad measurement data and structure mistake on the ground of describing state estimate way. It also advances a practical test and judging way on topology mistake in state estimate about bad data test and abnormity in state estimate as well as the problem and effect on bad data from state measure to state estimate .As for real time monitor and control problem, the dissertation introduces a new way to solve them by electricity break and exceptional analysis, and the way has been tested in Weifang DA. Fourthly, about the difficulty for building the model of load forecasting, big parameter scatter limit and something concerned, the dissertation introduces some parameters, eg. weather factor, date type and social environment effect based on analysis of routine load forecasting and means. It presents the way for electricity load forecasting founded on neural network(ANN),which has been tested it's validity by example and made to be good practical effect. Fifthly, concerning the lack of concordant wave on preventing concordant wave and non-power compensation and non-continuity on compensation, there is a topology structure of PWM main circuit and non-power theory on active filter the waves technique and builds flat proof on the ground of Saber Designer and proves to be practical. Meanwhile, it analyzes and designs the way of non-power need of electric network trends and decreasing line loss combined with DA, which have been tested its objective economic benefit through counting example. Sixthly, not only do the dissertation design a way founded on the magrginal electric price fitted to our present national electric power market with regards to future trends of electric power market in China and fair trade under the government surveillance, that is group competition in short-term trade under the way of grouped price and quantity harmony, but also puts forward combination arithmetic, math model of trading plan and safty economical restriction. It can solve the original contradiction between medium and long term contract price and short term competitive price with improvement on competitive percentage and cut down the unfair income difference of electric factory, at the same time, it can optimize the electric limit for all electric factories and reduce the total purchase charge of electric power from burthen curve of whole electric market network.