Dual Stationary Frame Control of Inverter-based Resources for Reliable Phase Selection

Phase selection is a significant protection element, which determines faulty phase(s). However, commercial phase selection methods (PSMs) are susceptible to failure in the presence of inverter-interfaced resources (IBRs) because their fault currents possess different characteristics than conventional generation sources. This paper develops a dual current controller (DCC) in the stationary frame to make the traditional current-angle-based PSM operate correctly at the relay location without frame transformation. First, the fault type is determined at the IBR. Then, the reference angle of the negative-sequence current is determined to achieve the current-angle-based PSM requirements. Subsequently, the negative-sequence current reference in the stationary frame is determined according to its current reference angle and its maximum current limit. Besides, the positive-sequence current is determined based on the active and reactive current references. Lastly, the sinusoidal reference currents are tracked accurately using a proportional-resonant (PR) control. Comprehensive time-domain simulations are used to validate the accuracy of the proposed DCC under different fault conditions.