Method for balancing the movement of mobile masses in a bi-linear electrodynamic motor

Abstract

The motion of the magnetized movable masses of a bilinear electrodynamic motor comprising two movable masses moving in opposite senses parallel to the axis (x-x) of the motor is balanced. At least one first magnetic sensor and at least one second magnetic sensor are provided which are able to deliver respectively a first electrical signal (s(t)) and a second electrical signal (s(t)) respectively representative of the motion of a first and of a second movable mass. An error signal (Δs(t)) equal to the difference between the said first (s(t)) and second (s(t)) electrical signals is recorded. A harmonic analysis of the error signal performed. A sinusoidal excitation signal (e(t)) at a given frequency fis applied to the first movable mass. N successive excitation signals (e(t)) are iteratively applied to the second movable mass, an excitation signal of rank n (0≦n≦N−1) being equal to a Fourier series of order n of fundamental frequency f, the term of order n of the said series being adjusted in amplitude and in phase so as to minimize the component at the frequency n·fof the error signal. The excitation signal (e(t)) of rank N−1 is taken as excitation signal for the second movable mass.