A general calculation method for short-circuit faults is proposed
which accounts for multi-sequence network coupling and dynamic control strategy modeling. Firstly
fault equivalent models of multiple types of DGs are established
and the impacts of their low-voltage ride-through and negative-sequence current suppression strategies on sequence component networks are analyzed. Then
based on the superposition theorem
the fault network is decomposed into normal component and fault component networks
and the sequence network boundary condition equations for different short-circuit types are derived to construct a composite sequence network model incorporating IBDGs. Finally
through iterative correction of node voltages and DG injection currents
the short-circuit fault solution is achieved. Simulation results show that the proposed method has good applicability in complex active distribution networks with multiple types and multiple points of DG integration
and the calculation errors of short-circuit faults are all less than 3%.
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