Power Quality Issues Associated with Inverter Duty Transformer

However, a number of these IDTs have experienced failures during commissioning and operation, despite compliance with existing national and international standards such as IEEE

Std C57.159-2016. Currently, there is limited publicly available data on IDT failures at both national and international levels.

To address this gap, a technical case study was undertaken involving various stakeholders to conduct (a) Literature review (b) Survey of equipment failure at SPV plants and (c) Power quality monitoring at selected sites through SPV plant owner participation (d) Analysis of power quality audit with industry academia collaboration (e) to analyse the root causes through modeling and analysis. Also, recently, CIGRE has established a Working Group WG

N° A2.68 to investigate “Lower Voltage Generator Step Up Transformers installed in Wind farms and Photovoltaic Parks“ and publish findings and recommendations by Autumn 2025. These study findings will help CIGRE national committees revise the existing standards OR develop new standards to implement recommendations across utilities. This paper presents the research methodology used in this technical study, survey results, and power quality audit analysis at various sites and their outcome through three case studies : (1) power quality audit by researcher (2) power quality audit by OEM (3) power quality audit by industry to provide different perspective from stakeholder point of view. This paper discusses the challenges and opportunities identified during the power quality audit, highlight the discrepancies between current standards and field practices, and offers recommendations for:

Continuous real-time power quality monitoring at a grid connected SPV plant b) Implement power quality management as per IEC 63222 during the planning and commissioning stages c) Perform power quality data analytics for predictive maintenance to prevent IDT failures d) Conduct root cause analysis and recommend necessary changes to the existing standards in case of failures a) The outcomes of this study are intended to support CIGRE WG A2 and C4, national study committees, and other stakeholders such as IEC and IEEE in developing guidelines, best practices and standards to prevent IDT failures in the future. Also, implementing power quality management at renewable energy plants to enable AI driven PQ data analytics will reduce asset and financial losses in the evolving SMART GRID landscape.