【作者】 施金良；

【导师】 刘飞；

【作者基本信息】 重庆大学 ， 机械制造及其自动化， 2009， 博士

【摘要】 我国机床装备拥有量居世界第一,耗电总量惊人。同时,大量统计调查表明:机床能量利用率非常低下。因此对机床运行过程能量特性及节能技术的研究意义重大。本文针对已有研究在数控机床能量特性方面的不足,在国家自然科学基金课题(编号:50775228)和国家科技支撑计划项目(编号:2006BAF02A03)的支持下,对我国目前广泛应用的变频器调速数控机床的能量特性及节能技术展开了研究。其主要内容包括:根据变频调速数控机床运行过程的能量传输特点,建立了变频调速类数控机床主传动系统的能量流程,分析了机床主电机功率传输特性和机械传动系统功率传输特性及其各部分的能量损耗规律;在上述研究基础上,建立了变频调速数控机床主传动系统的动态功率平衡方程。该方程相对于普通机床功率平衡方程,具有变频器自身存在较大的能量损耗、变频器输出的非正弦波形电压带来的电气谐波损耗和机械传动系统的机械脉动损耗、主传动系统当量角速度具有一致连续性等三个重要特点。并在上述功率平衡方程的基础上分析了变频调速数控机床运行过程的能量利用率和能量损失特性。基于上述功率方程和能量损失特性,对变频调速数控机床运行过程的节能途径进行了分析,指出了从四个途径来系统地考虑机床运行过程的节能问题。机床加工过程工步间空载运行过程是一个能量损耗过程,是造成机床能量利用率低的直接原因之一。本文根据变频调速数控机床工步间空载运行过程转速和时间已知并且转速可无级变频调节等三个特点和条件,提出了一种机床空载运行时动态调节机床空载运行转速、使得空载运行过程能量消耗达到最低的变频调速数控机床工步间空载运行状态的调速节能方法。当数控机床加工过程工步间空载运行时间大于某一临界值时,采取工步间停机后再启动策略就可以取得比调速节能更好的节能效果;为此本文建立了基于临界值确定方法和节能百分比计算方法的数控机床工步间空载运行时停机节能的实用方法。根据电机的转差率的变化,通过调节变频器装置的输出电压来控制电机运行转差率,并基于神经网络模型参考自适应的控制算法实现了交流异步电动机在不同负荷下最优转差率的控制,从而达到电机在不同负载下的节能运行。针对以上研究内容,在一台变频调速数控机床CK6136上进行了大量实验,实验数据及实验结果分布在各有关章节中;实验结果证实了有关结论的正确性和应用前景。更多还原

【Abstract】 The amount of machine tools in China is largest in the world, and the total energy consumption is remarkable. Therefore, the study on energy characteristics and energy saving technology in the running processes of machine tools is very important.Considering the insufficiency of existing studies on energy characteristics about CNC machine tools, this paper focuses on the studies on the energy characteristics and energy saving technology about CNC machine tools driven by VVVF(Variable Voltage Variable Frequency) with the supporting of the National Natural Science Foundation of China and National Science and Technology Supporting Programs. The details are as follows.According to the characteristics of energy transmission in the running processes of CNC machine tools driven by VVVF, the energy flow-chart of main driving system is established. The power transmission characteristics in the main motor and the mechanical transmission system, and every section’s energy losses are analyzed. Finally, the power balance equation of the CNC machine tool main driver system driven by VVVF is established. Comparing with the equation of common machine tools, this equation has three characteristics: It includes the variable frequency driver’s energy loss;The variable frequency driver’s no-sine voltage wave causes mechanical pulse losses in mechanical driving system;Equivalent palstance of main driving system is of uniform continuity。Based on the equation, the energy utilization and energy loss characteristics are analyzed.Four methods of saving energy about the CNC machine tools driven by VVVF are analyzed .It is based on the power balance equation and the power transition characteristics. The process of CNC machine tools idle running is a energy consumption process,and this is the one of main reason of lower energy usage of CNC machine tools. According to the three conditions which are specified speed, specified time and the speed characteristics of continuous variable , A saving energy method which via controlling the speed of main driver of CNC machine tools in the process of idle running is given.When the interval between two process steps is larger than an specified value,The method of energy-saving that stopping CNC machine tool’s between process steps is much better than the method of controlling the speed of main driver of CNC machine tools.So an practical method of energy-saving is introduced in the paper. The method is realized by stopping CNC machine tool’s when the running process is idle between process steps. The critical value and the computing of saving energy percent also is given in the paper.Because of the slip speed will change when the voltage of VVVF is changed, so we can control the slip speed by controlling the outport voltage of VVVF, A saving energy method of main driven motor of CNC machine tool which running in the defferent state of load is introduced in the paper .This method is realized by optimizing the slip speed in the defferent load state based on the adaptive neural network.The research results are proved and having a good application perspective by some experiments.The experiments is done on the CNC machine tool (CK6136) which main driver is driven by VVVF. The result of experiment is given in the defferent chapter in the paper.更多还原