基于GSO的锅炉主蒸汽压力串级PID优化控制

Cascade PID Control of Main Steam Pressure Based on Glowworm Swarm Optimization

火电单元机组主蒸汽压力对象具有大迟延和大惯性的特点,而且受到机组负荷及燃烧状况等因素的扰动频繁,常规的反馈控制很难兼顾系统的快速性、准确性和抗干扰能力。由于炉膛辐射能信号能够直接实时地反映燃料量或者燃烧品质的改变,引入炉膛辐射能信号作为中间被调量,从而形成一种基于炉膛辐射能的主蒸汽压力串级控制系统,并利用萤火虫算法获得ITAE性能指标下最优的串级PID控制器参数。仿真结果表明,上述控制系统能够有效克服各种干扰对主蒸汽压力的影响,维持主蒸汽压力的稳定,提高系统的控制品质。

It is difficult for the conventional feedback control to guarantee both rapidness and precision because of the characteristics of long time-delay and large inertia of the main steam pressure process. The radiant energy can reflect the change of the fuel and the quality of combustion more directly and timely. A main steam pressure control system based on radiant energy is established,which takes radiant energy signal detected from furnace as an intermediate control variable. Through the glowworm swarm optimization,cascade PID controller with optimal ITAE criterion is obtained. The simulation results show that the new control method can efficiently overcome the fuel and load disturbance to maintain the main steam pressure stability,and can obviously enhance the control quality.