Presentation on theme: "Radial Flux Technology (RFT) Generator Design and Development History 3 kW GMI GENERATOR."— Presentation transcript:
Radial Flux Technology (RFT) Generator Design and Development History 3 kW GMI GENERATOR
GMI Technology Background Global Motors Invent Pty Ltd was established in 1995 to design and commercialize a new technology for electric motors and generators with higher efficiency, lower weight and more compact dimensions than any other available in the world. The 2 technologies developed were the T Flux based on ultra low weight with no steel content in the design and Radial Flux Dual Stator using more conventional manufacturing methods and materials. The design basis of this technology objective was a radical approach to magnet and winding configuration which led first to the design of the T Flux Technology (U.S Patent 5798591 1998)
T Flux Technology The T-Flux motor design achieved a 10% gain in electrical efficiency while reducing weight and materials by 85%. The dramatic size reduction of the model T-Flux 406 against a typical 4 kW 3phase motor can be seen below. The Radical design pushed all the relevant technologies for motors and generators to the limit: it has no steel at all. The uniquely configured windings were held with a custom designed plastic shell containing the permanent magnet ring and windings. This is illustrated below
This concept was executed in a number of prototypes, one of which is shown in the following photographs where the section has been halved A second smaller model was produced as is seen to the right. The larger (cut open) model produced 8 kW and the smaller model 4 kW
A less serious but functional application was a powered bicycle Trial applications included a water pump to illustrate the significant size reduction for comparable output
This technology breakthrough become the design basis for a range of motors used in Solar Racing Car and Boat design from 1995 to 2000, winning 43 awards in this period. After these trial products the chosen production versions were focused exclusively on the supply of motors to the Solar Race car industry where the extreme weight reduction and performance gains were of greatest value. The Shell ® car here incorporated T Flux motors
Comparison of T-Flux 406 Motor and Typical 5 hp, 3,000 rpm, 3 Ph Motor T-Flux 5 hpComment re T-Flux Input @ Full Load 4.025 kW 4.8 kW almost 800 W less input Output @ Full Load 3.686 kW 4.0 kW Full Load Speed 2,651 rpm 2.892 rpm Full Load Torque 13.77 nm 13.00 nm Full Load Efficiency 91.58% 83.33% 8.24% higher efficiency 50% F.L. Efficiency 94.4% 81.0% 13.4% “ at lower load Power Factor Full Load 99.0% 85.0% 14.0% higher pwr factor Power Factor 50% F.L. 99.0% 76.0% 23.0% “ at lower load Weight 7.5 kg 47 kgonly 1/7 th the weight Start Torque 230 nm 33 nmnearly 7x the torque Torque at 35 KVA 110 nm 42 nmnearly 3x the torque KVA at 42nm 12.9 kVA 35 kVA 64% less power needed Motor Outside Diameter 200 mm 240 mm 1/6 th smaller diameter Motor Length 100 mm 300 mm 2/3rds shorter Volume of motor 3,145 cc 13,586 cc75% size reduction The T-Flux has a linear torque speed relationship and speed voltage relationship giving improvements to ease of control. It can be wound to run at any speed and robust rotor construction enabling speed to 10,000 rpm
Radial Flux Dual Stator Technology The T-Flux design was so afar ahead of its time in features such as all plastic components, zero steel content and resulting potential for some electromagnetic interference with electronic devices in close proximity that funds for further development and commercialization were not readily available despite its success in the solar car and boat applications. The specialized tooling required for the winding and injection molding process was a further restraining factor for investors.
As a result the inventor of the T-Flux and driver of the GMI Technology, Paul Lillington, developed an entirely new approach to achieve many of the efficiency, size and weight advantages of the T-Flux design without any of its possible application constraints. The new design is based on the same radical rethinking of the magnet and winding configurations possible except this time with conventionally available materials and manufacturing technology. (Radial Flux PCT Patent 2008903100) Radial Flux Dual Stator Technology
It is, simply expressed, a generator within a generator, giving in one compact configuration the output of 2 generators. This was achieved through a rigorous conformance to 3 design rules: Minimum iron Minimum magnet material Maximum active copper Radial Flux The Radial Flux Concept
Conclusion The radial flux concept is based on successful technology with a proven track record, and the prototypes are being custom designed to meet the unique challenges of a wind turbine.