Abstract: A power supply system for a linear motor comprising a plurality of driving coils disposed along the track for a running body for generating a shifting magnetic field to drive the running body, power converter means for feeding the plurality of driving coils with electrical energy, a plurality of switches responsive to the movement of the running body for selectively electrically connecting each of the driving coils to the power converter means, a first reactive power controller continuously electrically connected to the power input side of the power converter means, and a second reactive power controller selectively electrically connected to the power input side of the power converter means in accordance with the movement of the running body, whereby the steady reactive-power is compensated for by the first reactive power controller and the reactive power which varies with the movement of the running body is compensated for by the second reactive power controller.