Design of electrical power supply system in a typical petroleum refinery

Abstract

The electrical system shall be designed economically for continuous and reliable services, safely to personnel and equipment, ease of maintenance and operation, minimum power losses, protection of equipment mechanically, interchangeability of equipment and addition of the of the loads. In order to achieve the above goals and obtain the desired results, a scientific study based on different theories and practical experiences will be needed. In this study, the power supply of Transnet Pipeline Terminal 2 (TM2) petroleum refinery in Heidelberg, the criteria and methods of designs of normal networks, electrical equipment and protection of the system will be discussed and investigated. A single line diagram will be presented as the outcome of the design. The single line diagram includes 88kV, 11kV and 400V voltage levels. In the second phase of the design single line diagram is consequently simulated by the ETAP software. The study will cover the following: load flow, short circuit current and motor starting. The intention of this study is to create solution in different ways, electrical loads should be categorized in this energy industry as well as energizing these loads by a stable power supplies. In addition the key role of the short circuit impedance of the transformers in control of the short circuit will be presented. Furthermore the selection procedure of the electrical equipment and accessories including cables, transformers, circuit breaker, relays, and etc. are presented. The following factors such as the size of equipment, losses and voltage drops will be checked by load flow study. A comprehensive study of the short circuit current calculations is implanted and can be observed how the system can be checked by the results of this study. In the dynamic study of the system, the biggest motor starting is simulated and the impacts of the voltage dips due to starting of this motor on the other running motors are shown. Since numerous types of equipment on one hand and the research on the economic matters on the other hand are time consuming, the scope of this report will mainly concentrate on the technical factors and as a results it does not cover the economic aspects. Moreover, high standard engineering in the petroleum industry is essential to design electrical system. It is noted that more economical options are acceptable as long as they end up with the same technical results or better.