Design Of The Self-regulated Smart Oxygen Meter For Fieldbus

Basing on the analysis and summaries of the development and tendency of the zirconia oxygen analyzer both at home and borad, this paper proposed a self-regulated smart oxygen analyer for field bus by using the new systemlevel microprocessor, the advanced algorithems of self-regulating and temperature-controlling, the techniques of computer software and hardware designing as well as the field bus knowledge. The ocygen amount in the boiler flue gas, a significant parameter in combustion optimization analysis, can be quite meaningful for the efficiency of the boiler and its economic benefits under a real-time monitoring. Thus, the oxgen analyzer mentioned above is aiming at measuring this importtant paramrter in the gas route channels. In the designing process, we use the mult-functional MC9S12XEP100MAL chip as the central processing unit, which greatly simplifies the peripheral circuit’s struture and enhances the stability and reliability of the system as a whole; also, the intelligent and modular methods make it very convenient to expand the functions or upgrade the software and hardware. When it comes to the temperature controlling, this analyzer follows the core mentality of dynamic measuring ranges and variable-element PI controlling method for PWM(Pulse Width Modulation), which increase the regulating accuracy to a great extent. By breaking through the traditional instrumenr calibration ideas, we use a calibrating method----the Slope Coefficient K based calibration to make up the disadvataged that ecist in the current method. Meanwhile, the measuring errors of the analyzer are decreased and its calibration function is more intelligent accordingly. In order to guarantee the reliability, the openness and its communicatting functions, the technique of CAN field bus is firstly applied in the designing of the oxgen analyzer. Compared whit traditional meters, this analyzer is so powerful in a variety of ways, such as measuring, real-time monitoring, self-regulating, digital filtering, intelligent processing and system security. And this CAN field bus based analyzer’s performances in human-machine interaction, data communication and large real-time storage are much more than what a regular meter can do.