Subsea processing is currently the most exiting and growing applications in oil and gas industry with annual growths over 20% annually. The concept is to take the essential equipment such as pumps, compressors, and some processing typically found on offshore platforms, marinized it for the extreme maritime environment and placed it on the ocean floor.
Subsea pumps and compressors are integrated and hermetically sealed. Current pumps and compressors utilize conventional induction electric motors which are large, heavy, inefficient and impose very high mechanical losses due to the friction of operating in fluids or very high gas pressures. These mechanical losses reduce the overall system efficiencies by around 30% and limit power levels to around 2MW.
DDS permanent magnet motors offer significant benefits to subsea pump and compressor applications which not only increase the total system efficiency but also allow the pumps and compressors to deliver much more power (+ 20MW) without increasing mechanical losses. Benefits of DDS machines for subsea applications can be summarized as:
- Smaller rotor diameter
- Larger air gaps
- Higher power density machines
- Higher shaft speeds at lower tip speeds
- Passive and active magnetic bearings
- Constant torque through out the operating speed range
- Very low rotor losses
- Canned rotor design
DDS permanent magnet motors have found its perfect fit where all of its attributes are well received and necessary for subsea applications.
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