Turbo-expander / Generator Packages

The energy extracted from a gas expanding across the turbine can be converted into electric power by connecting the load side of the expander shaft to a generator. The Expander/Generator arrangement is typically available in following three configurations:

  • Expander / Gearbox / Generator
  • Expander / Generator
  • Expander / High Speed Generator

Expander / Gearbox / Generator

In most cases, the operating speed of the expander will be at a higher RPM than the operating speed of the generator. It is therefore necessary to utilize a speed reduction gearbox to facilitate appropriate coupling speed.

In one such configuration, the high speed expander shaft is connected to a high speed coupling that transmits the torque to a speed reduction gearbox. The gearbox is then coupled to the generator. This configuration is typically used in medium to high power applications.

Expander / Generator

In most cases, the operating speed of the expander will be at a higher RPM than the operating speed of the generator. It is therefore necessary to utilize a speed reduction gearbox to facilitate appropriate coupling speed.

In another such configuration, the expander wheel is directly mounted on a shaft that also serves as the high-speed gearbox pinion eliminating the high-speed coupling. As with the Expander/Coupling/Gearbox/Generator, this configuration is also used in medium to high power applications.

Expander / High Speed Generator

In a third configuration, the expander wheel is directly mounted on a shaft that also serves as the high-speed generator’s shaft, eliminating the gearbox entirely. This configuration is limited to the power capacity of high-speed generators and is typically used in low to medium power applications.

The sizes 30-160 to 50-660 as indicated above can be combined with an alternator to form  a turbo-expander / generator package.