Roy Nilsen

Professor Institutt for elkraftteknikk
+4773594285 +4795178363
Eno*e-417, O.S. Bragstads pl 2e

Bakgrunn og aktiviteter

Roy Nilsen, born 1956, is professor in Electric Drives at the Department of Electric Power Engineering at NTNU. He holds an MSC and PhD in Electrical Engineering from NTH/NTNU  1983/84 and 1987, respectively. He was professor in Electric Drives in the period 1996-2006 and in again in fulltime position as professor since April 2017.


He has more than 30 years experience within R&D in the field of Electrical Drives, both in industrial- and marine drives. In the period 1984 until 1987 he was part-time employed by Norwegian Electric Brown Boveri (NEBB), today Asea Brown Boveri (ABB). From 1987 until 1996 he was full-time employed at ABB. In 1988/89 he was working at ABB Drives in Turgi, Switzerland. In 1993/94 he was Program Manager for Automotive Drives, R&D , AC Drives in ABB. In the years 1995-1996 he was Senior Research Manager at ABB Corporate Research, Norway. From 1996-2006 he was a professor within Electric Drives at NTNU.  In the period 2001 until 2006, he was part-time employed at Aker/Wärtsilä and was responsible for the motor SW development in the Power Drive development (800-5000 kW 690 V marine drives). From 2006-2017 he was full-time employed at Wärtsilä/The Switch. In addition, he was a technical advisor at Smart Motor from 2001 to 2013. Since 1993 he has been one of the Norwegian members in the International Steering Committee (ISC) for European Power Electronics conference (EPE).


Fields of research have been sensorless control, motor control in general, resonance converters for electrostatic filters and sub-marines, marine drives and on-board DC-distribution. He has also worked with modelling and life-time calculation for batteries used on-board ferries and Offshore Supply Vessels.


Books/Lecture Notes/ PhD thesis:


Nilsen Roy:                       Elektriske motordrifter. Lecture Notes , NTNU Trondheim 2004.

                                         211 pages - 3rd edition

Nilsen Roy:                       Electric Drives. Lecture Notes , NTNU Trondheim 2016.

                                         211 pages - 4th edition.

                                      Nilsen Roy:            Modeling, identification and control of an induction   machine

                                                                   Dr.-Ing. Thesis NTH, Trondheim – 1987


Selected academic and professional publications:


[P1]       Maharjan M.,      :            Implementation of Synchronous Optimal Modulation in

Undeland T.M, Nilsen R.  Field Programmable Gate Array.            Proceedings of the 5th International    Conference on Power and Energy Systems (ICPS), 28-30 October 2013, Kathmandu, Nepal


[P2]       Gjerde S.S, Ljøkelsøy K. , : A Modular Series Connected Converter Structure Suitable for a .

             R. Nilsen, T. Undeland       High-Voltage Direct Current Transformerless Offshore Wind

                                                       Turbine.    Journal:  Wind Energy 2013


[P3]       Nilsen R. , Sørfonn I         : Hybrid Power Generation Systems, Invited paper for 

                                                        EPE 2009, Barcelona


[P4]       Gullvik W;  Nilsen R.,      : Active Damping of Resonance Oscillations in LCL-filter Based on

             Norum, L                            Virtual Flux and Virtual Resistor. EPE2007 Riga


[P5]       Øvrebø S;  Nilsen R.        : New Self Sensing Scheme Based on INFORM, Heterodyning

                                                        and Luenberger Observer, IEMCD, Madison, Wisconsin,

  1 - 4 June 2003


[P6]       Tomta  G.; Lund, R ;        : Calculation of AC side harmonic losses in three-level converters

              Nilsen R.                           Converters.     EPE 2003, Tolouse, France


[P7]       Lund, R ; Beverfjord  J.    : Reduced Analytic Power Loss Expressions for Diode Clamped

             Øvrebø  S; Nilsen R.          Converters.     EPE-PEMC 2002 Dubrovnik.


[P8]       T. Melaa, A.K. Ådnanes,  : Evaluation of resonant converters for increased softswitching

             K. Øye, T.F. Nestli ,           range.   EPE97- Trondheim

R. Nilsen, P. Ranstad 


[P9]       R. Nilsen ,                        : Direct Torque Controlled induction motor drive utilized in an

             T. Kasteenpohja                  electrical vehicle

                                                       EPE'95 - Sevilla, Spain


[P10]     A.K. Ådnanes, R. Nilsen , : Efficiency Analysis of Electrical Vehicles, with Emphasis

             R. Løken, L. Norum           on Efficiency Optimized Excitation

                                                       IEEE IAS annual meeting , Tororonto, Oct. 02-08. 1993


[P11]     T.F. Nestli,                       : Evaluation and comparison of predictor models for rotor flux

             R. Nilsen                            calculation in induction motors

                                                       IEEE PESC'94- Taipei, Taiwan


[P12]     R. Nilsen ,                        : New Reduced-order observer with parameter adaption for

             M.P. Kazmierkowski          flux estimation in induction motors

                                                       IEEE PESC'92-Toledo Spain



[P13]     R. Nilsen ,                        : Reduced-order observer with parameter adaption for fast rotor

             M.P. Kazmierkowski          flux estimation in induction machines

                                                       IEE Proceedings, Vol.136, Pt.D, No. 1, January 1989

(Awarded paper)


[P14]     K. Vangen, T. Melaa,       : Efficient high-frequency soft-switched power converter with

             S. Bergsmark, R. Nilsen      signal processor control

                                                       INTELEC'91 - Nov.1991           


[P15]     G. Tomta , R. Nilsen:        Analytical equations for three level NPC converters.

                                                     EPE'2001 - Graz, Austria



Vitenskapelig, faglig og kunstnerisk arbeid

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Del av bok/rapport

  • Gullvik, William; Norum, Lars Einar; Nilsen, Roy. (2007) Active Damping of Resonance Oscillations in LCL-Filters Based on Virtual Flux and Virtual Resistor. EPE 2007 12th European Conference on Power Electronics and Applications.