Design and testing of fast transfer scheme for Sasol Secunda

Abstract

The paper seeks to design, test and implement a fast transfer scheme for an existing Alpha Olefins substation at Sasol Secunda, Mpumalanga Province, in South Africa. The aim of this design is to switch motor bus bars over to an intact back up supply should the main supply fail and to switch them back again when the main supply is restored. The switchover to the back up supply must be performed as quickly and as smoothly as possible to maintain operation and avoid undue stress on the motor shafts. Using all the specification for the switchover procedures required in Alpha Olefins substation, a fast transfer scheme was designed and tested. To achieve this, the normally open tie breaker was utilised. Included will be the panel design for the control circuits of both incomer panels and High-Speed Transfer Devices (HSTD), Intelligent Electronics Devices, (IEDs) with logics.