Reluctance motor with electronically controlled stator windings

Claim 1

In an electric motor having a stator with multiple sequentially energizable phase windings and a rotor magnetized to seek a minimum reluctance position within a progressively moving electromagnetic field produced by said phase windings, first controlled switching means in series relative to a D.C. power supply with each phase winding, and means to control said first switching means to produce said progressively moving electromagnetic field, the improvement wherein (a) a charge storage capacitor is provided for each such phase winding, with one terminal of said capacitor connected by a low impedance path to said supply, and the other terminal having first and second connections establishing alternative low impedance paths to opposite ends of the winding, the first such connection being established by first diode means to that end of the winding connection to the first switching means, the first diode means being oriented to permit low impedance passage to said capactior of forward current continuing in said winding after turn-off of the switching means, and the second such connection being established by second controlled switching means, (b) means are provided to turn on said second switching means substantially simultaneously with said first switching means to provide low impedance passage of current from said capacitor to said end of the winding remote from the first switching means, and (c) second diode means are provided between the supply and said remote end of the winding such as to present a low impedance path for forward current from the supply, but a high impedance to reverse current.