Design And Study Of The Computer Control System For Fermentation Process

The thesis, design and study of the computer control system for fermentation process, is a part of the project, application environment study of antibiotic fermentation process modeling and controlling which is sponsored by natural science fund of Tianjin City.In this thesis, project designing and process realizing of microorganism fermentation control system are described. Through technically modifying of old fermentor which mainly consists of conventional instrument and whose capacity is 14L, the fermentation control system based on computer is constructed and completed, thus data acquisition and real control of fermentation process was realized by PC, all of these provide hardware platform for fermentation process modelling and optimization control.The control system includes two parts: hardware design and software design. In the part of hardware design, the design that control mode can be switched freely between automatic control and manual control was employed. We restored the fermentor whose function was partly out of work to its original manual control status and made it work normally, based on this the fermentation device was reconstructed recoverably. Programmable Logic Controller (PLC) as host computer directly controls fermentor, personal computer (PC) as slave computer acquires and manages data, they communicate through serial port, thereby the system achieves autocontrol function. Software design makes up of PLC and PC program, PLC program accomplishes sampling, managing and handling fermentation data, and PC program accomplishes the storage, complex operation and supervise-control of fermentation data. The communication between PLC and PC follows the communication protocol, which is developed by ourselves.The control system can complete all the functions of original control in manual mode, and when switched to automation mode, the system can automatically realizes the environment control of fermentor without man's intervention. Meanwhile, the system completes data acquisition, data processing, real-time display, and report forms printing, all of these make the premise for optimization control of fermentation process.