Distributed Control Of Wastewater Treatment System And Performance Analysis

Along with industrialization degree advancing and city population density increasing in our country, wastewater treatment technics becomes more and more complex. And wastewater treatment control systems needed become more and more advanced. In this thesis, a high-powered Distributed Control System (DCS) for wastewater treatment is designed in order to optimize system control. This system consists of main computers, slave computers, sensors and transmitters etc. In order to optimize the control of the wastewater treatment process, some parameters were selected for global parameters by analyzing , weighing and comparing the given parameters. For limited bandwidth, the time delays exist in transmitting data and feedback control signals in globally control. Under time-delays, the control effect will be affected, the system performance will degenerate and even the system will be out of control. In order to not only optimize control but also get good system performance, the time delays effect on system performance is studied based on constructing the wastewater treatment DCS. Based on defined a new performance criterion, the DCS performance degenerating function is constructed, and the model of DCS multiple time-delays performance analysis is set up. This model is used to study the system stability and performance degenerating. And the system stability is validated under time-delays by system simulation.This study provided some useful ideas for designing wastewater treatment control system in our country. And the new research is made in the field of DCS performance. The model could provide the evidences for another DCS designing, servicing and improving.