Measurement And Control System Of The Piggery Environmental Factors Based On Field Bus

The piggery is a place of the commercial pigs activity. Only in suitable environment, can pigs be more productive and reduce the consumption of feed. Compared with developed country, pig industry is uncultured in our country. And the environmental problem of the piggery is one of major factors to cause this present condition. To reduce the negative influence of environment on pigs' production, in recent years, some environmental control technology concerning confined piggery is adopted. The advanced technology includes using lengthways ventilation and applying wet curtain lower temperature in summer. But in the light of present situation of environmental manmgenent in the piggery, they ignore the coupling relations between environmental factors, and most of facility is operated by hand or by mechanical and electrical mode. The level of automation is low and can't meet the need of modern management.The monitoring system designed in this article implements intelligent monitor and control of the temperature and humidity in the piggery. The hardware of the monitoring System mainly consists with the sensor, conditioning circuits, field bus, controller and actuator. The software realizes centralized monitoring and spot control functions of the piggery, using Modbus protocol to communicate between the main stations with the slave ones. Using the rich controls of VB6.0, I develop friendly and easy-to-use monitor screen. After the assembly and debugging system achieves desired objectives.Because the piggery environment is a big delay, nonlinear, multi-input and multi-output system, so it is impossible to build an accurate math model and it is difficult to get satisfying effect using common control algorithm. At the base of studying environmental factor which affects the growth of commercial pigs, and according to the actual condition of the system, this article proposes the control algorithm of fuzzy direct inference. Practical operation indicates the system realizes high-performance and safe monitoring procedure.The whole system which is used in Zhenjiang Xima Breading Husbandry Co., Ltd.make clear that it has friendly interface, convenient operation and comprehensive function. This system can enhance the stability of testing process, and improve the condition of environment in the piggery, and reduce the workload of feeder and controller. The system can be widely used in the large-scale and modern piggeries. Especially, in the current shortage of pork and descendion of scale in our country, the system has higher promotional value.