【摘要】 光干涉甲烷检测器具有稳定可靠性强、测量范围宽等优点,但现有设备都采用人工读数方式,自动化程度低,不能连接到煤矿监控系统。针对该问题,提出了一种基于测量干涉条纹光强的改进方法。通过改进光路设计,保证了甲烷体积分数与光强变化之间对应关系的惟一性。使用光电元件采集干涉条纹,根据干涉条纹的光强变化得到甲烷体积分数。针对光干涉甲烷检测器的零点受外界环境因素影响而发生漂移的问题,首先通过理论分析得到了外界气压与测量误差之间的关系模型,并使用该模型对外界气压变化进行补偿;然后由实验得到温度与测量误差之间的关系,采用线性插值方法建立温度补偿模型。最后通过精度实验、压强实验、温度实验和长期稳定性实验验证了所设计的补偿模型的有效性和系统的稳定性。更多还原

【Abstract】 The light interference methane detector has many advantages,such as high stability,wide measurement range,etc. However,the artificial reading and low level of automation make it no communication ability with monitoring system. To solve this problem,the authors made an improvement based on the measurement of interferogram intensity. The optical configuration was modified to guarantee the one-to-one relationship between the intensity of interferogram and the methane volume fraction. The authors used photoelectric elements to capture the interferogram and calculated the methane volume fraction with the variation of interferogram intensity. Given that the zero-drift error was affected by environmental factors,the authors modeled the relationship between pressure and measurement error by theoretical analysis,which was used to compensate the measurement error. Then the relationship between temperature and measurement error was experimentally determined. The authors thus obtained the temperature compensation model by linear interpolation. The effectiveness of compensation models and the stability of designed sys-tem were verified by accuracy test,pneumatic test,temperature test and long-term stability test.更多还原