Extend the KMB project Power Electronics for two more years (2011-2012)

• Gain more experiences from long-term testing of developed test objects, and especially long term stability of semiconductor in liquid insulation.
• A more thorough examination of liquid insulations for Pressure Tolerant Power Electronics.
• Different liquid candidates.
• Need for dielectric coating (e.g. due to contaminations) and alternatives.
• Combined insulation materials and interface materials.
• Insulation requirements for higher voltages (10kV+).
• Quantifying electric stress on power converters and motors in liquid environment.
• Exploit results from PhD work produced in 2011 and 2012.

 A pressure tolerant demo placed on an existing subsea field (KMB, BIP or Demo 2000 project)

• Before subsea installation or in parallel, the demo can undergo a test programme in pressure vessel.   Pressure Tolerant Demo

 A real pressure tolerant converter application (BIP or Demo 2000 project)

• Prototype in the power range 100kW-1MW.
• E.g. a converter system for Direct Electric Heating (DEH).

Quantifying electric stress on power converters and motors in liquid environment (KMB or BIP project).

Potential problems related to subsea electric motor operation is not covered by any of the ongoing Subsea Power Supply projects. This will be a new project exploiting results from all three ongoing subsea projects and other related projects

Transient analysis work based on results from the KMB project Power Systems

• Transient voltage stress on windings depending on converter topology, e.g. on converter filter reactors and transformers.
• Motor bearing current stress.
• Excitation of mechanical vibrations.
• Many other potential problems due to liquid replacing air.

Experiments with a Variable Speed Drive (VSD), comprising both 2- and 3-level converter and a asynchronous motor running in liquid

• 2- and 3-level converters are available from another possible cooperating KMB project.
• Hardware and software for digital motor control is available from an internal SINTEF project.
• Running the converter controlled motor in appropriate liquids.
• Expose potential problems and propose remedies.

Experiments with high voltage VSD modules (10kV DC-link) comprising 2- and 3-level phase-legs, and a passive phase load emulating a 6.6kV motor phase

• A high voltage phase-leg can be made available by cooperation with another KMB project .
• Experiments with 6.6kV phase-leg module in liquid and under high ambient pressure (300 bar+).
• Expose potential problems and propose remedies.

Power Electronics for increasing Offshore Power System Efficiency (KMB or BIP project)

Energy efficiency improvements Energy supply from onshore power supply, offshore wind power etc. Optimizing operation, heat recovery Subsea separation Reduced emission from power generation (gas turbines)

Power Electronics for downhole applications (KMB or BIP project)

• Temperature tolerant (200oC) power electronics in addition to pressure tolerant.
• Silicon Carbide power semiconductors.
• Select application ® circuit design ® make prototype ® testing ® demo.
• Internal project 2009: Qualified high temperature tolerant components (200o+) are found.
• We are ready for circuit design.