基于自抗扰方法的单元机组协调系统设计

Active disturbance rejection control in thermal power unit coordinated control system

针对燃煤大型火电机组运行过程中普遍存在的煤质变化及外界不确定性扰动频繁,控制对象复杂等特性造成的常规协调控制策略无法满足电网自动化负荷控制要求的问题,提出了一种具有前馈补偿和近似静态单向解耦控制结构的机炉协调自抗扰控制策略。该控制策略在自抗扰控制器对扰动的跟踪补偿作用下可以使机组协调控制系统在汽机-锅炉控制回路强耦合和外部干扰的影响下实现对电网负荷指令的快速稳定跟踪,并且对机组运行工况和模型不确定性有很强的鲁棒性。仿真结果表明,在协调控制系统功率扰动和给煤机转速扰动及模型参数摄动影响下,单元机组依然具有良好的动态特性。

A Considering the situation that normal coordinated control strategy can not meet the requirements of network automation load control when large coal-fired thermal power plants run with unmeasured pulverized coal disturbance, frequently uncertainty external disturbances and complex control object, a boiler-turbine coordinated control strategy combing feedforward compensation and approximate static one-way decoupling control structure with Active Disturbance Rejection Control （ADRC） was proposed. Thermal power unit with strong coupling and external disturbance in Turbine-Boiler control loops could fast and stably trace power grid load command by ADRC tracking and compensating the disturbance. Meanwhile, this strategy has strong robustness on operating conditions changing of the unit and the model uncertainty. The simulation results showed that the designed control method not only adapt to power and coal feeder rotate speed of coordinated control system disturbance and model parameters perturbation but also has good dynamic characteristics.