燃气发电机组空燃比控制系统设计.pdf

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自动化博览增刊
燃气发电机组空燃比控制系统设计
牟德强
胜利油田胜利动力机械集团有限公司,东营257032)
摘要:本系统空燃比的自动控制采用精确控制,做到超前和滞后双重控制,增强自动控制系统的
靠性。超前控制则根据CH4浓度调节主管道混合气中的燃气和空气进气量,使进入进气管中的混合气达
到空燃比的最佳范困之内。滞后控制则根据缸温控制,但采用单缸控制进气量,进而可单缸调缸温,降
低对机组功率的影响。同时采用西门子S7-200PI,C对现场进行控制,软件协议采用支持RS-485网络的
Modbusエ业通信协议,采用 Modbus通信协议实现了自由通信模式下工控机和西『门子S7-200PILC的串行
通信,实现了两级之间的实时通信,完成对燃气机组的空燃比控制,从而实现机组空燃比的最佳匹配,
自动控制机组的稳定运行。
关键词:空燃比自动控制 PLC Modbus通信
The design of Gas generator set air-fuel ratio control system
gang
Shengli Oil Field Shengli Power Machinery Group Co. Ltd Dongying 257032
Abstract Automatic control of the system using precision air-fuel ratio control to achieve the dual control of lead and lag, and
enhance the reliability of automatic control system. Advanced control regulation under the charge of Road CH4 concentration mixture of
gas and air into the air, so that eathing tube into the mixture of air-fuel ratio to achieve the hest range. Hysteresis control is still un
der the tank temperature control but control of the use of single-cylinder into the gas, which can be adjusted single-cylinder-cyl
inder temperature, reduee the impaet of power on the unit. At the same time, adopt Siemens 57-200P1C to be in progress to the
scene under the control of, the software agreement adopts to suppor network RS-485 Modbus industry communication agreement, has
adopt Modbus communication y agreement to have realized free communication pattern going off work charging machine and Siemens
S7-200 PL serial for communicating by letter, has realized the real time communicate by letter between two steps, the empty space
being completed to gas aircraft crew burns a ratio realizing aircraft crew empty space under the control of, thereby burning the best
mateh comparing stability of autocontrol aircraft crew works.
Key Words, Air-fuel ratio: Automatic control PLC: Modbus communication
进行双重控制的燃气发电机组控制系统,从而实现
1前言
机组空燃比的最佳匹配,自动控制机组的稳定运行。
随着燃气发电产业的不断发展,用户对燃气发
电机组的自动控制水平要求也越来越高,而国内的2正文
燃气发电机组自动控制系统都处在发展阶段,自动
2.1空燃比自动控制的实现方法
控制系统也不完善,基本都是根据单一条件的反馈
现在我国燃气发电机组空燃比的自动控制系统
来控制空燃比的,没有建立在机组运行时的综和参基本上是单一调节,控制不精确,常常导致机组运
数之上,因此,今后燃气发电机组的智能化控制将行不稳定。如果只是通过缸温控制,属于滞后控
是各燃气机企业竟争的重点。本文以PLC为基本控制,对于缸温突窜的情况不能自动及时调节,必须
制,在燃气发电机组的进气主管道安装燃气和空气手动调节才能恢复正常,而且由于做不到单缸调
均匀混合装置,设计出通过根据浓度和缸温对机组节,调节后功率将下降。另外,由于混合气混合时