Special Issue on Modeling and Analysis of Interaction Between Grids and Grid-Connected Power Electronics Converters in Distribution Networks

Increasing penetration of grid-connected renewable energy systems and smart loads based on power electronics converters (such as solar inverters, wind turbines, and variable speed motor drive systems) has been increasing in low- and medium-voltage power networks. High penetration of power electronics converters has the potential to degrade the power quality of grids introducing strong resonances in grids, waveform distortion (e.g., harmonics), transients, or flicker, which pose severe risks to the distribution networks and connected equipment. Especially waveform distortion above and below 2 kHz, as well as fast transients, can cause failures in grid communication, degradation of equipment such as distribution transformers, and losses of energy, and can affect system protection. This further faces the community with challenges in the measurement of voltage and current as well as in maintaining the requirements of the electricity codes and contractual obligations between network operators and users. The automobile industry is going through an incredible transformation from internal combustion engines (ICEs) to all-electric vehicles (EVs). Some European countries have decided to ban all petrol-powered cars in the next 25–40 years. The fast-growing penetration of EVs charger will result in new challenges in distribution networks and connected loads. For example, grid impedance and its variation have a significant impact on grid-connected power converter behavior, interaction, stability, and harmonic emission and immunity. Thus, grid impedance modeling and estimation are required for existing and future analysis of distribution networks with a high number of grid-connected inverters. This Special Issue aimed to emphasize and document the latest research that addresses the abovementioned emerging challenges. In response to the call for articles, the total number of manuscripts received was 53, and 15 articles were accepted for publication. The submitted manuscripts came from 19 different countries, covering most of IEEE regions, i.e., Australia, China, Hong Kong, India, Bangladesh, Iran, Turkey, Finland, Sweden, Denmark, Belgium, France, Germany, the U.K., the United States, Canada, South Africa, Mexico, and Chile. From the accepted articles, all 15 articles address issues directly relevant to this Special Topic. Broadly, the articles can be categorized as follows: control and stability, assessment of frequency-dependent impedance, power quality aspects in distribution networks, and grid distortion impacts on power converters.