terminate one kind of automated protection which these events develop, the relay protection equipment can monitor the electrical equipment the normal work situation, and sends out the prompt signal differently according to the normal work situation and the equipment movement maintenance condition, in order to the attendant carries on prompt processing, either carries on the adjustment automatically by the protective device, either continues these to move possibly can cause the accident electrical equipment to excise.Response normal work situation relay protection equipment common belt certain time-lag action. The relay protection principle of work mainly the electrical power system the part the short circuit or the unusual situation the electrical quantity (electric current, voltage, power, frequency and so on) change as well as in transformer fuel tank when breakdown occurs the massive gas and the oil stream speed increase or the flowing tubing .The electrical power system request provides the safekeeping of security for it to continue the electricity installment to to be supposed to move time the body should act reliably.Should not when the movement should reliable not act.The reliability is to the relay protection installment performance most basic request.

(2) selectivity. The selectivity is refers first by the breakdown equipment logical 'OR' circuit itself protection excision breakdown, when the breakdown equipment logical 'OR' circuit itself protection or the circuit breaker resist moves, only then allows by the neighboring equipment to protect, the line protection or the circuit breaker malfunction protection excision breakdown.In order to guarantee the coordinate request protection and the identical protection the ordinary circumstances.

(3) sensitivity. The sensitivity is refers when the equipment logical 'OR' circuit occurs by the extent of protection in the metallicity short circuit, the protective device should smallest sensitivity coefficient in the regulations.Selectivity and sensitive request, through relay protection installation realization.

(4) speed. The speed is refers to the protective device to be supposed to excise the short circuit breakdown as soon as possible, its date enhances the system stability, reduces the breakdown equipment and the line damage degree, reduces the breakdown to affect the scope, enhances automatic switches on again with the emergency power supply or the emergency apparatus automatic investment effect and so on.

Third, relay protection in 11OKV power supply system Chen Ai function

1. The guarantee continues the electricity system the reliability is plays the relay protection installment role the premise. Continues the electricity system the reliability is plays the relay protection installment role the premise.Generally speaking the relay protection reliability mainly by the disposition reasonable, the quality and the technical performance fine relay protection installment as well as the normal movement maintenance and the management guaranteed.

2. Relay protection in electrical power system safe operation function. The relay protection mainly the electrical power system safe operation function:

(1) safeguard electrical power system security.When is protected when the electrical power system part breaks down, should rapidly accurately for be separated from the breakdown

part recent circuit breaker by this part relay protection equipment to send out the trip order, causes the breakdown part to interrupt promptly from the electrical power system, by maximum limit reduces to the electrical power system part itself damage, reduces to the electrical power system safe power supply influence, and satisfies the electrical power system certain specific requests (for example maintenance electrical power system transition condition stable and so on).

（2）pair of electrical power system normal work carries on the prompt.Responded the electrical equipment the normal work situation, (whether there is and different e.g. frequent attendant) does send out the signal according to the normal work situation and the equipment movement maintenance condition, in order to the attendant carries on processing, either carries on the adjustment automatically by the equipment, either continues these to move can cause the accident electrical equipment to excise.Response normal work situation relay protection installment permission belt certain time-lag action.

(3) pair of electrical power system movement carries on the monitoring.The relay protection is not merely an accident processing and the response installment, simultaneously also is monitors the electrical power system normal operation the installment.

The relay protection is the electrical power system safe normal operation important safeguard, at present oneself after obtained the widespread application, along with the science and technology unceasing progress, the relay protection technology presents day by day to the microcomputer, the network, the intellectualization, protects, the control, the survey and the data communication integration development tendency.

110KV供电系统继电保护作用浅析

电力系统的安全性和可靠性不仅关系到电力系统本身的运行，同样关系到送电范围内的厂矿、企业、居民能否正常用电。同时由于电力系统具有较强的连通性，电力系统内部的任何一个障碍都可能影响到整个系统的正常运行，因而我们必须切实做好供电系统的继电保护问题。 一、 11OKV 供电系统

一般来说电力系统包括发电、变电、输电、配电和用电等五个环节，五个环节之间相互制约、相互合作共同促成了电力系统的稳定。但事实上，由于这五个环节不总是在同一地点、同一时间完成的，输电要跨越辽阔的地区，同时电力系统要与不间的设备进行连接，从而增强了其运行环境的复杂性，导致电力系统的零故障率难以保证。110Kv供电系统是整个电力系统中的重要组成部分，其能否安全、稳定、可靠的运行，不仅关系到系统自身的运行质量，而且关系到其送电范围内广大的用户能否正常及时的用电，其对送电范围内经济的正常发展和社会的稳定担当着重要的能源保障任务。因此110KV供电系统的设计和运行管理必须全面遵守国家的有关标准和规范，以及相关地区的具体规范标准。110Kv供电系统中包含着一次系统和二次系统。二次系统相对于一次系统较为复杂，犯次系统包括了继电保护装置、自动装置和二次回路。继电保护装置是在供电系统中用来对一次系统进行监视、测量、控制和保护，由继电器来组成的一套专门的自动装置。合理的继电保护装置的正确设置对确保110Kv供电系统的正常运行有着积极的作用。 二、 继电保护的撅念及相关原理

电力系统的飞速发展对继电保护不断提出新的要求，电子技术、计算机技术与通信技术的飞速发展又为继电保护技术的发展不断地注入了新的活力。

继电保护是指当电力系统中的电力元件(如发电机、线路等)或电力系统本身发生了故障危及电力系统安全运行时，能够向值班人员及时发出警告信号，或者直接向所控制的断路器发出跳闸命令以终止这些事件发展的一种自动化保护，继电保护装置能够监控电气设备的不正常工作情况，并根据不正常工作情况和设备运行维护条件的不同发出提示信号，以便值班人员进行及时处理，或由保护装置自动进行调整，或将那些继续运行可能会引起事故的电气设备予以切除。反应不正常工作情况的继电保护装置一般带一定的延时动作。

继电保护的工作原理主要是利用了电力系统中元件发生短路或异常情况时电气量(电流、电压、功率、频率等)的变化以及变压器油箱内故障时发生的大量瓦斯和油流速度的增大或油压强度的增高等条件。电力系统要求为其提供安全保护的继电装置具备以下性能:

(1) 可靠性 。 可靠性是指保护该动体时应可靠动作。不该动作时应可靠不动作。可靠性是对继电保护装置性能的最根本的要求。

〔2) 选择性 。 选择性是指首先由故障设备或线路本身的保护切除故障，当故障设备或线路本身的保护或断路器拒动时，才允许由相邻设备保护、线路保护或断路器失灵保护切除故障。为保证对相邻设备和线路有配合要求的保护和同一保护内有配合要求的两元件(如启动与跳闸元件或闭锁与动作元件)的选择性，其灵敏系数及动作时间，在一般情况下应相互配合。

(3) 灵敏性 。 灵敏性是指在设备或线路的被保护范围内发生金属性短路时，保护装置应具有必要的灵敏系数，各类保护的最小灵敏系数在规程中有具体规定。选择性和灵敏性的要求，通过继电保护的整定实现。

(4) 速动性 。 速动性是指保护装置应尽快地切除短路故障，其日的是提高系统稳定性，减轻故障设备和线路的损坏程度，缩小故障波及范围，提高自动重合闸和备用电源或备用设备自动投入的效果等。

三、 继电保护在11OKV供电系统障碍中的作用

1. 保证继电系统的可靠性是发挥继电保护装置作用的前提。

继电系统的可靠性是发挥继电保护装置作用的前提。一般来说继电保护的可靠性主要由配置合理、质量和技术性能优良的继电保护装置以及正常的运行维护和管理来保证。 2. 继电保护在电力系统安全运行中的作用。

继电保护在电力系统安全运行中的作用主要有以下两点:

(1) 保障电力系统的安全性。当被保护的电力系统元件发生故障时，应该由该元件的继电保护装置迅速准确地给脱离故障元件最近的断路器发出跳闸命令，使故障元件及时从电力系统中断开，以最大限度地减少对电力系统元件本身的损坏，降低对电力系统安全供电的影响，并满足电力系统的某些特定要求(如保持电力系统的暂态稳定性等)。

(2) 对电力系统的不正常工作进行提示。反应电气设备的不正常工作情况，并根据不正常工作情况和设备运行维护条件的不同(例如有无经常值班人员)发出信号，以便值班人员进行处理，或由装置自动地进行调整，或将那些继续运行会引起事故的电气设备予以切除。反应不正常工作情况的继电保护装置允许带一定的延时动作。

(3) 对电力系统的运行进行监控。继电保护不仅仅是一个事故处理与反应装置，同时也是监控电力系统正常运行的装置。

继电保护是电力系统安全正常运行的重要保障，目前己经得到了广泛的应用，随着科学技术的不断进步，继电保护技术日益呈现出向微机化，网络化，智能化，保护、控制、测量和数据通信一

体化发展的趋势。

致 谢