Department of Electrical Engineering Research and Development of Machine Drives and Power Conditioning Strategy and its Development for Electric Vehicles From 1999 to 2009 Prof. Eric Cheng Department of Electrical Engineering

Four RGC projects leading to Current Accomplishments on Electric Vehicles From 1999 to 2002 Future Switched Reluctance Machine Drives and Associated Power Conditioning (PolyU5085/98E) From 2003 to 2005 Development of the Future Power Conversion Techniques Using Adaptive Control and Integrated Magnetics (PolyU 5103/01E) From 2004 to 2007 Design and Modeling of An Integrated Fuel Cell and Energy Storage System to Enhance Power System Performance and Reliability (PolyU 5245/04E) From 2007 to 2009 Formulation of DC Energy Factor and Its Implication on Control Method for High Efficiency Power Electronics Conversion System (PolyU 5136/06E)

Future Switched Reluctance Machine Drives and Associated Power Conditioning Strategy RGC: PolyU5085/98E) (1999~2004) Outcome Proposition of four models of SRM drives Investigation of the effects of control & output parameters upon power factor in SRM drives Proposition of new method to design controllers with good power factor Development of schemes to improve the power factor in SRM drives Development of a soft-switching power conditioning strategy a) the interpolation model based on bicubic spline, b) the analytical model of SRM based on the two-dimensional lest squares, c) the hybrid model based on bicubic spline and bilinear spline, and d) the multi-phase model with mutual coupling b) The control parameters include the turn-on angle, turn-off angle, freewheeling angle, the duty cycle and chopping modes under voltage PWM control, the reference current, hysteresis band and chopping modes under current hysteresis control, input voltage, dc link capacitance. c) good power factor are that the proper switching angles are determined, d) One of which is based on the real-time optimization of the switching angles. The other is based on the off-line Hooke-Jeeve pattern optimization of the switching angles.

Future Switched Reluctance Machine Drives and Associated Power Conditioning Strategy (RGC: PolyU5085/98E) (1999~2004) Published papers 10 Journal papers 11 Conference papers

Simulation of Switched Reluctance Motor Drives Using Two-dimensional Bicubic Spline IEEE Transactions on Energy Conversion A two-dimensional bicubic spline interpolation is used to describe the nonlinear magnetic characteristics in switched reluctance motors

Influences of Outputs and Control Parameters upon the Power Factor of SRM Electrical Components and Systems Establish a comprehensive SRM drives design to realize good controllers with high power factor

An Algorithm for Solving Initial Value Problems of Mutual-Coupling Electrical Components and Systems The non-linear modeling of multiphase switched reluctance motors has been developed to simulate SRM accurately.

Trigonometry-Based Numerical Method and Self-Training Numerical to Compute Nonlinear Magnetic Characteristics IEEE Transactions on Magnetics Provide a valuable approach for design, simulation, sensorless drive and control as well as torque prediction of SRMs

Improvement of Power Factor Drives through Optimizing the Switching Angles Electrical Components and Systems Novel control strategy to improve the power factor of SRM drives is proposed and two schemes to improve its power factor are developed.

Correlation of Modeling Techniques and Power Factor IEE Proceedings Electric Power Applications Unified modeling on sensorless control and power factor improve-ment of switched reluctance machine drives has been proposed

Position Stepping Method IEEE Transactions on Energy Conversion Based on 2-D bicubic spline and 2-D bilinear spline, the proposed position stepping method is used to predict the performances of switched reluctance motor (SRM) drives.

AC Resistance of Multistranded Conductor Inductors with Multilayers IEEE Transactions on Magnetics Generalized solution for AC resistance Suitable for multi-layers and multi-strands

DC-DC Power Conditioning IET Proceedings/Letter, IEEE Trans Ind. Elec, EPCS Switched-capacitor power conditioning A family of circuit topologies Improve the current shaping of the switched-reluctance drive

Development of Future Power Conversion Techniques Using Adaptive Control and Integrated Magnetics (RGC: PolyU5103/01E) (2002~2004) Published papers 7 Journal papers 5 Conference papers

Project Outcomes Developed a new analytical method for integrated magnetics Developed the passivity control method for power converters Developed a new Quasi Current Mode Control strategy for DC-DC power converters

Integrated magnetics version of Forward converter IEE Proceedings EPA Integrated magnetics version of Forward converter Developed a number of integrated magnetic circuits Examine the efficiency performance vs energy processing Boost-flyback converter

Passivity control Developed an adaptive controller for phase-shifted control based on a passivity control theory IEE Proceedings EPA Conventional new method Improvement of output response using PBC

Two Axis Indirect Current Mode Control IEEE Trans Power E A novel indirect current mode control system with voltage compensation for the control of phase shifted resonant converters Regulating the quadrature components of the voltage applied to the resonant circuit Controlled PSRC with new structure Phasor diagram of the resonant circuit

Design and Modeling of An Integrated Fuel Cell and Energy Storage System to Enhance Power System Performance and Reliability in Energy Storage Systems (PolyU 5245/04E) (2004~2007) Outcomes Developed a mathematic model of both dynamic and state-state for fuel cell Study fuel cell with magnetic energy storage Propose a new family of ZCS and ZVS power conditioners Published papers 2 Journal papers 2 Conference papers Fuel cell vehicle

Unified Mathematical Modelling of Steady-State and Dynamic Voltage-Current Characteristics for PEM Fuel Cells Electrochemical Acta Developed a novel approach for optimization of the operating points of fuel cells and design of power conditioning units, simulators, and system controllers.

ZVS and ZCS Converters Work well with fuel cells IET Power Electronics Work well with fuel cells Has been applied to fuel cell vehicle Zero-current and zero-voltage switching are realized Family of circuits developed Zepic Buck-boost

Formulation of DC Energy Factor and Its Implication on Control Method for High Efficiency Power Electronics Conversion System (PolyU 5136/06E) (2007~2009 on-going) Developed the concept and a new definition of the energy factor for DC-DC power conversion Developed an energy factor control method Improved the efficiency of converters via energy factor Published papers 2 Submitted Journal papers 2 Conference papers

Boundary condition analysis Developed the boundary condition for Switched-mode converter Developed the formulation of energy factor under boundary condition

Generalized analysis for energy storage Developed a generalized energy approach in storage devices Developed a systematic study on the characteristics of storage devices with duty ratio Provide techniques to select the optimal power converter for various power applications Non-active instantaneous power Energy Factor Under CCM Input energy factors under CCM

The Development of Electric Vehicles Through the RGC projects, the team has accomplished the following technological developments: SR motor design SR motor drive High frequency magnetic design Family of switched mode high power converters Soft-switching power conditioner Fuel cell power conditioner Energy storage device Optimal Performance of converters

Motor and Drives Electric Vehicle Development Integration of motor and wheel Minimize mechanical interfacing Realize in-wheel motor vehicle SRM driver SRM Finite element model

Power Converter Driver to LED and HID Lightings Developed LED driver Developed HID lamp driver Installed on commercial vehicle HID lamp LED Headlight LED and HID headlight LED lamp and driver HID lamp ballast LED Tail light

Charging system High power fast charger CLP Power charging system in Hong Kong Battery Management System Simple plug-in EV

In-wheel motor for 4-wheel drive 1st Electric Vehicle using in-wheel reluctance drives

DC-DC Power Design for Electric Vehicle 1st commercial vehicle in HK Conversion to EV

Summary Research and development of Power Electronics technology in Switched Reluctance Machine drives, DC-DC Power Conversion, Magnetics and Energy Storage with advanced design and control techniques have been developed. Arising from RGC Projects, 20 journal papers and numerous conference papers have been published. Applications to electric vehicles are most prominent Extension of the research to commercial products and collaborates with a number of companies including CLP, Tenpao, Shun Hing Power, Fok Yin Tung Foundation, Hopewell,…

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