Temperature Control Of Photobioreactor Based On Fuzzy Control

Large-scale culture is the most critical problem in microalgae biotechnology,because there are many factors that affect its growth in the process of microalgae culture,of which temperature is an important factor affecting the growth of microalgae.The optical bioreactor temperature system is a complex closed-loop control system with multi-input and multi-output,and the traditional PID control effect is not good.With the improvement of Controller and the further research of intelligent algorithm in modern science and technology,the application of intelligent algorithm to optical bioreactor temperature control system has been more and more supported.Photobioreactor is the core device for photoautotrophic culture.Large-scale cultivation is the most critical problem in microalgae biotechnology,because there are many factors that affect its growth in the process of microalgae culture.In these factors,temperature is an important factor affecting the growth of microalgae.However,the temperature system of photobioreactor is a complex closed-loop control system with multi-input and multi-output,and the traditional PID control is uneffective.With the development of modern science and technology and the further research of intelligent algorithm,the application of intelligent algorithm in temperature control system of photobioreactor has gained more and more support.On the basis of our predecessors,the temperature of photobioreactor is taken as the research object.The main contents are as follows:Firstly,the types and characteristics of photobioreactor is briefly introduced.By analyzing the characteristics of different types of photobioreactor,the counter-flow airlift cylindrical photobioreactor is designed and its partial systems were introduced in detail.The temperature control model is established by its own mechanism,and finally the ideal temperature model can be selected as transport delay and first order inertia time,which lays a foundation for the later system simulation.Secondly,aiming at the problem of poor regulation performance of conventional PID in the process of temperature control,based on the traditional PID and fuzzy control theory,combining the advantages of both,the specific design steps of the fuzzy PID controller are given.Thirdly,Because the fuzzy PID needs to use the experience to establish the membership function and fuzzy control rules,an improved and real-coded genetic algorithm is proposed to optimize membership function and fuzzy control rules simultaneously.A fuzzy PID controller based on improved genetic algorithm optimization is designed.Finally,the traditional PID control,conventional fuzzy control,fuzzy PID control and genetic algorithm optimized fuzzy PID are simulated by using MATLAB software.The control defects of traditional PID and fuzzy control are verified by simulation.Meanwhile,the experimental results,through the comparison experiment,show that the performance of the fuzzy PID controller based on genetic algorithm optimization has been greatly improved,and it is suitable for the temperature control system of photobioreactor.