Rapid Sweeping Load Testing Circuit for Photovoltaic Cells
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for testing photovoltaic cells under pulsed conditions are unable to rapidly sweep the load voltage within the required time frames, making it difficult to incorporate into large-scale manufacturing facilities efficiently and inexpensively.
Innovation Solution
A circuit utilizing high-speed switches and capacitors to achieve a rapid voltage sweep across photovoltaic cells, allowing for measurements during a time frame of 10 microseconds to 10 milliseconds, with the ability to connect and disconnect load capacitors to charged capacitors to apply a pulsed light source and obtain voltage and current measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If known testing systems are used, then the testing process is simple and inexpensive, but the load sweeping speed is too slow to meet high-speed timing requirements
Solution Approach 1:
The testing circuit is segmented into multiple independent capacitor banks (first capacitor, second capacitor, third capacitor with different capacitances) that can be selectively connected through switches. This segmentation allows rapid switching between different capacitance values to achieve fast load sweeping while keeping each individual capacitor simple and inexpensive.
Solution Approach 2:
The circuit employs dynamic switching mechanisms where solid-state switches rapidly connect and disconnect capacitors based on testing requirements. This dynamic reconfiguration enables the load capacitance to change from microfarad range to nanofarad range within microseconds, achieving the required high sweeping speed without permanent complex circuitry.
2Productivity
If the load is swept rapidly within 10 microseconds to 10 milliseconds, then testing efficiency increases for manufacturing facilities, but the circuit complexity and cost increase
Solution Approach 1:
Capacitors are pre-charged to specific voltages before the actual measurement phase. The first and second capacitors are charged to different voltage levels, and through rapid switching, these pre-charged capacitors are connected to create the desired load profile. This preliminary charging action enables the rapid voltage sweep across the photovoltaic cell without requiring complex real-time voltage control during measurement.
Solution Approach 2:
The third capacitor with smaller capacitance acts as an intermediary element that facilitates rapid voltage transitions. By strategically connecting this smaller capacitor in parallel with the larger capacitors, the circuit achieves fast voltage changes needed for high-speed testing while the larger capacitors provide the necessary voltage levels.
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
Enables faster and more efficient testing of photovoltaic cells by providing a rapidly changing load, allowing for consistent quality control in manufacturing facilities, with the capability to sweep voltage across the cells within the desired time frames.
Implementation Method 1
a first capacitor coupled in a parallel configuration to the first power supply; a second capacitor coupled in a parallel configuration to the second power supply; third capacitor comprising a capacitance substantially smaller than each of the first and the second capacitors
Implementation Method 2
first and second switches respectively coupling the first and second capacitors to the third capacitor. In one embodiment, at least one of the switches is a solid state switch and more preferably, both of the switches are solid state switches
Implementation Method 3
a first current limiting component connecting the first power supply to the first capacitor; a second current limiting component connecting the second power supply to the second capacitor
Data Source
AI summary
A circuit and method that provides an inexpensive and easily implemented rapidly-changing load test circuit for photovoltaic cells, which can be under pulsed light conditions. Embodiments of the present invention permit the testing of photovoltaic cells by causing a sweeping voltage across the photovoltaic cell in a very short time period.