Acquisition Method And Applications Of Inherent Energy Efficiency Factors In Machine Tools

Discrete manufacturing industries are in enormous quantity and consume a great amount of energy with low efficiency.In recent years,improving energy efficiency in discrete manufacturing systems has become a key strategy and a hot topic for green manufacturing.As typical equipment in discrete manufacturing,machine tools have great potential for energy efficiency improvement and attract lots of researchers and managers.Developing energy-efficient machine tools and operating machine tools in high energy efficiency are two major ways for users to improve machine tools' energy efficiency.However,the existing energy efficiency research is mainly focused on how to improve the energy efficiency of machine tools in a single process,but far from enough on how to develop energy-efficient machine tools.In order to support the development of energy efficient machine tools,the inherent energy consumption characteristics of machine tools are required to be revealed firstly.To this end,with the support of the National Natural Science Foundation of China,this thesis proposes to use the Inherent Energy Efficiency(IEE)factors to reflect the inherent energy consumption characteristics of machine tools and the composition and acquisition of inherent energy efficiency factors as well as their applications are studied.The main work of this study is as follows:The composition and modelling of the IEE factors of machine tools are studied.Three kinds of inherent energy consumption characteristics,including time-consuming energy consumption characteristics and load loss characteristics of machine tools,are analyzed,and then the IEE components of four inherent energy consumption periods,such as machine standby period,processing preparation period,no-load period and cutting period,are revealed.The general model of the IEE elements of each period is also established,and the framework of the IEE factors of the machine tool is constructed as well.The acquisition method of the additional load-loss function which is the IEE key factor is studied.Firstly,the acquisition methodology of the additional load-loss function of machine tools based on the spindle power transfer feature is proposed.Then,the power consumption model of the inverter based on inverter's basic parameters and the power consumption model of the spindle motor based on motor's basic parameters are established to present the theoretical model of the additional load-loss function.Based on this,a method for obtaining the additional load-loss function of the machine tool is proposed by calculating the additional load-loss coefficient.Afterwards,the accuracy and practicality of the model are validated in experimental verification and application cases.The intelligent comprehensive acquisition method of the IEE factors is studied.In terms of the problems in exiting acquisition method,such as hard to measure,incomplete detection data and complicated data processing,the solution and process of intelligently acquiring IEE factors are first proposed.Then the key technologies such as the detection experiment design,the automatic generation of the NC program in the detection process and the adaptive modelling method of detection data are established.The support software system for the acquisition of IEE factors is also designed and developed to benefit the detection process.Finally,the feasibility and practicability of the above methods and systems are verified by application examples.The applications of IEE factors in the energy efficiency research of machine tool development stage and service stage is analyzed.The application framework of IEE factors in these two stages is established,and the content and direction of application research are also systematically analyzed.With the direction,the following two application research problems are planned.The first application research problem—the potential energy-efficiency assessment in the machine tool's development phase based on IEE factors is studied.Firstly,by establishing the machine-tool-related parameter model and the equivalent workpiece for the expected task,a potential energy-efficiency assessment model is established to reflect the energy efficiency performance of machine tools achieving the expected task of machine tool users.After that,the feasibility and practicality of the above energy efficiency assessment model is verified according to a case study of energy-efficient machine tool selection.The second application research problem——the acquisition and evaluation of energy efficiency in machine tools' service stage based on IEE factors are studied.The real-time energy efficiency acquisition method and the energy efficiency fine evaluation method based on IEE factors are established.An integrated application system based on the proposed real-time energy efficiency acquisition method and fine evaluation method is also analyzed.The study of the composition,modelling and acquisition methods of IEE factors can provide basic theoretical and technical support for the energy efficiency research of machine tools.At the same time,the application of IEE factors in the service phase and development stage of machine tools can provide technical support for the solution of energy efficiency improvement problems in a large number of machine tools.