ABSTRACT
A single-phase linear PM motor in tubular construction is presented in Figure 12.1. It was proposed [1] as a thermal engine valve actuator.
It contains
• A dual part somaloy passive mover • A tubular PMmade of 6-12 sectors to reduce the eddy current losses in the PMs due to the ac mmf of twin coil currents
• A stainless steel (shaft) coupled to the thermal engine valve The electromechanical device also contains two mechanical springs that
are not shown in Figure 12.1. The two mechanical springs act in opposite directions and their forces are in equilibriumwhen themover is in themiddle position. The magnetic force at zero current acts the mover so as to increase its displacement (Figure 12.2). This force has an unstable equilibrium point
Electric with MATLAB
FIGURE 12.1 Electro-valve linear PM actuator.
