Linear Motor

A linear motor is an electric motor whose stator and rotor have been unrolled flat, so that instead of producing rotational torque it produces a linear force along its own length, working on the same Lorentz force principle as a rotary motor, with the force it generates proportional to the current and the magnetic field. Linear synchronous motors power maglev systems such as the Shanghai maglev train, while linear induction motors, which use a three phase winding on one side facing a passive conductor plate on the other, are common in industrial automation, a market valued at roughly 1.8 billion dollars in 2024. Designs split into low acceleration machines, suited to maglev trains and other ground transportation, and high acceleration machines built for very rapid acceleration over short distances, such as coilguns. Unlike a conventional rotary motor, which forms a continuous loop, a linear motor has defined physical ends, a structural difference that follows directly from unrolling its magnetic circuit.