Sequence networks to the calculation of two-simultaneous faults at the same location

•We present a new equivalent circuit in symmetrical components.•We demonstrate all stages of the proposed equivalent circuit.•We tested the proposed equivalent circuit.•We compared the new equivalent circuit with the traditional method.•We have obtained good results with the new equivalent circuit.

The system of symmetrical components (012-system) can be used to simulate symmetrical and asymmetrical operation of power systems. However, the classical literature of Power Systems Analysis does not present one equivalent circuit in 012-system to two-simultaneous faults where there are a single-line-to-ground fault and a bolted line-to-line fault. This paper presents the equations and the new equivalent circuit mentioned. In addition, we present a comparison of results between the proposed approach and the output of the commercial software ANAFAS, which validates the methodology. We find evidence that the new equivalent circuit developed can substitute the equivalent circuits used to calculate a single line-to-ground fault and a bolted line-to-line fault.