Extremum-seeking control for power consumption minimization in gas liquifiers

Praxair的工业气体业务是非常能源密集型的。任何实现Praxair运营用电量减少的技术都将产生巨大的财务影响。液化大量气态氮的主要过程是通过一系列压缩机和涡轮机与多芯换热器相耦合。这些操作的组合被称为液化器。液化过程是一个非常耗能的过程；因此，即使总用电量略有减少(1%)，对Praxair和电力公司也非常有吸引力。虽然Praxair一直在寻找降低能耗的方法，但目前还没有系统和有效的方法来优化液化设备的运行；因此，Praxair认为Martin Guay博士在极值控制领域进行的研究对提高Praxair液化设备运行的效率具有很高的相关性。在液化操作中，有多个变量可以进行优化；然而，对电耗影响最大的是与相对较少的优化变量有关的变量。因此，在给定的工厂生产率和温度条件下，确定这些变量的最佳值，将使电力消耗最小化，并将导致最佳运行。

Praxair's industrial gas business is very energy intensive. Any technology that achieves a reduction of Praxair's operational electricity consumption would have a large financial impact. The main process to liquefy large amounts of gaseous Nitrogen is through a series of compressors and turbines coupled with a multiple core Heat Exchanger. The combination of such operations is called a Liquefier. The liquefier process is a very highly energy intensive one; as such, even a small reduction (1%) in the total electricity usage will be very attractive to Praxair and electricity companies. While Praxair is always looking for ways to reduce energy consumption, currently there is no systematic and efficient way to optimize the liquefier operations; as such, it is the belief of Praxair that the research conducted by Dr. Martin Guay, in the area of extremum seeking control, is of high relevance to increasing the efficiency of Praxair Liquefier operations. In liquefier operations, there are multiple variables that can be optimized; however, the largest impact in electricity consumption is associated with a relatively small number of optimization variables. Therefore the determination of the optimal values of such variables, at a given plant production rate and temperature conditions, will minimize the electricity consumption and will lead to optimal operation.