With the completion of a rated power test of a 1MW electric motor-generator developed by its subsidiary Collins Aereospace, Raytheon Technologies’ ambitions to advance hybrid-electric flight have taken a significant step forward.
The motor will then be combined with a thermal engine from Pratt & Whitney Canada to form the core of a new hybrid-electric propulsion system. Next year, the system will be tested in flight on a modified De Havilland Canada Dash 8-100.
Collins claims that the new electric motor will have twice the voltage, four times the power, and half the heat loss and weight of its current highest-performing counterparts.
The motor is being developed at Collins’ facilities in Solihull, UK, and tested at the Institute for Aerospace Technology at the University of Nottingham.
Collins vice president of electric power systems Eric Cunningham claims that, despite the test motor’s 1MW capacity, its design is adaptable to a wide range of applications.
Scaling down is much simpler than scaling up: After you have demonstrated a 1MW motor, it is much easier to convince the world that you can make a 200kW motor.”
The motor has delivered the stated 1MW output in laboratory conditions when the rated power test is completed.
It was paired with the gas turbine engine in P&WC’s Longueuil, Quebec, facility in December of last year; however, the most recent test was “really an opportunity to put it back on the test stand and really push this thing to one megawatt.”
“We actually pushed it a little bit over, but we made sure we could hit those power levels, and we checked those,” the team said.
According to Collins senior technical fellow Todd Spierling, the tests went according to plan: It carried out the necessary actions and met expectations. Despite the fact that there were minor issues with the test gear that implied it was “not a stroll in the park”, he says, “we had the option to step our direction up and meet the numbers.”
Cunningham says the engine utilizes a spiral transition design, which was chosen due to the “speed ranges we are managing, as well as the power levels”.
One of the Dash 8-100’s two PW120 turboprop engines will be replaced by the propulsion system and batteries later, with flight testing expected to begin in 2024. However, P&WC has yet to provide specifics regarding the brand-new thermal engine.
The Canadian and Quebec governments are behind the project.