Experimental evaluation of the alternative generalized alpha plane for double-circuit series-compensated transmission lines

摘要

This paper presents an experimental evaluation of an alternative generalized alpha plane formulation applied to series compensated double circuit transmission line differential protection. This line configuration introduces major challenges to the protection system, due to the proximity between circuits, in addition to the series compensation effects. Faced with these challenges, the performance of line differential protection allied to the generalized alpha plane strategy is evaluated in a commercial relay. Aiming to do so, various faults scenarios were simulated in a 500 kV series compensated double-circuit, modelled on Alternative Transients Program (ATP). Furthermore, the alternative formulation was directly implemented in the relay and its performance was roughly compared with the original proposal. The obtained results reveal an enhanced performance for the phase elements in comparison with the original method, besides having a more well-behaved response in the alpha plane and a simpler formulation.