STARTING SYSTEM FOR POWER PLANTS

• US 3,809,914 A
• Filed: 07/13/1972
• Issued: 05/07/1974
• Est. Priority Date: 07/13/1972
• Status: Expired due to Term

• Current Assignee: Bernard S. Strait Jr, Henry L. Smith, Lee A. Kilgore, Robert E.G. Ratcliffe
• Original Assignee: Bernard S. Strait Jr, Henry L. Smith, Lee A. Kilgore, Robert E.G. Ratcliffe
• Inventors: Kilgore, Lee A., Strait, Bernard S. Jr., Ratcliffe, Robert E. G., Smith, Henry L.
• Primary Examiner(s): Simmons, G. R.
• Application Number:
  US05/271,427
• Time in Patent Office: 663 Days
• Field of Search: 290/36,38,46,11,16,21,52 318/227,230
• US Class Current: 290/38.00R
• CPC Class Codes: H02P 2101/30 for aircraft
• CPC Class Codes: H02P 9/08 Control of generator circuit during starting or stopping of driving means, e.g. for initiating excitation

Abstract

A starting system for power plants having a prime mover which is not self-starting, such as a gas turbine, or for other synchronous machines which are not self-starting. The generator or other synchronous machine has an exciter which is designed to operate as a wound rotor induction motor for starting and as a normal exciter thereafter.

Claims

1. In combination, a synchronous dynamoelectric machine having a rotor member carrying a field winding, a second dynamoelectric machine having a stator member carrying a stator winding and a rotor member carrying a rotor winding, said rotor members being mechanically connected together for rotation as a unit, means for energizing the stator winding of said second machine with alternating current, means for connecting external resistance means to the rotor winding of the second machine to enable operation of the second machine as a variable speed motor when its stator winding is energized with alternating current, means for alternatively energizing the stator winding of the second machine with direct current for operation of the second machine as an alternating current generator, means for rectifying the output of the rotor winding of the second machine when it is being operated as a generator, mEans for applying said rectified output to the field winding of said synchronous machine, and a prime mover mechanically connected in driving relation to said rotor members.

2. The combination of claim 1 in which the prime mover is a gas turbine.

3. The combination of claim 1 wherein:

said means for rectifying the output of the rotor winding of the second machine and said means for applying said rectified output to the field winding of said synchronous machine comprise elements that are located outside of said rotatable unit that includes said rotors and are connected to said rotor windings through rotatable electrical connections.

4. The combination of claim 1 wherein:

said means for rectifying the output of the rotor winding of the second machine and said means for applying said rectified output to the field winding of said synchronous machine comprise elements that are located within said rotatable unit that includes said rotors.

5. The combination of claim 4 wherein:

said rotor of said second machine carries a winding of first and second electrically separate portions, said first portion is connected to said means for rectifying the output of the rotor winding, and said means for connecting external resistance means to the rotor winding is connected to said second portion of said winding.