| In recent years along with the microorganism drugs manufacture's development as well as experimental facility's import to the environment request's enhancement, the P3 laboratory technical level has been promoted greatly. Specially, the SARS virus's eruption, the country expands the investment to the microorganism and the viral laboratory. The newly built one batch of high grade P3 level laboratory has realized the experiment environment intellectualized monitoring. How to well control the P3 laboratory's technical specification is a new task, which we should face. The biological safety protection third-level laboratory is strict to the negative pressure and pressure gradient's request. The system must act according to air blower's breakdown situation, personnel's turnover as well as the security cabinet's starts and stops, which may cause the perturbation to the indoor negative pressure. The system must also carry on the real-time monitoring to the sensor and actuator's condition, and send out the acousto-optics alarm when each accused parameter exceeds the allowed figure. This article has discussed the Distributed Control System and the Direct Digital Control system in the P3 laboratory synthesis application, the software system's constitution as well as the digital PID control technology application. The system has taken the method of air flow rate shifting to deal with pressure gradient sudden change, which is caused by laboratory gate opening. In order to serve this purpose, the automatic control system has carried on multi-spot signal gathering nearby the gate. It causes air flow rate shifting appropriate and reasonable, and it effectively alleviates the pressure gradient sudden change. The P3 laboratory's automatic control system, after the working and the debugging, has achieved the goal very well and obtained expert's affirmation. |
