地区降压变电所二次部分设计低频减载仿真.docVIP

地区降压变电所二次部分设计低频减载仿真 摘 要 本文针对变电所主变压器的二次部分设计，以数字式继电保护为基本出发点进行以下了内容的设计。根据电力系统与变电所主变的特点，作者对短路电流进行计算，选择合适型号的保护装置，从而进行各种整定计算，并分析计算结果的合理性以给出继电保护装置的参数与定值。使得主变保护选择性、灵敏性和可靠性满足 is aimed at the main transformer of substation of the design of second part, and had done the following design which is based on the digital protection as a starting point. According to the power system and the main transformer of substation features, the author made the calculation of short-circuit current, chose a suitable model of the protection device ,thus made the calculation for various setting, and analyzed weather the calculation results was reasonable so that to confirm the parameters and values for the device of relaying protection. To make the selectivity, sensitivity and reliability of relaying protection of main transformer meet the requirements, so that the relaying protection device could make full of its effects and guarantees the stability of the power system operation. Using matlab software for UFLS(Under-Frequency Load Shedding) simulation modeling, the model made up of discrete 3-phase PLL(phase Locked Loop) block measurement block, relay block, three-phase circuit breaker block etc, had realized the simulation of the process of shedding the corresponding load automatically when the frequency fell to a certain value . The author had analyzed changes in the extent and trait of each electric element of this model during the process of simulation and summarized the characteristics of each electricity element, thus to make sure the simulation is feasible and correct. Key Words substation, the design of second part, matlab, Under-Frequency Load Shedding 目 录 摘 要 I Abstract II 1 绪论 - 1 - 2 220kV降压变电所的基本知识 - 2 - 2.1?变电所的作用 - 2 - 2.2 电气主接线的设计 - 2 - 2.3 总结 - 3 - 3 变压器运行的安全与继电保护 - 4 - 3.1 变压器运行的安全 - 4 - 3.2继电保护的基本知识 - 4 - 3.3变压器的继电保护装置运行整定规程 - 5 - 4 220kV变电所主变二次设计 - 6 - 4.1 变电所一次接线及系统运行方式的说明 - 6 - 4.2 短路阻抗与短路电流的计算 - 7 - 4.3电力变压器保护的配置 - 9 - 4.4电力变压器保护整定计算 - 13 - 5 低频减载的matlab软件仿真 - 2