Gas turbine power plant

• US 7,730,713 B2
• Filed: 07/23/2004
• Issued: 06/08/2010
• Est. Priority Date: 07/24/2003
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Dodo, Satoshi, Sawada, Itsurou, Hemmi, Makoto, Nakano, Susumu, Tsubouchi, Kuniyoshi, Yagi, Manabu, Inoue, Tomoaki
• Primary Examiner(s): Cuff; Michael
• Assistant Examiner(s): Nguyen; Andrew
• Application Number:
  US10/897,002
• Publication Number:
  US 20050039433A1
• Time in Patent Office: 2,146 Days
• Field of Search: 60/395.3, 60/398.3, 607/75, 608/02, 290/1, 310/52, 310/58, 310/54, 310/55, 310/90, 310/57
• US Class Current: 60/39.83
• CPC Class Codes: F01D 15/10 Adaptations for driving, or combinations with, electric generators
• CPC Class Codes: F01D 25/125 of bearings
• CPC Class Codes: F01D 25/20 using lubrication pumps
• CPC Class Codes: F02C 3/305 Increasing the power, speed, torque or efficiency of a gas turbine or the thrust of a turbojet engine by injecting or adding water, steam or other fluids F01K21/04 takes precedence
• CPC Class Codes: F02C 7/06 Arrangements of bearings bearings F16C; Lubricating of turbo machines F01D25/18; of machines or engines in general F01M
• CPC Class Codes: F02C 7/08 Heating air supply before combustion, e.g. by exhaust gases
• CPC Class Codes: F02C 7/10 by means of regenerative heat-exchangers
• CPC Class Codes: F02C 7/143 before or between the compressor stages
• CPC Class Codes: F05D 2240/53 Hydrodynamic or hydrostatic bearings
• CPC Class Codes: F05D 2260/212 by water injection

Abstract

Provided is a gas turbine power plant in which a rotor of a generator is journalled by water lubrication bearings into which a part of cooling water for cooling the generator is fed. Since the lubrication water has a viscosity lower than that of lubrication oil, it is possible to provide a gas turbine power plant with less energy loss resulting in lower power consumption for accessories, and in high power generation efficiency.

Claims

1. A gas turbine power plant comprising a compressor for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine adapted to be driven by combustion gas produced from the combustor, a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by bearings, and a cooling water circulating means for cooling the generator, wherein water lubrication bearings are arranged in the generator housing, and are used as the bearings in the generator, and cooling water is fed into the water lubrication bearings from the cooling water circulating means by way of a heat radiator, and a blower is provided for feeding outside air as sealing air between end faces of the stator winding and the water lubrication bearings in the generator housing so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings.

4. A gas turbine power plant as set forth in claim 1, wherein a spray water supply means for feeding spray water into the suction side and the discharge side of the compressor.

5. A gas turbine power plant as set forth in claim 4, wherein an impurity removal means for removing impurities from the water fed into the spray water supply means.

6. A gas turbine power plant as set forth in claim 5, wherein a change-over valve for feeding drain water from the impurity removal means into the cooling water circulating means.

7. A gas turbine power plant as set forth in claim 6, wherein the impurity removal means comprises a reverse osmotic membrane filter.

8. A gas turbine power plant as set forth in claim 7, wherein a temperature increasing means for increasing a temperature of water fed into the impurity removal means.

2. A gas turbine power plant comprising a compressor for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine adapted to be driven by combustion gas produced from the combustor, a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by bearings, and a cooling water circulating means for circulating cooling water through the generator so as to cool the generator, wherein water lubrication bearings are arranged in the generator housing and are used as the bearings in the generator, and a lubrication water supply means is provided for feeding the cooling water from the cooling water circulating means into the water lubrication bearings by way of a heat radiator, and a blower is provided for feeding outside air as sealing air between end faces of the stator winding and the water lubrication bearings in the generator housing so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings.

3. A gas turbine power plant comprising a compressor for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine driven by combustion gas produced from the combustor, a regenerative heat-exchanger for exchanging heat between exhaust gas from the gas turbine and the compressed air fed into the combustor, a generator driven by the gas turbine having, in a generator housing, a stator winding and a rotor, water lubrication bearings arranged in the generator housing, for journalling the rotor in the generator, a power converter converting an output power from the generator, into an output power having a frequency corresponding to a commercial frequency, a cooling water circulating means for feeding cooling water from a cooling water tank into the generator by way of a heat radiator, and then returning the cooling water into the cooling water tank, a lubrication water supply means for feeding the cooling water fed from the cooling water circulating means by way of the heat radiator into the water lubrication bearings, and blower for feeding outside air as sealing air between end faces of the stator winding and the water lubrication bearings in the generator housing so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings.

9. A gas turbine power plant comprising a compressor having a suction side and a discharge side, for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine adapted to be driven by combustion gas produced from the combustor, a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by bearings, and a cooling water circulating means for cooling the generator, wherein the cooling water circulating means comprises a spray water supply means including a cooling water tank, a water circulation pump for feeding water from the cooling water tank into a cooling jacket formed in the generator, by way of a heat radiator, a lubrication water supply means for feeding cooling water fed from the cooling water circulating means by way of the heat radiator, into water lubrication bearings arranged in the generator housing and serving as the bearings in the generator, a blower for feeding outside air as sealing air between end faces of the stator winding and the water lubrication bearings in the generator housing, so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings, and a spray water supply means incorporating a spray water tank for reserving water branching from the water fed into the cooling water tank, a spray water feed pump for feeding water from the spray water tank, a pipe line for returning water fed from the spray water feed pump, into the spray water tank by way of an orifice, a back pressure regulating valve provided downstream of the spray water feed pump, for setting a pressure of water therein, a pipe line for returning water into the spray water tank by way of the back pressure regulating valve, and a pipe line for feeding water by way of valves, and spray water nozzles, which are located downstream of the back pressure regulating valve, so as to inject spray water into the suction side and the discharge side of the compressor.

11. A gas turbine power plant as set forth in claim 9, wherein a control device for controlling a change-over valve for changing over drain water from a reverse osmotic membrane filter between a drain port side and the cooling water tank side, a solenoid valve provided in a drain pipe line provided to the cooling water tank, and a water feed pump in response to signals from level gages for detecting water levels in the cooling water tank and the spray water tank.

10. A gas turbine power plant comprising a compressor having a suction side and a discharge side, for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine adapted to be driven by combustion gas produced from the combustor, a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by bearings, and a cooling water circulating means for cooling the generator, wherein the cooling water circulating means comprises a spray water supply means including a cooling water tank, a water circulation pump for feeding water from the cooling water tank to a cooling jacket formed in the generator by way of a heat radiator, a lubrication water supply means for feeding cooling water fed from the cooling water circulating means by way of the heat radiator, into water lubrication bearings arranged in the generator housing and serving as the bearings in the generator, a blower for feeding outside air as sealing air between end faces of the stator winding and the water lubrication bearings in the generator housing so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings, and, a spray water supply means including a water feed pump for feeding water branching from the water fed into the cooling water tank, a spray water tank for reserving water from the water feed pump, a spray water feed pump for feeding water from the spray water tank, a pipe line for returning water fed from the spray water feed pump, into the spray water tank by way of an orifice, a back pressure regulating valve provided downstream of the spray water feed pump, for setting a pressure of water therein, a pipe line for returning water into the spray water tank by way of the back pressure regulating means, and a pipe line for feeding water by way of valves, orifices and injection nozzles, which are located downstream of the back pressure regulating valve, so as to inject spray water into the suction side and the discharge side of the compressor, and a chlorine removal filter and a reverse osmotic membrane filter which are communicated with the spray water tank is provided downstream of the water feed pump.

12. A gas turbine power plant comprising a compressor for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine adapted to be driven by combustion gas produced from the combustor, and a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by bearings, wherein water lubrication bearings arranged in the generator housing and used as the bearings for journalling the rotor of the generator and arranged in the generator housing, a cooling water circulating means for feeding cooling water by means of a water circulation pump from the cooling water tank into the generator by way of a heat radiator and returning the water into the cooling water tank, a lubrication water supply means for feeding a part of the cooling water fed through the heat radiator of the cooling water circulating means, into the water lubrication bearings by means of the water circulating pump and feeding the remainder of the cooling water into a lubrication water tank located higher than the water lubrication bearings so as to feed water from the lubrication water tank into the water lubrication bearings under a potential energy, and a blower for feeding outside air as sealing air between end faces of the stator winding and the lubrication water bearings in the generator housing so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings.

14. A gas turbine power plant as set forth in claim 12, wherein an emergency cooling water circulating means for feeding the cooling water from the cooling tank into the generator or the water lubrication bearings upon a failure of the water circulation pump.

15. A gas turbine power plant as set forth in claim 14, wherein the emergency cooling water supply means feeds the cooling water from the cooling water tank into a system upstream of the heat radiator.

13. A gas turbine power plant comprising a compressor for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine adapted to be driven by combustion gas produced from the combustor, and a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by bearings, wherein water lubrication bearings arranged in the generator housing and used as the bearings for journalling the rotor of the generator, a cooling water circulating means for feeding cooling water by means of a water circulation pump from a cooling water tank into the generator by way of a heat radiator and returning the water into the cooling water tank, and a lubrication water supply means for feeding water fed from the cooling water circulating means, through the intermediary of the heat radiator, into the water lubrication bearings by way of an accumulator, and a blower for feeding outside air as sealing air between end faces of the stator winding and the lubrication water bearings in the generator housing so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings.

16. A method of operating a gas turbine power plant comprising a compressor for compressing air, a combustor for mixing the compressed air with fuel so as to burn the fuel, a gas turbine driven by combustion gas produced from the combustor, a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by water lubrication bearings, a cooling water circulating means for cooling the generator so that cooling water from a cooling water tank is fed by a water circulation pump into the generator by way of a heat radiator, and is then returned into the cooling water tank, and a lubrication water supply means for feeding a part of the cooling water fed from the cooling water circulating means by way of the heat radiator, into the water lubrication bearings through the water supply of the water circulation pump, and for feeding the remainder of the cooling water into a lubrication water tank located at a level higher than the water lubrication bearings in order to feed water into the water lubrication bearings from the lubrication water tank with the use of a potential energy, wherein

the lubrication water is fed from both or one of the water circulation pump and the lubrication water tank during normal operation, but the lubrication water is fed from the lubrication water tank when the water circulation pump comes to a stop upon a failure thereof, and a blower is provided for feeding sealing air between end faces of the stator winding and the water lubrication bearings in the generator housing.

17. A gas turbine power plant comprising a compressor for compressing air, a combustor for mixing compressed air with fuel so as to burn the fuel, a gas turbine driven by combustion gas produced from the combustor, a generator having, in a generator housing, a stator winding and a rotor driven by the gas turbine and journalled by bearings, and a cooling water circulating means for cooling the generator, wherein water lubrication bearings are arranged in the generator housing and used as the bearings in the generator, cooling water from the cooling water circulating means is fed into the water lubrication bearings, and a blower for feeding outside air as sealing air between end faces of the stator winding and the water lubrication bearings so as to allow the sealing air to define a seal surface against water scattering from the water lubrication bearings.