Electrical power converting device and method to accommodate voltage variations in electricity networks

摘要

A converter device for power conversion in a power plant, such as a wind turbine, is provided. The converter device is configured for converting an electrical input power to an electrical output power. The converter device may be configured for receiving mechanical input power or, according to another embodiment, may be configured for receiving electrical input power. The converter device includes a voltage input for receiving a voltage signal, which is indicative of a voltage in a electricity network to which the converter device is coupled during operation in order to provide the electrical output power to the electricity network The converter device includes a controller being configured for setting a reactive component of the electrical output power depending on the voltage signal according to a out-of-band reactive current gradient if the voltage indicated by the voltage signal is outside a predetermined voltage band.

主权项

1. A converter device for converting an electrical input power to an electrical output power, the converter device comprising:
a voltage input for receiving a voltage signal, said voltage signal being indicative of a voltage in an electricity network to which the converter device is coupled during operation in order to provide said electrical output power to said electricity network; a controller being configured for setting a reactive component of said electrical output power depending on said voltage signal according to a predetermined out-of-band reactive current gradient if the voltage indicated by the voltage signal is outside a predetermined voltage band, thereby varying the reactive component so as to vary a reactive current according to the predetermined out-of-band reactive current gradient; wherein the predetermined out-of-band reactive current gradient is defined as change of reactive current per voltage unit of a change in the voltage indicated by the voltage signal, wherein the predetermined voltage band is set to a width which varies as a percentage of a rated value of the voltage signal.