制氢过程中一氧化碳氧化反应速率控制的平滑切换方法

铂族金属催化剂CO氧化过程呈现较为复杂的本质非线性属性,如反应速率突变、双稳定性和迟滞,这些本质非线性属性取决于化学反应内在的稳定性和自组织机制,所产生的一个外在结果是CO氧化反应速率与控制参数之间呈现出路径依赖的输入输出关系。对这类系统采用传统的线性控制方法具有固有的不稳定机制,可以导致化学反应速率的震荡以及控制系统的失稳;而采用常规非线性切换控制则面临在切换初始时刻所具有的大干扰问题,较大地影响控制系统的动态性能甚至稳定性。针对研究所面临的这种大干扰问题,提出基于积分初值重置的平滑切换控制方法予以解决。结果表明,所提出的方法能够从原理上解决CO氧化反应控制过程的平滑切换问题,较好地提高控制系统的动态性能。

Smooth switching scheme for the control of CO oxidation reaction rate in hydrogen production

The catalytic CO oxidation on platinum group metals exhibits complex intrinsic nonlinear properties, such as reaction rate catastrophe, bistability, and hysteresis. These intrinsic nonlinear properties depend on the inherent stability and self-organization mechanism of the chemical reaction. A corresponding phenomenon is a path-dependent input-output relationship between the CO oxidation reaction rate and the control parameters. The traditional linear control method for these systems has an inherently unstable mechanism that can give rise to the oscillation of the chemical reaction rate and the instability of the control system. However, the previous application of ordinary nonlinear switching control faces a large disturbance at the initial moment of switching, which will affect the dynamic performance and stability of the control system. For this reason, a smooth switching control method based on the integral initial value reset was proposed. The results show that the proposed method can provide a smooth switching control of CO oxidation reaction rate, and thus the dynamic performance of the control system is improved.