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5.1: Power Flow

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    55581

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    Power flow in a network is determined by the voltage at each bus of the network and the impedances of the lines between buses. Power flow into and out of each of the buses that are network terminals is the sum of power flows of all of the lines connected to that bus. The load flow problem consists of finding the set of voltages: magnitude and angle, which, together with the network impedances, produces the load flows that are known to be correct at the system terminals. To start, we view the power system as being a collection of buses, connected together by lines. At each of the buses, which we may regard as nodes, we may connect equipment which will supply power to or remove power from the system. (Note: in speaking of power here, we are really referring to complex power, with both real and reactive components). If we have made a connection to a given system node (say with a generator), the complex power flow into the network at node \(k\) is:

    \[\ \mathbf{S}_{k}=P_{k}+j Q_{k}=\mathbf{V}_{k} \mathbf{I}_{k}^{*}\label{1} \]

    This page titled 5.1: Power Flow is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by James Kirtley (MIT OpenCourseWare) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.