Photovoltaic systems – Guidelines for effective quality assurance of power conversion equipment
|Publication Date:||1 November 2019|
|ICS Code (Solar energy engineering):||27.160|
This document lays out recommendations for best practices for product realization, safety, customer satisfaction, and stakeholders' relationship used in the manufacture of power conversion equipment (PCE).
This document captures key requirements customers would like to see completed to ensure high-quality products, specifically, that the products have the documented properties, including properties needed to give customer satisfaction with regard to the warranty.
The object of this document is to provide more confidence in the ongoing consistency of performance and reliability of certified power conversion equipment. The requirements of this document are defined with the assumption that the quality management system of the organization has already fulfilled the requirements of ISO 9001 or equivalent quality management system. These guidelines also form the basis for factory audit criteria of such sites by various certifying and auditory bodies.
This document covers manufacture of electronic power conversion equipment intended for use in terrestrial PV applications. The term PCE refers to equipment and components for electronic power conversion of electric power into another kind of electric power with respect to voltage, current and frequency. This document applies to PCE in both indoor and outdoor open-air climates as defined in IEC 60721-2-1 and IEC 60721-3-3. Such equipment may include, but is not limited to, DC-to-AC inverters, DC-to-DC converters and battery charge converters.
This document covers PCE that is used with PV arrays. The equipment may also be connected to other DC source or load circuits such as batteries. All parts of the PCE are included (e.g. connectors and software). This document may be used for accessories for use with PCE, except where more appropriate standards exist.
The object of this document is to define steps for providing assurance that:
• The customers' expectations are identified and the product is designed to meet those expectations,
• The performance characteristics and method of meeting the customers' expectations (e.g. efficiency) are identified,
• The specifications are either in conformance with the related standards or mentioned by the manufacturer on the data sheet or other product literature,
• The product has each of the properties described on the data sheet or other product literature, and
• The product has been designed and manufactured to retain those same properties after normal and reasonable environmental stresses experienced in the field (including worstcase typical temperatures, thermal cycling, corrosive conditions, over voltages/currents on DC and AC lines, transportation and installation, etc.) as well as survive stresses coming from the grid within the promise of the warranty.
To achieve these goals, this document requires:
• Analysis to identify potential failure modes and creation of a plan to prevent these during the time of the design lifetime,
• A documented change management control process to address raw material or manufacturing changes arising both internal and external to the organization,
• A documented supplier quality management process with integrated performance standards that uses continuous improvement to enhance overall product quality,
• A documented manufacturing process with workmanship standards that uses continuous improvement to enhance product quality,
• A documented manufacturing process that includes steps that identify when the process has gone out of control and high-level measures to follow to bring the process back in control as specified by an out-of-control action plan (OCAP). This includes measurements that ensure that the products have the defined properties including test results expected for certification, standards and warranty, and
• Testing of software to ensure that it works in the anticipated situations.