FreeSpin® In-line Turboexpander Generator

Sapphire Technologies’ FreeSpin® In-line Turboexpander (FIT) Generator uses advanced magnetic technologies that help reduce gas pressure and provide a way to capture the energy lost in pressure reduction.

The FIT systems’ generators extract kinetic energy from the pressure reduction at the various stages of gas processing and distribution and allow for the generation of electricity with no added pollution.

Zero Emissions

The FreeSpin® In-line Turboexpander uses zero fuel and produces zero emissions. The simplicity of the FIT design enables a cost-effective solution for power generation.

Low Maintenance

The FreeSpin® In-line Turboexpander runs on magnetic bearings and is hermetically sealed into a single unit, eliminating the need for a gearbox and a lubrication system. It does not require dynamic seals, which often cause environmental hazards upon failure.

Efficient

The high-speed permanent magnet motor generator is simply constructed and operates with very little losses. The highly efficient motor generator has variable speed and load capabilities and provides a greater power density and a smaller footprint than conventional systems.

Reliable

Active magnetic bearings offer significant advantages over conventional bearings in terms of footprint, operating efficiency, losses, remote monitoring capabilities, power consumption and reliable performance in harsh environments.

Components

Inlet Guide Vanes

The inlet guide vanes direct gas-flow toward the expander wheel at the optimal angle. These are designed much like a water wheel, but the concentric cavity gradually increases in cross section from inlet to outlet allowing for expansion of the gas. Radial turboexpanders are designed with axial flow inlets and radial flow outlets such that the gas is expanded radially through the turbine wheel.

Expander/Turbine Wheel

High pressure gas enters through the expander wheel where the kinetic energy is extracted from the gas stream. The gas leaves the expander wheel at a lower pressure and temperature. The turbine wheels are typically designed to optimize aero efficiency. Application variables affecting turbine wheel design include inlet/outlet temperature, inlet/outlet pressure, volumetric flow rate and fluid characteristics. When the pressure ratio is too large to reduce through a single stage, multi-stage turboexpanders are required.

High-speed Permanent Magnet Generator

The permanent magnet synchronous generator is utilized in a high-speed, direct-drive turboexpander for power generation. The permanent magnet (PM) generator in the FreeSpin® In-line Turboexpander is directly coupled to the turbine shaft and converts the rotational mechanical energy from the turbine into useable electricity via the variable speed drive. The direct-drive, permanent-magnet generator has variable speed and load capabilities and can run at speeds up to 30,000 rpm. The patented technology also offers high-speed operation, simplified controls for power generation and no maintenance.

The PM generator consist of two basic parts. A stator coil powered by an alternating current to create an electric field and a rotor made of special magnetic material that rotates within that field. The high-speed PM generators utilize the latest technology in high-strength rare-earth magnetic materials to achieve high efficiency and a high-power density. In comparison to other generator types, the PM generator has higher efficiency therefore improving the overall system efficiency and has higher power density allowing for a compact size at all power levels.

Active Magnetic Bearings

The magnetic bearings in the FreeSpin® turboexpander are highly reliable, reduce operating costs and expand machine operating parameters. An AMB allows the dynamic components of the FIT to operate in a levitated condition, consuming very little energy and eliminating maintenance as compared to conventional bearings. The AMBs are controlled by magnetic bearing controller, which controls and monitors conditions of the AMB system, allowing complete control of the system and adaptive control under varying load conditions.

The AMBs have built-in diagnostics capabilities that provide users with insight into the generator’s health and performance by monitoring axial and radial load conditions. With a connection to the computer, identifying, analyzing and archiving the health and historical performance of the machine are all possible remotely. This protects the machine and provides process characteristics enabling diagnostics of the gas flow. The graphical user interface (GUI) provides insight into all aspects of magnetic bearing and machine performance and can be utilized to view real-time data, such as changes in mass flow, temperature of internally powered components and density without any additional equipment.

Components

Inlet Guide Vanes

The inlet guide vanes direct gas-flow toward the expander wheel at the optimal angle. These are designed much like a water wheel, but the concentric cavity gradually increases in cross section from inlet to outlet allowing for expansion of the gas. Radial turboexpanders are designed with axial flow inlets and radial flow outlets such that the gas is expanded radially through the turbine wheel.

Expander/Turbine Wheel

High pressure gas enters through the expander wheel where the kinetic energy is extracted from the gas stream. The gas leaves the expander wheel at a lower pressure and temperature. The turbine wheels are typically designed to optimize aero efficiency. Application variables affecting turbine wheel design include inlet/outlet temperature, inlet/outlet pressure, volumetric flow rate and fluid characteristics. When the pressure ratio is too large to reduce through a single stage, multi-stage turboexpanders are required.

High-speed Permanent Magnet Generator

The permanent magnet synchronous generator is utilized in a high-speed, direct-drive turboexpander for power generation. The permanent magnet (PM) generator in the FreeSpin® In-line Turboexpander is directly coupled to the turbine shaft and converts the rotational mechanical energy from the turbine into useable electricity via the variable speed drive. The direct-drive, permanent-magnet generator has variable speed and load capabilities and can run at speeds up to 30,000 rpm. The patented technology also offers high-speed operation, simplified controls for power generation and no maintenance.

The PM generator consist of two basic parts. A stator coil powered by an alternating current to create an electric field and a rotor made of special magnetic material that rotates within that field. The high-speed PM generators utilize the latest technology in high-strength rare-earth magnetic materials to achieve high efficiency and a high-power density. In comparison to other generator types, the PM generator has higher efficiency therefore improving the overall system efficiency and has higher power density allowing for a compact size at all power levels.

Active Magnetic Bearings

The magnetic bearings in the FreeSpin® turboexpander are highly reliable, reduce operating costs and expand machine operating parameters. An AMB allows the dynamic components of the FIT to operate in a levitated condition, consuming very little energy and eliminating maintenance as compared to conventional bearings. The AMBs are controlled by magnetic bearing controller, which controls and monitors conditions of the AMB system, allowing complete control of the system and adaptive control under varying load conditions.

The AMBs have built-in diagnostics capabilities that provide users with insight into the generator’s health and performance by monitoring axial and radial load conditions. With a connection to the computer, identifying, analyzing and archiving the health and historical performance of the machine are all possible remotely. This protects the machine and provides process characteristics enabling diagnostics of the gas flow. The graphical user interface (GUI) provides insight into all aspects of magnetic bearing and machine performance and can be utilized to view real-time data, such as changes in mass flow, temperature of internally powered components and density without any additional equipment.

Engineering Support, Installation and Maintenance Services

Sapphire Technologies supports the commissioning process for the company’s FreeSpin® In-line Turboexpander systems after installation, including piping, plumbing and wiring.

The commissioning process checks the installation, prepares the unit for start-up, starts the unit and trains the site user on how the system works.

Though there is very little maintenance required for the FreeSpin® system, Sapphire Technologies supports maintenance needs as required.

The primary maintenance requirement for the unit is the periodic cleaning of the air filters, which is typically completed by the user. The FreeSpin® turboexpander system can be controlled and diagnosed remotely via the magnetic bearing controller and power electronics.