Photovoltaic Module Ambient Temperature Estimation Without Sensors

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Integrating a dedicated temperature probe into photovoltaic systems for temperature measurement poses difficulties and incurs additional costs, and existing methods for estimating ambient temperature using photovoltaic modules require extensive calibration and recalibration due to changes in module type or dimensions.

Innovation Solution

A method using a unique mathematical model with fixed coefficients, defined by the relationship \( T_a = a imes V_{oc} + b imes \ln(I_{sc}) + c imes I_{sc} + e \), where \( e \) is a function of the ideality factor of the equivalent diode, estimates ambient temperature based on short-circuit current and open-circuit voltage measurements, eliminating the need for a dedicated temperature sensor.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a dedicated temperature probe is integrated into the photovoltaic system, then temperature measurement capability is improved, but device complexity and integration difficulty increase

Engineering Contradiction:

Improvetemperature measurement capabilityVSAvoidintegration difficulty

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent combines the temperature measurement function with the existing photovoltaic module by utilizing its electrical characteristics (Isc-Voc pairs) rather than adding a separate temperature probe. The photovoltaic module serves dual purposes: power generation and temperature sensing, thereby reducing device complexity while maintaining measurement capability.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The photovoltaic module measures temperature using its own inherent electrical properties without requiring external dedicated sensors. By analyzing the relationship between short-circuit current and open-circuit voltage, the module self-determines its temperature, eliminating the need for separate measurement devices and simplifying integration.

Inventive Principle:

Principle #25Self-service

2Device complexity

If existing temperature estimation methods using photovoltaic modules are used, then device complexity is reduced, but measurement precision deteriorates due to extensive calibration requirements

Engineering Contradiction:

Improvesystem simplicityVSAvoidtemperature estimation accuracy

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent changes the approach from using single-parameter measurements to utilizing paired Isc-Voc measurements. By analyzing the combination of short-circuit current and open-circuit voltage pairs, the method achieves accurate temperature estimation without requiring extensive calibration, as the dual-parameter approach inherently compensates for module-specific variations.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent develops a universal temperature estimation method that works across different photovoltaic module types and dimensions without requiring recalibration. The mathematical model based on Isc-Voc relationships is designed to be module-agnostic, allowing the same approach to be applied universally to various PV technologies and configurations.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Device complexity

If photovoltaic module electrical characteristics are used for temperature measurement, then dedicated temperature sensors are eliminated, but measurement precision may be affected by irradiance variations

Engineering Contradiction:

Improvesensor countVSAvoidtemperature measurement accuracy

Core Design Contradiction:

Device complexityVSMeasurement precision

Solution Approach 1:

The patent performs measurements at specific operating points (short-circuit and open-circuit conditions) rather than attempting to measure at arbitrary operating points. By utilizing these extreme conditions where the module's electrical characteristics are most distinct and less sensitive to irradiance variations, the method achieves accurate temperature measurement without requiring additional sensors.

Inventive Principle:

Principle #16Partial or excessive action

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

Accurately estimates ambient temperature with minimal computing resources, adapting to different types of photovoltaic modules without extensive recalibration, and simplifying implementation by using easily measurable ideality factor parameters.

Implementation Method 1

a) measure the short-circuit current Isc and the open-circuit voltage Voc of the photovoltaic module

Methodology Applied

Scientific EffectPhotovoltaic effect: Photovoltaic Effect

Data Source

PatentEP4481344B1Method and system for measuring temperature using a photovoltaic module

Publication Date: 2025.10.29 COMMISSARIAT A LENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES

Figure 1
Figure 2~3

AI summary

This description relates to a method for determining the outside ambient temperature Ta in a system comprising a photovoltaic module (104), comprising the following steps: a) measuring the short-circuit current Isc and the open-circuit voltage Voc of the photovoltaic module (104); b) calculating the outside ambient temperature Ta, using an electronic processing device (110), as a function of the value of the short-circuit current Isc and the value of the open-circuit voltage Voc measured in step a), using a single mathematical model with two input variables, the mathematical model comprising fixed coefficients, one of said fixed coefficients being defined by a function of an ideality factor of an equivalent diode of the photovoltaic module.