Solar Cell Testing Apparatus with Rotatable Filter Wheel

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current solar cell testing methods are inefficient and impractical for testing 100% of solar cells or concentrator solar modules, as they are typically performed on separate test stands at low power levels and lack the capability to detect defects and measure performance effectively.

Innovation Solution

A solar cell testing apparatus that includes an illuminator and a device with a rotatable filter wheel and motor for selectively positioning filters in the optical path, allowing for precise measurement of performance and defect detection by passing different percentages of light intensity and spectrums, along with a beam splitter for directing light to measure characteristics and perform electroluminescence tests.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If solar cell testing is performed using existing separate test stands at low power levels, then the testing can be conducted with simple equipment, but the testing efficiency is low and it is impractical to test 100% of solar cells

Engineering Contradiction:
Improvetesting efficiencyVSAvoidapparatus complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent combines multiple testing functions (performance measurement, defect detection, electroluminescence testing) into a single integrated testing apparatus. The system merges the illuminator, filter selection mechanism, beam splitter, and detection devices into one unified platform, enabling comprehensive solar cell testing in a single setup rather than requiring separate test stands for each function.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The testing apparatus is designed to perform multiple functions simultaneously: it can measure solar cell performance characteristics, detect defects through various filtering methods, and conduct electroluminescence tests. The rotatable filter wheel with multiple filter options allows the single apparatus to adapt to different testing requirements, making it a universal testing solution that can handle various solar cell types and test conditions.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Measurement precision

If multiple filters are used to test under different spectrums and light intensities, then measurement precision improves, but device complexity increases

Engineering Contradiction:
Improveperformance measurement accuracyVSAvoidfilter selection mechanism complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The filter selection mechanism uses a rotatable filter wheel that can dynamically switch between different filters during the testing process. This dynamic filter selection allows the system to adapt testing conditions in real-time based on the specific measurement requirements, enabling precise control over light spectrum and intensity without requiring multiple static testing setups.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The beam splitter acts as an intermediary device that divides the light path, allowing a portion of the filtered light to reach the solar cell while another portion is directed to measurement devices. This intermediary mechanism enables simultaneous monitoring of light characteristics and solar cell response, improving measurement precision without requiring direct modification of the main optical path.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Productivity

If automated filter selection and positioning is implemented, then testing efficiency improves, but device complexity and cost increase

Engineering Contradiction:
Improveautomated testing speedVSAvoidmotor and encoder system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The motorized filter wheel system includes an encoder that automatically tracks and records the position of each filter in the sequence. This self-service mechanism allows the system to automatically recall and reproduce filter sequences without manual intervention, enabling repeatable automated testing while reducing the complexity of control systems by using the physical position encoding inherent in the filter wheel structure.

Inventive Principle:
Principle #25Self-service

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 efficient and reliable testing of solar cells by allowing for precise control of light intensity and spectrum, improving defect detection and performance measurement, and facilitating automated testing processes.

Implementation Method 1

an illuminator for directing light energy on a solar cell under test

Methodology Applied
Scientific EffectLight: Light

Implementation Method 2

Each filter of the first set of filters is adapted for passing a predetermined percentage of intensity of the light energy from the illuminator onto the solar cell under test. Each of the second set of filters is adapted for testing the solar cell under different spectrums of light.

Methodology Applied
Scientific EffectOptical filtering: Filter (optical)

Implementation Method 3

The beam splitter may direct a predetermined portion of the light from a selected filter of the multiplicity of filters onto the solar cell and may also direct another predetermined portion of the light energy to an apparatus for measuring characteristics of the light

Methodology Applied
Scientific EffectLight splitting: Reflection

Implementation Method 4

Solar cells are photovoltaic devices which convert light energy or photons into electrical power

Methodology Applied
Scientific EffectPhotovoltaic effect: Photovoltaic Effect

Implementation Method 5

The multiplicity of filters further comprises a light blocking filter to perform an electroluminescence test of the solar cell to detect light emission from the solar cell in response to an electric current of a predetermined amperage being applied to the solar cell

Methodology Applied
Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentEP2718697B1Solar cell testing apparatus and method
Publication Date: 2020.07.08 THE BOEING CO
  • EP2718697B1 patent drawingFigure 1
  • EP2718697B1 patent drawingFigure 2
  • EP2718697B1 patent drawingFigure 3

AI summary

A solar cell testing apparatus (200) includes an illuminator (202) for directing light energy on a solar cell (204) under test. The solar cell testing apparatus may also include a device (214) for selectively po¬ sitioning different filters of a multiplicity of filters in an optical path between the illuminator and the solar cell under test to at least one of measure performance and detect any defects in the solar cell. The multiplicity of filters includes a first set of filters (216a) and a second set of filters (216b). Each filter of the first set of filters is adapted for passing a predetermined percentage of intensity of the light energy from the illuminator onto the solar cell under test. The second set of filters being adapted for testing the solar cell under different spec- trums of light.