Reconfigurable Solar Cell Strings for Stable Lifetime Voltage

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional solar cell arrays are designed with a fixed number of solar cells to produce a required output voltage, leading to inefficiency as the radiation damage and operating temperature change over the lifespan of the array, resulting in unused solar cells and varying voltage outputs.

Innovation Solution

A solar cell array design that allows for reconfigurability by using switches to split the solar cells into multiple strings and alter the current flow path, enabling the adjustment of string length to maintain optimal voltage output throughout the array's lifespan.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If solar cells are arranged in fixed-length strings to produce required output voltage, then the array can meet the voltage requirement under worst-case conditions, but solar cells become unused and power output decreases as radiation damage accumulates and temperature changes

Engineering Contradiction:
Improvevoltage output stabilityVSAvoidpower output
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent implements dynamic reconfiguration of solar cell strings by introducing switches that can change the number of solar cells in series connections based on operating conditions. This allows the array to adapt its voltage output dynamically, transitioning from fixed-length strings to variable-length strings, thereby maintaining optimal power output throughout the array's lifespan despite radiation damage and temperature variations.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the electrical configuration parameters of the solar cell array by allowing the string length (number of series-connected cells) to vary. Through controlled switching, the system adjusts the series connection count to optimize voltage and power output under different operating conditions, rather than maintaining a fixed parameter configuration designed for worst-case scenarios.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If solar cells are sized for worst-case environments (highest radiation dose and temperature), then the array can maintain voltage output under extreme conditions, but approximately 18% of solar cells are not producing usable power at the beginning of operation

Engineering Contradiction:
Improvevoltage output under extreme conditionsVSAvoidunused solar cell capacity
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The system transitions from a static configuration designed for worst-case conditions to a dynamic configuration that adapts to actual operating conditions. By using switches to reconfigure string lengths, the array can utilize nearly 100% of solar cell capacity during low-radiation periods while maintaining voltage stability under high-radiation conditions, thereby eliminating the 18% energy loss inherent in fixed-size designs.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The solar cell array is designed to perform multiple functions across different operational phases: during early operation with minimal radiation damage, shorter strings are used to maximize power output; during later operation with accumulated radiation damage, longer strings are used to maintain voltage requirements. This multi-functional capability allows the same physical array to optimize for different conditions throughout its lifespan.

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

3Ease of manufacture

If the number of solar cells in strings is fixed, then the manufacturing process is simple, but the array cannot adapt to changing operating conditions throughout its lifespan

Engineering Contradiction:
Improveassembly simplicityVSAvoidreconfigurability
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent divides the solar cell array into modular segments with switches positioned at strategic points along the strings. This segmentation allows independent control of different sections, enabling flexible reconfiguration into various string lengths while maintaining a systematic and organized structure that does not significantly complicate the manufacturing process.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The switches serve as intermediary components that mediate between the fixed physical arrangement of solar cells and the desired variable electrical configuration. These intermediary elements enable reconfigurability without requiring physical movement or repositioning of the solar cells themselves, thus maintaining manufacturing simplicity while achieving adaptability.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 reconfigurable design ensures that all solar cells contribute to power generation throughout the array's lifespan, optimizing power output and extending the array's operational efficiency.

Implementation Method 1

A solar cell array absorbs light from a light source and generates an electrical output in response

Methodology Applied
Scientific EffectPhotovoltaic effect: Photovoltaic Effect

Data Source

PatentEP3416198B1Solar cell array with changeable string length
Publication Date: 2025.01.22 THE BOEING CO
  • EP3416198B1 patent drawingFigure 1
  • EP3416198B1 patent drawingFigure 2
  • EP3416198B1 patent drawingFigure 3A~3B

AI summary

A solar cell array comprised of one or more solar cells (14) attached to a substrate. The substrate includes one or more electrical connections to the solar cells and one or more switches (54) for changing a string length for one or more of the solar cells by altering a current flow path between the one or more of the solar cells and one or more of the electrical connections.