Design And Energy-Saving Optimization Of Air-Conditioning Control System For Automobile Painting Workshop

With the development of industry and the improvement of living standards.People pay more and more attention to car appearance.Car buyers like clean,beautiful,and flawless painting.In the whole vehicle manufacturing,the painting workshop is responsible for body painting.The air-conditioning system provides the painting environment to meet the process requirements,including cleanliness,wind speed,temperature and humidity,etc.,which directly affects the quality of body painting and the safety and comfort of production personnel.Moreover,the production process of painting workshop and air-conditioning system deplete much energy.In the energy consumption of the whole factory,the painting workshop is 60%.Air conditioning system is 50% of the workshop.Therefore,the stability,reliability and energy saving of air conditioning control system are required.This paper combines the author’s 5-year field work experience in painting workshop.Based on the air-conditioning system design project of a domestic automobile factory painting workshop.A set of air-conditioning control system is designed from the practical application of engineering.Whole system realizes the design requirements of equipment automatic control,temperature and humidity automatic regulation,stability and reliability,site visualization and convenient management,and fully considers energy saving optimization in the design and production operation links,and integrates the concept of green environmental protection,bringing energy-saving economic benefits for enterprises.This paper firstly aims at the external weather environment of the painting shop and the air supply temperature and humidity requirements of different workstations and production areas.The combined air-conditioning system is designed.According to the air treatment principle of each functional section in the air-conditioning system,combined with the study and research of air state parameters and psychrometric chart,the type classification of system and the combined design of the functional segments have been completed.On the basis of air conditioning system structure and automatic control demand,the hardware of equipment layer and Siemens S7-1500 series PLC of control layer are selected.Then,TIA protal software is selected for software system configuration and program design.The air-conditioning season judgment program is compiled by using the Psychrometric Chart principle,and the control program of energy equipment such as cold and hot water pump,humidification pump,burner and other energy equipment in temperature and humidity regulation is compiled by using PID control principle,and the HMI upper computer screen is drawn and designed.By downloading the PLC program and HMI screen to the on-site hardware equipment,after a series of parameter settings,system debugging and trial operation.The results show that system can realize the automatic start and stop,and automatic adjustment of temperature and humidity.The operating status and parameters of the equipment can be viewed in real time on the HMI.It can realize online operation and parameter modification.These meet the design requirements of the air-conditioning system in the painting workshop and ensure a good painting environment.This paper also introduces two energy-saving optimization measures and their economic performance during the run-time.Wish to provide some reference for the same type of air-conditioning energy saving in painting industry.