Frequency switching systems for portable power modules

• US 6,644,247 B2
• Filed: 10/23/2001
• Issued: 11/11/2003
• Est. Priority Date: 08/08/2001
• Status: Expired due to Fees

• Current Assignee: Aggreko LLC (Aggreko Ltd.)
• Original Assignee: General Electric Company
• Inventors: Campion, Edmund
• Primary Examiner(s): Kamen, Noah P.
• Application Number:
  US10/002,648
• Publication Number:
  US 20030030281A1
• Time in Patent Office: 749 Days
• Field of Search: 123/2, 290/40.R, 290/51, 294/011
• US Class Current: 123/2
• 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: Y10T 29/49716 Converting

Abstract

Frequency switching systems for changing the frequency of electrical power provided by portable power modules trailerable over public roads and capable of providing at least approximately one megawatt of electrical power. In one embodiment, the portable power module includes a shipping container housing a gaseous fuel motor drivably connected to an electrical generator. The frequency switching system includes a turbocharger operatively connected to the motor and having interchangeable components that allow selecting a first or second turbocharger configuration. The selected turbocharger configuration determines the RPM of the motor, which in turn determines the frequency of the electrical power produced by the generator. In one embodiment, the first turbocharger configuration results in a motor speed of 1500 RPM and a frequency of 50 Hz, and the second turbocharger configuration results in a motor speed of 1800 RPM and a frequency of 60 Hz.

Claims

1. A method for changing the frequency of electrical power provided by a portable power module capable of providing at least approximately one megawatt of electrical power, the portable power module being trailerable over public roads and including a container and a gaseous fuel motor drivably connected to an electrical generator, the motor including a combustion chamber and a coolant jacket positioned adjacent to the combustion chamber to circulate liquid coolant, the portable power module further including a radiator connected in flow communication with the coolant jacket and an exhaust gas silencer connected in flow communication with the combustion chamber via an exhaust gas duct, the portable power module further including a turbocharger having a driving portion drivably coupled to a driven portion, the driven portion being connected in upstream flow communication with the combustion chamber and the driving portion being connected in downstream flow communication with the combustion chamber between the combustion chamber and the exhaust gas silencer, the method for changing the frequency of electrical power comprising:

determining a first frequency of electrical power provided by the portable power module in a normal operating configuration, wherein the motor, the generator, the radiator and the exhaust gas silencer are positioned inside the container when the portable power module is in a normal operating configuration;

when the first frequency is 50 Hz, disconnecting the driving portion of the turbocharger from the motor, the driving portion being a first driving portion capable of causing the motor to operate at a first speed,

wherein disconnecting the first driving portion from the motor includes;

disconnecting the first driving portion from the exhaust gas duct;

disconnecting the first driving portion from a turbocharger bypass;

disconnecting the first driving portion from an exhaust gas manifold; and

disconnecting the first driving portion from the driven portion;

connecting a second driving portion to the motor, the second driving portion being capable of causing the motor to operate at a second speed higher than the first speed, wherein connecting the second driving portion to the motor includes;

connecting the second driving portion to the driven portion;

connecting the second driving portion to the exhaust gas manifold;

connecting the second driving portion to the turbocharger bypass; and

connecting the second driving portion to the exhaust gas duct; and

operating the motor at the second speed;

when the first frequency is 60 Hz, disconnecting the driving portion of the turbocharger from the motor, the driving portion being the second driving portion capable of causing the motor to operate at the second speed, wherein disconnecting the second driving portion from the motor includes;

disconnecting the second driving portion from the exhaust gas duct;

disconnecting the second driving portion from the turbocharger bypass;

disconnecting the second driving portion from the exhaust gas manifold; and

disconnecting the second driving portion from the driven portion;

connecting first driving portion to the motor, the first driving portion being capable of causing the motor to operate at the first speed lower than the second speed, wherein connecting the first driving portion to the motor includes;

connecting the first driving portion to the driven portion;

connecting the first driving portion to the exhaust gas manifold;

connecting the first driving portion to the turbocharger bypass; and

connecting the first driving portion to the exhaust gas duct; and

operating the motor at the first speed.

2. The method of claim 1 wherein the first speed is 1500 RPM and the second speed is 1800 RPM.

3. The method of claim 1 wherein the portable power module further includes a voltage switch electrically connected to the generator to control the electrical power provided by the generator, the voltage switch having a 400 Volt position and a 480 Volt position, wherein the method for changing the frequency of electrical power further comprises:

when the first frequency is 50 Hz, changing the position of the voltage switch from the 400 Volt position to the 480 Volt position to set the voltage of electrical power provided by the generator to approximately 480 Volts; and

when the first frequency is 60 Hz, changing the position of the voltage switch from the 480 Volt position to the 400 Volt position to set the voltage of electrical power provided by the generator to approximately 400 Volts.

4. The method of claim 1 wherein the portable power module further includes a circuit breaker electrically connected to the generator to control the electrical power provided by the generator, the circuit breaker having a 1600 Amp setting and a 1900 Amp setting, wherein the method for changing the frequency of electrical power further comprises:

when the first frequency is 50 Hz, setting the circuit breaker to the 1600 Amp setting to limit the current provided by the generator to approximately 1600 Amps; and

when the first frequency is 60 Hz, setting the circuit breaker to the 1900 Amp setting to limit the current provided by the generator to approximately 1900 Amps.

5. The method of claim 1 wherein the portable power module further includes a voltage switch and a circuit breaker electrically connected to the generator to control the electrical power provided by the generator, the voltage switch having a 400 Volt position and a 480 Volt position, the circuit breaker having a 1600 Amp setting and a 1900 Amp setting, wherein the method for changing the frequency of electrical power further comprises:

when the first frequency is 50 Hz, changing the position of the voltage switch from the 400 Volt position to the 480 Volt position to set the voltage of electrical power provided by the generator to approximately 480 Volts; and

setting the circuit breaker at the 1600 Amp setting to limit the current to approximately 1600 Amps; and

when the first frequency is 60 Hz, changing the position of the voltage switch from the 480 Volt position to the 400 Volt position to set the voltage of electrical power provided by the generator to approximately 400 Volts; and

setting the circuit breaker at the 1900 Amp setting to limit the current to approximately 1900 Amps.

6. A method for changing the frequency of electrical power provided by a portable power module, the portable power module including a motor drivably connected to an electrical generator for providing electrical power at a first frequency when driven by the motor at a first motor speed, the motor including a combustion chamber configured to receive an air/fuel mixture through an intake manifold and to discharge exhaust gases through an exhaust gas manifold, the portable power module further including a turbocharger having a first driving portion drivably connected to a driven portion, the driven portion configured to pressurize the air/fuel mixture received by the combustion chamber, the first driving portion configured to drive the driven portion by interaction with the exhaust gases discharging from the combustion chamber, the method for changing the frequency of electrical power comprising:

changing the first motor speed to a second motor speed by replacing the first driving portion of the turbocharger with a second driving portion, the first driving portion being replaced with the second driving portion by a method including the steps of;

disconnecting the first driving portion of the turbocharger from the driven portion, and

drivably connecting the second driving portion to the driven portion.

7. The method of claim 6 wherein changing the first motor speed to a second motor speed includes one of:

changing the first motor speed of 1500 RPM to a second motor speed of 1800 RPM to correspondingly change the frequency of electrical power from 50 Hz to 60 Hz; and

changing the first motor speed of 1800 RPM to a second motor speed of 1500 RPM to correspondingly change the frequency of electrical power from 60 Hz to 50 Hz.

8. The method of claim 6 wherein the portable power module further includes one or more throttle valves for controlling the amount of the air/fuel mixture received by the combustion chamber, wherein the generator provides electrical power at the first frequency when driven by the motor at the first motor speed when the one or more throttle valves are in a first position, and wherein the method for changing the frequency of electrical power further comprises:

maintaining the motor speed and the generator speed in a one-to-one correspondence; and

maintaining the one or more throttle valves in the first position.

9. The method of claim 6 wherein the first driving portion is replaced with the second driving portion by the method further including the steps of:

disconnecting the first driving portion from an exhaust gas duct;

disconnecting the first driving portion from a turbocharger bypass;

disconnecting the first driving portion from the exhaust gas manifold;

connecting the second driving portion to the exhaust gas manifold;

connecting the second driving portion to the turbocharger bypass; and

connecting the second driving portion to the exhaust gas duct.

10. The method of claim 6 wherein the portable power module further includes a voltage switch and a circuit breaker electrically connected to the generator to control the electrical power provided by the generator, the voltage switch having a 400 Volt position and a 480 Volt position, the circuit breaker having a 1600 Amp setting and a 1900 Amp setting, wherein the method for changing the frequency of electrical power further comprises at least one of:

changing the position of the voltage switch from the 400 Volt position to the 480 Volt position to set the voltage of electrical power provided by the generator to approximately 480 Volts;

changing the setting of the voltage switch from the 480 Volt setting to the 400 Volt setting to set the voltage of electrical power provided by the generator to approximately 400 Volts;

setting the circuit breaker at the 1600 Amp setting to limit the current to approximately 1600 Amps; and

setting the circuit breaker at the 1900 Amp setting to limit the current to approximately 1900 Amps.

11. A method for changing the frequency of electrical power provided by a portable power module, the portable power module including a motor drivably connected to an electrical generator to operate in one-to-one correspondence, the motor including a combustion chamber configured to receive an air/fuel mixture through a turbocharger and one or more throttle valves, the position of the one or more throttle valves controlling the amount of the air/fuel mixture received by the combustion chamber, the generator providing electrical power at a first frequency when operated at a first RPM and a second frequency when operated at a second RPM, the method for changing the frequency of electrical power comprising:

maintaining the motor speed and the generator speed in one-to-one correspondence;

maintaining the one or more throttle valves in a fixed position; and

changing the first RPM to the second RPM by reconfiguring the turbocharger.

12. The method of claim 11 wherein the turbocharger has a first driving portion drivably connected to a driven portion, the driven portion configured to pressurize the air/fuel mixture received by the combustion chamber, the first driving portion configured to drive the driven portion by interaction with exhaust gases discharging from the combustion chamber, and wherein reconfiguring the turbocharger includes replacing the first driving portion of the turbocharger with a second driving portion, the first driving portion being replaced with the second driving portion by a method including the steps of:

disconnecting the first driving portion of the turbocharger from the driven portion, and

drivably connecting the second driving portion to the driven portion.

13. The method of claim 11 wherein changing the first RPM to the second RPM includes one of:

changing 1500 RPM to 1800 RPM to correspondingly change the frequency of electrical power from 50 Hz to 60 Hz; and

changing 1800 RPM to 1500 RPM to correspondingly change the frequency of electrical power from 60 Hz to 50 Hz.

14. A portable power module trailerable over public roads and capable of providing at least approximately one megawatt of electrical power in a normal operating configuration, the portable power module comprising:

a container defining a first interior portion and a second interior portion, the container including a first side portion spaced apart from an opposing second side portion and a bottom portion spaced apart from an opposing top portion, the bottom and top portions being at least partially interposed between the first and second side portions;

a gaseous fuel motor positioned within the first interior portion, the motor having a combustion air intake in flow communication with a combustion chamber and a coolant jacket positioned adjacent to the combustion chamber to circulate liquid coolant;

an electrical generator positioned within the first interior portion and drivably connected to the motor to produce at least one megawatt of electrical power at a first frequency when driven by the motor at a first speed and at a second frequency when driven by the motor at a second speed, the generator including a generator air intake configured to receive cooling air;

a radiator positioned within the second interior portion in flow communication with the coolant jacket, the radiator configured to receive the liquid coolant from the coolant jacket and return the coolant to the coolant jacket;

an exhaust gas silencer positioned within the container and having an exhaust gas outlet positioned on the top portion of the container, the exhaust gas silencer connected in flow communication with the combustion chamber and configured to receive exhaust gases from the combustion chamber and vertically discharge the exhaust gases through the exhaust gas outlet; and

a frequency switching system to change from the first frequency to the second frequency and vice versa, the frequency switching system including a turbocharger optionally configurable in a first configuration or a second configuration, the first configuration including a first driving portion drivably coupled to a driven portion, the second configuration including a second driving portion interchangeable with the first driving portion drivably coupled to the driven portion, the driven portion being connected in upstream flow communication with the combustion chamber, the first and second driving portions being connectable in downstream flow communication with the combustion chamber between the combustion chamber and the exhaust gas silencer.

15. The portable power module of claim 14 wherein the generator provides electrical power to an electrical system onboard the portable power module, and wherein the frequency switching system further includes:

a voltage switch electrically connected to the generator for controlling the voltage provided by the generator;

a circuit breaker electrically connected to the generator for controlling the amperage provided by the generator; and

a variable speed frequency drive for adapting the electrical system onboard the portable power module to the frequency of electrical power provided by the generator.

16. The portable power module of claim 14 wherein the frequency switching system further includes:

a voltage switch electrically connected to the generator, the voltage switch having a 400 Volt position and a 480 Volt position; and

a circuit breaker electrically connected to the generator, the circuit breaker having a 1600 Amp setting and a 1900 Amp setting, wherein the portable power module provides approximately 400 Volts at a frequency of 50 Hz when the voltage switch is positioned to the 400 Volt position and the circuit breaker is set to the 1900 Amp setting, and wherein the portable power module provides approximately 480 Volts at a frequency of approximately 60 Hz when the voltage switch is positioned to the 480 Volt position and the circuit breaker is set to the 1600 Amp setting.

17. The portable power module of claim 14 wherein the container has an overall length dimension of about 40 feet or less, an overall width dimension of about 8 feet or less, and an overall height dimension of about 8.5 feet or less.

18. The portable power module of claim 14 wherein the combustion chamber is configured to combust a fuel mixture comprising natural gas.

19. The portable power module of claim 14 wherein the generator produces at least approximately one megawatt of electrical power at 50 Hz when the turbocharger is in the first configuration, and wherein the generator produces at least approximately one megawatt of electrical power at 60 Hz when the turbocharger is in the second configuration.

20. The portable power module of claim 14 wherein the generator operates at approximately 1500 RPM and produces at least approximately one megawatt of electrical power at 50 Hz when the turbocharger is in the first configuration, and wherein the generator operates at approximately 1800 RPM and produces at least approximately one megawatt of electrical power at 60 Hz when the turbocharger is in the second configuration.

21. The portable power module of claim 14 further comprising a trailer supporting the container and its contents, the trailer having a tandem axle rear wheel-set and a forward coupling, the coupling being releasably attachable to a transport vehicle for movement of the portable power module.

22. The portable power module of claim 14 further comprising:

a first air circuit including a first air inlet positioned on the container adjacent to the first interior portion to provide an ambient first air portion to the first interior portion at least substantially to the exclusion of the second interior portion; and

a second air circuit including a second air inlet positioned on the container adjacent to the second interior portion to provide an ambient second air portion to the second interior portion at least substantially to the exclusion of the first interior portion.

23. The portable power module of claim 22 wherein the first air inlet is positioned on one of the first or second side portions, wherein the second air inlet is positioned on one of the first or second side portions, and wherein the portable power module further comprises:

a first air outlet positioned on the top portion of the container to vertically discharge at least a fraction of the first air portion; and

a second air outlet positioned on the top portion of the container to vertically discharge at least a fraction of the second air portion.

24. The portable power module of claim 22 wherein the first air portion provides ambient air to the combustion air intake and the generator air intake, and wherein the second air portion provides ambient air proximate to the radiator to cool the coolant received from the coolant jacket.

25. The portable power module of claim 22 wherein the first air inlet is positioned on one of the first or second side portions, wherein the second air inlet is positioned on one of the first or second side portions, and wherein the portable power module further comprises:

a first air outlet positioned on the top portion of the container to vertically discharge at least a fraction of the first air portion;

a second air outlet positioned on the top portion of the container to vertically discharge at least a fraction of the second air portion;

a first air moving system, the first air moving system including a first fan positioned in flow communication with the first air outlet to move at least a fraction of the first air portion from the first interior portion through the first air outlet; and

a second air moving system, the second air moving system including a horizontally situated second fan in flow communication with the second air outlet to move at least a fraction of the second air portion from the second interior portion, over the radiator, and through the second air outlet.

26. The portable power module of claim 22 wherein the first air inlet is positioned on one of the first or second side portions, wherein the second air inlet is positioned on one of the first or second side portions, and wherein the portable power module further comprises:

a first air outlet positioned on the top portion of the container to vertically discharge at least a fraction of the first air portion;

a second air outlet positioned on the top portion of the container to vertically discharge at least a fraction of the second air portion;

a first air moving system, the first air moving system including a first fan positioned in flow communication with the first air outlet to move at least a fraction of the first air portion from the first interior portion through the first air outlet, the first fan configured to receive electrical power from the generator;

a second air moving system, the second air moving system including a horizontally situated second fan in flow communication with the second air outlet to move at least a fraction of the second air portion from the second interior portion, over the radiator, and through the second air outlet, the second fan configured to receive electrical power from the generator;

a first variable speed frequency drive electrically interconnected between the generator and the first fan to adapt the first fan to the frequency of electrical power provided by the generator; and

a second variable speed frequency drive electrically interconnected between the generator and the second fan to adapter the second fan to the frequency of electrical power provided by the generator.