直线压缩机控制系统的开发

【作者】 崔丽娜；

【导师】 郑水英；

【作者基本信息】 浙江大学 ， 化工过程机械， 2005， 硕士

【摘要】 随着压缩机技术的不断发展,在民用化方面,越来越多采用直线压缩机作为制冷机构。与传统的旋转电机驱动的往复式压缩机不同,新型的直线压缩机采用直接驱动技术,利用直线电机驱动压缩机活塞在气缸内作往复直线运动。具有结构简单、不需要曲柄连杆机构、机械效率高、易实现无油润滑等优点。如何对其进行有效合理的控制,是直线压缩机民用化研究的重要方面。本文在总结了国内外对直线压缩机控制系统研究工作的基础上,确立了本文的研究目标:一是通过对直线压缩机的特性分析,找到切实可行的直线压缩机控制系统的控制方案;二是在分析系统控制方案和控制目标的基础上,开发一套基于动圈型直线压缩机的电压控制系统。本文结合动力学、电磁学、电工电子学理论以及数据采集技术,着重开展了以下几个方面的工作: 1.运用Newmark积分法,对直线压缩机的机械和电磁系统求解,分析电容、活塞背压和导通角对活塞运动的影响,提出了直线压缩机的电压控制方案:以直线电机替代位移传感器,以电压作为控制对象,采用可控硅调压技术,利用PIC单片机控制可控硅的导通角,调节输入活塞线圈的电压,实现对活塞的行程、余隙和平衡位置的控制。 2.在理论计算的基础上,选取了正负半周可控硅均有导通并且过零自动关断的输入电压波形,开发了一套基于可控硅触发技术的PIC单片机控制系统,包括:同步脉冲电路、人机接口电路、导通角显示电路、隔离电路、放大电路和触发电路。实现了双向可控硅的可靠触发和对其导通角的控制。 3.将开发的电压控制系统与电磁动圈型直线压缩机样机进行联机实验,利用AD卡和计算机来进行实验数据的采集。从电路可靠性、电容、导通角对活塞行程和平衡位置的影响四个方面进行了实验研究和数据分析。实验结果与理论分析结果基本一致,为今后控制系统的研发工作奠定了基础。更多还原

【Abstract】 With the development of compressor technology, more and more linear compressors have been used in domestic aspects. Linear compressor is characteristic with its high efficiency, without crank-guide mechanism, easy to fulfill oil-less lubrication and the piston is driven by the linear motor directly. In order to further linear compressor research in domestic area, it’s important to find and develop a kind of control system for this type of compressor to make it running reliable with lower power loss. The thesis emphases on the control scheme analyze to design a control system and realize it to the experiment of the prototype linear compressor.In the thesis, the linear compressor control system is studied. Based on summarizing the literatures about linear compressor control system and model calculating, the author advances a voltage control system. In this system, linear motor is used to instead of the displacement sensor and input voltage is the controlled variable. In voltage modulation field, Triac has its advantages. So using PIC single-chip generates trigger pulse to control the Triac so that make it possible to control the piston’s displacement, average position and the flow rate of the mass. The control circuit is composed of synchronous pulse circuit, display circuit, trigger circuit, amplifier circuit, optical isolator circuit.In the experiment research, using the designed control system to modulate the wire input voltage. Analyzing the influence of the capacitor, how the voltage changes do to the piston displacement and average position. According to the experiment results, the influence of the four aspects to the system is similar with the calculating results.更多还原