The problem of numerical simulation of digital protective relay and its analog–digital (hybrid) solution

Settings determination for numerical transformer differential protection via its detailed mathematical model

“…All cases of the external SCs are characterised by the transition of the FCs to the right side under the TC and their swings due to the asynchronous operation of closely installed SMs. Nevertheless, there was no false tripping in these modes, except for the case of an external three-phase SC which is not shown in this paper but could be found in [25].…”

“…5. An increase in the number of points of the characteristic Z µ = f (i µ ), a change in the slope of this characteristic, tested in [25], did not completely exclude this phenomenon.…”

“…Such a method is used for differential equations solution in the HRTSim [8]. The mathematical model is implemented in a specialised hybrid processor for numerical RP (SHP NRP) simulation [25], which is compatible with HRTSim. The simulator HRTSim and SHP NRP were used in this study as a testbed for solving the issue of NTDP setting up.…”

“…Adding new models of RES, flexible AC transmission system, HV direct current systems etc. to the EPS model makes it possible to analyse their influence on the functioning of a specific RP and to take this influence into account in its settings in a natural way [25]. It should also be noted that this approach has to be adapted to a specific type of protection: differential, distance etc., since each relay has unique operating features, and, accordingly, settings.…”