Multi-phase EAP Energy Harvesting System with Shared Power Electronics
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Multi-phase EAP energy conversion systems face challenges with high peak-to-average power ratings and low electromechanical conversion efficiency due to the need for cyclic bias energy, which increases the power rating and cost of Power Electronic Units (PEUs) and limits control over individual EAP sections, especially in applications with irregular excitation sources.
Innovation Solution
A multi-phase EAP energy harvesting system with a plurality of EAP sections connected in series to a common power source/sink unit, utilizing electronic charge/discharge units and a controller to manage energy exchange and control signals, allowing for independent control of each EAP device and optimizing energy harvesting cycles to reduce the active power processing requirement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a dedicated Power Electronic Unit (PEU) is used for each EAP device in single-phase systems, then full controllability on the harvesting cycle is achieved, but the peak-to-average power rating becomes high resulting in high converter cost and low electromechanical conversion efficiency
Solution Approach 1:
The patent combines multiple EAP devices into a multi-phase system where they share a common Power Electronic Unit. The EAP devices are operated in parallel phases, allowing the PEU to serve multiple devices simultaneously rather than requiring dedicated PEUs for each device, thereby reducing the peak-to-average power rating and converter cost while maintaining control capability.
Solution Approach 2:
The patent employs periodic operation of EAP devices in different phases, where devices are activated in sequence rather than simultaneously. This periodic activation pattern allows the Power Electronic Unit to handle lower peak power demands by distributing the load across time, reducing the required power rating while maintaining full controllability through phased harvesting cycles.
2Loss of energy
If cyclic bias energy is applied to EAP devices, then electromechanical conversion is enabled, but the power rating of Power Electronic Units increases and converter efficiency decreases
Solution Approach 1:
By merging multiple EAP devices into a multi-phase system with a shared Power Electronic Unit, the patent reduces the overall power rating requirement. The cyclic bias energy is distributed across multiple devices operating in parallel, allowing the common PEU to operate at lower peak power levels while maintaining the necessary electromechanical conversion efficiency through coordinated control of the harvesting cycles.
3Power
If multiple EAP devices are used in multi-phase systems, then power capacity requirements are reduced and efficiency is improved, but individual control of EAP sections becomes limited
Solution Approach 1:
The patent implements dynamic control of EAP devices in multi-phase systems by enabling individual harvesting cycle control for each device while sharing a common Power Electronic Unit. The system dynamically adjusts the operation of each EAP device based on its specific conditions and phase, allowing individual control capability to be maintained even though multiple devices share the same PEU infrastructure.
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 reduces the power rating and cost of PEUs by 30 times, decreases converter efficiency constraints, and simplifies power electronics, while also reducing cable length and power fluctuations, enhancing grid stability and reliability.
Implementation Method 1
the variable capacitor comprising an elastically deformable body with an arrangement of stretchable synthetic material and electrodes being arranged as the variable capacitor with a capacitance that varies as the deformable body stretches and relaxes
Implementation Method 2
EAP (Electro Active Polymers) based actuators and generators
Data Source
AI summary
Method including a plurality of EAP based sections, a power source/sink unit and a controller. Each EAP based section includes an electronic charge/discharge unit and variable capacitor having an elastically deformable body with an arrangement of stretchable synthetic material and electrodes functioning as the capacitor with a variable capacitance as the deformable body stretches and relaxes. Each EAP based section is connected to the power source/sink unit by the respective electronic charge/discharge unit under control of the controller which includes: a processing unit coupled to a sensing circuitry which is coupled to the variable capacitor of each EAP based section, and a driving circuitry coupled to the electronic charge/discharge unit. The method includes for each EAP based section: receiving a state parameter signal/signals from the capacitor; establishing a dedicated control signal based on the associated state parameter signal/signals received; transmitting the dedicated control signal to the associated electronic charge/discharge unit.