Modeling Simulation And Optimal Control Of Combustion Control System On Large-scale Thermal Power Unit

With the rapid development of society, the environment issues and the energy issues has become China and even the worldwide common focus. In term of our country, the coal-fired power plant are mainly in the electric power industry of our country today and in a long period, it was decided by the social condition of our country and the unique energy pattern. With the structural adjustment of power industry, power project crew to concentrate on building a large unit, Thermal power generating units in China also has high-parameter, high-efficiency, the development of large-capacity supercritical units. Supercritical units as an international on both a reliable, mature and in the development of thermal power generating units, be included in the development of clean coal technology in the international track and significantly reduce its coal consumption rate than conventional subcritical units, energy saving and environmental protection significance. This paper analyzes the working principle of combustion systems of Supercritical Unit, the production process and the control tasks, and describes the overview of all equipment and operational specifications of power plant 600 MW supercritical Units in Xi'an.The supercritical unit combustion system transforms the heat generated by burning coal to mechanical energy. It provides energy source for the whole thermal power plant. So it is necessary to study combustion control system of large scale thermal unit deeply in order to improve operational efficiency of thermal unit. In this paper, the supercritical unit combustion control system is studied, the correlative study mainly focused on the two aspects, object modeling and control arithmetic.An accurate system model can reflect exact parameters of thermal equipments and the dynamic response process. It can improve the control strategy of the supercritical unit combustion control system, also it can help us understand dynamic characteristics of the thermal system. We can use intelligent algorithms to identify the model of the supercritical unit combustion control system based on field data for a run condition, and we can get the mathematical model which is relatively close to the requirements of the field. This paper presents the characteristics analysis of the main steam pressure system, the flue gas oxygen system and three subsystems of combustion system of the 600 MW supercritical unit, and this paper uses particle swarm optimization based on field operational data to identify the model of the three subsystems. By comparing the identification results with the original data, we can verify the feasibility of the system model based on field performance data.Due to the supercritical unit combustion control system with strong coupling,large inertia and variable characteristics, conventional control method can't meet the higher control performance requirements. This paper designs particle swarm optimization for the supercritical unit combustion control system in order to achieve stable and rapid control effect, particle swarm optimization can adjust controller parameters intelligently according to the combustion control system's state. It has faster response, better tracking ability, more strong anti-interference ability and better robustness. In this paper, the optimization results of particle swarm optimization and the optimization results obtained from the PID empirical tuning formula are compared and analyzed, and the corresponding optimization effect contrast curve is given, it is fully validated that particle swarm optimization controller for complex dynamic characteristics of combustion control system has a better control characteristic.