基于Pockels电光效应的电压方向测量

Measurement of voltage direction based on Pockels electro-optic effect

为了实现在光学电压互感器中电压方向的测量,利用Pockels效应和偏振光理论进行理论分析和实验验证,提出了一种基于Pockels效应的电压方向测量方法,得到不同方向的电压与出射光偏振态、光传播方向之间的关系。结果表明,当施加的电压值为100 V时,迎着光观测,透射光的长轴和短轴分别位于空间角度20°和110°,再通过λ/4波片后的光偏振方向位于坐标的二、四象限,可判断透射光是右旋椭圆偏振光,电压方向沿光传播方向;长轴和短轴分别位于角度130°和40°的透射光通过λ/4波片后的光偏振方向位于一、三象限,则透射光是左旋椭圆偏振光,电压方向则沿光传播的相反方向。实验结果与理论分析相符,可指导设计既能测量电压大小又能判断其方向的光学电压互感器。

To achieve measurement of voltage direction for optical voltage transformers,theoretical analysis and experimental verification were conducted by the Pockels effect and theory of polarized light,and a measuring method of voltage direction was presented based on the Pockels effect.The relation among different direction voltage,the state of light polarization and light propagating direction were obtained.The results show that,when the value of applied voltage is 100 V,observing toward light,the long and short axis of the transmitted light are located at the spatial angles of 20°and 110°,respectively,and the polarization direction of light passing through aλ/4 wave-plate is located in the second and fourth quadrants of the coordinates,which indicates that the transmitted light is right-lateral elliptically polarized light,the direction of voltage is along the light propagating direction.In addition,the spatial angles are 130°and 40°,and the polarization direction with aλ/4 wave-plate is located in the first and third quadrants,which indicates that the transmitted light is left-lateral elliptically polarized light,the direction of voltage is along the opposite direction of light propagation.The experimental results agree well with the theory,which can guide the design of optical voltage transformers that can measure the magnitude and direction of voltages.