Design Of Inverse Decoupling Control System For The Process Of Animal Cells Suspension Culture

With the development of modern biotechnology,cell engineering plays an increasingly important role in national economy and social life.Animal cell culture,as one of the most important cell engineering categories,has important value in the production of vaccines and antibodies.Suspension culture has the advantages of rapid cell proliferation and high production efficiency.It is especially suitable for large-scale production and has become the mainstream technology in the current industrial production of vaccines.The biopharmaceutical industry,which is based on animal cell suspension culture technology,has developed rapidly and achieved great economic and social benefits.The process of animal cell culture is different from the general industrial process.It is a nonlinear,multi-variable input-output,strong coupling biological reaction process,and involves cell growth and reproduction,the mechanism is very complex.One of the most important directions in the process control of animal cell culture is the study of linearization decoupling control,that is,the nonlinear system such as the process of animal cell culture is transformed into a linear system,and at the same time,the purpose of decoupling is achieved.The control problem of multivariable strongly coupled nonlinear systems is simplified to that of linear systems.In this paper,the inverse system method is used to realize the linearization and decoupling of the animal cell culture process.Based on the deep analysis of the internal reaction mechanism of the actual process,a kinetic model reflecting the animal cell culture process is established and the reversibility of the system is analyzed.In view of the difficulty of solving the analytical inverse of the controlled system,the nonlinear identification ability of the neural network is used to construct the inverse system equation of the controlled system.It is necessary to excite the controlled system sufficiently,collect the sample data,and ensure the accuracy of numerical differential solution.The high precision algorithm of seven point derivation is used to preprocess the data,then the neural network is trained to construct the inverse system after normalized processing,and then it is used to compensate the controlled system,so that the composite system becomes linear or nearly linear in a wide range.Finally,the linearization and decoupling of the controlled system are realized.In order to realize the high performance control of the decoupled subsystem,the fuzzy PID controller is designed as the additional controller to realize the closed-loop control of the system,and the simulation using MATLAB is carried out,which verifies the feasibility of the control strategy adopted in this paper.Compared with the control effect of traditional PID,the advantages of the designed fuzzy PID controller are: small overshoot,short adjustment time and fast response speed.In order to effectively monitor the process of animal cell suspension culture,the digital control system of animal cell suspension culture process is designed.The embedded microprocessor S3C2410 A based on ARM9 kernel is used as the operation control unit in the lower computer control system.The related hardware circuit and software program are designed.The interface of the upper computer monitoring system is developed on QT/Embedded platform.It has the functions of real-time data display,alarm sending and recording,report form generation and printing,operation control algorithm and so on.The interface is intuitive and friendly,which is convenient for operator to analyze and control the training process.