6.1. ATP Load Flow (6-bus example)

Contributor: Ralph Folkers, SEL, USA

Keywords: Load flow, ATPDraw

Summary: The Alternative Transients Program (ATP) has a LOAD FLOW subroutine that allows a normal case to be initialized with PK, QK, VK and/or THETAK constraints before the case is solved.  The load flow solution is printed in the *.LIS output file and the case is solved with the load flow constraints as the initial condition.  This subroutine is described in the ATP Rule Book Chapter X.

The example is a six-bus AC load flow taken from chapter four of Power Generation Operation and Control by Wood and Wollenberg, published in1984 by John Wiley & Sons.
In the ATP system, this example uses a distributed parameter transposed line model.  This was selected for ease of data input, but any line model will work.  The line model requires positive and zero sequence impedance in Ohms and capacitance in micro-Mhos. After converting the data, create the system in ATPDraw and enter the data.  The initial source values are all set to [1.05*230000*SQRT(2/3)].  At this point, the system is just like any other.  Figure below shows the system.


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