Development and investigation of the linear displacement sensor

Представлены результаты разработки и практической реализации индуктивного датчика линейного перемещения для систем гидропривода аэрокосмической отрасли. На основе результатов проектных расчетов датчика при различной конфигурации и геометрических размерах его обмоток выбран вариант с трехступенчатым распределением вторичных обмоток и получены характеристики датчика, не уступающие его известным аналогам.Purpose. Presentation of the results of development and practical implementation of an inductive linear displacement sensor (linear variable differential transformer LVDT) for hydraulics systems of the aerospace industry. Methodology. Calculations of three-dimensional magnetic fields are carried out with the finite elements method by JMAG program. The solution of the differential equations connecting the input voltage, current, magnetic flux and EMF of the windings is performed by numerical integration. Results. As a result of calculations, the sensor configuration, embodied in the model DLP-80, was obtained. Tests of the prototype model of the DLP-80 sensor confirmed the principle workability of the adopted design and design solutions in its development. Originality. The use of three-dimensional field models allows to make an accurate calculation of the sensor's magnetic field, taking into account the edge effects on its characteristics. As a result of the calculations, a variant with a three-stage distribution of the secondary windings and their overlapping in the region of the zero position of the moving part was chosen, which made it possible to increase the accuracy of the sensor. Practical value. The developed sensor DLP-80 in its technical characteristics is superior to the foreign sensor LDT-6522, which is close to the measurement range, and when the anchor is moved by ± 65 mm, the nonlinearity of the output characteristic reaches 3,5%. While in the developed sensor DLP-80 the maximum value of nonlinearity of the output characteristic is 0,7%. In addition, the volume of the sensor LDT-6522 and its mass are one third larger than the volume and mass of the DLP-80 sensor with a significantly higher energy consumption of the LDT-6522 sensor from the power source