Medição de deslocamento utilizando um transformador diferencial variável linear baseada em técnicas de estimação.

Abstract

The Linear Variable Differential Transformer (LVDT) is a displacement sensor, used for linear displacement measurements. The displacement of the LVDT core varies the mutual inductance between the primary and secondaries coils, consequently, there is a voltage in the secondary coils, proportional to this displacement. The conditioning of this signal is used to compatibility of the data acquisition system. A commercial LVDT is sold together with a signal conditioner, being this proper system manufacturer. The system is calibrated by manufacturer and so, used by user. Many techniques have been proposed for signal conditioning LVDT. In this dissertation, presents for extracting of the displacement signal from the LVDT sensor, the use a model based system identification technique. The LVDT mathematical model is obtained through application Voltage Kirchoff’s law, to the equivalent electrical circuit. To parameter estimation of the LVDT is used the time-continuous model. Carry out the analysis of parametric sensibility in the time-continuous model from LVDT. The estimation algorithms used in this dissertation are least squares criterion and its recursive version. Through the development of two methods, that utilize the parameters of LVDT‘s model, as a displacement function, estimate the displacement signal from its core. The technique proposed is valued at numerical simulation. Finally, the technique is valued at through experiments, where carry out a similar analysis to the simulation results, which shows the viability the concept this implementation.