Multi-Stack Flywheel Energy Storage with Universal Joint
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Solution Overview
Problem
Existing flywheel energy storage systems require significant time and power to charge and recharge, and partially charged flywheels can cause drag when discharged, leading to inefficiencies due to their heavy weight and reliance on a single, heavy flywheel.
Innovation Solution
A multi-stack flywheel energy storage assembly with multiple lighter flywheels that power up sequentially using speed-activated clutches and roller stops, allowing only charged flywheels to engage the drive shaft during discharge, reducing power input and charge time, and incorporating a universal joint to mitigate gyroscopic precession.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a single heavy flywheel is used to store energy, then energy storage capacity is improved, but charge time and power input increase significantly
Solution Approach 1:
The patent divides the single heavy flywheel into multiple lighter flywheels (first flywheel, second flywheel, third flywheel, etc.) that can be charged sequentially. This segmentation allows the system to achieve the same total energy storage capacity while reducing the time and power required to charge each individual flywheel, as they can be brought up to speed in sequence rather than simultaneously
2Quantity of substance
If a single heavy flywheel is used, then energy storage capacity is improved, but the system requires significant power input to operate
Solution Approach 1:
By segmenting the flywheel system into multiple lighter units, the patent reduces the instantaneous power input required. Each flywheel requires less power to accelerate to operating speed compared to a single heavy flywheel, and the sequential charging approach allows the motor/generator to operate at lower power levels while still achieving the same total energy storage capacity
3Power
If a heavy flywheel is discharged before reaching optimum speed, then power delivery is improved, but energy storage efficiency decreases
Solution Approach 1:
The patent creates a pool of multiple flywheels that can be charged to full capacity before discharge. During discharge, the system can draw from multiple fully-charged flywheels simultaneously, providing the necessary power delivery while maintaining high energy storage efficiency. The sequential engagement mechanisms ensure that only fully-charged flywheels are connected to the drive shaft during discharge operations
4Loss of time
If multiple flywheels are used to reduce charge time, then charge speed is improved, but device complexity increases
Solution Approach 1:
The patent divides the flywheel system into multiple modular units, each with its own engagement mechanism. This segmentation enables parallel or sequential charging operations that reduce overall charge time while keeping each individual module relatively simple in design
Solution Approach 2:
The patent employs dynamic engagement mechanisms including speed-activated clutches and roller stops that automatically connect or disconnect flywheels based on their rotational speed and charge state. These dynamic mechanisms reduce the need for complex manual control systems, as the flywheels self-regulate their engagement with the drive shaft based on operational parameters
5Productivity
If speed-activated clutches and roller stops are used for sequential engagement, then charge efficiency is improved, but device complexity increases
Solution Approach 1:
The speed-activated clutches and roller stops are designed to automatically engage and disengage based on the rotational speed and charge state of each flywheel, without requiring external control signals or complex monitoring systems. This self-service capability improves charge efficiency while minimizing the added complexity, as the mechanisms use the system's own operational parameters to control engagement
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 multi-stack design reduces power input, shortens charge time, eliminates drag from uncharged flywheels during discharge, and increases energy storage capacity by utilizing smaller motors and spreading torque and weight across multiple bearings, enhancing efficiency and reliability.
Implementation Method 1
a suspended flywheel assembly having a universal joint to help reduce effects of gyroscopic precession
Implementation Method 2
Electricity is stored as kinetic energy in the rotating flywheel
Implementation Method 3
utilizes magnetic bearing and computer stabilization
Data Source
AI summary
A flywheel based energy storage system which can include one or more flywheels and a motor/generator unit is disclosed. The system can include a universal joint connecting a suspended flywheel and motor/generator to another body (e.g., frame or mounting point on another structure). The universal joint permits automatic adjustment of an axis of the suspended flywheel to help reduce effects of gyroscopic precession on the flywheel system. A single flywheel is fixed to the drive shaft. Multiple additional flywheels are mounted to drive shaft via bearings to allow freewheeling. The fixed (or first) flywheel is fully charged before speed activated clutch engages second flywheel. All additional flywheels are started sequentially in like manner. During discharge, charged flywheels engage drive shaft via one-way ratchet type mechanism and non-charged flywheels continue to freewheel. A sectional drive shaft of one embodiment simplifies portability and assembly. A variable inertia flywheel of another embodiment further reduces charge-up time.