What voltages are typical for the DWP Transmission System?

What voltages are typical for the DWP Transmission System?

• A. 138 kV or 230 kV
• B. 34.5 kV
• C. 4.8 kV
• D. 480 V

Answer: (A)

Transmission systems move bulk power over long distances, so they use high voltages to keep currents low and reduce I^2R losses. In the Los Angeles Department of Water and Power network, the bulk transmission voltage levels are typically very high, around 138 kV or 230 kV. The other voltages listed are associated with lower-stage electrical delivery: 34.5 kV is a mid-range or sub-transmission level used in some grids, while 4.8 kV and 480 V are distribution voltages used closer to customers after stepping down from the transmission level. So the high-voltage values of 138 kV or 230 kV best represent the DWP Transmission System.

Transmission systems move bulk power over long distances, so they use high voltages to keep currents low and reduce I^2R losses. In the Los Angeles Department of Water and Power network, the bulk transmission voltage levels are typically very high, around 138 kV or 230 kV. The other voltages listed are associated with lower-stage electrical delivery: 34.5 kV is a mid-range or sub-transmission level used in some grids, while 4.8 kV and 480 V are distribution voltages used closer to customers after stepping down from the transmission level. So the high-voltage values of 138 kV or 230 kV best represent the DWP Transmission System.