Linear Variable Differential Transformer in Harsh Environments - A Displacement and Thermal Study

Linear variable differential transformers (LVDT) are high precision linear position sensors and capable of measuring position up to one meter. Especially in environments with high temperatures and temperature variations, the core material used, ferritic or non-ferritic, is critical. In this paper we present simulations and comparative measurements to interpret the dependency of LVDTs. We analyse the performance of the LVDT with respect to changes in the excitation signal, as well as uniform and non-uniform heating of the LVDT. The simulation model presented can be used to model the sensor behavior and reproduce the dependencies of the output voltages. The results show that the behavior of the sensor varies depending on the position of the core. This makes compensation measures difficult.