Zero-power control of flux-path control magnetic suspension system with flux-interrupting plates

The feasibility of zero-power control in flux-path control magnetic suspension is discussed. In the flux-path control magnetic suspension system, ferromagnetic control plates are inserted between a permanent magnet (magnetic source) and a floator and moved to vary the flux from the magnetic source to the floator. The zero-power control has been applied in active magnetic suspension with a DC electromagnet. In the zero-power controlled system, the control current was kept virtually zero in the steady states. The applicability of the zero-power control to the flux-path control magnetic suspension is discussed in this paper. The conditions required to achieve the zero-power control is presented in an analytical form. Experiments are carried in a fabricated apparatus to certify the theoretical predictions.