Non-Rotary-Wing Aircraft Propulsion System with Direct AC Wingtip Drive
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Non-rotary-wing aircraft using electric or hybrid propulsion systems still emit significant polluting gases during take-off, landing, and taxi phases due to the operation of turbines for power supply, and existing systems incur substantial fuel consumption and drag from wingtip propulsion units.
Innovation Solution
A propulsion system for non-rotary-wing aircraft featuring an alternating-current generator connected directly to wingtip propulsion units without intermediate conversion, and a power supply circuit with an intermediate DC distribution stage and converters to power lift-increase propulsion units from batteries during take-off, reducing emissions and fuel consumption by minimizing electrical losses and optimizing wingtip drag.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the turbine operates during take-off, landing and taxi phases to power the propulsion units, then the thrust required for flight is provided, but polluting gas emissions increase significantly
Solution Approach 1:
The propulsion system is divided into two independent power supply circuits: a first circuit for wingtip propulsion units and a second circuit for lift-increase propulsion units. The second circuit includes an intermediate DC distribution stage with batteries that can operate independently during take-off and landing phases, allowing the turbine to be shut down or reduced to electric-only operation during these phases, thereby reducing emissions while maintaining thrust capability.
Solution Approach 2:
An intermediate DC distribution stage with batteries is introduced as an intermediary energy storage system between the generator and the lift-increase propulsion units. This intermediary allows the system to store electrical energy during cruising phases and discharge it during take-off and landing phases when the turbine is not operating, enabling emission-free propulsion during critical phases.
2Loss of energy
If wingtip propulsion units are used to reduce wingtip drag, then aerodynamic efficiency improves, but the complexity of the power supply circuit increases due to intermediate conversion stages
Solution Approach 1:
The power supply circuit is segmented into two independent paths: the first power supply circuit connects the generator directly to the wingtip propulsion units without intermediate conversion, while the second power supply circuit includes an intermediate DC distribution stage for lift-increase propulsion units. This segmentation allows the wingtip propulsion units to operate with minimal complexity and direct power supply, maintaining aerodynamic efficiency while reducing overall system complexity.
Solution Approach 2:
The intermediate conversion stages are extracted or removed from the first power supply circuit that powers the wingtip propulsion units. By taking out the AC/DC and DC/AC converters from this circuit, the system eliminates unnecessary complexity and electrical losses, allowing the wingtip propulsion units to be powered directly from the generator through a simple AC distribution stage.
3Power
If the turbine operates continuously to power propulsion units, then thrust is maintained, but fuel consumption increases
Solution Approach 1:
The system switches between different power sources periodically based on flight phases: during cruising phases, the turbine operates to charge the batteries and power the propulsion units; during take-off and landing phases, the batteries discharge to power the propulsion units while the turbine is shut down or reduced. This periodic switching optimizes fuel consumption by utilizing the energy stored in batteries during phases when the turbine is not operating at full power.
Solution Approach 2:
The system recovers and stores electrical energy in the batteries during cruising phases when the turbine is operating efficiently, and then discards (uses) this stored energy during take-off and landing phases when the turbine would otherwise need to operate at high power. This energy recovery and utilization strategy reduces overall fuel consumption by capturing excess energy during efficient operating conditions and using it during high-demand phases.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration significantly reduces polluting gas emissions near airports, enhances agility with flexible lift adjustment, and minimizes fuel consumption by eliminating AC/DC conversion losses during cruising phases, while maintaining efficient operation of wingtip propulsion units.
Implementation Method 1
an alternating-current generator (34), at least one wingtip propulsion unit (32) comprising an alternating-current motor
Implementation Method 2
an AC/DC converter, that electrically connects the generator to said intermediate DC distribution stage
Implementation Method 3
a DC/AC converter, that electrically connects said intermediate stage to the lift-increase propulsion unit
Implementation Method 4
one or more electric batteries (362) connected to said intermediate DC distribution stage
Implementation Method 5
a propeller (320) of this propulsion unit
Data Source
AI summary
The invention relates to a propulsion system (20) for a non-rotary-wing aircraft (3), the system comprising an alternating-current generator (24), at least one wingtip propulsion unit (22) comprising an alternating-current motor, and at least one lift-increase propulsion unit (23a-23d) comprising an alternating-current motor. The generator is connected to the lift-increase propulsion unit via a AC/DC converter (261), an intermediate DC distribution stage (260) provided with electric batteries (262) and a DC/AC converter (263a-263d). On the other hand, the generator is connected to the wingtip propulsion unit in such a way as to supply this propulsion unit with alternating current, without intermediate conversion of this alternating current into direct current.The invention also relates to an aircraft provided with such a propulsion system.