Composite Ovoid Flywheel Structure for High-Speed Energy Storage
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Solution Overview
Problem
Current flywheel energy storage systems are limited by their structural design and material selection, leading to high costs and mass constraints, making them impractical for efficient energy storage due to the need for increased mass and complexity in subsystems, which raises operational and installation costs.
Innovation Solution
A high-speed, compact elliptical ovoid flywheel design utilizing helically wound resin-impregnated composite filament material with internal composite structures for compressive support, allowing for increased rotational speed and energy storage capacity while minimizing mass and subsystem complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If traditional mass-focused flywheel designs are used with steel or composite materials, then energy storage capacity increases linearly with mass, but system mass and subsystem complexity increase significantly
Solution Approach 1:
The patent changes the geometric parameters of the flywheel from traditional disk or ring-rim shapes to an elliptical ovoid shape with specific dimensional ratios (major axis to minor axis between 1.1:1 and 2.0:1). This shape optimization, combined with strategic placement of inertial mass at the periphery, increases energy storage capacity by a factor of five or more without proportionally increasing system mass or complexity
Solution Approach 2:
The patent employs an elliptical ovoid shape instead of traditional flat disk or cylindrical forms. This curved, three-dimensional geometry allows for more efficient mass distribution and higher moment of inertia per unit mass, achieving superior energy storage density while maintaining structural integrity without additional subsystem complexity
2Quantity of substance
If flywheel mass is increased to improve energy storage capacity, then energy storage increases linearly, but manufacturing, delivery, and emplacement become practically limited
Solution Approach 1:
By optimizing the geometric parameters to an elliptical ovoid shape with controlled aspect ratios and strategic mass distribution, the patent achieves higher energy storage in a more compact form factor. This reduces the absolute mass required for a given energy capacity, making manufacturing and installation practically feasible
Solution Approach 2:
The patent utilizes composite materials with high strength-to-density ratios to construct the elliptical ovoid flywheel. This allows for high moment of inertia and energy storage capacity without requiring proportionally high mass, thereby improving ease of manufacture and installation while maintaining structural integrity at high rotational speeds
3Quantity of substance
If higher rotational speeds are achieved through stronger materials, then energy storage improves by a power of two, but structural design and material selection become more challenging
Solution Approach 1:
The elliptical ovoid shape with its smooth curved surfaces and optimized dimensional ratios creates more favorable stress distributions during high-speed rotation compared to traditional flat disk designs. This geometric optimization reduces stress concentrations and allows for higher rotational speeds with simpler structural design
Solution Approach 2:
The patent optimizes geometric parameters including the major-to-minor axis ratio (1.1:1 to 2.0:1), shell thickness distribution, and mass placement to maximize moment of inertia while minimizing stress. These parameter optimizations enable higher rotational speeds without requiring overly complex structural designs or exotic materials
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
The elliptical ovoid flywheel design achieves up to five times higher energy storage capacity per unit mass and volume compared to traditional designs, with improved operational safety and reduced costs, enabling efficient energy storage and release for renewable and traditional power systems.
Implementation Method 1
Flywheels have been well established for over 2000 years as energy storage devices in the form of spinning kinetic energy
Implementation Method 2
The flywheel kinetic energy storage (Ek) capability is governed by the standard equation Ek = 1⁄2 I ω^2 where the structural design mass placement in the moment of inertia (I) and the flywheel rotational speed (ω) are the two energy storage drivers
Implementation Method 3
An example high speed, elliptical ovoid flywheel includes a composite shell formed of helically wound ribbons of resin-impregnated composite filament material combined with internal composite structures providing compressive support
Implementation Method 4
Vacuum enclosed flywheels coupled with ultra-low friction magnetic bearings are particularly well suited for ESS applications that require frequent charge/discharge cycles per day
Implementation Method 5
Vacuum enclosed flywheels coupled with ultra-low friction magnetic bearings
Data Source
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AI summary
An example flywheel energy storage device includes a continuously curved fiber-resin composite ovoid shell. Hubs are concentrically disposed within and outside the shell at the shaft. A plurality of radially oriented, fiber-resin composite helical wraps of uniform width are used to construct the ovoid shell and couple the shell to the hubs for co-rotation and torque transfer. Integrated internal structures are attached to the external ovoid shell and provide compression support for the external ovoid shell. Upon rotation, the ovoid shell elongates slightly to increase the flywheel effective moment of inertia at operational speeds.