Research On Automotive Powertrain Prodution Planning And Scheduling Optimization Problem

The powertrain plant is a very important part of the passenger car manufacturing system.It mainly produces core components such as the engines,gearboxes and batteries of the car.According to our survey,at present,the powertrain plant of automobile manufacturing enterprises in China still adopt the method of manual planning,which is relatively inefficient and may lead to the high cost in production.In order to quickly respond to the ever-changing market demand,the automation of the powertrain plant planning is very important.The production planning of the powertrain plant has a specific requirement that the inventory of all parts at any time cannot be lower than the safety stock.To satisfy this requirement,this dissertation establishes a mathematical model that minimizes the inventory holding cost and changeover cost,taking into account safety stock constraints and capacity constraints.Then,a set of safety stock constraints based on the concept of minimum production amount is proposed,which makes the model have a tighter linear relaxation lower bound.According to the characteristics of the mathematical model,a heuristic algorithm to generate initial solution is designed and a relaxation model is constructed.The relaxation model is solved by the Dantzig-Wolfe decomposition and column generation algorithm,and then the local search is performed to obtain the solution of the original problem.This dissertation uses the real-world data to verify the model and compare the algorithm.Experiments show that the proposed algorithm is very effective in solving large-scale problems.Finally,this dissertation proposes a production planning system framework for practical production,and compares the production plan with the manual production plan.The result shows that the method of this dissertation can reduce the inventory holding cost and the changeover cost,and greatly shorten the planning time.