The tests are part of one of the world’s most comprehensive hybrid aerospace turbine engine development and integration programmes and pave the way for experimental flights on aircraft in 2021.
The company successfully tested the hybrid version of the M250 gas turbine in a ground demonstration setting in three operating modes: Series Hybrid, Parallel Hybrid and Turbo-Electric.
The M250 hybrid is planned to be used as a propulsion plant with power ranging from 500kW to 1MW and has the potential to transform aviation power. The system will be used across a range of transport platforms to enable distributed electric propulsion, including EVTOLs (hybrid electric vertical take-off and landing vehicles), general aviation aircraft and hybrid helicopters.
Dr Mike Mekhiche, deputy director, Rolls-Royce Electrical said: “Rolls-Royce has always been a pioneer in aviation and one of the key elements of our strategy is to champion electrification across all our businesses. The successful testing of the hybrid M250 system is an important step forward in providing a hybrid-electric propulsion system that will enable a new class of quieter and cleaner air transport.”
Rolls-Royce engineers based in the United States, UK and Singapore have developed this engine into a hybrid-electric propulsion system. The M250 gas turbine engine has powered more than 170 varieties of fixed-wing military, civilian aircraft and helicopters since its initial development. Rolls-Royce selected this engine for its maturity, power-density, ease of maintenance, and high reliability. In the past half-century, M250 variants have logged more than 250 million flight hours and nearly 33,000 M250 engines have been delivered to customers.
Complete engine testing took place at Rolls-Royce’s facility in Indianapolis where each component and sub-system of the hybrid engine was individually tested for electrical performance. These tests included simulating use across take-off, cruise, landing and taxiing and confirmed the system’s suitability for a range of transport platforms including aircraft with a range of up to 1000 miles and weighing up to 2,000kg. This would support the Rolls-Royce EVTOL concept which was unveiled during the Farnborough Air Show in the UK last year as well as meeting many other customers’ requirements.
The Rolls-Royce hybrid electric propulsion system demonstrator integrates a M250 gas turbine engine with a high energy density battery system, electric generators, power converters and an advanced power management and control system. The power management system optimises overall propulsion performance in order for the system to be suitable across a variety of platforms, including EVTOL, while delivering efficiency gains, reduced noise and lower emissions.
Tests were successfully carried across three system configurations:
