Patent ID: 8798800

Claim:
A method for providing improved control of a power transmission system having a computer connected to a first group of measurement units in a first geographical area and providing a first set of on-line measured phasors and the computer connected to a second group of measurement units in a second geographical area and providing a second set of on-line measured phasors, where the first and second groups of measurement units each include at least two measurement units and the phasors in the first and second sets are generated simultaneously, the method comprising the steps of: receiving at the computer the first set of phasors from the first group of measurement units and the second set of phasors from the second group of measurement units, aligning the first and second sets of phasors with each other in time via software executing on the computer, comparing the number of phasors in each set of phasors with a corresponding phasor minimum number threshold with software executing on the computer, the computer determining that a first control condition is fulfilled if each such phasor number threshold has been exceeded, and the computer generating a control signal if at least said first control condition is fulfilled, where this control signal is based on the obtained phasors in the first and second sets and provided for use in inter-area oscillations damping in relation to the first and the second geographical areas.