| 摘要 |
PURPOSE:To provide a power supply switching method which employs a 3- winding transformer and by which switching between two power supplies can be performed without hits and non-interruption service with the two power supplies can be realized. CONSTITUTION:Two primary windings Pa and Pb of a 3-winding transformer 6 are connected to two power supply systems 1a and 1b whose voltages, frequencies and phases are identical through switches 4a and 4b to couple the two power supplies with each other and supply power to a load 9. If the switches 4a and 4b are so operated as not to be opened simultaneously, switching between the power supply systems 1a and 1b can be performed without hits, so that non-interruption service with the two power supply systems can be realized. |
