Who are leading oil filled transformers manufacturers worldwide?

Leading manufacturers include Hitachi Energy, Siemens Energy, GE Grid Solutions, Hyundai Electric, Mitsubishi Electric, Toshiba, CG Power, and TBEA. These companies supply oil filled transformers for transmission, generation, and industrial networks worldwide. They offer custom designs, advanced monitoring, and compliance with international grid standards. Regional manufacturers also play key roles in utility projects depending on market and voltage class.