基于PLC控制的空气悬挂空压机等熵效率测量系统  

PLC-controlled based isentropic efficiency measurement system for air-suspended compressors

作　　者：周庆霞 卿兆波 李坤鹏 ZHOU Qingxia;QING Zhaobo;LI Kunpeng(College of Mechanical and Electrical Enginnering,China Jiliang University,Hangzhou 310000,China)

机构地区：[1]中国计量大学机电工程学院,浙江杭州310000

出　　处：《现代电子技术》2025年第6期16-22,共7页Modern Electronics Technique

摘　　要：对空气悬挂空压机的等熵效率测量系统进行了深入探讨,提出一种最优测量等熵效率的系统。首先详细分析了计算等熵效率的步骤,并探讨了输入参数对等熵效率不确定性的影响。通过充罐排气量检测方法构建了试验装置,并设计了基于S7-200-SMART PLC控制的等熵效率检测系统。该系统采用VB6.0作为上位机软件,并通过ModBus协议及RS 485接口实现与PLC或触摸屏的点对点通信。研究还分析了等熵效率不确定性的来源,通过量化不确定度及其偏导数来估算各输入量对等熵效率的影响程度,进而预测空压机的性能变化趋势。测试结果显示,压力比是影响等熵效率的主要输入量。进一步试验表明,随着压力比的增加,等熵效率的不确定性区域稳定,最终达到3.6%,则在此条件下评估空压机性能的等熵效率是可靠的。An in-depth discussion on the isentropic efficiency measurement system for air-suspended air compressors is conducted,and a system design for optimal measurement of isentropic efficiency is proposed.The steps of calculating isentropic efficiency are analyzed in detail,and the influence of input parameters on the uncertainty of isentropic efficiency is explored.The testing device is constructed by means of the method of filling tank exhaust detection,and the isentropic efficiency detection system based on S7-200-SMART PLC control is designed.In the system,VB6.0 is used as the upper computer software to realize point-to-point communication with PLC or touch screen by means of ModBus protocol and RS485 interface.The sources of uncertainty in isentropic efficiency are analyzed,and the impact of various input quantities on isentropic efficiency is estimated by quantifying uncertainty and its partial derivatives,so that the performance trend of the air compressor is predicted.The testing results show that the pressure ratio is the main input quantity that affects the isentropic efficiency.Further experiments show that as the pressure ratio increases,the uncertainty region of isentropic efficiency stabilizes,ultimately reaching 3.6%.Therefore,the isentropic efficiency for evaluating the performance of air compressors under these conditions is reliable.

关 键 词：空气悬挂 空压机 PLC控制 等熵效率 充罐法 排气压力 不确定度评估 

分 类 号：TN925-34[电子电信—通信与信息系统] TP274.2[电子电信—信息与通信工程]