摘要
目的研究余热回收系统中水循环路径,实现系统中四台水泵随压力变化而自动启停的控制并最终实现系统的自动控制.方法结合热冲压工艺对水的循环路径进行分析,通过得到的冷却循环系统的逻辑控制关系,分析压力影响因素.分析水泵的电气实现过程,利用VB对冷却循环系统的压力控制过程进行模拟.结果得到了根据流量变化可以改变液体压力,通过压力变化来控制水泵的开启.当压力高于0.48 MPa时,电控阀C1开启;当压力低于0.4 MPa时,水泵的开启还受到时间的限制,当前一台开启时间低于3 min时,水泵的启停情况不变.经过VB模拟证明,提出的控制方案是可靠的.结论根据压力变化可以实现冷却循环系统水的自动循环,根据逻辑控制过程来编订程序可以减少循环错误,节省大量时间,取得更大收益;同时利用压力控制来实现系统的自动控制的方法,可以广泛应用于其他相似过程控制的液体传输.
This paper studies the water cycle path in the waste heat recovery system. According to the condition of pressure control,the control method for 4 w ater pumps’ automatic start-stop based on the change of pressure can be obtained. At last,the automatic control of the system can be realized. In this paper,the w ater cycle path w as analyzed combining w ith hot stamping process,the logic control relation of cooling circulatory system could be obtained. From the analysis of pressure,the conclusion that changing flow can change liquid pressure could be obtained. So the w ater pumps’ start-stop can be controlled based on the change of pressure. Through the analysis of pressure on the w ater pump’ electrical control,the pressure control process can be emulated using VB. The results can be obtained. C1 is opened w hen pressure is higher than 0. 48 MPa. When pressure is low er than 0. 4MPa,the w ater pump’ start-stop is restricted by time. The w ater pump’ startstop w ould not be changed w hen the open time is less than 3 min. The Control scheme is reliable through VB simulation proof. According to the pressure change,automatic cycle of w ater can be achieved in cooling circulatory system. It can reduce loop errors,save much time and make greater rew ards on the basis of logic control process. The method using pressure control to realize the system auto-control can be w idely used in the similar process for liquid transport.
出处
《沈阳建筑大学学报(自然科学版)》
CAS
北大核心
2014年第2期323-328,共6页
Journal of Shenyang Jianzhu University:Natural Science
基金
国家科技支撑计划项目(2011BAJ02B0302)
关键词
余热回收系统
控制方案设计
压力控制
逻辑控制
waste heat recovery system
control program design
pressure control
logic control