IEC 60904-8-1:2017

Overview

IEC 60904-8-1:2017 addresses the measurement of spectral responsivity (SR) in multi-junction photovoltaic (PV) devices. Published by the International Electrotechnical Commission (IEC), this standard provides essential guidance for laboratories, manufacturers, and researchers working with advanced PV technologies involving multiple series-connected junctions. The standard focuses primarily on non-concentrating multi-junction devices but its principles may be applied, where relevant, to concentrating multi-junction PV devices as well. Accurate SR measurement is crucial for evaluating the performance and current-voltage characteristics of multi-junction PV cells, as referenced in related standards such as IEC 60904-1-1.

Key Topics

• Spectral Responsivity of Multi-Junction PV Devices
  Describes methodologies for accurately measuring the SR of each junction within complex PV devices, where each junction responds to different wavelengths.

• Bias Light and Voltage Requirements
  Details the use of bias light (broadband or narrowband) and external bias voltage to isolate and measure the SR of individual junctions within a multi-junction PV structure.

• Measurement Procedures
  Covers measurement setups utilizing continuous or pulsed light sources, and provides best practices for series-connected PV modules. Emphasizes the necessity of lock-in techniques and maintaining stable measurement conditions for precise results.

• Correction Methods
  Discusses the correction of measured SR data to account for effects such as shunting and luminescent coupling, which can impact the accuracy of measurements in multi-junction devices. Procedures for identifying and correcting these factors are outlined.

• Reporting Requirements
  Specifies the essential content for SR measurement reports, including bias conditions, measurement methods, corrections applied, and uncertainty estimation.

Applications

The standard is applicable across the photovoltaic industry for:

• PV Device Characterization
  Ensures reliable characterization of multi-junction PV cells and modules, supporting accurate analysis of performance under various irradiation conditions.

• Research & Development
  Guides researchers in developing and testing new multi-junction PV materials and device architectures, facilitating technological innovation and efficiency improvements.

• Quality Assurance & Certification
  Provides laboratories and manufacturers with harmonized methods to certify multi-junction PV products, enabling consistency and comparability across the industry.

• Compliance & Traceability
  Enables organizations to comply with international standards for PV device measurement, supporting traceability and confidence in technical data provided to stakeholders and regulatory authorities.

Related Standards

Several IEC standards are referenced within IEC 60904-8-1:2017, providing a comprehensive framework for PV device measurement:

• IEC 60904-8 – Photovoltaic devices – Measurement of spectral responsivity of a photovoltaic (PV) device
  (Covers single-junction PV devices; forms the basis for multi-junction measurements.)

• IEC 60904-9 – Photovoltaic devices – Solar simulator performance requirements
  (Defines requirements for the light sources used in PV measurements.)

• IEC 60904-1-1 – Photovoltaic devices – Measurement of current-voltage characteristics of multi-junction PV devices
  (Addresses current-voltage measurements specifically for multi-junction structures.)

• IEC TS 61836 – Solar photovoltaic energy systems – Terms, definitions and symbols
  (Provides standardized terminology for PV energy systems.)

By adhering to IEC 60904-8-1:2017, professionals in the photovoltaic sector can ensure higher precision and reliability in the measurement of spectral responsivity for multi-junction PV devices, thereby supporting the advancement and commercialization of high-efficiency solar technologies.