DC circuit breakers (DCCB) and fault current limiters (FCL) are typical novel DC protection equipment with nonlinear response

and their transient time scales in DC short-circuit faults can reach the microsecond level

so it is necessary to use the small-step method in the simulation. The existing nonlinear simulation methods can hardly balance the accuracy and execution time

which will directly limit the scope of the application. This paper proposes the concepts of “real component” and “virtual component” and their application methods in nonlinear component modeling. Specifically

nonlinear/time-varying components are equivalently transformed using adaptive tuning of equivalent admittance and history current source parameters to accurately realize nonlinear components modeling under fixed-admittance constraints. In addition

the proposed method has the advantage of eliminating the need for network decoupling and iteration. Test cases show that the proposed method in this paper accurately and efficiently realizes the nonlinear simulation of various novel DC protection equipment with a small step of 1 μs

which improves the simulation accuracy and reduces the execution time compared with the traditional method.