Abstract The paper proposes an energy consumption cross-level model for a demand driven machine tool working in a manufacturing system. The aim is to optimize performance of manufacturing system engaging more than one organizational level, in this case the machine and the system levels. The paper exploits a former study on Pareto optimal Minimum Energy-Time functions, representing the best possible machine setups under varying cycle-time. The functions are used to model machine productive states, whereas stochastic behaviours (failures, blocking, starvation) and inter-machine interactions are described using a Markovian General Threshold Model. Here, instead of using a constant power per machine state assumption, a functional relationship between processing rate and machine energy demand is used. A stand-by energy-saving policy, which exploits the flexibility in adopting a variable processing rate and a settable threshold level of the interoperational parts buffer as a trigger, is developed and benchmarked. The model is used to analyse an industrial case study of a three-station transfer machine. It takes into account a number of cost contributing factors, apart from sole energy demand, such as tooling cost, operator cost, inventory and costs related to potentially undelivered throughput. The application of the proposed cross-level optimization scheme to a case study showed an improvement both in energy-efficiency and in profitability of the production system under investigation. Moreover, it has been demonstrated that a model exploiting knowledge from both levels can avoid suboptimal setups resulting from treating single-level problems independently.

中文翻译：

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使用两机广义阈值表示的传送机能量需求的跨级模型

摘要 本文提出了一种在制造系统中工作的需求驱动型机床的能耗跨级模型。目的是优化涉及多个组织级别的制造系统的性能，在这种情况下是机器和系统级别。该论文利用了先前对帕累托最优最小能量时间函数的研究，代表了不同周期时间下可能的最佳机器设置。这些函数用于对机器生产状态进行建模，而随机行为（故障、阻塞、饥饿）和机器间交互则使用马尔可夫通用阈值模型进行描述。在这里，不是使用每个机器状态假设的恒定功率，而是使用处理速率和机器能量需求之间的函数关系。待机节能政策，它利用了采用可变处理速率和互操作部件缓冲区的可设置阈值级别作为触发器的灵活性，并进行了基准测试。该模型用于分析三工位移载机的工业案例研究。除了单一的能源需求外，它还考虑了许多成本影响因素，例如工具成本、运营商成本、库存以及与潜在未交付吞吐量相关的成本。所提出的跨级优化方案在案例研究中的应用表明，所调查的生产系统的能效和盈利能力都有所提高。此外，已经证明，利用来自两个级别的知识的模型可以避免因独立处理单级问题而导致的次优设置。