Dr Shawn Nielsen

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Program Lead - Applied superconductivity

Doctor of Philosophy (University of The Witwatersrand, Johannesburg)

BSc (Eng) WITS 1990

PhD (Eng) WITS 2002

1991-2001

  •  University of the Witwatersrand Johannesburg, South Africa
    • Professional Assistant
    • Junior Research Officer

2001-2006

  • Eskom Enterprises TSI now Eskom Holdings, Resources and Strategies C,R&D group.
    • Senior Engineer (PPP)
    • Chief Consultant (SS2)

2006-2010

  • Nu-Lec Industries now Schneider Electric Australia, Power division recloser solutions.
    • Medium Voltage Technology Specialist

2010 to present

  • Queensland University of Technology
    • Senior Research Fellow
    • Senior Lecturer

Projects

Additional information

Teaching

  • EGB241 : Electromagnetics and Machines
  • EGB341 : Energy Supply and Delivery
  • SEB701 : Work Integrated Learning
  • EGH454 : Power Systems Management with Renewable & Storage Resources
  • ENB454 : Power Systems Management
  • ENB453 : Power Equipment and Utilisation
  • ENB245 Introduction to Design and Professional Practice
  • Academic coordinator of the Postgraduate Electricity Supply Training Course (PESTC).

Research

  • Modeling of the V-I characteristics of high temperature superconductors in the presence of high magnetic fields.
  • Measurement of real-time winding movement in large power transformers using dynamic vector network analyses.
  • On-line dielectric response measurements on large power transformers.
  • Design and construction of SMALA (Switch Mode Assisted Linear Amplifier) voltage sources for  use in dielectric testing.
  • The use of restrikes in vacuum switchgear as a diagnostic tool.
  • Performance of SF6 insulated co-axial gaps under disconnector generated Very fast Transience’s.
  • Breakdown of co-axial gaps insulated with SF6/N2 mixtures under power frequency voltages.
  • 10kV shielded impulse voltage generator used for high voltage divider calibration and response certification.
  • Use of an SF6 GIS voltage transformer for the synthetic generation of Very Fast Transience’s in GIS.
  • Design and construction of a 100kA 4/10μs lightning current impulse generator.
  • Design, construction and calibration of a capacitive voltage divider for the measurement of Very Fast Transience’s in GIS.
  • Design, construction and calibration of numerous voltage dividers up to 1MV peak including resistive, capacitive and mixed dividers.
  • Ultra-High Frequency (UHF) Partial Discharged (PD) detection method in Gas Insulated Switchgear (GIS) under Lightning Impulse (LI) Voltage excitation.
  • Detection of corona activity in SF6 and air using an image intensifier and a photo multiplier.
  • Application of the UHF PD detection method to power transformers for the detection of defects and tap changer arcing.
  • Modelling of the electromagnetic field on the earth’s surface due to geomagnetic storms.

Supervision

  • Supervised 2 successful PhD candidates:
    • Shui-Cheong Kam (2012) Assessing of Circuit Breaker Restrike using Computer Simulation and Wavelet Analysis.
    • Xu Yang (2015) Enhancements to Dielectric Response Measurements of Oil-paper Insulation for Online and Offline Applications.
    • Supervised numerous (70+) final year projects.

Industrial:

  1. Design of outdoor pole mount Recloser and Load Break switches up to and including 38kV:
    • Dielectric design.
    • Short circuit forces.
    • Termination design.
    • Switching medium.
    • Thermal design.
    • Molding of Epoxy components.
    • External insulation design and testing for polluted conditions.
    • Pressure rise determination in power equipment due to internal arc events.
    • Thermal compensation of imbedded capacitive voltage sensors for improved temperature range accuracy.
    • Current transformer design.
  2. Failure investigation and reporting:
    • Dielectric and switching failures in Gas Insulated Switchgear up to and including 765kV.
    • Dielectric and switching failures in Reclosers and Load Break switches up to 38kV.
  3. High Voltage Engineering and the associated testing of high voltage equipment:
    • Properties of insulating dielectrics:
      • Comparative study of the performance of Cycloaliphatic epoxy and Hydrophobic epoxy for outdoor equipment using an in-house constructed salt fog chamber.
      • Comparative study of filling compounds for “wet” terminations.
      • Study into the performance of silicone over molding of epoxy for outdoor equipment.
      • Environmental effects of SF6.
      • Development of strategies and best practice for utility’s using SF6.
      • Handling, recycling and disposal of SF6 and associated by-products.
    • Test voltage/current generation and measurement:
      • Determination of the core material of current transformers from standard IEC performance measurements as a quality control tool.
    • Diagnostics of power equipment:
      • Diagnostics of GIS using gas analyses.
      • Leak detection in SF6 filled equipment using infrared background scattering absorption imaging.
      • Detection of fires under high voltage power lines using corona induced noise.
      • Detection of faults in power cables using frequency domain reflectometry techniques.
    • Partial discharge detection and interpretation.
      • Detection of partial discharge activity in power equipment using low cost microwave C and Ku band low noise block down-converters.
      • Partial discharge testing in a production environment as a quality control tool.
    • Electric and magnetic field modelling as well as coupled multi-physics modelling:
      • Glass cap and pin insulator strings under polluted conditions.
      • Dielectric design of epoxy Reclosers with vacuum interrupters.
      • A capacitance change of CVT’s embedded in epoxy bushings due to thermal heating.
      • Electric field stresses on silicone rubber terminations for pole mount switchgear.
      • Modelling of electric and magnetic fields associated with High Voltage transmission lines.
      • Written numerous programs in Matlab to calculate the electric and magnetic fields along transmission lines.
    • High voltage laboratory design and specification.
    • Electrical safety during high voltage and high current testing.