|Prototype of a Bladon Micro-Jet engine. Click to enlarge.
A consortium led by micro gas turbine company Bladon Jets recently secured investment from the UK Technology Strategy Board to develop an Ultra Lightweight Range Extender (ULRE) for next-generation electric vehicles. Total project cost is £2,206,784, with the TSB providing £1,103,392 (US$1.8 million). (Earlier post.)
The objective of the consortium, which includes luxury car maker Jaguar Land Rover and leading electrical machine company SR Drives (earlier post), is to produce the first commercially viable gas turbine generator designed specifically for automotive applications. Jaguar Land Rover is now part of Tata Motors.
The ULRE will incorporate a Bladon Jets patented, axial flow gas turbine engine coupled to a high-speed generator utilizing SR Drives’ proprietary switched reluctance technology. Design of the ULRE’s packaging for vehicle integration will be overseen by Jaguar Land Rover, which has earlier organizational experience with automotive turbines; Rover produced a series of gas turbine cars in the 1950s and ‘60s.
Bladon Micro-Jet Engines are 100% axial-flow, gas turbine engines for use in a variety of applications. Key features include:
- High efficiency multistage axial-flow compressor
- Clean burn annular combustion chamber
- High temperature axial flow turbine
- Oil-less carbon-air bearing system
- One moving part
Bladon suggests that in an hybrid vehicle application, with no water-cooling system, oil or catalytic converter, the Micro-Jet engine can provide vehicle weight savings of up to 15%—with a consequent reduction in fuel consumption and carbon emissions—compared to a piston engine. Further environmental benefits will be gained from its fast warm up (a few seconds, as opposed to several minutes for a conventional engine), cleaner combustion and lower manufacturing energy requirements, the company says.
One prototype—the BJ-300-P—weighs 4 lbs, is 4 inches in diameter by 12 inches in length, and delivers 27 lbf (120 N) of thrust. With a speed of 90,000 rpm, the prototype features a 5-stage axial flow compressor and a 1-stage axial flow turbine.
Bladon Jets’ patented manufacturing process enables the production of axial-flow compressors and turbines in smaller sizes than has previously been possible and can be used to bring about improvements in performance, efficiency and reliability of any size of gas-turbine engine or turbo-molecular pump, according to the company. In addition, the process significantly reduces the development time and manufacturing costs for new engines.
One piece integrally-bladed turbine components can be manufactured in virtually any profile, with varying section, edge radii and taper from root to tip and from any metal/alloy (including: aluminium alloys, nickel alloys, stainless steel and aerospace grades of titanium). Improved performance and efficiency is achieved by closer tolerances and reduced hub to tip ratios. Improved reliability is due to stress free machining from solid material and reduced inertial mass.
The basic switched reluctance SR Drive system comprises a simple brushless motor with a dedicated electronic controller. Torque is produced by the magnetic attraction of a steel rotor to stator electromagnets. No permanent magnets are needed, and the rotor carries no “squirrel cage” or windings. Properly designed and controlled, the SR motor can yield high efficiency across a very wide range of load conditions,
The SR Drives Group, which participated in the TIGERS project (earlier post), is based on a single site in Harrogate UK and comprises two operating companies: Switched Reluctance Drives Ltd (SRDL), and SR Drives Manufacturing Ltd (SRDML). Both companies are wholly owned subsidiaries of Emerson Electric Co of St Louis, Missouri—the world’s largest manufacturer of electric motors.
SR Drive has engaged in several hybrid drive projects in the past, including a collaboration with Green Propulsion, a Belgian company, to develop two switched reluctance motor-generators for a hybrid power-train project designed to cut carbon emissions in vehicles such as buses and waste collection vehicles.
Backing for the project was secured in a £15-million funding competition organized by the Technology Strategy Board to support the advancement of the mass adoption of low carbon vehicles and is a key part of its wider program to stimulate technology-enabled innovation and to help boost UK growth and productivity.
ETV Motors. In mid-2009, Israeli startup ETV Motors Ltd. (ETVM) completed a proof-of-concept test of its Range-Extended Electric Vehicle (REEV) architecture using a gas microturbine for the range-extending generator. The company had closed a $12M Series A round in April 2009. (Earlier post.)