Integrating three-phase load flow and short-circuit current calculation for a low voltage system

• Published in: Electric power systems research Vol. 53; no. 2; pp. 123 - 132
• Main Authors: Teo, C.Y., He, B.G.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.02.2000
• Subjects: Fault current calculation; System earthing in low voltage system; Three-phase load flow; Fault current calculation; System earthing in low voltage system; Three-phase load flow
• ISSN: 0378-7796; 1873-2046
• DOI: 10.1016/S0378-7796(99)00050-4

This paper summaries a dedicated approach to solve three-phase load flow and calculate unbalanced short-circuit current simultaneously for low voltage systems without using the conventional symmetrical components. As the unbalanced load and the neutral and shock voltages have to be modeled, the network equations including the representation of the neutral and grounding conductors are formulated entirely in phase coordinates. Test results demonstrate the ability in modeling the untransposed cable parameters and the influence of the unbalanced load currents. More accurate results can thus be obtained as compared with other methods of calculation. Many interesting phenomena such as unbalanced load flow, different voltages appearing at various sections of the neutral and grounding conductors, effects of the disconnection of the source earthing, and any open-circuit fault can all be simulated.