Research Of Microcomputer Protection Experimental And Teaching Platform Based On Atmega128

Microcomputer protection has been used widely in power system. Almost all the new substations and power plants use microcomputer protection system now. During the teaching progress of" Protection in Power System" course in colleges, most of the laboratories use electromagnetic relay-to explain the basic theory of relay system. This brings about the disconnection between teaching and practical application. In this paper, We provide a new plan to compose a microcomputer protection training system based on the characters of other test system used in foreign university now. The plan to compose this microcomputer protection testing system is proposed. According to this plan, We designed some external device to sample analog signal and digital signal. At the same time, Some training projects are provided based on the experimental devices.This paper contains following aspects:1, Analysing the problems in the teaching progress of "Protection in Power System" course, The microcomputer protection training system is currently used in colleges and relative information are studied, The main contents are researched in this paper are put forward.2, Merits and demerits of hardware are compared in this paper. According to the characters of this training system, Direct connection pattern is selected as the basic structure of this training system. Relative hardware and circuit are selected to make the training system work properly. The hardware and circuit designed in this training system contain displaying circuit, keyboard circuits, analog input circuit, switch input and output circuit, etc.3, In order to make the microcomputer protection experimental device work under the practical condition, The external circuit to analog practical work condition was designed in this paper. This external circuits provide short-circuit current, voltage and relative switch signal. Then some experimental projects are designed to meet the training denmands. The experimental projects contain setting value modifications,control word set experiment; Maximum, minimum operation mode to determine the scope of protection experiment, Fault happened in the inner field simulation experiment; Experiment about three segments protection coordinative actions in one site; Experiment about three segments protection coordinative actions during different sites.4, Based on the hardware and circuit designed properly in this plan, and the corresponding experiment projects provided in this paper, We designed a software system to make the training system work properly under the practical condition.5, Finally, This microcomputer protection testing system can work properly under parctical condition after debugging.