Reluctance motor power circuit

{
  "publication_number": "US3560817A",
  "country": "US",
  "kind": "A",
  "title": "Reluctance motor power circuit",
  "abstract": "Conventional SCRs and diodes are used to apply DC electric power from a storage battery to a winding of a reluctance-type motor. The circuit provides full and partial motoring and regenerative braking, freewheels the winding current at low speeds to improve motor torque, and returns winding current to the storage battery at the end of the motoring cycle to improve efficiency. Electrically powered automotive vehicles use the circuit to great advantage and the circuit also can be used in stationary industrial applications.",
  "claims": [
    "1. In a reluctance motor having a motor winding that has a varying inductance during motor operation, a power circuit for applying electrical power from a DC source of electrical energy having a positive terminal and a negative terminal to said motor winding comprising: a primary switching device connecting the positive terminal of said source of electrical energy to the primary terminal of said motor winding and a secondary switching device connecting the secondary terminal of the motor winding to the negative terminal of said source of electrical energy; a primary commutating means connected in parallel with said primary switching device and a secondary commutating means connected in parallel with said secondary switching device, each of said commutating means including a commutating capacitor in series with a commutating switching device; and a primary rectifying device having its anode connected to the negative terminal of said source of electrical energy and its cathode connected to the primary terminal of the motor winding, and a secondary rectifying device having its anode connected to the secondary terminal of the motor winding and its cathode connected to the positive terminal of said source of electrical energy.",
    "2. The reluctance motor of claim 1 in which each commutating means includes means for reversing the charge on its commutating capacitor.",
    "3. The reluctance motor of claim 2 in which each charge-reversing means includes an inductor in series with a switching device, each inductor and switching device being connected in parallel with its commutating capacitor.",
    "4. The reluctance motor of claim 3 in which the switching devices are thyristors and the rectifying devices are diodes.",
    "5. The reluctance motor of claim 4 comprising a plurality of motor windings, primary and secondary switching devices for each motor winding, primary and secondary rectifying devices for each winding, and a single primary commutating means and a single secondary commutating means, said primary commutating means commutating each of the primary switching devices and said secondary commutating means commutating each of the secondary switching devices.",
    "6. The reluctance motor of claim 5 in which the primary commutating capacitor and the primary commutating switching device are connected in parallel with the primary switching device of one phase.",
    "7. The reluctance motor of claim 6 in which a primary commutating switching device for the primary switching device of the second winding is connected in series with the primary commutating capacitor of the first winding.",
    "8. The reluctance motor of claim 1 comprising a plurality of motor windings, primary and secondary switching devices for each motor winding, primary and secondary rectifying devices for each winding, and a single primary commutating means and a single secondary commutating means, said primary commutating means commutating each of the primary switching devices and said secondary commutating means commutating each of the secondary switching devices.",
    "9. The reluctance moTor of claim 1 in which the switching devices are thyristors and the rectifying devices are diodes.",
    "10. A process for producing current in the winding of a variable reluctance motor comprising: coupling a source of electrical energy across the winding until current in the winding reaches a predetermined value; freewheeling the current in the winding under the induced voltage generated by the self-inductance in the winding until the current reaches a predetermined value; reinforcing the current by coupling again the source of electrical energy across the winding; decoupling again the source of electrical energy from the winding when current in the winding reaches a predetermined value; and returning current from the winding under the induced voltage generated by the self-inductance in the winding to the source of electrical energy.",
    "11. The process of claim 10 comprising freewheeling the current in the winding under the induced voltage generated by the self-inductance in the winding after the current has been reinforced.",
    "12. The process of claim 11 comprising commutating a solid-state switching device to perform said decoupling steps by storing an electrical charge from said source of electrical energy on a capacitor coupled in parallel with said switching device, reversing said stored charge across said capacitor, coupling said charge across said switching device at the predetermined time, and discharging said capacitor through said motor winding to increase the current in the motor winding."
  ],
  "cpc": [
    "H02K 29/06",
    "B60L 50/14",
    "H02K 19/103",
    "Y02T 10/64",
    "Y02T 10/70",
    "Y02T 10/7072"
  ],
  "assignees": [
    "FORD MOTOR CO"
  ],
  "filing_date": "1969-01-31",
  "publication_date": "1971-02-02",
  "grant_date": "1971-02-02",
  "priority_date": "1969-01-31",
  "application_number": "US-3560817D-A",
  "family_id": "25165448",
  "citations": [
    "US3207974A",
    "US3299336A",
    "US3308371A",
    "US3321685A",
    "US3437854A",
    "US3444447A",
    "US3466519A"
  ]
}