IMPROVEMENTS IN ELECTRICAL MACHINES

摘要

An alternating current electrical machine construction in which a primary winding is modified to create transient electromagnetic conditions for example by having at least two distinct values of pole pitch. In a linear induction motor a first pole-pitch portion (STAL) is followed by a second portion (STAA) of shorter pole-pitch. When an inductively coupled solid rotor passes from first to second rotor currents "memorised" from the first, propulsion, section cause current in the second, recovery section. This current can be of unity or leading power factor. Appropriate winding design permits the operation of the machine using an inverter (LCIA) without making provision for reactive power supply. Part of the machine winding, the recovery section, functions as an asynchronous condenser (ASCA) to cope with the reactive power components In a cylindrical machine the winding modification can provide transient creating pole or part-pole windings controlling the quadrature flux component.