SC B4 covers High Voltage and Medium Voltage Direct Current systems and Power Electronic equipment for tranmission and distribution systems . The study committee covers AC and DC systems and equipment as well as Power Electronics for other applications such as distribution and Power Quality improvement. DC converters for energy storage are also part of the activities of SC B4. The members of SC B4 come from manufacturers, utilities, transmission system operators (TSOs), distribution system operators (DSOs), consultants and research institutes.