ANALYTICAL STUDY OF A LINEAR VARIABLE DIFFERENTIAL TRANSFORMER TRANSDUCER

A theory to explain the functioning of a linear variable differential transformer (LVDT) transducer has been developed in this work. By using the magnetic vector potential A in cylindrical coordinates for a thin circular conductor carrying a current I, the expressions for the self- and mutual inductances involved in the theory were obtained. Kirchhoff laws for alternating currents were used to obtain an expression for the transfer function or gain \v(o)/v(i)\ of the transducer. Then, the variation of gain with displacement theta at a fixed frequency, as well as the dependence of gain with frequency at a fixed displacement theta are examined. Finally, it is concluded that the results here found correspond to a self-compensated LVDT. (C) 1995 American Institute of Physics.