Adaptive Current Differential Protection for Active Distribution Networks Based on Compensation Coefficient

The integration of distributed generation (DG) challenges traditional protection schemes in distribution networks. This paper proposes an adaptive current differential protection scheme suitable for active distribution networks. First, the impact of fault characteristics from different types of DGs on distribution networks is analyzed. The limitations of conventional differential protection after the integration of inverter-interfaced distributed generators (IIDGs) are investigated. Based on the control strategies and output characteristics of IIDGs, a novel differential protection criterion using an adaptive compensation coefficient is proposed. The braking coefficient is reconstructed using the random forest algorithm, forming an adaptive current differential protection scheme for active distribution networks. A simulation model of an active distribution network is developed, and the operational characteristics of the proposed protection scheme under various fault types and locations are analyzed. Simulation results demonstrate that the proposed scheme improves sensitivity is higher for high-impedance internal faults compared to conventional methods.