Research And Design On Computer Control Calibration System With Gas Flow Standard Device

At present, there are a lot of works on gas flow meter calibration in production manufacture and use situation. So a gas flow standard device should be not only enough in accuracy and reliability, but also it should be efficient. According to this industrial situation, a computer control calibration system with gas flow standard device by the master meter method is researched and designed. Based on the preferable accuracy, the system can enhance the calibration efficiency in production manufacture process extremely.Firstly, a ventilator's convert-frequency technology is applied in the systems, which improves the flow control accuracy and stability. Comparing with the gas flow standard bell device, it not only reduces the massive mechanical organizations, the design difficulty and the device volume, but also avoids the massive electrical energies waste adjusting the flow caused by valves. Secondly, the application of synchronous pulse counting method in master or field flow meter's data collection process ensures that the period of time between two signals keep synchronous with flow pulses, when industrial PC sends out the start or end calibration signals. At the same time, pulse interpolation algorithm can work out the accurate pulses rapidly, so the calibration time and errors are both reduced. Thirdly, in gas flow stability control process, with the integral separation limits, the integral separation PID algorithm is used to avoid integral saturated phenomenon caused by an oversized initial error. Now, the computer control calibration system with gas flow standard device by the master meter method is in test run condition. With the characteristic of high efficiency, small cost and high degree automation, this system will suit the flow meter production manufacture enterprise.