The analysis of equipment degradation has traditionally developed in two main directions. One approach, of great interest for control system design, has been to consider that degradation causes fundamental changes to the behaviour of a system. Another approach, used in optimal maintenance planning and production scheduling, considers degradation as a separate process that affects performance but does not necessarily change the behaviour. This article provides a review of mathematical models of degradation that will facilitate the integration of degradation modelling into control and optimisation schemes. To this end, a new unified classification is proposed. It takes into account the influence of degradation on the behaviour of the system, as well as the factors influencing degradation. Understanding these mutual influences will enable improved optimization, design and operation of control systems. The flexibility of the proposed classification is demonstrated in an industrial application to a multi-product batch scheduling process.

传统上，对设备降级的分析已朝两个主要方向发展。对于控制系统设计非常感兴趣的一种方法是考虑性能下降会导致系统行为的根本变化。在最佳维护计划和生产计划中使用的另一种方法将降级视为影响性能但不一定改变性能的单独过程。本文提供了退化的数学模型的综述，这将有助于将退化模型集成到控制和优化方案中。为此，提出了一种新的统一分类。它考虑了降级对系统行为的影响以及影响降级的因素。了解这些相互影响将有助于改进控制系统的优化，设计和操作。拟议分类的灵活性在工业应用中证明了对多产品批次计划的过程。