次同步谐振分析及控制策略研究

发布时间：2018-05-12 15:23

本文选题：次同步谐振 + 测试信号法　；参考：《华北电力大学》2017年硕士论文

【摘要】：由于能源结构调整的现实需求和我国能源“西产东用”的实际情况,必须发展“西电东送”和大电网互联系统。串补装置在远距离和大容量传输线路中的应用,有效的减少了线路的等效电抗便一定程度提高了电力系统的静稳极限和潮流传输能力。但伴随串联补偿设备的应用而引起的次同步谐振(Sub-synchronous Resonance;SSR)问题也日益凸显,尤其是其对发电机组的轴系损伤而大大的降低电力系统的稳定性,并对发电机组存在潜在危机。可见细致的研究次同步谐振的相关机理、分析测试方法、相关的阻尼控制措施以及工程应用实例,对于维持系统稳定以及抑制次同步谐振具有极高的应用价值。基于如此发展前景,本文对次同步问题进行分析,分类测试方法、提出抑制策略并结合工程进行研究,主要内容如下:(1)分析了测试信号法相关原理及该法的实现方案。首先分析电力系统的电气阻尼和机械阻尼的计算方法,进而分析其与系统次同步谐振的关系,利用此关联判断系统的稳定性;其次基于测试模型验证测试信号方法的有效性,即将该法的分析结果与时域仿真结果对比分析;最后基于无穷大系统的标准模型进行运行工况的分析验证,给出了一套适用于电力系统的次同步谐振分析的测试信号法应用方案。(2)提出了使用统一潮流控制器(Unified Power Flow Controller;UPFC)来解决系统的次同步谐振问题,并提出适用于工程的阻尼控制器设计方法。基于UPFC的运行原理,通过对UPFC的主要控制措施附加阻尼控制,来达到抑制次同步谐振目的来设计阻尼控制器。通过数学仿真模型和仿真结果可以发现,仅通过统一潮流控制器和固定的电容串联补偿并无法保证系统整体阻尼为正,则系统存在发生次同步谐振的风险。在此类分析的基础上对于主要控制附加UPFC阻尼控制,此时可提高系统阻尼,进而基于此设计阻尼控制器、结合算法给出参数的确定方案,最终结合模型加以验证分析。(3)研究了工程上利用其现场数据进行分析、装备相关阻尼控制器来提高系统阻尼,最终解决次同步谐振的问题。分析南京实际工程的运行环境及次同步谐振风险的现状,装备含UPFC的阻尼控制后,结合试验数据分析其对SSR的抑制效果。首先从硬件设备上分析次同步谐振的抑制效果,进而结合工程的实测数据和图形进行分析。目标是结合工程实际分析次同步的产生和抑制方案,提高阻尼并抑制系统次同步谐振。论文最终基于南京系统模型和实际工程数据分析了结合工程提高系统阻尼,抑制次同步谐振问题的可行性。
[Abstract]:Due to the actual demand of energy structure adjustment and the actual situation of "producing energy from west to east" in our country, it is necessary to develop "power transmission from west to east" and interconnection system of large power grid. The application of series compensator in long distance and large capacity transmission lines effectively reduces the equivalent reactance of the line and improves the static stability limit and power flow transmission ability of the power system to a certain extent. However, the sub-synchronous Resonance system (SSRs) problem caused by the application of series compensation equipment is becoming increasingly prominent, especially its damage to the shafting of the generator sets greatly reduces the stability of the power system, and there is a potential crisis to the generator sets. It can be seen that the detailed study of the mechanism of sub-synchronous resonance, the analysis of testing methods, the relevant damping control measures and engineering application examples have a high application value for maintaining the stability of the system and suppressing the sub-synchronous resonance. Based on this prospect, this paper analyzes the sub-synchronization problem, classifies the test methods, puts forward the suppression strategy and studies it in combination with engineering. The main contents are as follows: 1) the related principle of the test signal method and its implementation scheme are analyzed. First, the calculation method of electrical damping and mechanical damping of power system is analyzed, then the relation between the damping and the sub-synchronous resonance of the system is analyzed, and the stability of the system is judged by this correlation. Secondly, the validity of the test signal method is verified based on the test model. The results of this method are compared with the results of time domain simulation. Finally, based on the standard model of infinite bus system, the operating conditions are analyzed and verified. In this paper, a set of test signal method application scheme for subsynchronous resonance analysis of power system is presented. A unified power flow controller, Unified Power Flow Controller (UPFC), is proposed to solve the sub-synchronous resonance problem of the system. The design method of damping controller suitable for engineering is put forward. Based on the operation principle of UPFC, the damping controller is designed by adding damping control to the main control measures of UPFC. Through the mathematical simulation model and simulation results, it can be found that only through unified power flow controller and fixed capacitor series compensation and can not guarantee the overall damping of the system is positive, then the system has the risk of sub-synchronous resonance. On the basis of this kind of analysis, the damping of the system can be improved by adding UPFC damping control to the main control, and then the damping controller is designed based on this, and the parameter determination scheme is given in combination with the algorithm. Finally, the model is used to verify and analyze the system. Finally, the problem of sub-synchronous resonance is solved by using the field data to analyze the system, and the related damping controller is equipped to improve the damping of the system. This paper analyzes the running environment of Nanjing actual project and the present situation of the risk of sub-synchronous resonance. After equipped with damping control with UPFC, the restraining effect of SSR is analyzed by combining the test data. First, the suppression effect of subsynchronous resonance is analyzed from the hardware equipment, and then the measured data and graph of the project are analyzed. The aim of this paper is to analyze the generation and suppression scheme of subsynchronization based on engineering practice, to increase the damping and to suppress the sub-synchronous resonance of the system. Finally, based on Nanjing system model and practical engineering data, the feasibility of increasing system damping and suppressing sub-synchronous resonance is analyzed.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM712

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