Large-Scale Integration of Power Electronic Interface Devices: Technical and Regulatory Challenges, and Solutions from the Perspective of Grid Operators.

Sammanfattning

The need for a global energy transition has driven the rapid adoption and large-scale integration of inverter-based generation (IBG), consisting primarily of solar photovoltaic and wind power, into transmission level grids. Unlike conventional synchronous generation, IBG connects to the grid through electronic converters, modifying the dynamics of current power systems. This change introduces technical, economic and regulatory challenges that current grid infrastructure is not fully equipped to address. In addition, an increasing number of grid-connected technologies also interface through converters, which collectively form the power electronic interface device group (PEID), where both generation and consumption devices are found, with generation devices having the more significant impact on grid behavior. The technical challenges described in this thesis are divided into three main groups: stability, reliability and quality. The stability challenges include low inertia, reduced short circuit current, lack of reactive power support, fault ride-through, reduction in the transient stability and oscillations. Reliability is divided into two areas: supply adequacy and supply security. Finally, power quality addresses voltage fluctuations and harmonics. Economic and regulatory challenges have been more briefly addressed. This thesis presents a systematic literature review with the objective of mapping the relationships between the challenges and the measures that have been implemented in response, rather than generating new technical knowledge. The research has been based on articles and technical reports published after 2010, using Scopus, IEEE Xplore, Web of Science and MDPI. The examined solutions include energy storage systems (ESS), grid forming inverters (GFMI), flexible AC transmission (FACTS) devices, synchronous condensers (SynCons) and high voltage DC (HVDC) links. Solutions regarding the regulatory and market mechanisms also have been reviewed, including grid code requirements and ancillary service markets. The findings demonstrate that no single technology or measure can address all identified challenges simultaneously. For effective large-scale IBG integration, the coordinated deployment of various solutions across the technical, regulatory and economic dimensions is required. In addition, the regulatory area varies significantly across jurisdictions, limiting the transferability of conclusions between grids. Finally, the study of the interaction between co-deployed technologies remains insufficient. The study concludes that the developed framework and the mapping of challenges and solutions across the aforementioned three categories represents a modest but structured contribution to the systematic understanding of this evolving field. Future work based on this study could include case studies of specific national grids, quantitative modelling of co-deployed solutions and deeper research in the ENTSOE regulatory context.