June 2011

Control Techniques re-commission the Lotus experimental engine

Paul Stewart
Control Techniques engineer working on the AC drive unit

The rotary electrical drive on the Lotus free-piston experimental engine has now been re-commissioned by an engineer from Control Techniques.

The rig is now ready to be transported from the ThinkTank to its new home in an engine test cell in the new building.

The engine is part of a long-term R&D programme into new engine technologies and combustion control techniques led by Prof Paul Stewart, in collaboration with Lotus Engineering in Norwich.

The programme is looking at advanced drive trains for Hybrid Electric vehicles.

Lotus experimental engine, with Control Techniques drive cabinet open in the background

The CT drive supplies the Emerson 15kW Permanent Magnet AC Motor (PMAC) which is coupled to the crankshaft and acts as a motor-generator to control piston trajectory when the linear free piston engine is tethered to the crankshaft.

Recommissioning the Lotus Experimental Free-Piston Engine

Paul Stewart
Camshaft drive transfer box

Now that the Free-Piston engine is back at the ThinkTank, the electrical drive to the main crankshaft servo will be re-commissioned by Control Techniques Ltd.

The Engine has been away for a while having a new linear electrical motor-generator fitted, and is now ready for electrical re-comissioning before we move it into it’s test-cell in the new School of Engineering building.

The engine is unique, in that it allows piston trajectory control for experimentation on both conventional (with crankshaft) and free-piston (linear electrical machine, no crankshaft) operation.

After re-commissioning and installation in the new building, Prof Stewart will be continuing research into fundamental combustion, multi-fuel operation with variable compression ratios and free-piston operation in collaboration with Dr Jill Stewart, Reader in Thermofluids.

Free-Piston engine in the ThinkTank lab waiting for re-commissionng