| 摘要 |
A method for detecting a three-phase islanding state in a three-phase electricity network, the method comprising supplying power into a three-phase electricity network (EN) by a power supply assembly (PSA) having an output frequen-cy (É PSA ), controlling the output frequency (É PSA ) of the power supply assembly (PSA) with a frequency reference signal (É ctrl ) adapted to deviate the output frequency (É PSA ) of the power supply assembly (PSA) from a grid frequen-cy (É grid ) representing a frequency of a common electricity network (GRD) whose part the three-phase electricity network (EN) is in normal operating conditions, and detecting a three-phase islanding state in the electricity network (EN) if the output frequency (É PSA ) of the power supply assembly exits an allowable value range. During a normal operating state of the electricity network (EN) the frequency reference signal (É ctrl ) depends on an active output current (i p,É ) of the power supply assembly (PSA). |
