Control strategy of UPFC based on power transfer distribution factor

In practical engineering application, trial method is widely used to determine the control value of unified power flow controller (UPFC in short). Since the calculation is based on offline typical data, the trial method is inefficient and less accurate, which could not adjust to the changing operating conditions. In order to make up for the deficiency, this paper proposes a novel UPFC control strategy based on power transfer distribution factors. First, the anticipated line tripping fault throughout the grid is scanned and the N-1 overload lines are marked. Then, in regard to each overload condition, a certain UPFC control value is calculated based on power transfer distribution factors. The anticipated control list could be formed and updated according to online EMS data. When a line tripping fault is detected, simply by searching the control list, a condition could be matched and the UPFC could immediately be activated to eliminate the line overload. This method mentioned above could provide decision-making support to power-grid dispatching institutions. The results of a simulation example shows that the method is efficient and utilisable.