Abstract: When load reduced to a certain degree,compressor will produce dramatic surge phenomena.This will seriously damage the machine and lead to a serious consequence.The purpose of this paper is to simulate the surging phenomena and its control in rich gas compressor of fluid catalytic cracking unit.The surge will happen in a short time,and its operation step length is thousands of times different from catalytic cracking running time,so it will simulate in two different time scales.First,the compressor model applying in active control is established by using user unit model extension.In order to overcome the consumption in steady areas brought by active actuator,switching control scheme designed that compressor implements active control in surge region while compressor without active control in stable region only applying PID control can satisfy the technological requirements.Finally,the scheme is used in the dual time scales simulation.The whole process validates the effectiveness of the proposed scheme and proves that it can both solve the problem of compressor could not work in high performance area in the traditional anti-surge passive control and resolve the increasing of the energy consumption brought by active actuator.

Key words: compressor, FCCU, surge control of compressor, dynamic simulation, dual time scales

摘要： 压缩机工作时,当负荷降低到一定程度时,会产生剧烈的喘振现象。喘振会严重损坏机体,产生严重后果。旨在模拟催化裂化富气压缩机喘振及其控制,由于喘振产生的时间很短,与催化裂化运行时间相差数千倍,所以要在两个不同尺度时间下进行模拟。本文基于压缩系统机理模型在UniSim中开发了一个适用于压缩机主动控制的模型,同时为克服主动执行机构在压缩机稳定区带来的附加损耗,针对压缩机喘振现象设计了切换控制方案,在压缩机喘振时采用主动控制进行喘振控制,而在稳定工况点则取消主动控制作用。最后将该方案应用于压缩机双时间尺度模拟中,并从不同的时间尺度下对比了喘振控制对催化裂化过程的影响,整个过程验证了方案的有效性以及该方案可以同时解决防喘振控制使压缩机无法在高性能区工作和主动执行机构所带来的能耗增加的问题。

关键词: 压缩机, 催化裂化, 喘振控制, 动态模拟, 双时间尺度