Method And Application For Data Compression And Data Decompression Based On DCS System

The developments of computer technology and the complexity of the industrial control system have explosively increased the quantity of process data measured in the production process.Abundant data need to be stored because they bring a lot of useful information that will benefit many sorts of the running and controlling tasks. However,these data inevitably carry much redundant and irrelevant information resulted from the measuring and the computing errors and even out of some human factors.Moreover,with the development of the network technique,the remote and network- based monitoring and controlling strategies become popular in the industry production process.And they both require large amount of the process data transmitted in real time via the network in order to share the data resources.Thus it is necessary to develop the real- time process data compression technique to reserve the major characteristic information of the process,to save the data storing space,as well as to reduce the data stream and to improve the speed and the efficiency of the data transmission.Accordingly,it is necessary to develop the data compression technique which would serve the mill- wide automation system and improve the performance concerning precision and real time in automatic technology.There are three main methods for process data compression up to now,such as piecewise linear compression,vector quantizer compression and transform compression.Among them,wavelet transformation is regarded as the most promising process data compression method for its many good characters,especially those in data processing area.The main contributions include the following aspects:(1)Design the data saving structure according to the characteristics of the detailtree data compression method and the characteristics of the data.(2)Analysis the existing problems of the detailtree data compression method and suggest an effective way for choosing the compression period of the detailtree data compression method,besides provide an reliable way to solve the problem of data shortage.(3)After the experiments,it can be concluded that detailtree data compression method woks well.(4)Design the data decompression method based on the characteristics of Harr wavelets,we called it detailtree data decompression method.After the experiments,it can be concluded that detailtree data decompression method woks well.(5)Complete hardware setup,function design,HMI design for DCS system of cement production.(6)Analysis the effects of detailtree data compression and decompression method according to the cement production DCS system.And datas with different characteristics were chosen to check whether the compression and de compression method work effectively.And finally,a reasonable result is presented.