Turbine generator starting method and turbine generation system

• US 6,847,129 B2
• Filed: 12/06/2002
• Issued: 01/25/2005
• Est. Priority Date: 12/07/2001
• Status: Active Grant

• Current Assignee: Ebara Corporation
• Original Assignee: Ebara Corporation
• Inventors: McKelvey, Terence, Furuya, Tai
• Primary Examiner(s): Ponomarenko, Nicholas
• Assistant Examiner(s): Gonzalez, Julio C.
• Application Number:
  US10/380,468
• Publication Number:
  US 20040080164A1
• Time in Patent Office: 781 Days
• Field of Search: 290/52, 290/1.A, 290/46, 322/36, 417/319, 417/53, 363/96, 363/95, 318/140, 318/145, 318/147
• US Class Current: 290/52
• CPC Class Codes: F02C 7/26 Starting; Ignition
• CPC Class Codes: F02C 7/268 Starting drives for the rotor , acting directly on the rotor of the gas turbine to be started
• CPC Class Codes: H02P 9/04 Control effected upon non-electric prime mover and dependent upon electric output value of the generator
• CPC Class Codes: H02P 9/08 Control of generator circuit during starting or stopping of driving means, e.g. for initiating excitation
• CPC Class Codes: Y02E 20/14 Combined heat and power generation [CHP]

Abstract

An object of the present invention is to provide a turbine generation system in which a starting inverter circuit for starting a turbine generator is additionally employed so that the system comprises a high-power generation inverter and the starting inverter with low-power, thereby utilizing the inverter for multiple purposes. To this end, the present invention comprises an inverter control circuit for deactivating a pulse-width modulation inverter for generation connected to a turbine generator, and first switching means for connecting an internal power supply to the turbine generator, wherein the inverter control circuit controls the starting inverter to supply the turbine generator with power to drive it up to a purge speed and accelerate it to a predetermined starting speed.

Claims

1. A method of starting a turbine generator using an internal power supply, comprising the steps of:

deactivating a pulse-width-modulation inverter for generation connected to the turbine generator;

supplying DC power to a pulse-width-modulation inverter for starting from the internal power supply through a DC matching circuit;

closing first switching means to connect the starting inverter to the turbine generator;

driving the turbine generator up to a purge speed and supplying power from the starting inverter to the turbine generator for acceleration up to a predetermined starting speed;

driving gates of the starting inverter in response to a pulse-width-modulated signal received from an inverter control circuit;

deactivating the starting inverter after the speed of the turbine generator reaches a predetermined starting speed, and opening the first switching means to isolate the starting inverter from the turbine generator; and

activating the generation inverter.

2. A method of starting a turbine generator using an external commercial power supply, comprising the steps of:

deactivating a pulse-width-modulation inverter for generation connected to the turbine generator;

closing second switching means to connect the commercial power supply to a rectifier for starting, and closing third switching means to connect the rectified power from the commercial power supply to a DC bus;

supplying a pulse-width-modulation inverter for starting with the rectified power from the commercial power supply through a DC matching circuit;

closing first switching means to connect the starting inverter to the turbine generator;

driving the turbine generator up to a purge speed and supplying power from the starting inverter to the turbine generator for acceleration up to a predetermined starting speed;

driving gates of the starting inverter in response to a pulse-width-modulated signal received from an inverter control circuit;

deactivating the starting inverter after the speed of the turbine generator reaches a predetermined starting speed, opening the first switching means to isolate the starting inverter from the turbine generator, opening the third switching means to isolate the rectified power from the commercial power supply from the DC bus and opening the second switching means to disconnect the starting rectifier from the commercial power supply; and

activating the generation inverter (ON state).

3. A turbine generation system in which a turbine generator is started by an internal power supply, comprising:

a pulse-width-modulation inverter for starting supplied with DC power from the internal power supply through a DC matching circuit;

first switching means for connecting the starting inverter to the turbine generator; and

an inverter control circuit for controlling to deactivate an inverter for generation connected to the turbine generator, drive the turbine generator up to a purge speed, supply the turbine generator with power from the starting inverter for acceleration up to a predetermined starting speed, deactivate the starting inverter (OFF state) after the speed of the turbine generator reaches the predetermined starting speed, and open the first switching means to isolate the starting inverter from the turbine generator, and activate the generation inverter.

6. A turbine generation systems according to anyone of claims 3-5 wherein the inverter control circuit further controls to switch the opened first switching means to connect the output of the starting inverter to a pump driven motor to drive a circulating pump of a boiler for recovering waste heat of the turbine generator therethrough.

4. A turbine generation system in which a turbine generator is started by an external commercial power supply, comprising:

second switching means for connecting the commercial power supply to a rectifier for starting;

third switching means for connecting the rectified power from the commercial power supply to a DC bus;

fourth switching means for supplying the rectified power from the commercial power supply to a pulse-width-modulation inverter for starting through a DC matching circuit;

first switching means for connecting the starting inverter to the turbine generator; and

an inverter control circuit for controlling to deactivate a pulse-width-modulation inverter for generation connected to the turbine generator, drive the turbine generator up to a purge speed, supply the turbine generator with power from the starting inverter for acceleration up to a predetermined starting speed, deactivate the starting inverter after the speed of the turbine generator reaches the predetermined starting speed, open the first switching means to isolate the starting inverter from the turbine generator, open the third switching means to isolate the rectified power from the commercial power supply from the DC bus, open the second switching means to disconnect the starting rectifier from the commercial power supply, and activate the generation inverter.

5. A turbine generation system for supplying AC power, having a turbine generator, a rectifier, a DC matching circuit and a pulse-width-modulation inverter for generation connected in series, comprising:

a pulse-width-modulation inverter for starting connected to an output of the DC matching circuit;

first switching means for connecting the starting inverter to the turbine generator;

second switching means for connecting the generation inverter to a commercial power supply;

third switching means for connecting the commercial power supply to an input of the rectifier through the second switching means; and

an inverter control circuit for controlling to drive the turbine generator up to a purge speed while maintaining the generation inverter deactivated, supply the turbine generator with AC power from the starting inverter for acceleration up to a predetermined starting speed, open the first switching means to disconnect the output of the starting inverter from the turbine generator after the speed of the turbine generator reaches a predetermined starting speed, open the third switching means to disconnect the commercial power supply from the rectifier, and activate the generation inverter to link the turbine generation system to the commercial power supply.

7. A turbine generation system for supplying AC power, having a turbine generator, a rectifier, a DC matching circuit and a pulse-width-modulation inverter for generation connected in series, comprising:

a pulse-width-modulation inverter for starting connected to an output of the DC matching circuit;

first switching means disposed between the starting inverter and first stator windings of the turbine generator;

second switching means disposed between the generation inverter and the commercial power supply;

third switching means disposed between an input of the rectifier and the commercial power supply;

fifth switching means disposed between an output of the generation inverter and second stator windings of the turbine generator;

fourth switching means disposed between the rectifier and the first and second stator windings of the turbine generator; and

an inverter control circuit for controlling to close the first switching means, the third switching means and the fifth switching means, activate the starting inverter and the generation inverter, drive the turbine generator up to a purge speed, supply the first and second stator windings of the turbine generator with AC power from the starting inverter and the generation inverter, respectively, for acceleration up to a predetermined starting speed, open the first switching means, the third switching means and the fifth switching means to disconnect the outputs of the starting inverter and the generation inverter from the first and second stator windings of the turbine generator, respectively after the speed of the turbine generator reaches a predetermined starting speed, and close the second switching means and the fourth switching means to link the turbine generation system to the commercial power supply.

8. A turbine generation system according to claim 7 wherein the inverter control circuit further controls to close the first switching means to supply the first stator windings with AC power for applying a reverse torque to a rotor at the time a linkage to the commercial power supply is released, and subsequently open the second switching means.

9. A turbine generation system according to claim 7 or 8 wherein the inverter control circuit further controls to switch the opened first switching means to connect the output of the starting inverter to a pump driven motor to drive a circulating pump of a boiler for recovering waste heat of the turbine generator therethrough.