Hybrid Engine Power Control for Rotorcraft Efficiency

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Solution Overview

Problem

Rotary wing aircraft face inefficiencies in energy use due to the need to distribute power equally among multiple heat engines, leading to operating ranges that are not optimized for energy efficiency, which can reduce flight duration and distance.

Innovation Solution

A method involving a processing unit that evaluates conditions to put one heat engine to rest and accelerate the others, with the assistance of an electric unit to maintain optimal power levels, allowing for optimized energy efficiency by operating heat engines at their most favorable performance points.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If power is distributed equally among multiple heat engines, then reliability and safety are improved, but energy efficiency deteriorates

Engineering Contradiction:
Improveflight safetyVSAvoidenergy efficiency
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies asymmetry by allowing unequal power distribution among heat engines. Instead of requiring equal power sharing for safety, the system permits asymmetric operation where one engine can be idled while another provides all necessary power, combined with asymmetric energy storage architecture using capacitors and batteries to balance power delivery requirements.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The patent introduces energy storage devices (capacitors and batteries) as intermediaries between the heat engines and the power transmission system. These intermediaries buffer power fluctuations, enabling one engine to be idled while the other compensates, thus mediating between the conflicting requirements of unequal engine operation and stable power supply.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If heat engines operate at moderate power levels to meet flight requirements, then adaptability is improved, but energy efficiency deteriorates

Engineering Contradiction:
Improveflight envelope flexibilityVSAvoidspecific consumption
Core Design Contradiction:
Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent applies dynamics by enabling real-time switching between different engine configurations. The system can dynamically transition between one-engine and two-engine operation modes, and between idle and active states, allowing heat engines to operate at optimal power levels (including high-efficiency moderate power or maximum power when needed) rather than fixed moderate power, thus maintaining adaptability while improving efficiency.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the operating parameters of heat engines by allowing them to operate at different power levels including idle state, moderate power for efficiency, and maximum power for performance. The system modifies engine operational parameters dynamically based on flight conditions, energy storage state, and efficiency requirements, rather than maintaining fixed parameter settings.

Inventive Principle:
Principle #35Parameter changes

3Use of energy by moving object

If one heat engine is idled to improve energy efficiency, then fuel consumption is reduced, but reliability deteriorates

Engineering Contradiction:
Improvefuel consumptionVSAvoidflight safety
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The patent applies beforehand cushioning by pre-charging energy storage devices (capacitors and batteries) before single-engine operation. This prior energy buffering cushions the system against potential engine failures, allowing one engine to be idled for efficiency while the energy storage system provides a safety margin that compensates for reduced redundancy.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The energy storage devices serve as intermediaries that decouple the reliability function from the efficiency function. They mediate between the reduced redundancy of single-engine operation and the safety requirements, providing power buffering and transient support that maintains reliability standards even when one engine is idled for fuel efficiency.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Reliability

If heat engines operate continuously to maintain safety redundancy, then reliability is improved, but duration of action deteriorates

Engineering Contradiction:
Improveengine redundancyVSAvoidflight duration
Core Design Contradiction:
ReliabilityVSDuration of action of moving object

Solution Approach 1:

The patent extracts the redundancy function from continuous engine operation. Instead of requiring both engines to run continuously for safety, the system extracts the essential redundancy benefit through energy storage devices that provide power buffering and transient support, allowing one engine to be idled while maintaining effective redundancy through the stored energy capability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The energy storage system provides self-service by automatically managing power delivery and engine control to optimize the balance between redundancy and fuel consumption. The system autonomously determines when to idle engines and when to activate them, using the stored energy to maintain safety standards without requiring continuous operation of all engines, thus extending flight duration.

Inventive Principle:
Principle #25Self-service

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 approach improves overall power transmission efficiency, enabling the aircraft to maintain or exceed optimal energy performance speeds while reducing fuel consumption and increasing flight duration and distance.

Implementation Method 1

at least one electric motor which can operate in an electric motor mode and in an electric generator mode

Methodology Applied
Scientific EffectElectromagnetic conversion: Electromagnetic Induction

Implementation Method 2

at least two heat engines

Methodology Applied
Scientific EffectThermal energy conversion: Heat Engine

Data Source

PatentEP2548803B1Method for controlling a group of engines and aircraft
Publication Date: 2015.08.05 EUROCOPTER FRANCE SA
  • EP2548803B1 patent drawingFigure 1~3
  • EP2548803B1 patent drawingFigure 4
  • EP2548803B1 patent drawingFigure 5

AI summary

The present invention relates to a method for controlling a group (2) of motors developing a required power (Wnec) to drive a rotor (3), said group (2) of motors being equipped with at least one electrical component (4), an electrical storage means (5), and a first number (n) of internal combustion engines (6) greater than or equal to two. A processing unit (10) executes instructions to evaluate a primary condition under which the group of motors can develop the required power by leaving one internal combustion engine at rest, and if necessary, to leave one internal combustion engine at rest and accelerate a second number of internal combustion engines not at rest, and to operate the electrical component in motor mode if necessary, the electrical component operating temporarily in generator mode when the storage means is discharged.