Electric Vehicle Entrepreneurs Thursday 9th March 2012
What is the Radial Flux Laboratories business• RFL designs high efficiency, low cost electric motor/generators and electronic drives suited to a multitude of applications that are - half the weight and cost of conventional motors or generators - easily manufactured, in many cases by standard automated winding machinery, requiring no special components or materials - have efficiencies in the 90s% range• RFL provides under license -ready-to-manufacture designs -supply complete product to order• RFL typically licenses applications of the technology for specific market applications 2
RFL has developed 2 technology platforms, eachcapable of multiple end use applications• Dual stator with rectangular permanent magnet rotor which can be configured for - wind turbine generator - small inverter genset - large inverter genset - industrial electric motors - electric vehicle and bike motor/generator• Single stator design with flat permanent magnets -inverter less small gensets -large inverter less gensets 3
Radial Flux Laboratories – Development History 14 Years Research and Development of concepts to proven productFull encapsulation of 85% volume reduction permanent magnet 10% higher power Manufacturing complexity but principle successful 4
The RFL Dual Stator concept met manufacturabilityobjectives and has been developed to apply to a widerange of motor and generator product applications 5
Radial Flux Labs has developed a unique, optimized stator-rotor architecture•New design of copper stator elements•New permanent magnet configuration•Patented Rotor Design•Maximum magnetic flux - higher power, greater efficiency, less weight Conventional 20kVA Radial Flux Labs 16kWmotor/ 16kW generator generator 177 kgs 17 kgs Standard Industry VIEW IN CROSS-SECTION manufacturing techniques 6
Design Process - Electrical FEA –Maxwell and ANSYSThis analysis optimised the concept design of the 20kwgenerator to deliver high levels of flux density across the airgap between the rotor and the stators, while maintaininggood levels of flux consistency. 7
Design Process - Mechanical FEA - Deformation Analysis undertaken on the concept design to determinethepossible levels of deformation displayed by the generatordue to the magnetic and mechanical forces 8
Design Process - Mechanical FEA – HeatRFL’s design allows the dual stators to be mounted directlyon the casing plate facilitating a high level of heat transferfrom the stator to the casing. 9
Design Process - Manufacturing Efficiency Stators• Stator Laminations are designed to “nest” to facilitate use of centre material normally scrapped in conventional designs 10
Testing –Small Wind 20 kw TurbineTesting was on a platform designed to the Garrad Hassan (UK)specification as used for the independent testing of the 3 kwmicro wind generator 11
Traditional Permanent Magnet Design compared to RFL Dual Stator Single stator GinlongRotor Dual stator RFL
Cost/Nm$25.0 Energy Density$20.0$15.0 Due to it’s high output$10.0 and compact design RFL motors/generators are: $5.0 $0.0 • 90% cheaper per nm than PERM-MOTOR PMS DC Brush ( Leroy AC induction (WEG 8 PMG Inside Rotor PMG Outside Rotor RFL (211 Rpm ) 156 Somer LSK2504CL 260 Rpm) Pole KTE168 740 Rpm) (Ginlong 20 Kw 180 Rpm ) (CSIRO 20 Kw Westwind 211 Rpm) current DC brushed motors Kg/Nm • 45% cheaper per nm than current AC induction 0.90 motors 0.80 0.70 • Up to 87% lighter for the 0.60 same amount of torque 0.50 0.40 • Have up to 2.5x the energy 0.30 density 0.20 0.10 • Over 90% efficiency at 90% 0.00 of operating speed range PERM-MOTOR DC Brush ( Leroy AC induction (WEG PMG Inside Rotor PMG Outside Rotor RFL (211 Rpm ) 13 PMS 156 Somer LSK2504CL 8 Pole KTE168 740 (Ginlong 20 Kw 180 (CSIRO 20 Kw 260 Rpm) Rpm) Rpm ) Westwind 211 Rpm)
Toyota Prius Gen ll vs RFL Dual Stator Toyota Prius Gen II RFLMax Torque 339 Nm @ 250 Amps 340 Nm @ 250 AmpsNominal Max Power 50 Kw @ 1200 Rpm 45 Kw @ 1500 RpmTested continuous 21 Kw @ 1200 Rpm 29 Kw @ 3000 RpmPowerStator resistance & 0.155 Ohms 8 Poles 16 0.095 Ohms 18 Poles 18Poles Magnets MagnetsStator Length 83.56 mm 50 mmStator OD 270.0 mm 230 mmActive Material 79.5 Lbs( 36 Kg) 22.49 Lbs (10.2 Kg)weightCooling Liquid LiquidSOURCE• US Department of Energy reports into the Prius motor undertaken by the Oak Ridge National Laboratory. (Report references: ORNL/TM2004-185 , ORNL/TM-2004-247, ORNL/TM-2005/33, ORNL/TM-2004/137 ).
KEY DESIGN FEATURES OF RFL VS PRIUS•The RFL base design is of a comparable torque and utilizesless than a third of the active material that the Prius•Scaling the RFL design to the same size as that used in thePrius increases the power output to 104.5 Kw and a maxtorque of 783 Nm compared to the Prius at 50kw and a maxtorque of 339 Nm•This is powerful enough powerful enough to free the Priusfrom the real-time assistance of a combustion engine .•This is possible due to its exceptional torque, high overloadstart up and a lightweight and compact design.
ACTIVE MATERIAL COMPARISON PRIUS VS RFLTo achieve its rated levels of output the Prius design hasused significant amounts of copper and other activematerialsRFL design makes much more effective use of a smalleramount of material resulting in a staggering reduction ofactive materials of over 70%. as can be seen in followingphotographs
OVERLOAD COMPARISON PRIUS VS RFLThe critical issue of starting torque at take off point is afunction of the overload capacity of the motor design. TheWaveform comparison below illustrates the exceptionalperformance of the RFL design Phase A-B Phase A
OPTIMIZED MOTOR AND CONTROLLER DESIGN FOR ELECTRIC VEHICLES1. High Electrical Efficiency across the desired rev rangewhich determines the distance travelled on a given charge.2. High starting torque ensures the start up accelerationcapability and hill start and climbing capability will giveuseful real world performance with passengers3. High Energy Density enables a smaller and lighter wheelhub motor design influencing weight and bike styling4. High Regeneration energy recovery for battery rechargeunder braking deceleration provides the boost to battery lifefor useful travel distance, particularly in daily city commutertraffic
MOTOR DESIGN CHARACTERISTICS• embedded permanent magnets have their magneticorientation tangential to the flux in the stator windings•high saliency in the rotor•high reluctance torque•phase advance•field weakening•no demagnetization under high current loads•lower running frequency from the lower pole numbergiving lower stator core losses.
RELUCTANCE TORQUE AND FIELD WEAKENING Efficiency against Output Power 1 0.9 0.8 0.7 0.6 RFL Eff Efficiency Kelly Eff 0.5 Field weekning RFL 0.4 0.3 0.2 0.1 0 0 1000 2000 3000 4000 5000 6000 7000 8000 Output Poweri
FIELD WEAKENING Torque for Surface mount PM Motor using Field Weakening Control 60 50 Rated Speed 40 Torque 30 Constant Torque 20 region 10 Field Weakening Region Constant Power for Surface Magnet Rotor 0 0 2000 4000 6000 8000 10000 12000 SpeedField weakening is a motor control technique that allows a motor to runfaster than its rated speed
FIELD WEAKENING Torque for Embedded Magnet PM Motor using Field Weakening Control 100 Phase advance region 60 Rated Speed 50 40 Torque 30 Constant Field Weakening Region Constant Torque Torque for Embedded Magnet Rotori 20 region 10 0 0 2000 4000 6000 8000 10000 12000 Speed
The RFL Business PlanWe offer manufacturers a compelling proposition: use our designs todramatically reduce costs ,improve efficiency and performance 23