500kV SICSFCL对继电保护正确动作的影响研究

【作者】 王龙；

【导师】 束洪春； 曹昆南；

【作者基本信息】 昆明理工大学 ， 电气工程， 2013， 硕士

【摘要】 随着各用电户对供电质量的要求越来越高,特别是部分电子和信息产品设备对电能质量要求特别高,即要保证连续不间断的供电,又要维持电压、频率基本恒定并降低谐波水平等。针对电网短路电流的不断增大,为保证电力系统安全可靠地稳定运行,必须采取限流措施,以保证电力断路器能够有效切断故障,因此超导限流器的研发和应用是非常迫切和必要的!超导限流器是非线性、时变元件,在电力系统有无故障时表现得特性明显不同,不同故障电流阻抗特性也有较大差异。超导限流器的使用,对不同继电保护的正确动作有不同影响。本文首先介绍了几种常见的超导电力装置。通过对超导电力技术基础知识的介绍,简单概括了几种常见的超导限流器原理和关键技术以及优缺点,重点介绍了饱和铁芯性超导限流器(SICSFCL)的工作原理。并基于系统应用基础,对普吉变电站超导限流器运行状况做了简单介绍,对饱和铁芯型超导限流器关键技术做了分析。其次本文分析了饱和铁心型超导限流器(SICSFCL)工作运行区间和阻抗特性,并在此基础上用PSCAD软件和Ansoft软件开展了饱和铁心型超导限流器的电磁建模与系统仿真分析。通过对SICSFCL的建模仿真与数据处理后的研究,验证了饱和铁心型超导限流器(SICSFCL)的工作原理、工作区间和阻抗特性,最后还对两种建模方法做了对比分析。最后本文对短路电流的分类和特性做了研究,对投入SICSFCL和未投入SICSFCL时短路故障时阻抗变化做了对比分析,对于不同状况下的短路阻抗和电压变化做了定性分析。论文对500kV输电线路继电保护方法作了介绍,并分析了SICSFCL投入前后对距离保护和差动保护正确动作的影响,并提出了相关整定方法。更多还原

【Abstract】 As customers demand on the power quality for electricity, especially on parts of the electronic and information products equipment power quality, which is not only to ensure uninterrupted power supply, but also to maintain the voltage, frequency substantially constant and reduce harmonic levels. Therefore, in order to ensure that the system can operate safely, reliably and stably, it is imperative to take effective measures to limit the short circuit current such that the circuit breaker can cut off the fault current effectively. Thus, the development and application of the superconducting current limiter is urgent and necessary. Superconducting current limiter is a nonlinear, time-varying element, and its performance characteristic shows significantly different whether the failure of the power system, different fault current operating characteristics are also quite different. Moreover such electrical equipments in different installation positions have a different impact on the relay protection.In this paper, we firstly introduce the common types of superconducting electrical installations. In the next chapter, we illustrate the basics knowledge of superconducting power technology, some common superconducting current limiter principle and key technologies as well as their advantages and disadvantages. And we introduce several common principle of centralized relay of500kV systems based on the application infrastructure.We deeply analyze the working principle of the saturable core superconducting current limiter (SICSFCL) and focuse on the work running range and impedance characteristics of SICSFCL. Furthermore based on the PSCAD software and Ansoft software, we carry out electromagnetic modeling and system simulation for saturation core superconducting current limiter. We verify the working principle, working range and feature of the saturable core superconducting current limiter (SICSFCL) by the SICSFCL modeling simulation and analysis, and finally analyze the two modeling comparatively.Finally, we describe the current characteristics of various short-circuit situations for power systems, and analyze the performance of SICSFCL and the traditional split-limiting reactor comparatively. Subsequently, we analyze the short-circuit fault impedance changes whether using the SICSFCL or not, And furthermore, we have qualitative analysis of the short-circuit impedance and voltage variations under different conditions, and analyze the impact of the relay protection strategy before and after the SICSFCL invested.更多还原