A Position Sensor With Novel Configuration of Linear Variable Differential Transformer

This paper presents a position sensor \nbased on a novel configuration of linear variable \ndifferential transformer. Design and optimization of the \nposition sensor using finite element method are \npresented. The measurements are also conducted to \nvalidate experimentally the sensor performance. The \nsensor has short air core coils and long magnetic \narmatures. The axis of the rectangular excitation coil and\ntwo antiserially connected rectangular pick up coils is \nperpendicular to the motion direction of the position \nsensor. The coils are located between two parallel silicon \nsteel laminations serving as the armatures. The position \nsensor is optimized with compromise between minimization of nonlinearity error and maximum sensitivity. The main \nadvantage of the proposed position sensor is the small ratio of coils dimensions to the working range. The position \nsensor is operated for excitation frequencies of 500 Hz, 1000 Hz, and 2000 Hz. The maximum nonlinearity error is less \nthan 1.5% for the theoretical results and it is less than 2% for the measured results in ±90 mm position range.