【作者】 张震；

【导师】 王伟杰；

【作者基本信息】 哈尔滨工业大学 ， 机械工程（专业学位）， 2019， 硕士

【摘要】 电力系统是一个国家经济发展的根本,同时,电力系统的安全稳定情况更是衡量一个国家综合国力的重要标准,世界各国无数个电力事故的惨痛教训告诉我们,电力系统一旦遭到严重破坏,其带来的巨大经济损失和严重后果都是难以预估的。当今社会随着各行各业用电量的持续增加,电网的开发利用也变得商业化、多元化,由此带来的电力系统安稳问题也逐年呈上升趋势。这一切都表明更加深入的探讨电网安稳问题的机理、不断开发更加有效的电网安稳分析方法、总结出既经济又适用的电网控制方案,这一切将成为当今每一个电力人面临的重要课题。本课题以鸡西热电厂扩建项目接入方案为切入点,对接入电网的安全稳定性进行分析。鸡西供电区共有省调统调电厂6座,总装机容量1270.4MW,其中火电厂2座,装机容量850MW;风电场4座,装机容量402.4MW。由于该区域供热能力不足,加之供热负荷不断增加,为解决这一问题急需增设供热机组,新机组的增加势必会给原有薄弱的电网带来新的挑战。鸡西热电厂扩建项目的并网运行将会影响接入电网的电压质量和潮流分布,甚至会对鸡西地区整体电网的安全性产生巨大影响。因此,开展鸡西热电厂扩建项目对接入电网安全性分析具有重要的研究意义和工程价值。本文进行了全省、鸡西地区电力电量平衡分析及电网现状分析。从改变地区供热结构、提高地区供热效率和供电可靠性的角度,阐述了鸡西热电项目建设的必要性。然后,对鸡西热电厂扩建项目接入电网后的静态安全稳定进行研究分析,首先根据实际情况设定潮流计算的基本条件,并对正常方式和检修方式下N-1故障进行模拟计算分析,提出了鸡西地区电网静态的安全隐患,给出了具体的解决措施。并对结果进行校验分析,证实解决措施的简单性和可靠性,为该区域电网类似故障再次发生时如何处理提供参考和依据。最后对鸡西热电厂扩建项目接入电网后的暂态安全稳定进行研究分析,首先给出了电网暂态分析中常用的几种数学模型,并对常见的运行方式和故障进行了设定,通过对单回线路发生故障、主变发生故障以及220kV双母线一回检修另一回故障切除等情况进行潮流计算,分析鸡西电网在面临大干扰或遭遇复杂故障时的抵抗能力,对研究中发现的问题分别给出了相应的有效措施。分析结果表明,发电机组自身的励磁调节等方式能够保证系统在出现轻微或者一般性故障时的暂态稳定,为该区域电网类似故障再次发生时如何处理提供参考和依据。更多还原

【Abstract】 The power system is the foundation of a country’s economic development,and the security and stability of the power system is an important criterion to measure a country’s comprehensive national strength.The tragic lessons of countless power accidents around the world tell us that once the power system is seriously damaged,the huge economic losses and serious consequences are unpredictable.With the continuous increase of electricity consumption in all walks of life in today’s society,the development and utilization of power grids has become commercialized and diversified,and the resulting problems of power system’s stability are also on the rise year by year.All indicates that more in-depth discussion of the mechanism of power grid’s stability,continuous development of analysis methods of more effective power grid’s stability,and summing up both economic and applicable power grid’s control schemes,all of which will become an important issue that every power user needs to face nowadays.On the entry point of grid connection scheme of Jixi Thermal Power Plant’s expansion project,the security and stability of access to grid are analyzed in this paper.There are 6 provincial power plants in Jixi Power Supply Zone,with a total installed capacity of 1270.4 MW,including 2 thermal power plants with installed capacity of 850 MW and 4 wind farms with installed capacity of 402.4 MW.Because of insufficient heating capacity and increasing heating load in this region,it is urgent to add heating units to solve this problem.The increase of new units will inevitably bring new challenges to the original weak power grid.The grid-connected operation of Jixi Thermal Power Plant’s expansion project will affect voltage quality and power flow distribution of the grid,and even have a huge impact on the security of the overall grid in Jixi.Therefore,it is of important research significance and engineering value to analyze the security of access to grid of Jixi Thermal Power Plant’s expansion project.This paper analyzes current situation of power balance and power grid in Jixi and the whole province.From the view of changing district heating structure,improving district heating efficiency and reliability of power supply,this paper expounds the necessity of the construc tion of Jixi Thermal Power Project,and puts forward some solutions to the problems that may arise in the process of access to power grid.Then,this paper do researches and analyses on the static security and stability of Jixi Thermal Power Plant after its expansion project is connected to the power grid.Firstly,the basic conditions of power flow calculation are set according to actual situation,and the analog computation and analyses on faults of "N-1" under normal mode and maintenance mode are carried out.The potential safety hazard of static security of Jixi power grid are put forward,and the specific solutions are given.The results are checked and analyzed to verify the simplicity and reliability of the solutions.Lastly,the transient safety and stability of Jixi Thermal Power Plant after its expansion project is connected to the power grid are studied and analyzed in this paper.Firstly,several mathematical models commonly used in the transient analysis of Hei Longjiang power grid are given,and the common operation modes and faults are set.Through the power flow calculation on the fault of single circuit line,main transformer and 220 kV double busbar’s primary circuit repair and clearing out of secondary circuit‘s fault,the resistance of Jixi Power Grid in the face of large disturbances or complex faults are analyzed,and the corresponding effective measures are given separately for the problems found in the study.The results of analysis show that the excitation regulation of the generator unit can ensure the transient stability of system in the case of slight or general faults,and provide reference and basis for how to deal with similar faults in the regional power grid when they occur again.更多还原