Boldea I. Linear Electric Machines, Drives, and MAGLEVs Handbook 2ed 2023

Textbook in PDF format

Linear motion is richly present in various industries, from direct electric propulsion in urban and interurban people movers on wheels or on magnetic “cushions” (MAGLEVs) to indoor transport of goods (conveyors, etc.), through plunger solenoids (to open hotel doors and as electromagnetic power switches), to compressor drives by linear oscillatory permanent magnet (PM) motors, smart phones integrated microphone and loudspeakers, and controlled vehicles’ suspension, etc. Besides the traditional rotary motor drives with mechanical transmissions, which mean friction limitations (weather dependent) in traction (heavy vehicles), more losses, positioning errors (backlash) in the process, and higher maintenance costs to handle them, linear motion in industry by direct electromagnetic forces is free of friction limitations for traction, free of mechanical transmission, and thus more efficient, with less maintenance cost and fewer positioning errors (backlash). This explains why they are used in so many applications already since the dramatic advancement of power electronics and digital control in the last four decades