【摘要】 变压器油中溶解气体的检测及分析是运行电力变压器故障诊断最有效的方法之一。气体光声光谱检测技术能很好地应用于气体检测,气体压强对光声光谱检测有重要影响。论文从理论上推导出气体压强与气体吸收系数、谐振频率、光声池品质因素、池常数及气体光声电信号的函数关系。以构建的可调谐光声光谱装置对变压器油中主要故障特征气体C2H2进行实验,验证了上述函数关系的正确性,得到在气体吸收未发生饱和效应时,C2H2光声电信号与气体压强的函数关系:当0<P<75k Pa时,光声电信号近似与气体压强P1.5成线性关系;而当75k Pa<P<100k Pa时,光声电信号近似与气体压强P成线性关系。结合吸收谱线增宽及光声电信号变化规律,确定C2H2的谱线6 578.58cm?1最佳光声检测压强为75k Pa,理论及实验结果为进一步完善油中溶解气体光声光谱在线监测提供了技术支撑。更多还原

【Abstract】 Dissolved gas analysis(DGA) method is one of the most effective means in fault diagnosis of power transformer. Gas photoacoustic spectroscopy(PAS) can be well applied in gas detection. The effect of gas pressure on the photoacoustic spectroscopy detection is significant. Functional relations between gas pressure and gas absorption coefficient, resonant frequency, quality factor, photoacoustic cell constant and PA voltage(PAV) signal are derived theoretically in this paper. Based on the constructed tunable experimental setup, experimental detection of the acetylene dissolved in transformer oil was done. The experimental results show the correctness of the functional relations above and that PAV signal has a good linear dependence on the 1.5th root of pressure P(0<P<75k Pa) and the square root of P(75k Pa<P<100k Pa) when without gas absorption saturation effect. Taking consideration of absorption line broadening and the change rule of PAV signal, the best gas pressure for the photoacoustic spectroscopy detection of acetylene absorption line 6 578.58cm?1 is 75 k Pa. The theoretical and experimental results provide technical support for further improvement in photoacoustic spectroscopy on-line monitoring for oil gas.更多还原