摘要:电能是现代社会中最重要、也是最方便的能源。现代电力系统是一个由电能生产、输送、分配和用电环节组成的大系统,如何正确运用继电保护技术来遏制电气故障,提高电力系统的运行效率及运行质量已成为迫切需要解决的技术问题!电能经过变压器和不同电压等级的输电线路输送并被分配给用户,再通过各种用电设备转换成适合用户需要的其他形式的能量。在输送电能的过程中,电力系统希望线路有比较好的可靠性,因此在电力系统受到外界干扰时,保护线路的各种继电装置应该有比较可靠的、及时的保护动作,从而切断故障点极大限度的降低电力系统供电范围。
对供电系统最大的威胁就是短路故障,而输电线路又是最易出现短路故障的环节,因此必须采取措施来重点保护它。继电保护是线路保护的最常用手段,当线路出现故障时,能快速的,有选择性的切除故障,防止事故的进一步恶化。
本次设计的题目是35kv双侧电源输电线路的设计及继电保护。根据该电网的结构、电压等级、线路长度、运行方式以及可靠性质的要求,设计35KV的输电线路及合适的继电保护。主要包括内容有:输电线路导线选择及短路计算;线路主保护、后备保护的选择与整定;变压器主、后备保护的选择;线路三相一次重合闸及备用电源自动投入。电网继电保护定值的整定计算工作是保证电力系统安全运行的必要条件。
关键词:35KV线;路继电保护;整定计算
Abstract:The electricity is the most important in the modern society,and also is the most convenient energy.Modern power system is by electric energy production, transmission, distribution and power consumption of large system of the link, how to correctly apply the relay protection technology to contain electrical fault, improve the efficiency of electric power system and the operation quality has become the urgent need to solve technical problems! Power after transformer and different voltage grade of transmission lines conveying and was assigned to the user, and then through the various electrical equipment for users need to convert the other forms of energy. In the process of conveying electrical energy, electric power system hope that line of a good reliability, so in electric power system is outside interference, protection of circuit relay device should have more reliable and timely protection movement, thereby cutting off a breakdown maximum limit reducing power systems power supply range.
For power supply system of the biggest threat is short circuit fault, and transmission line is the most easy appear short-circuit fault link, therefore measures must be taken to key to protect it. The relay protection is line protection the most commonly used method, when lines malfunction, can quickly,selective remoal of the fault, prevent accident of further deterioration.
The design on the topic of 35 KV bilateral power transmission line design and relay protection. According to the power grid structure, voltage grade, line length, operation mode and reliability quality requirements, design of 35 KV transmission lines and suitable relay protection. Mainly includes the contents: electrical substation equipment analysis; Short-circuit current calculation; Line to the Lord, and the choice of backup protection; Three-phase a reclose; Lines and the transformer lightning protection. Power grid relay protection setting value of setting calculation work is to ensure the safe operation of the power system the necessary condition.
Key words: 35KV line; Relay protection ; Setting calculation