本文選題：火電直流孤島運(yùn)行　切入點(diǎn)：頻率控制　出處：《華北電力大學(xué)(北京)》2017年博士論文　論文類型：學(xué)位論文

【摘要】：高壓直流輸電(HVDC)因其經(jīng)濟(jì)性和快速靈活、高度可控的特點(diǎn),在大型能源基地向負(fù)荷中心的遠(yuǎn)距離輸電中應(yīng)用非常廣泛。若高壓直流輸電運(yùn)行時(shí)的送端系統(tǒng)主要由火電機(jī)組(群)組成而與交流主網(wǎng)無(wú)電氣聯(lián)系,則稱為火電直流孤島運(yùn)行,該系統(tǒng)則稱為直流孤島送出系統(tǒng)。直流孤島送出系統(tǒng)有效短路比和轉(zhuǎn)動(dòng)慣量小,系統(tǒng)承受擾動(dòng)能力較弱,存在著頻率穩(wěn)定、過(guò)電壓、次同步振蕩等一系列技術(shù)問(wèn)題,造成機(jī)組全停和直流閉鎖的可能性大大增加,給含大量熱力生產(chǎn)過(guò)程的火電直流孤島運(yùn)行穩(wěn)定控制、系統(tǒng)和設(shè)備安全及工程決策帶來(lái)了巨大的困難。隨著我國(guó)國(guó)內(nèi)大型火電基地的集中開(kāi)發(fā)和遠(yuǎn)距離外送以及國(guó)際電力能源的引進(jìn),受當(dāng)?shù)仉娋W(wǎng)規(guī)模、系統(tǒng)接入條件等因素限制,火電直流孤島系統(tǒng)研究和試驗(yàn)的現(xiàn)實(shí)意義和重要性日益凸顯,而國(guó)內(nèi)外尚沒(méi)有火電直流孤島系統(tǒng)的運(yùn)行經(jīng)驗(yàn)。以往對(duì)于直流孤島系統(tǒng)頻率穩(wěn)定的研究主要依賴于接入實(shí)際直流控制保護(hù)系統(tǒng)的實(shí)時(shí)仿真或采用詳細(xì)直流控制保護(hù)電磁暫態(tài)模型的離線仿真,采用窮舉法進(jìn)行交直流故障研究從而得到該系統(tǒng)的實(shí)際控制效果,采用試探法進(jìn)行控制系統(tǒng)參數(shù)的優(yōu)化,因而存在耗時(shí)長(zhǎng)、投入成本高的問(wèn)題,對(duì)于控制穩(wěn)定性結(jié)論和認(rèn)識(shí)存在盲區(qū),無(wú)法從定性和定量?jī)煞矫嬲嬲笇?dǎo)工程實(shí)踐。本文首先從基本物理概念出發(fā),揭示了火電直流孤島系統(tǒng)頻率特性問(wèn)題的物理本質(zhì),對(duì)直流輸電系統(tǒng)、汽輪機(jī)組、伺服系統(tǒng)等分別進(jìn)行了簡(jiǎn)化建模,降低了火電直流孤島系頻率控制閉環(huán)系統(tǒng)的階數(shù),從而建立了等效的與實(shí)際系統(tǒng)特性一致的火電直流孤島系統(tǒng)傳遞函數(shù)模型,針對(duì)火電機(jī)組一次調(diào)頻、直流附加控制等不同控制策略和參數(shù)配合,基于根軌跡分析進(jìn)行了火電直流孤島系統(tǒng)的頻率穩(wěn)定性研究及優(yōu)化控制系統(tǒng)參數(shù),揭示孤島系統(tǒng)頻率穩(wěn)定性機(jī)理�？紤]到電力系統(tǒng)和設(shè)備的安全性,實(shí)際運(yùn)行中的火電機(jī)組和直流系統(tǒng)的控制復(fù)雜性,本文以±500kV呼遼直流輸電工程孤島送出系統(tǒng)為例,建立了反映包括送端系統(tǒng)各發(fā)電機(jī)組、交流線路、直流系統(tǒng)等實(shí)際特性的詳細(xì)準(zhǔn)確電磁暫態(tài)仿真模型,通過(guò)交直流故障仿真分析,從三個(gè)方面研究揭示火電直流孤島系統(tǒng)運(yùn)行的關(guān)鍵性問(wèn)題,一是穩(wěn)態(tài)或正常操作時(shí)滿足電力系統(tǒng)穩(wěn)態(tài)頻率控制指標(biāo)的要求,二是N-1故障等無(wú)安控措施下的火電直流孤島系統(tǒng)恢復(fù)能力及頻率波動(dòng)范圍滿足機(jī)組設(shè)備等頻率控制要求,三是嚴(yán)重故障下配合安控措施的孤島系統(tǒng)頻率穩(wěn)定性問(wèn)題,并給出了不同控制參數(shù)及配合下的火電直流孤島系統(tǒng)運(yùn)行條件和運(yùn)行控制策略。針對(duì)直流輸電工程建設(shè)發(fā)展過(guò)程產(chǎn)生的單臺(tái)火電機(jī)組與直流系統(tǒng)直接配合啟動(dòng)的需求,考慮汽輪機(jī)組、直流系統(tǒng)等各方面設(shè)備的能力和安全問(wèn)題,研究了二者配合啟動(dòng)過(guò)程中由于響應(yīng)特性不同而產(chǎn)生的頻率穩(wěn)定性問(wèn)題。由于火電機(jī)組并網(wǎng)運(yùn)行時(shí)鍋爐及汽輪機(jī)的限制,很難在并網(wǎng)時(shí)初負(fù)荷從零直接提升配合啟動(dòng)直流,因此論文從兩方面考慮,綜合解決直流啟動(dòng)對(duì)火電機(jī)組并網(wǎng)初負(fù)荷的要求:一是采取措施進(jìn)一步降低直流啟動(dòng)功率,另一方面提高機(jī)組帶初負(fù)荷的能力,并對(duì)不同汽輪機(jī)組控制器的啟動(dòng)效果、機(jī)組與直流配合時(shí)間等方面進(jìn)行了仿真論證。本文提出的研究方法為后續(xù)直流工程建設(shè)和運(yùn)行中可能出現(xiàn)的孤島運(yùn)行方式的選擇奠定了理論基礎(chǔ),為未來(lái)大型火電基地的集中開(kāi)發(fā)和遠(yuǎn)距離外送提供了技術(shù)依據(jù)。
[Abstract]:High voltage direct current transmission (HVDC) because of its economy and fast and flexible, highly controllable, applied to long distance transmission load center in a large energy base in a very wide range. If the end system send HVDC when operating mainly by thermal power units (Group) and no electrical connection and the communication network is called power DC islanding operation, the system is called DC system. Effective short Island sent DC Island sending system ratio and small inertia, system under disturbance ability is weak, there is a stable frequency, voltage, a series of technical problems of subsynchronous oscillation, resulting in the possibility of unit full stop and DC blocking DC power to greatly increase the island contains a large number of thermal stable operation control of the production process, decision-making system and the safety of the equipment and engineering has brought great difficulties. With the focus on the development of the domestic large-scale thermal power base in China and far From the delivery and the introduction of international power, by the local power grid scale, restricting system access conditions and other factors, practical significance and importance of the research and test of DC system of power island has become increasingly prominent, and there is no operating experience in power system. The isolated DC DC frequency stabilization for the study of the islanding system mainly depends on the line the simulation of real-time simulation of actual HVDC control and protection system access or use with DC control protection electromagnetic transient model, using exhaustive method to study fault in DC to obtain the actual effect of this system, optimize the parameters of control system using heuristics, which are time-consuming, high cost problems, for the control of stability and conclusion unable to recognize the existence of blind spots, from two aspects of qualitative and quantitative real engineering practice. This paper begins from the basic physical concepts Starting, reveals the physical essence of the frequency characteristics of DC power system islanding problem, the DC transmission system, steam turbine, servo system were simplified modeling, reduce the power system frequency control DC order Island closed loop system, and established the equivalent with the actual system characteristics consistent power DC islanding system transfer function model for a time, frequency and power units, with the additional DC control of different control strategies and parameters, root locus analysis and optimization are studied based on the frequency stability of power system islanding DC control system parameters, to reveal the frequency stability of islanding system mechanism. Considering the safety of power system and equipment, control the complexity of the actual operation of the thermal power unit and DC system, taking 500kV + Hulunbeier Liaoning HVDC Island sent system as an example, including the sending end system is established to reflect the All the generating units, the AC line, with accurate electromagnetic transient simulation model of the actual characteristics of DC system, the DC fault simulation analysis, from three aspects of key problems of power system operation of DC Island, is a power system to meet the requirements of steady steady frequency control or normal operation, the two is N-1 no fault in power system security control measures under DC Island recovery and frequency fluctuation range to meet the unit frequency control requirements, the three is the frequency stability problem with islanding system under severe faults control measures, and gives the power control system of DC island operation conditions and operation strategy of different control parameters and with single power. The unit and the DC system for DC transmission project development process directly with the needs of start, consider the steam turbine unit, DC system The ability and safety problems and other aspects of equipment, on the two with the start process due to the frequency stability problem caused by different response characteristics. Because of boiler and turbine thermal power units connected to the limit, is very difficult in the network initial load from zero start with DC Direct promotion, so this paper in two aspects, comprehensive to solve the requirements of DC starting load thermal power grid at the beginning: one is to take measures to further reduce the DC power to start, on the other hand, improve the unit load capacity with initial, and the controller of different turbine starting unit and DC effect, with time and other aspects of the simulation verification. The research method for islanding operation possible follow-up HVDC project in construction and operation choice laid a theoretical foundation for the future focus on the development of large thermal power bases and distance from outside The delivery provides a technical basis.

【學(xué)位授予單位】：華北電力大學(xué)(北京)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2017
【分類號(hào)】：TM712;TM732

【相似文獻(xiàn)】

相關(guān)博士學(xué)位論文 前4條

1 王華偉;火電直流孤島系統(tǒng)頻率控制策略研究[D];華北電力大學(xué)(北京);2017年

2 馬世乾;配電網(wǎng)智能孤島劃分與隨機(jī)拓?fù)渖蒣D];天津大學(xué);2016年

3 DO THANH HIEU（杜成孝）;基于小波包變換的光伏并網(wǎng)逆變器孤島檢測(cè)方法研究[D];合肥工業(yè)大學(xué);2016年

4 貝太周;分布式光伏并網(wǎng)系統(tǒng)關(guān)鍵問(wèn)題研究[D];天津大學(xué);2016年

相關(guān)碩士學(xué)位論文 前3條

1 王淼;風(fēng)電場(chǎng)防孤島保護(hù)策略研究[D];中國(guó)電力科學(xué)研究院;2017年

2 陳嘉;含分布式電源的配電網(wǎng)孤島搜索與儲(chǔ)能配置問(wèn)題研究[D];天津大學(xué);2016年

3 張曉倩;光伏并網(wǎng)發(fā)電系統(tǒng)中基于狀態(tài)估計(jì)的MPPT及孤島檢測(cè)方法研究[D];南昌大學(xué);2017年

，

本文編號(hào)：1649434