【摘要】：隨著交直流輸電技術的發(fā)展和電網(wǎng)容量的不斷增大,電網(wǎng)的穩(wěn)定問題日益尖銳。交直流輸電技術需要一定量的無功功率電源作支撐;電網(wǎng)容量的增大使得線路上傳輸?shù)臒o功功率增大,故障后所需的無功功率支撐也變大,這些都使得電力系統(tǒng)的運行穩(wěn)定性嚴重惡化。同時,受端電網(wǎng)中用電量大的工業(yè)用戶(如生產(chǎn)鋁和各種稀有金屬的企業(yè))也可能對系統(tǒng)的穩(wěn)定產(chǎn)生不良影響。鋁電廠在電壓嚴重下降時需要降低本身的用電負荷,而帶有大量重負荷的異步電動機,當無功補償特別動態(tài)無功補償不足時,容易引起電壓崩潰。為提高受端系統(tǒng)的電壓穩(wěn)定性,需要對系統(tǒng)進行動態(tài)無功補償。而這需要解決動態(tài)無功補償優(yōu)化配置過程中的布點、容量等問題。圍繞以上問題,本文開展了以下幾方面研究。本文首先從研究電壓薄弱區(qū)域角度的出發(fā),利用K-means聚類技術和靈敏度分析方法,研究系統(tǒng)的關鍵故障和無功配置靈敏節(jié)點。此方法能夠在之后無功配置的優(yōu)化過程中,縮小變量的維度,提高計算效率。為了定量評估實際大規(guī)模電網(wǎng)暫態(tài)電壓穩(wěn)定性,論文接著從暫態(tài)電壓穩(wěn)定的判據(jù)出發(fā),分析故障后節(jié)點電壓曲線的變化,提出用于判斷節(jié)點和系統(tǒng)電網(wǎng)穩(wěn)定性的指標。指標的計算可直接利用實際系統(tǒng)運行過程中進行的故障時域仿真結果數(shù)據(jù),無需額外的仿真分析。同時該指標能夠直接衡量系統(tǒng)在不同安裝位置和不同安裝容量下,系統(tǒng)的電壓穩(wěn)定性強弱,以量化計算安裝無功補償裝置后系統(tǒng)的暫態(tài)電壓穩(wěn)定性。其次,為了兼顧各種性能指標,論文提出一個多目標優(yōu)化模型,并基于NSGA-Ⅱ算法得到模型最優(yōu)解的Pareto前端,作為無功補償裝置安裝配置方案的最優(yōu)解群�？紤]到新型電力負荷設備的大規(guī)模應用,對供電系統(tǒng)電壓質(zhì)量提出了更高要求。論文提出基于質(zhì)量工程理論的質(zhì)量損失函數(shù),對電壓驟降引起的國民經(jīng)濟損失進行評估,從而將故障后的電壓穩(wěn)定狀況轉(zhuǎn)化為經(jīng)濟費用指標,在最優(yōu)解的Pareto前端的基礎上,對動態(tài)無功補償進行最終優(yōu)化。實現(xiàn)無功補償裝置在實際系統(tǒng)中技術性和經(jīng)濟性的統(tǒng)一。
[Abstract]:With the development of AC / DC transmission technology and the increasing of power network capacity, the problem of power network stability is becoming more and more acute. The AC / DC transmission technology needs a certain amount of reactive power supply as the support, the increase of the power network capacity makes the reactive power transmission on the line increase, and the reactive power support after the fault becomes larger. All these make the operation stability of power system deteriorate seriously. At the same time, industrial users (such as those producing aluminum and various rare metals) who consume large amounts of electricity in the receiving grid may have a negative impact on the stability of the system. When the voltage of aluminum power plant drops seriously, it is necessary to reduce its own electric load, but the asynchronous motor with a large amount of heavy load will easily cause voltage collapse when the reactive power compensation is especially dynamic and reactive power compensation is insufficient. In order to improve the voltage stability of the receiver system, dynamic reactive power compensation is needed. This need to solve the dynamic reactive power compensation in the process of optimal allocation of points, capacity and other issues. Around above question, this article has carried out the following several aspects research. In this paper, the key faults and reactive power configuration sensitive nodes of the system are studied by using K-means clustering technique and sensitivity analysis method. This method can reduce the dimension of variables and improve the computational efficiency in the later reactive power allocation optimization process. In order to quantitatively evaluate the transient voltage stability of large scale power network, the paper analyzes the change of node voltage curve after the fault, and puts forward the index to judge the stability of power system and node. The calculation of the index can directly utilize the time domain simulation data of the fault during the operation of the actual system without the need for additional simulation analysis. At the same time, this index can directly measure the voltage stability of the system under different installation positions and different installation capacities, so as to quantitatively calculate the transient voltage stability of the system after the installation of reactive power compensator. Secondly, in order to take into account various performance indexes, a multi-objective optimization model is proposed, and the Pareto front end of the optimal solution of the model is obtained based on NSGA- 鈪，

本文編號：2164244