An over view of electrical power transmission line protection systems

Electric power transmission systems are the means of transmitting power from a generating source to various load centers where the power is being used. Generating stations generate electrical power. These generating stations are not necessarily situated where the majority of the power is being consumed. Since distance is not the only factor that determines the ideal location for a generating station, the place where the power is generated may be quite far away from where it is used. Land further from the load center which is generally a high-density central location can be much cheaper per square meter and governments may not want such loud and/or polluting stations close to residential areas. Hence power transmission systems are crucial to the supply of power in electrical networks. Overall, electrical supply systems are the network through which consumers of electricity receive power from a generation source such as a thermal power station. Power transmission systems including short transmission lines, medium transmission lines, and long transmission lines transport the power from the generation source and into a power distribution system. These distribution systems provide electricity to individual consumer premises. Power transmission line protection systems are one of the most important system under electrical power system. Transmission system is a system which between the generation and the distribution centers. There are two main power transmission systems which use in electrical industry. Distance relays are use to protect transmission line and this are simple to apply. Advantage of the distance relays is they are high speed operation. In here we are plan to discuss on several factors which affect on protecting high voltage transmission lines.Synchronized wide area communication has become a mature technology, which makes the real-time interaction between the substations and the wide area protection and control system possible. However, the present protection and control system to handle this real-time data has been recognized to be deficient. This paper begins by reviewing the development history of power system protection, with special attention paid to the recent development in the field of wide-area and integrated protections, in order to look into the future development of protection and control systems. Then the concept of integrated wide area protection and control is introduced, where it can be shown that a hierarchical protection and control system provides the protection and control for wide area or regional power substations/plants and their associated power networks. The system is mainly divided into three levels: the local, the substation and plant, and the wide area and or regional. The integrated functions at each level are described in details with an aim to develop an optimal coordination mechanism between each level. The key element in the proposed system is the wide area real-time protection and control information platform, which not only enables the merger of three lines of defense for power system protection and control, but also provides a perfect tool for the application of cloud computing in substations and power networks.

کلیدواژه ها:

Electrical power ، Transition ، Control ، Protection