Relay Protection Setting Technology And New Protection Methods Based On Multi-agent Research

The developments of both power system and electricity market ask for that the protective relaying can work more securely. Whether protective relaying can satisfy the needs is correlative with many factors, such as the amount of sample information, theory and criterion of protective relaying, and proper setting, et al. At present, current relaying and distance relaying are applied widely as transmission protection, but because of being workable with local power system information, they have many difficulties on setting calculation and checkout, and are not satisfied with protection capabilities. How to improve on the means of calculation and checkout settings of protective relaying, and how to seek after new protective theory, criterion and performable scheme by new technology, are directions of working to all research people.One part of this paper is to research into developing integrated software of protection setting calculation, checkout and management, the software not only can improve the work efficiency of the protection department but also can secure the high validity of protection setting. The main achievement is as following:(l) Present a new software structure with insert mode based on diagram and data platform. With this structure the software can be used in various voltage levels of power networks by switching function groupware with corresponding edition. Therefore it is important to solve software' universality and developability. (2) Present a new idea that any operating condition is combination of running mode of plant or station, power supply topological and rules of equipment maintenance. This idea is very useful at simplifying setup and choice of operating conditions and ensuring calculation result correction. (3) Present a new idea of protection setting examination and rectification. Protection setting examination is used to examine the selectivity, sensitivity and speed under certain operating condition, and pass an opinion whether these settings are wrong;Setting rectification is used to calculate new relay settings when error is found in setting examination. (4) Point out that interaction design is the key step in developing power system application software,which can secure usability. The author also summarizes the course of software development and raises much useful experience. The results mentioned above are shown in the style of application software.The other research of this paper is how to improve present protection's capabilities or find a new performable scheme based on multi-agent technology. The achievement is as following:(l) summarize the application of agent technology in protection system and consider the future of application. (2) Present a concept on aggregate protection as result of agent transverse application and consider in details the functions, action criteria and preliminary implement scheme. Aggregate protection have following functions: accelerating the action of protection, shortening the power cut area, and avoiding the misoperation of relay under transmission line overload situation. (3) Present a tentative scheme of intelligent protection as result of agent lengthways application. The characteristic, functions and realization frame of intelligent protection is analyzed. These results are helpful to quest for future protection scheme using agent technology.