Resonant link inverters for trapezoidal flux electrically commutated machines

To increase their usability wind and kinetic-tidal generators and Electric Vehicles (EVs) require efficient conversion between mechanical and electrical energy. The brushless dc machine (BLDCM) is entirely suitable for such a task, and to exemplify its use this thesis details a high efficiency kinetic-tidal energy generator test system. To maximise the energy yield it uses a low solidity turbine, an efficient transmission system, a BLDCM generator, and a maximum power point tracker. BLDCM cogging torque is also addressed. Measured results are presented, with the measured efficiency of the water-turbine being 30%in real-world conditions. Although the BLDCM is an efficient energy converter, it requires power electronic control; the soft-switched Actively Clamped Resonant DC Link Inverter (ACRLI) is an ideal choice for such. This thesis details a complete mathematical analysis of the ACRLI topology, and develops formulae for all important voltages, currents, and timing. A complete list of loss formulae for all major components, including a MOSFET clamp device, is presented. These formulae can be used to optimally design ACRLIs, and an optimal design for a 10 kW EV is described. Since the inductor in a high power ACRLI is problematic, this thesis addresses large ferritecored inductor design, analysing hysteresis and eddy current core loss and Litz wire conduction loss. An optimal but non-realisable design is shown, followed by a near-optimal, realisable and economical very low loss inductor design; an inductor was fabricated in accordance with this design and its measured loss in resonant link operation, being less than 20W for the 10kW high current inverter, is consistent with theory. The BLDCM’s applicability in the general EV field has been questioned due to its rectangular torque versus speed characteristic. To modify this characteristic a voltage booster could be used. The ACRLI can provide such boosting with the addition of a few components, the main one being a rectifier grade thyristor, thus creating the Actively Clamped Resonant DC Link-Boost Inverter (ACRL-BI) topology. This new topology is analysed along with an optimal thyristor dv=dt snubber, a suitable current control method with minimum switching frequency, and a novel driver interface for EV use. A 10 kWACRL-BI prototype was built and measured results of resonant and boost operation are shown.

[1]  D. Macnaughton,et al.  Tidal stream turbine development , 1993 .

[2]  Kevin Barraclough,et al.  I and i , 2001, BMJ : British Medical Journal.

[3]  B.K. Bose,et al.  An improved resonant DC link invertor for induction motor drives , 1988, Conference Record of the 1988 IEEE Industry Applications Society Annual Meeting.

[4]  Bimal K. Bose,et al.  High-Frequency Link Power Conversion , 1977, IEEE Transactions on Industry Applications.

[5]  Deepak Divan,et al.  The Resonant DC Link Converter--A New Concept in Static Power Conversion , 1986, 1986 Annual Meeting Industry Applications Society.

[6]  Fred C. Lee,et al.  A high frequency model for Litz wire for switch-mode magnetics , 1993, Conference Record of the 1993 IEEE Industry Applications Conference Twenty-Eighth IAS Annual Meeting.

[7]  John Swenson.  The Specification, Design and Development of a Kinetic Energy Tidal Power Generator , 1996 .

[8]  Deepak Divan,et al.  Optimal discrete pulse modulation waveforms for resonant link inverters , 1988, PESC '88 Record., 19th Annual IEEE Power Electronics Specialists Conference.

[9]  Bimal K. Bose,et al.  A microcomputer-based control and simulation of an advanced IPM synchronous machine drive system for electric vehicle propulsion , 1988 .

[10]  J. C. Balda,et al.  Operating characteristics of MCTs in resonant DC link inverters , 1994, Proceedings of 1994 IEEE Industry Applications Society Annual Meeting.

[11]  Hamid A. Toliyat,et al.  Propulsion system design of electric and hybrid vehicles , 1997, IEEE Trans. Ind. Electron..

[12]  H. J. Beukes,et al.  Control complexities related to high power resonant inverters , 1996, PESC Record. 27th Annual IEEE Power Electronics Specialists Conference.

[13]  G. Venkataramanan,et al.  Design methodologies for soft switched inverters , 1988, Conference Record of the 1988 IEEE Industry Applications Society Annual Meeting.

[14]  P. Ziogas.  The Delta Modulation Technique in Static PWM Inverters , 1981, IEEE Transactions on Industry Applications.

[15]  Thomas M. Jahns,et al.  System design considerations for a high-power aerospace resonant link converter , 1993 .

[16]  T.G. Habetler,et al.  Performance characterization of a new discrete pulse modulated current regulator , 1988, Conference Record of the 1988 IEEE Industry Applications Society Annual Meeting.

[17]  J. D. van Wyk,et al.  An evaluation of resonant snubbers applied to GTO converters , 1989 .

[18]  T. Stuart,et al.  A study of IGBT turn-off behavior and switching losses for zero-voltage and zero-current switching , 1992, [Proceedings] APEC '92 Seventh Annual Applied Power Electronics Conference and Exposition.

[19]  Robert D. Lorenz,et al.  Dynamic analysis and experimental evaluation of delta modulators for field-oriented AC machine current regulators , 1990 .

[20]  Hideo Okayama,et al.  A new regenerative snubber circuit for large-capacity three-level GTO inverter systems , 1997 .

[21]  Ralf J. Sommer,et al.  Behaviour of IGBT modules in zero-voltage-switch applications , 1992, PESC '92 Record. 23rd Annual IEEE Power Electronics Specialists Conference.

[22]  Mehrdad Ehsani,et al.  Performance analysis of electric motor drives for electric and hybrid electric vehicle applications , 1996, Power Electronics in Transportation.

[23]  D. J. Patterson.  An efficiency optimized controller for a brushless DC machine, and loss measurement using a simple calorimetric technique , 1995, Proceedings of PESC '95 - Power Electronics Specialist Conference.

[24]  C. C. Chan,et al.  Novel wide range speed control of permanent magnet brushless motor drives , 1995 .

[25]  Stuart Bennett,et al.  Real Time Computer Control: An Introduction , 1988 .

[26]  A. Schellmanns,et al.  Modeling Litz wire windings , 1997, IAS '97. Conference Record of the 1997 IEEE Industry Applications Conference Thirty-Second IAS Annual Meeting.

[27]  Dj Patterson.  Recent Advances in the Design and Construction of Axial Flux Permanent Magnet Machines , 1996 .

[28]  R.W. De Doncker,et al.  Circuit utilization characteristics of MOS-controlled thyristors , 1989, Conference Record of the IEEE Industry Applications Society Annual Meeting,.

[29]  D.M. Divan,et al.  Characterization of GTOs for soft switching applications , 1988, Conference Record of the 1988 IEEE Industry Applications Society Annual Meeting.

[30]  T. M. Jahns,et al.  A new resonant link aircraft power generating system , 1993 .

[31]  R. D. De Doncker,et al.  A new single phase AC to DC zero voltage soft switching converter , 1990, 21st Annual IEEE Conference on Power Electronics Specialists.

[32]  M. Bartoli,et al.  Modeling Litz-wire winding losses in high-frequency power inductors , 1996, PESC Record. 27th Annual IEEE Power Electronics Specialists Conference.

[33]  Thomas A. Lipo,et al.  Power Conversion Distribution System using a Resonant High Frequency AC Link , 1986, 1986 Annual Meeting Industry Applications Society.

[34]  E. T. Calkin,et al.  Circuit Techniques for Improving the Switching Loci of Transistor Switches in Switching Regulators , 1976, IEEE Transactions on Industry Applications.

[35]  A. M. Tuckey,et al.  A kinetic energy tidal generator in the Northern Territory-results , 1997, Proceedings of the IECON'97 23rd International Conference on Industrial Electronics, Control, and Instrumentation (Cat. No.97CH36066).

[36]  Tore Undeland,et al.  Power Electronics: Converters, Applications and Design , 1989 .

[37]  D. J. Patterson.  High efficiency permanent magnet drive systems for electric vehicles , 1997, Proceedings of the IECON'97 23rd International Conference on Industrial Electronics, Control, and Instrumentation (Cat. No.97CH36066).

[38]  H. Mosebach,et al.  Design concepts and force generation in inverter-fed synchronous machines with permanent magnet excitation , 1984 .

[39]  E. Snelling.  Soft ferrites: properties and applications , 1969 .

[40]  Thomas A. Lipo,et al.  Field oriented control of an induction machine in a high frequency link power system , 1988, PESC '88 Record., 19th Annual IEEE Power Electronics Specialists Conference.

[41]  Johann W. Kolar,et al.  New lossless turn-on and turn-off (snubber) networks for inverters, including circuits for blocking voltage limitation , 1984, 1984 IEEE Power Electronics Specialists Conference.

[42]  Charles R. Sullivan.  Optimal choice for number of strands in a litz-wire transformer winding , 1997 .

[43]  D. M. Divan,et al.  Delta modulation strategies for resonant link inverters , 1987, IEEE Power Electronics Specialists Conference.

[44]  Chas.P. Steinmetz,et al.  On the law of hysteresis , 1984, Proceedings of the IEEE.

[45]  G. E. Taylor,et al.  Computer Controlled Systems: Theory and Design , 1985 .

[46]  Tadashi Ashikaga,et al.  Novel motors and controllers for high-performance electric vehicle with four in-wheel motors , 1997, IEEE Trans. Ind. Electron..

[47]  E. Kreyszig,et al.  Advanced Engineering Mathematics. , 1974 .

[48]  George C. Verghese,et al.  Principles of power electronics , 1991 .

[49]  H.-R. Chang,et al.  Performance of 500 A, 450 V parallel MOS-controlled thyristors (MCTs) in a resonant DC-link circuit , 1990, Conference Record of the 1990 IEEE Industry Applications Society Annual Meeting.

[50]  Power MOSFETs Excel in Synchronous Rectifier Applications , 2022 .

[51]  Karl Johan Åström,et al.  Computer-Controlled Systems: Theory and Design , 1984 .

[52]  Bimal K. Bose.  A high-performance inverter-fed drive system of an interior permanent magnet synchronous machine , 1987 .

[53]  Deepak Divan,et al.  Zero-switching-loss inverters for high-power applications , 1989 .

[55]  Yim-Shu Lee,et al.  Simple approximations of the DC flux influence on the core loss power electronic ferrites and their use in design of magnetic components , 1997, IEEE Trans. Ind. Electron..

[56]  R.W. De Doncker,et al.  Characteristics of MOS-controlled thyristors under zero voltage soft-sw-ing conditions , 1990, Conference Record of the 1990 IEEE Industry Applications Society Annual Meeting.

[57]  Jan Abraham Ferreira,et al.  Improved analytical modeling of conductive losses in magnetic components , 1994 .

[58]  Ned Mohan,et al.  Non-dissipative Undeland snubber for electric vehicle drive inverters using GaAs anti-parallel diodes , 1996, Proceedings of International Conference on Power Electronics, Drives and Energy Systems for Industrial Growth.

[60]  T. Durbaum,et al.  Calculating core losses in transformers for arbitrary magnetizing currents a comparison of different approaches , 1996, PESC Record. 27th Annual IEEE Power Electronics Specialists Conference.

[61]  D. A. Torrey,et al.  An alternative bus clamp for resonant DC-link converters , 1994 .

[62]  G. H. Chen,et al.  Design of a permanent-magnet direct-driven wheel motor drive for electric vehicle , 1996, PESC Record. 27th Annual IEEE Power Electronics Specialists Conference.

[63]  John Ofori-Tenkorang.  Permanent-magnet synchronous motors and associated power electronics for direct-drive vehicle propulsion , 1996 .

[64]  R. Spee,et al.  The design and development of an axial flux permanent magnet brushless DC motor for wheel drive in a solar powered vehicle , 1994, Proceedings of 1994 IEEE Industry Applications Society Annual Meeting.

[65]  M. D. Hooven,et al.  Electrical engineering as it will be , 1956, Electrical Engineering.

[66]  P. Sewell,et al.  High precision calorimetry for the measurement of the efficiency of induction motors , 1998, Conference Record of 1998 IEEE Industry Applications Conference. Thirty-Third IAS Annual Meeting (Cat. No.98CH36242).

[67]  A. Brockmeyer.  Experimental evaluation of the influence of DC-premagnetization on the properties of power electronic ferrites , 1996, Proceedings of Applied Power Electronics Conference. APEC '96.

[68]  A. Brockmeyer,et al.  Frequency dependence of the ferrite-loss increase caused by premagnetization , 1997, Proceedings of APEC 97 - Applied Power Electronics Conference.

[69]  Deepak Divan,et al.  Loss mechanisms in IGBTs under zero voltage switching , 1992, PESC '92 Record. 23rd Annual IEEE Power Electronics Specialists Conference.

[70]  Deepak Divan,et al.  System design issues for resonant DC link inverter based drives , 2002 .

[71]  A Betz.  Windmills in the Light of Modern Research , 1928 .

[72]  Pradeep Sood,et al.  A versatile power converter for high frequency link systems , 1987, 1987 IEEE Applied Power Electronics conference and Exposition.