Model And Optimal Control On The Load Control System Of Ultra-supercritical Units

Ultra-supercritical power plant has become the important developing direction of China thermal power industry, due to its low coal consumption rate, high generating efficiency, good reliability, and environmentally friendly properties. With the development of smart grid, the improvement and optimization of load control system are necessary to be researched for meeting the change of power consumption structure and network load. In this paper, aiming to build a load control system model in the simulation system, the thermodynamic characteristics of load control system in the ultra-supercritical power plant was analyzed. And a model for control is established based on the preceding analysis. The dynamic behavior of thermodynamic objects has characterizes of great inertia, long time delay, time-varying, strong coupling and uncertainty. This paper mainly makes the qualitative and quantitative analysis for ultra-supercritical generating unit load control system. According to the load control system, multivariable, strong coupling, nonlinear and other distinctive features, we put forward to taking the load control system control object for modeling. Then we take the modeling of combustion system for example and use the PSO for algorithm parameter identification after analyzing a variety of algorithm. Basing on the analysis of load control system structure, system composition and heat transfer calculation principle, we take the steam system, boiler system in steam turbine, pulverizing system module for example,list out relevant design methods and algorithms and build1000MW the ultra-supercritical generating unit load control system in Xuzhou by the LN2000simulation supporting platform and the EDPF DCS system. After the examination by historical data, we find that the model has high reliability and good control effect. After all we simplify the control model to three out of three into system. By introducing and analyzing the methods of load optimization by fuel optimization,It concludes that the optimization control method and sliding pressure constant dynamic optimization method have a better effect for improving the load control system.