A Novel Secondary for Reducing Thrust Ripple of Long Primary Double Sided Linear Induction Machine Used in Microgravity Experimental Chamber Launch System

Based on the electromagnetic field theory, the distribution of thrust density along the longitudinal direction of long primary double-sided linear induction machine (DLIM) with plates secondary is studied. Then a novel wedge type secondary for long primary DLIM is proposed to reduce the ripple of thrust and acceleration. The influence of new secondary parameters on DLIM performance is researched, and the characteristics of thrust and its ripple of plate secondary and new wedge secondary are calculated. The effects of these two kinds secondary on thrust force ripple and system acceleration are compared. The research suggests that the new secondary structure can reduce thrust ripple and improve the stability of system acceleration.