Research On Coordinated Control System Ot Ultra-Supercritical Unit Based On Multivariable Predictive Control

The energy structure of our country determines that the power industry in our country is still mainly coal-fired power generation.Ultra-supercritical unit technology has good inheritance and is easy to be implemented in large-scale.Improving Ultra-supercritical unit proportion and optimization of Ultra-supercritical unit control level is an important direction of promoting the coal-fired power generation technology.Coordination control system of Ultra-supercritical unit is developed on the basis of the traditional boiler-turbine control system.It is the core of thermal power unit control system.Improving the level of Ultra-supercritical unit coordination control is very important to improve the efficiency of Ultra-supercritical unit.Ultra-supercritical units have complex and volatile controlled characteristics and the boiler of the Ultra-supercritical unit is once-through boiler.It needs to operate with high parameter and adapt to a wide range of load change,the coordination control of Ultra-supercritical unit has the control difficulty.Based on this,this paper puts forward the research of coordinated control system based on multivariable predictive control and intelligent feedforward.Among them,multivariable predictive control is based on predictive control in the form of extended state space.The effective control method solves the quadratic programming objective function to get the optimal control quantity.Intelligent feedforward is designed to feed coal intelligent feedforward mainly in response to slow response of boiler side,including two parts,static and dynamic.The static part is based on the precise balance of energy designed feedforward baseline feedforward to determine the target load under the command of the total amount of fuel under the reference,while the dynamic part includes the pre-feed coal,the pressure back and differential pressure differential Feedforward.Through these feedforward,fully taking into account the dynamic compensation of the unit energy storage,the boiler give a certain amount of overshoot combustion to speed up its response to ensure the rapidity of the unit.Finally,based on the development of intelligent DPU,the simulation configuration is set up in the virtual DPU,and real-time simulation with or without feedforward,carried out.At the same time,compared with the fuzzy gain scheduling algorithm,the validity of the system control effect is further verified.