Normal zone detectors for a large number of inductively coupled coils

Abstract

P.O.iW. >>Il.t-kJ» AtjtfjgjIn arerr to !»sstrct i «t ci tnOuctivv-ly coupled luperconajcti^i; <-.a|r>e«s. <i» i» neceisary to locate and measure normal rOTW »;-;s,)ge» that are small compared with the mutual ana vell«raJuced toltages. The method described in thitpapn usrt two telsoi toltage measurement! to locate And measure one or more r.otmai tone) in any number ol CVKV-JM ceils. One set ol voltages is the outputs ol bridges tut balance out the sell-induced voltages. The other set o! voltages ean be the voltages across the coil* although alternatives are possible. The two set* oi equations lorin a single combined set ol equations.Each normal zone location or combination ol normal zones has a set oi these combined equatisns associated with it. It is demonstrated that the normal zone can be located and the correct set chcsen, allowing determination ol the size oi the normal zone. Only a tew operations take place in a working detector: multiplication ol a constant, addition, and simple decision-making. In many cases the detector lor each coil, although weakly linked to the other detectors, can be considered to be independent.