【作者】 刘健；

【导师】 谢慕君；

【作者基本信息】 长春工业大学 ， 控制理论与控制工程， 2012， 硕士

【摘要】 随着化工、煤矿、石油以及冶金等产业的迅速发展,离心式空压机作为这些领域大型企业的重要装置,其耗能也占据相当大的比例,因此对其节能控制的研究显得尤为重要。在空压机实际运行过程中,对空气的压力和气体的流量的要求是变化的,因此会出现运行工况点偏离的情况,所以要改变空压机的运行工况点。在对其本身的特性曲线以及与管网联合运行的特性曲线分析的基础上,以离心式空压机节能为目的,对变工况的调节方式展开了研究和对比。目前主要有节流调节、变空压机元件调节以及变空压机转速调节三种方式。其中,变转速调节相比前两者是最为经济的。改变压缩机转速是通过调节其驱动电机实现,本文针对功率比较大的电励磁同步电动机(简称：ESM)调速方法进行研究。电机的调速采用的是变频调速。变频调速方法中主要有矢量和直接转矩两种控制方法。矢量控制相比较直接转矩控制具有稳定性好、控制精确度高、变频器输出容量大等优点,并且针对空压机的负载特性以及对转矩要求不高等特点,本文采用了这种控制方法控制电励磁同步电动机。本文采用的矢量控制是基于气隙磁链定向的,使电励磁同步电动机的控制性能类似直流电机,控制难度被简化并且获得很好的控制效果。控制系统中的磁链观测模型以及电流控制模块分别采用了新电压模型和电压前馈补偿模块,保证了气隙磁链的恒定以及对电流的准确控制,为矢量控制的顺利实现奠定基础。对电机的准确建模是研究整个调速系统的关键之一,电机的建模采用的是Matlab提供的S-function函数与Smulink模块共同搭建。最后,在Matlab-Smulink中搭建核心模块以及矢量控制仿真框图,在对系统稳态仿真分析中可验证本文搭建的仿真模型和矢量控制的准确性。对仿真结果的分析可知,电机调速控制符合空气压缩机的稳定运行要求,能够实现变转速调节达到节能目的。更多还原

【Abstract】 Along with the rapid development of chemisty、colliery petroleum and metallurgy industry,etc.The Centrifugal Compressor is one of the important components in large enterprise of these industry,while it is the largest energy consumption facility in the grid. So the research of energy-saving method of the Centrifugal Compressor is very important. The enterprises carry out major energy-saving technological renovation of The Centrifugal Compressor in succession in recent years.Quest for the energy-saving method in order to reduce costs.The aim of this thesis is mostly in The Centrifugal Compressor energy-saving,the demands on the pressure and flow of air vary with the actual situation.So departing form the operating condition points will be appeared. Then the operating conditing must be changed in order to achieve actual situation.This paper analyzes the method of adjust Centrifugal compressor, with reference to characteristic curve of Centrifugal Compressor itself and it cooperates with distribution system. At present, there are three means to adjust Centrifugal compressor:throttle adjustment, changing centrifugal element adjustmen and changing rotate speed adjustment. The third method is claimed economical of all adjustment method.The change in the speed of Centrifugal Compressor by changing the speed of drive motor.Big power electrical synchromotor motor (it called ESM for short) is reported in this paper. The variable frequency device is used for the ESM speed adjustment. The most widely-used variable frequency device in every industry are vector control (VC) and direct torque control (DTC). Analyzes the load performance of Centrifugal Compressor, compared with direct torque control the main advantage of vector control is that good stability, high control accuracy, large capacity of frequency converter etc..So the vector control is used for speed control of ESM.This paper adopts gap motor flux oriented vector control, which can make the control performance of A.C. ESM is similar to D.C. machine.The controlling difficulty is simplify to obtain better control results. In order to guarantee the consrant gap motor flux and current control accurately, a new voltage model is used for torque observation and feedforward supply voltage model is used for current control in control system. This makes good groundwork for vector control.The kye part of drive system is to establish the model of ESM accurately. The simulation model of ESM and other of nuclear module of vector control system are built using Matlab/Simulink toolbox and S-function. The accuracy in the simulation model and the vector control has been verified by the analysis of system steady simulation. The analysis of the simulation results shows that the speed control theory can compliy to Centrifugal Compressor requirements and can work stably at different loading.更多还原