Preface: 20^th Conference on Power System Engineering

The Conference on Power System Engineering has a long-term tradition. It is an annual meeting of professors and experts from departments and universities where power system engineering is taught. The 20th year of this event was held in Pilsen (Czech Republic) between 7th and 9th September 2021 and was hosted by Department of Power System Engineering of Faculty of Mechanical Engineering, University of West Bohemia in Pilsen.