计及边缘效应的变面积型圆柱面电容式角位移传感器的输出特性

Output Characteristics of Variable Area Cylindrical Surface Capacitive Angular Displacement Sensor Considering Edge Effect

为了研究计及边缘效应的变面积型圆柱面电容式角位移传感器的输出特性,将保角变换法、格林函数法和计算机数值模拟相结合,讨论变面积型圆柱面电容角位移传感器的电场,给出其电容量的表达式,绘制出该传感器电容量与极板旋转角度之间的变化曲线,分析影响该传感器线性度及灵敏度的因素,并指出改善该传感器输出特性的途径。数值模拟结果表明,在传感器的外极板所对应的圆心角等于内极板的情况下,增大圆心角的数值,减小两极板半径差和两块外极板的间隙,可使其同时具有较高的线性度、灵敏度和较大的测量范围。由于在讨论时计及了该传感器极板的横向边缘效应,故研究结果具有较高的精确度。

In order to study the output characteristics of variable area cylindrical surface capacitive angular displacement sensor considering edge effect,the electric field of variable area column panel capacitive angular displacement sensor is discussed by combining conformal transformation method,Green’s function method and computer numerical simulation,the expression of its capacitance is given,and the variation curve between the capacitance of the sensor and the rotation angle of the plate is drawn,the factors affecting the linearity and sensitivity of the sensor are analyzed,and the ways to improve the output performance of the sensor are pointed out.The numerical simulation results show that when the center angle corresponding to the outer plate of the sensor is equal to the inner plate,increasing the value of the center angle and reducing the radius difference between the two plates and the gap between the two outer plates can make it have high linearity,sensitivity and large measurement range at the same time.Because the lateral edge effect of the sensor plate is taken into account in the discussion,the research results have high accuracy.