Abstract: Mechanical manufacturing system is a strongly coupled system of production and energy. In view of its coupling characteristics, a dynamic modeling method of carbon flow based on extended first-order hybrid Petri nets is proposed. The dynamic characteristics of carbon flow are analyzed for mechanical manufacturing system, and its corresponding system boundary is established. Production structure and operating model of maufacturing system, balance equations of energy and material and the formula for calculating the carbon emissions are derived from the system boundary, laying a quantitative analysis foundation for the following model. With respect to the continuity of energy and the impact of discrete state on the continuous processes, based on the original first-order hybrid Petri nets, controllable arcs and inhibitor arcs are introduced in order to enhance the modeling semantics, and the formal definition and rules explanation of the model are given. The model is applied to a manufacturing system automatic production line. The multi-objective function is established with the constraints, the time domain characteristics of the energy flow, material flow are simulated and optimized, and the corresponding carbon emissions are calculated. The method lays a theoretical foundation for the enterprises to carry out low-carbon manufacturing.

Key words: Carbon flow, Coupling characteristics, Hybrid Petri nets, Low-carbon manufacturing