Method and system for formulating an energy-saving strategy for semi-automatic production line based on model predictive control

Patent metadata

Field	Value
Publication number	US-2024255902-A1
Application number	US-202418430606-A
Country	US
Kind code	A1
Filing date	Feb 1, 2024
Priority date	Feb 16, 2023
Publication date	Aug 1, 2024
Grant date	—

Abstract

An energy-saving strategy formulation method for a semi-automatic production line based on model predictive control is performed as follows. max-plus algebra model is constructed, based on which an optimization objective function with the WIP products as discrete elements and sleep start moment and sleep end moment of the automated device as control variables is established. A first unoptimized WIP product is substituted into the optimization objective function, and the optimization objective function is solved to obtain an optimal sequence, in which a first set of values is output as optimization result. Whether all WIP products have been optimized is determined, and if yes, an energy-saving strategy is generated and used to control the automated device, otherwise, the optimization result is treated as disturbance information to be incorporated into the modeling. An energy-saving strategy formulation system is also provided.

First claim

What is claimed is:

1 . An energy-saving strategy formulation method for a semi-automatic production line based on model predictive control, comprising:
(S 1 ) constructing a max-plus algebra model of the semi-automatic production line, wherein the semi-automatic production line comprises work-in-process (WIP) products and an automated device; and the max-plus algebra model is a production line model without controlling start and the stop of the automated device; (S 2 ) establishing, based on the max-plus algebra model, an optimization objective function with the WIP products as discrete elements, and a sleep start moment and a sleep end moment of the automated device as control variables; (S 3 ) substituting a first unoptimized WIP product among the WIP products into the optimization objective function, and solving the optimization objective function to obtain an optimal sequence comprising the sleep start moment and the sleep end moment of the automated device; and outputting a first set of values in the optimal sequence as an optimization result for the first unoptimized WIP product with respect to the automated device; (S 4 ) determining whether all of the WIP products in the semi-automatic production line have been optimized, if yes, proceeding to step (S 5 ); otherwise, treating the optimization result as a disturbance information, and returning to step (S 1 ) to incorporate the disturbance information into the construction of the max-plus algebra model; (S 5 ) generating an energy-saving strategy based on optimization results corresponding to all of the WIP products; and (S 6 ) controlling the automated device based on the energy-saving strategy.

2 . The energy-saving strategy formulation method of claim 1 , wherein in step (S 2 ), the optimization objective function satisfies the following formulas (1) to (4):

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Assignees

• Univ Guangdong Technology

Inventors

• Zhang Ding
• Yang Jiafeng
• Liu Qiang
• Yan Duxi
• Zhao Rongli

Classifications

• G05B13/048

  using a predictor · CPC title

• G05B13/047 Primary

  the criterion being a time optimal performance criterion · CPC title

• Y02P80/10

  Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier · CPC title

• G05B13/042 Primary

  in which a parameter or coefficient is automatically adjusted to optimise the performance · CPC title