Variable Power Energy Harvesting System with Dynamic Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Energy harvesting systems from variable power sources, such as solar cells, face inefficiencies due to intermittent and variable energy output, leading to suboptimal performance during low and high power conditions, as they are typically designed for peak loads rather than fluctuating energy levels.
Innovation Solution
The development of variable power energy harvesting systems with dynamic control loops and configurations like boost, buck, and buck-boost, which include logic for adjusting power input and using comparators and sensors to regulate output, ensuring efficient energy harvesting across a wide range of power levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If systems are designed to operate at peak power levels, then they can handle maximum load requirements, but efficiency deteriorates during operation at lower intensity levels
Solution Approach 1:
The patent implements dynamic power management by switching between different circuit configurations (full bridge and half bridge) based on the instantaneous power level from the photovoltaic array. This allows the system to adapt its impedance matching to the variable power conditions, maximizing energy harvesting efficiency across the entire power range rather than being optimized only for peak conditions.
Solution Approach 2:
The system changes operational parameters (circuit topology, switching duty cycle, impedance levels) based on the power level detected from the energy source. By monitoring the power output and dynamically adjusting the circuit configuration, the system maintains optimal efficiency whether operating at peak power or low power levels, resolving the contradiction between peak power capability and low power efficiency.
2Device complexity
If switch mode power supplies operate with fixed duty cycle, then control is simplified, but power output varies with duty cycle changes affecting input voltage and power
Solution Approach 1:
The patent implements a feedback control mechanism that monitors the power output from the photovoltaic array and adjusts the switching duty cycle accordingly. This closed-loop control ensures that the system maintains optimal power transfer efficiency while adapting to varying environmental conditions, resolving the conflict between simplified fixed-duty-cycle control and stable power output.
3Reliability
If energy harvesting systems are designed for robust peak load operation, then they can handle maximum demands, but efficiency is compromised during lower intensity operation
Solution Approach 1:
The patent divides the power management system into multiple operational modes (full bridge mode for high power, half bridge mode for low power) that can be selectively activated. This segmentation allows each mode to be independently optimized for its specific power range, ensuring both reliability under peak loads and high efficiency during lower intensity operation, rather than using a single compromise design.
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
These systems improve energy harvesting efficiency and extend battery life by maximizing energy capture during low power conditions and handling high power inputs effectively, reducing costs and enhancing operating ranges.
Implementation Method 1
Solar power, for example, typically relies on solar cells, or photovoltaic (PV) cells, used to power electronic systems
Data Source
AI summary
The disclosed invention provides examples of preferred embodiments including systems for harvesting energy from variable output energy harvesting apparatus. The systems include energy harvesting apparatus for providing energy input to a switched mode power supply and a control loop for dynamically adjusting energy harvesting apparatus input to the switched mode power supply, whereby system output power is substantially optimized to the practical. Exemplary embodiments of the invention include systems for harvesting energy using solar cells in boost, buck, and buck-boost configurations.