【摘要】：伴隨我國電力事業(yè)的不斷發(fā)展,各區(qū)域電網(wǎng)之間的功率交換越來越頻繁,使得線路的負(fù)擔(dān)日益加重。在此背景下,因故障等因素而發(fā)生潮流轉(zhuǎn)移進(jìn)一步惡化了線路的工作條件,增加了發(fā)生連鎖跳閘的風(fēng)險。為此,本文研究預(yù)防潮流轉(zhuǎn)移引起連鎖跳閘的緊急控制策略,保證后備保護(hù)正確動作從而避免發(fā)生大停電事故,提高電力系統(tǒng)的安全運(yùn)行水平。本文首先基于多支路切除的潮流轉(zhuǎn)移特征,推導(dǎo)了線路潮流計算式,快速識別網(wǎng)絡(luò)中的轉(zhuǎn)移潮流。通過分析正常線路上潮流的組成以及各切除支路間轉(zhuǎn)移潮流的分布差異,給出分別利用等效潮流和虛擬支路模型的方法來簡化開斷潮流的虛擬折返過程,進(jìn)而得到識別故障后轉(zhuǎn)移潮流的計算式。然后根據(jù)線路潮流的構(gòu)成,分別提出了基于等效潮流的嚴(yán)重線路搜索算法和基于潮流轉(zhuǎn)移密集度(FTIL)的嚴(yán)重線路搜索算法。前者采用等效潮流重新建立了一種新的路徑搜索方案,創(chuàng)造性地將路徑搜索擴(kuò)展到多支路切除情況。同時采用路徑擴(kuò)展和修正相結(jié)合的閉環(huán)搜索策略,避免發(fā)生漏選;后者引入FTIL定義了廣義潮流轉(zhuǎn)移嚴(yán)重區(qū),以此簡化多支路潮流轉(zhuǎn)移的分布,并基于廣度優(yōu)先搜索(BFS)算法界定該區(qū)域。將FTIL作為啟發(fā)項引入BFS的終止條件,使節(jié)點(diǎn)擴(kuò)展自動規(guī)避FTIL較小的區(qū)域,提高搜索嚴(yán)重線路的效率。針對線路過載問題,建立了基于虛擬控制單元與啟發(fā)式搜索的減載方案。該方法首先利用同心松弛原理對網(wǎng)絡(luò)進(jìn)行縮減,篩選出優(yōu)先參與調(diào)整過程的設(shè)備和元件;其次引入虛擬控制單位的概念,有效辨識出過載線路間的減載效果差異,提高傳統(tǒng)靈敏度算法的分辨率。然后結(jié)合等量切機(jī)、切負(fù)荷控制策略,提出了最優(yōu)可控單元的啟發(fā)式搜索方法、最佳控制單元調(diào)整量的計算方法以及控制流程;最后采用輪次調(diào)整逐步朝著最優(yōu)減載的方向進(jìn)行調(diào)整直至過載消除,物理意義明確。其中每輪調(diào)整的最優(yōu)控制點(diǎn)與調(diào)整量計算簡單、快速,并在每輪調(diào)整末期將過載量進(jìn)行反饋,實(shí)現(xiàn)閉環(huán)控制。最后以IEEE標(biāo)準(zhǔn)測試系統(tǒng)為例,對本文所提的算法進(jìn)行了驗證和分析。仿真結(jié)果表明,將故障擴(kuò)展到多條線路情況,所提算法均能夠達(dá)到預(yù)期效果,為預(yù)防潮流轉(zhuǎn)移導(dǎo)致的大停電事故提供了較為完整的緊急控制策略,進(jìn)一步提高了電網(wǎng)的安全穩(wěn)定性。
[Abstract]:With the development of the electric power industry in China, the power exchange between the regional power grids is becoming more and more frequent, which makes the burden of the transmission line more and more serious. In this context, power flow transfer due to fault and other factors further deteriorate the working conditions of the line, and increases the risk of chain tripping. Therefore, this paper studies the emergency control strategy to prevent chain tripping caused by power flow transfer, to ensure the correct action of backup protection and to avoid power outages, and to improve the level of safe operation of power system. In this paper, based on the characteristics of multi-branch power flow transfer, a power flow calculation formula is derived to identify the power flow in the network quickly. By analyzing the composition of the power flow on the normal line and the distribution difference of the transfer power flow among the excised branches, the method of using the equivalent power flow and the virtual branch model to simplify the virtual reentry process of the power flow on the open fault is given respectively. Then, the calculation formula of power flow after fault identification is obtained. Then, according to the structure of line power flow, the algorithm of serious line search based on equivalent power flow and the algorithm of serious line search based on (FTIL) of power flow transfer intensity are proposed respectively. In the former, a new path search scheme is re-established by using equivalent power flow, and the path search is creatively extended to the case of multi-branch cutting. At the same time, the closed loop search strategy combined with path expansion and correction is adopted to avoid leakage. The latter uses FTIL to define the generalized power flow transfer serious area, which simplifies the distribution of multi-branch power flow transfer. And based on the breadth-first search (BFS) algorithm to define the region. By introducing FTIL as an heuristic term into the termination condition of BFS, the node can expand to avoid the smaller area of FTIL automatically, and improve the efficiency of searching serious circuit. A load reduction scheme based on virtual control unit (VCU) and heuristic search is proposed to solve the problem of line overload. Firstly, the network is reduced by the concentric relaxation principle, and the equipment and components that participate in the adjustment process are selected first. Secondly, the concept of virtual control unit is introduced to effectively identify the difference of load reduction effect between overload lines. Improve the resolution of traditional sensitivity algorithm. Then the heuristic search method of the optimal controllable unit, the calculation method of the optimal control unit's adjustment quantity and the control flow are put forward in combination with the constant cutting machine and the load control strategy. Finally, the cycle adjustment is adopted to adjust to the optimal load reduction direction until the overload is eliminated, and the physical meaning is clear. The calculation of the optimal control point and the adjustment amount is simple and fast, and the overloading is fed back at the end of each adjustment to realize the closed-loop control. Finally, the IEEE standard test system is taken as an example to verify and analyze the proposed algorithm. The simulation results show that the proposed algorithm can achieve the desired results by extending the fault to multiple transmission lines and provides a more complete emergency control strategy for the prevention of blackout caused by power flow transfer. It further improves the safety and stability of the power grid.
【學(xué)位授予單位】：華北電力大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TM761;TM744

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 任建文;魏俊姣;谷雨峰;;基于多目標(biāo)粒子群優(yōu)化算法的連鎖跳閘預(yù)防控制[J];電力自動化設(shè)備;2016年07期

2 徐巖;郅靜;;基于功率靈敏度的線路過載劃區(qū)域緊急控制策略[J];電工技術(shù)學(xué)報;2015年15期

3 徐巖;郅靜;;基于圖論和電壓相角的潮流轉(zhuǎn)移危險線路快速搜索[J];華北電力大學(xué)學(xué)報(自然科學(xué)版);2015年04期

4 劉獻(xiàn)超;任建文;渠衛(wèi)東;;基于廣度優(yōu)先法的多支路連鎖切除潮流轉(zhuǎn)移快速搜索算法[J];電力系統(tǒng)自動化;2015年13期

5 任建文;魏俊姣;;電力系統(tǒng)脆弱線路的識別及其輸電斷面搜索[J];電力自動化設(shè)備;2015年07期

6 任建文;魏俊姣;;基于GN分區(qū)的輸電斷面快速搜索[J];現(xiàn)代電力;2015年03期

7 陳曉玲;楊軍;羅超;孫元章;劉明松;湯涌;;一種大電網(wǎng)潮流轉(zhuǎn)移路徑快速搜索方法[J];電網(wǎng)技術(shù);2015年04期

8 林濟(jì)鏗;楊添剴;胡世俊;劉輝;袁啟海;林昌年;;基于模糊聚類和最短路徑的關(guān)鍵輸電斷面確定新方法[J];電力系統(tǒng)自動化;2015年05期

9 聶宏展;袁曉丹;張會強(qiáng);王菲;;基于多支路開斷和關(guān)鍵支路集的快速潮流轉(zhuǎn)移識別[J];電力系統(tǒng)保護(hù)與控制;2014年17期

10 苗世洪;馬帥;尚亞男;姜臻;侯俊賢;于之虹;;基于割點(diǎn)和路徑搜索的輸電斷面快速識別方法[J];電力系統(tǒng)自動化;2014年02期

，

本文編號：2267021