Boiler Combustion Advanced Control System Development Based On PLC And OPC

With the rapid development of China’s national economy, the demand for power increase rapidly. Coal-fired power production of thermal power in the dominant, every year consumes large amounts of coal resources, and the resulting air pollution is very great, and, the coal boiler furnace combustion condition is very complex, involving burning, flow, heat transfer process and other aspects, such as by air, wind speed, the ratio of wind, coal types, pulverized coal concentration and fineness and unit load and the influence of various factors. Also, these factors often influence each other, interwoven with each other, increased the complexity of the combustion process, so testing and improving the coal-fired power plants burning operating mode, to solve the power station boiler operation of facing double requirements-reduce the operating cost and reduce emissions, also have important significance.The boiler combustion control system is a typical of multivariable, nonlinear, time-varying, large delay, complex system, object model is hard to develop, using the traditional control method is difficult to achieve the ideal control effect, so it is necessary to research a new intelligent control strategy to satisfy control requirements. And because the fireman feed machine speed control to powder amount with experience, but in fact, the speed and powder amount is not linear, many domestic power station in the actual operation of process, with the four uneven wind and wind with coal disorders, cause the boiler tube blasting and burner damage deformation, and fire accidents occur frequently. The main content of this article as follows:1. This paper based on the fuzzy control theory and conventional control organically, and developed a set of advanced boiler combustion control system:(1) the main steam pressure control system, take the main steam pressure as the main controller parameters, pulverized coal as vice control parameters with the fuzzy PID control strategy of new balanced combustion control system.(2) the sending wind control system, adopting the oxygen levels in flue gas as the controller parameter PI cascade control system.(3) the drawing wind control system, uses sending wind content act as feedforward variable and using drawing wind content act as control variable.2. Combining the fuzzy control technology, based on OPC technology, the fuzzy control software package has been designed. The general framework of the package has been presented, Its function modules have been designed in detail.3. Using of Visual Basic6.0tools to implement OPC client, read the real-time data from the force control OPC server and processing data.4. This paper using IPC and configuration software and PLC constituted a small distributed control system, according to the control thought designed the overall structure of the combustion system,. I chosen PLC as burning system of a machine, and explained the hardware choice and configuration. Then I made a detailed instruction on software design and implement. Using force control6.0, PC communicate with the under machine and provide operation process real-time. According to actual situation, calculate combustion system target, For the parameters deviated from the target put forward alarming, finally, increase the combustion efficiency of the system. The research development result indicated:this system fuses the configuration software and the advanced algorithm, enhanced automation level and management level of boiler combustion system. The system will bring the obvious economic efficiency and the social efficiency.