A combined system of propulsion and guidance by linear synchronous motors

Abstract

I b a r a k i , J a p a n ABSTFACT This paper describes the principle, various chara c t e r i s t i c s and t e s t r e s u l t s of a canbined system of ropulsion and guidance by linear synchronous motors CSPG) s u i t a b l e f o r h i g h s p e e d l e v i t a t e d trains. The CSPG proposed here i s a very econanic system without usual guidance coils on the track. Instantaneous prcpulsion and guidance forces are obtained by canputer simulation,and i t i s found how t h e train displacement, phase angle of the armature current and train speed a f f e c t t h e c h a r a c t e r i s t i c s of a CSPG. It i s a l s o f o u n d t h a t t h e c m p u t e d r e s u l t s a g r e e w i t h t h e t e s t r e s u l t s of t h e r o t a t i n g e x p e r i m e n t a l f a c i l i t y . P IITTROWCTION Approaches f o r d e v e l o p i n g f u t u r e t r a i n s r u n n i n g l e v i t a t e d a t s p e e d s i n excess of 300 km/h a e s e r iously b 4 n g considered in s e v e r a l c c u n t r i e s . (17The system applying magnetic repulsive suspension and linear synchronous motor(L3) propulsion with on board superconducting magnets i s one advantageous system for high spee evltated trains, and i t has the folloKing f e a t u r e s . f 2 j ' 1) There can be l a r g e c l e a r a n c e between t h e t r a i n a n d 2) C o l l e c t o r i s not necessary. 3) I t has good propulsion characteristics. However, t h e t r a c k f a c i l i t i e s must be reduced since t h e c o i l s a r e e n e r g i z e d on the track. Null flux guidan e i s s u i t a b l e as a means of guidance f o r t h i s systemr3) In null flux guidance, a guidance force i s produced f r m t h e i n t e r a c t i o n of induced c u r r e n t s i n t h e t r a c k c o n d u c t o r s k i t h t h e f i e l d f r a n the superconducting magnets when t h e t r a i n d i s p l a c e s l a t e r a l l y . t h e t r a c k . The CSPG proposed h e~-e (~) i s a new system i n which a null flux guidance force and a linear synchronous m o t o r (L%> propulsion force are produced on t h e same armature coils. Since usual guidance coils are not n e c e s s a r y i n a CSPG, t h e t r a c k f a c i l i t i e s can be reduced by l e s s t h a n 2/j. Therefore, a CSPG serves t o r e a l i z e an economic high sF?ed levitated train. The superconducting magnetic flux in a CSPG has a three-dimensional distribution and higher harmonic components than those in an ordinary rotating machine. Electranagnetic forces produced on t h e train are pulsating three-dimentional forces,i.e. propulsion, guida c e a n d v e r t i c a l f o r c e ? . S i n c e t h e c l e a r a n c e between J. F u j i e T . I wahaua Railway Technical Research Institute J N R Tokyo, Japan t h e train magnets and the track armature coils i s cons i d e r a b l e ( a b m t 0.25 m ) , f i e l d m a g n e t i c f l u x d e n s i t y a t the armature coil i s n o t much l a r g e r t h a n t h a t in an ordinary rotating machine. A s u i t a b l e c o i l c o n f i g ur a t i o n i s determined considering ...