A review of smart inverter capabilities for managing high levels of distributed energy resource integration in South Africa’s power grid

Abstract

Distributed energy resources (DERs), including solar panels, wind turbines, and battery storage, are becoming more prevalent in power grids. This increased penetration necessitates a closer look at how they impact the grid's operation. Power grid operators face challenges in ensuring the secure operation of the network in the presence of DERs. This includes managing voltage fluctuations, integrating diverse energy sources, and preventing grid overloads. This paper reviews the impacts of DERs on power grid operation and discusses strategies for enhancing the integration of DERs in South Africa’s grid. The strategies involve technology solutions, grid management techniques, and policy changes that facilitate the seamless integration of renewable energy sources. Smart inverters are highlighted as an essential component of the solution. Their advanced capabilities play a central role in managing voltage, frequency, and other aspects of power quality, which is critical when integrating DERs. The paper offers a comprehensive overview of the challenges of integrating inverter-based DERs into the power grid, highlighting lacks and deficiencies in existing South Africa power grid codes and standards and discussing solutions – thus paving a way for future investigations and developments. Eight international regulations are examined and compared, exposing the lack of a worldwide harmonisation and a consistent communication protocol. The paper calls for the evolution of power grid codes to adapt to the changing energy landscape and to harness the benefits of DERs and advanced smart inverter capabilities. This involves updating regulations and standards to ensure grid stability and reliability while accommodating renewable energy sources. The review can aid power utilities and regulators in making informed decisions in enhancing grid-connected DERs and ensuring safe and secure grid operation.

Keywords

• smart grid
• reactive power
• voltage control