Microcomputer Monitoring And Protection

This thesis mainly discusses the research on the development of Microcomputer measuring and protection device of power system based on DSP technology. The work includes the analyze of protection theory, hardware system design of the device and the development of the software system.In the design of the device.Firstly,it analyses the protection theory of devices in Mid&Low-voltage power system. Then we promote the stable and reliable judge basis of all kinds of the equipments(motor,transformen, capacitor).Based on the analysis, We design the hardware system of the device, and put emphasis on the thorough research and design of the hardware system of the modularized and united microcomputer measuring & protection device used in Mid&Low-voltage power system, including CPU unit, MMI unit, A/D conversion unit, exit unit, communication unit and the measurement of frequency and phase unit. We discuss the software modules of the device, including the main routine and the interrupt service routine. Based on the analysis of the requirement and characteristic of sampling AC electrical parameters, the advantages and disadvantages of many common algorithms and their application fields, we promote a kind of algorithm considering both high calculating speed and precision realized on the DSP platform. The thesis also puts emphasis on the design of all software unit of the device, including the main routine and the interrupt service routine.Besides, It aims at the problems encountered during the debug process such as "un-matching of interface timings between the DSP chip and LCD or communication modules", "distribution of memory space", "Sampling and algorithm optimism problems" and so on, thus promoting the improved schemes on these questions.