Short Circuit Force Calculation (Mechanical effects)

An outdoor switchyard has many overhead live conductors strung between two Gantries or Equipment. These conductors carry rated current under normal condition. Under abnormal conditions such as faults, the conductors need to carry the short circuit currents for very short duration of 1 sec or 3 sec. When very high fault current passes through two parallel conductors either in same direction or opposite direction, a mechanical force of repulsion or attraction takes place between the conductors. The magnitude of the mechanical force generated during fault or just after the fault is isolated can be calculated by methods specified in IEC 60865, part-1 and 2. Such force between the conductors gets transferred to the support structures and hence the support structure must be designed to withstand both the normal stringing tension at full wind and ice (if applicable) condition and also the mechanical effects of the short circuit force during faults.

Satcon over the last two decades has mastered preparation of such calculations. Our senior engineers have the knowledge and standards to carry out this calculation for extra high voltage substations of any voltage level upto 765kV.