| 摘要 |
<p>A method for operating a doubly-fed machine by determining its rotational speed (n<SUB>act</SUB>), forming a rotational speed reference (n<SUB>ref</SUB>), measuring network voltage and current, and calculating network active power (P<SUB>act</SUB>) and reactive power (Q<SUB>act</SUB>). Thereafter, calculating shaft torque (T) based on active power (P<SUB>act</SUB>) and rotating speed (n<SUB>act</SUB>), forming a frequency reference (F<SUB>ref</SUB>) for the inverter based on machine rotating speed (n<SUB>act</SUB>), rotating speed reference (n<SUB>ref</SUB>), shaft torque (T), and the known pole pair number and network frequency, forming a reactive power reference (Q<SUB>ref</SUB>) for the machine. Forming an Ir compensation reference (IR<SUB>ref</SUB>) for the inverter on the basis of the reactive reference (Q<SUB>ref</SUB>) and the reactive power (Q<SUB>act</SUB>), and controlling the inverter to produce rotor voltage based on frequency reference (F<SUB>ref</SUB>) and the IR compensation reference</p> |
