Electrochromic Device Control via Pulsed Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrochromic devices face a trade-off between rapid switching and degradation, as high voltages required for fast switching can lead to irreversible oxidative or reductive degradation, limiting their operational lifespan and efficiency.
Innovation Solution
The method involves applying a pulsed continuous voltage with a controller-connected power source, using a photosensor to measure potential and determine overpotentials, applying a decreasing sequence of overpotential pulses, and maintaining an operating potential within safe limits to achieve rapid switching without degrading the device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If high voltage is applied to achieve fast switching, then switching speed is improved, but device degradation occurs due to overpotential
Solution Approach 1:
The patent applies periodic voltage pulses instead of continuous high voltage. The controller delivers a series of voltage pulses with specific duration and frequency to achieve the desired transmittance change while allowing the device to partially relax between pulses, preventing cumulative degradation from sustained overpotential
Solution Approach 2:
The patent dynamically adjusts the voltage waveform based on real-time feedback from the photosensor. The controller modifies pulse amplitude, duration, and frequency to match the actual device state, enabling fast switching when needed while reducing voltage stress during steady-state operation to prevent degradation
2Reliability
If continuous monitoring and control are implemented, then device protection is improved, but system complexity increases
Solution Approach 1:
The patent implements a feedback control loop where the photosensor continuously monitors the actual transmittance of the electrochromic device and sends this information to the controller. The controller compares the measured transmittance with the target transmittance and adjusts the voltage pulses accordingly, providing automatic protection against overpotential while maintaining simple operation
Solution Approach 2:
The system uses the photosensor to automatically detect the device state and trigger appropriate control actions without user intervention. The controller self-regulates the voltage application based on real-time feedback, protecting the device from degradation while eliminating the need for complex external monitoring systems
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 electrochromic switching time by a factor of 10 or more without causing degradation, allowing for faster transitions between light and dark states while maintaining the device's integrity over numerous cycles.
Implementation Method 1
Certain electrochromic materials may change color when applying a voltage. The change in color of an electrochromic material is usually due to reduction/oxidation ('redox') processes within the electrochromic materials.
Implementation Method 2
The change in color of an electrochromic material is usually due to reduction/oxidation ('redox') processes within the electrochromic materials.
Implementation Method 3
measuring a potential at a photosensor operably connected to the controller
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention provides apparatuses and methods for modulating the transmissivity of electrochromic devices utilizing a controller that provides a continuous potential that may be pulsed to the electrochromic device.