Global SF6 Gas Insulated Transformer Market By Type (Medium Voltage (Up to 72.5 kV) , High Voltage (72.5 kV to 220 kV) , and Extra High Voltage (Above 220 kV)), By Application (Utility, Industrial, and Commercial), By Region, and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2019-2028