【摘要】 基于SiC材料电致发光强度随电场强度增大而增强的特性,提出了一种在线测量发电机定子线圈端部SiC防晕涂层表面电场分布的新方法.该方法利用绝缘塑料光纤作为受光探头,避免了探头接触防晕涂层表面时引起该处电场畸变的问题.测量装置主要由光电转换、信号放大、信号处理单元组成.SiC防晕涂层特定点处电致发光信号波的峰-峰值Vp-p与该处电场强度E之间呈对数关系.将此测量方法用于1级和3级SiC防晕涂层,实际测量所得防晕涂层各点的电场强度值与理论计算值符合较好,误差均能控制在0.05以内,说明该方法准确度较高.更多还原

【Abstract】 The property that SiC electroluminescent intensity is enhanced with an increase of electric field motivates to propose a novel method for online detection of surface electric field distribution in the SiC stress-grading coating.The electric field distortion on the measurement spots is minimized by the insulated plastic optical fibre as the probe collects the electroluminescence of the SiC stress-grading coating.The self-designed measuring system primarily contains optical-(electrical) converter,signal amplifier and signal processing unit.The relation between the peak-peak values of the electroluminescence signal and the electric field of special spots of the stress-grading coating follows the logarithm law.When the method is applied to one and three orders SiC stress-grading coating,the measured values agree well with the calculated ones on the various spots,indicating the accuracy and reliability of this method.更多还原