Linear electrodynamic-type motor, cryocooler including such a motor and method implementing such a motor

A linear electrodynamic-type motor, for compressing a fluid circulating in a cryocooler notably using a Stirling cycle, the motor comprising:

• at least one power-supply circuit adapted to deliver an AC power-supply current at an AC power-supply voltage,
• at least one movable mass, such as a piston, adopting a translational movement between a first position and a second position in which a respective one of the at least one movable mass can compress the fluid;
• and
• at least one induction coil connected to the power-supply circuit and arranged so as to transmit the translational movement to a respective one of the at least one removable mass;
• at least one secondary circuit arranged to be connected to the terminals of at least one induction coil;
• and
• at least one switching device arranged so as to selectively connect the secondary circuit to at least one induction coil, wherein:
• the secondary circuit comprises at least one compensation component adapted for producing a phase shift between said AC power-supply voltage and said AC power-supply current so as to reduce a phase difference that an inductance of the induction coil produces between said AC power-supply voltage and said AC power-supply current;
• each at least one switching device has a first position, in which the respective secondary circuit is connected to the respective induction coil;
• the or each switching device has a second position, in which the respective secondary circuit is disconnected from the respective induction coil;
• the or each switching device is arranged so that, in the first position, the respective power-supply circuit is disconnected from the respective induction coil;
• and
• the or each switching device is arranged so that, in the second position, the respective power-supply circuit is connected to the respective induction coil.