磁光式光电电流互感器幅值精确度的研究

Study of measurement accuracy of magneto optical current transducer

为了使磁光式光电电流互感器实用化，研究了影响它精确度的主要因素：温度和应力。从光源波长与温度及驱动电流的关系中得出了应对光源、光电转换和关键电子线路进行温度控制的结论，否定了通常采用的利用反馈的方法改变驱动电流来保持光强恒定的作法。发展了一种组装应力很小的，可以减少双折射效应的传感头组装方法。研制成的样机进行了温度测试，在－３０～７０℃的温度范围内，它的测量误差小于±０．３％，达到０．３级电流互感器的精确度。

The effects of temperature and stress on the measurement accuracy of magneto optical current transducer were deeply studied, in order to promote its practical application. The temperature control of the light emitting diode (LED), photodiode PIN and electronic circuit is preferable, according to the fact that the wavelength of LED depends on its temperature and driven current. The method to maintain the intensity of LED by adjusting driven current is proved to be improper. A unique assembling method of sensor head with less assembling caused birefringence is developed. The accuracy of a developed bulk type magneto optical current transducer is within ±0.3 % at a temperature range from -30 ℃ to 70 ℃.