| 摘要 |
A conventional cable 1 comprises three conductive cores 2a, 2b, 2c, each provided with a respective conductive sheath 3a, 3b, 3c, which are together housed within an outer insulating sheath. The three-core cable 1 is used to transmit electric power in the form of dc current and single-phase ac current. A first one of the conductive cores 2a is used to transmit dc current, while a second conductive core 2b is used to transmit the return dc current. The third conductive core 2c is used to transmit the single-phase ac current. The return ac current is transmitted along all three conductive outer sheaths 3a, 3b, 3c in parallel. The cable is used to transmit dc current from a wind turbine generator to a substation where it is converted to ac before connecting to the mains electricity grid. The ac current is used to power auxiliary circuitry of the wind turbine generator 5 when the output of the turbine generator 5 falls below a give value. |
