1. Continuation Power Flow (CPF) Program
Continuation Power Flow (CPF) program implements the continuation power flow
solver and plots the PV curve as well as the prediction-correction trajectory.
Book “Computational Methods for Electric Power Systems” authored by Mariesa
Crow is referenced during implementation of the programs, and the notations are in
accordance with those in the book.
Please note that execution of the program requires the MATPOWER package is
included in the searching path of MATLAB environment.
The author would like to thank Fangxing Li for his help in developing the program.
One of his courses taught at the University of Tennessee, Knoxville, “Computational
Methods for Power System Analysis”, has been a valuable source.
1.1. Features
Obtain the PV curve through simulation employing prediction-correction
(predictor/corrector) method
The PV curve as well as the prediction-correction trajectory could be plotted
PV curve of every bus is available for plotting
Load at (or near) the nose point of the PV curve, i.e., maximum load value, is
obtained
Simulation step-sizes for voltage predictor/corrector and lambda
predictor/corrector could be specified by users to seek balance between running
time and accuracy
Tested on a given 6 bus system, and the 30 bus system included in MATPOWER
Source codes are self-explanatory
Sufficient comments are provided in the source codes
1.2. Limitations
Sparse matrix techniques have not been employed
Presently CPF with respect to load at only one bus is supported. It could be easily
extended to load change at multiple buses
Presently no more than one generator at each bus is assumed. It could be extended
to support multiple generators at one bus with moderate coding
Screen printouts are not very nicely formatted just for simplicity
Enforcement of generator Q limit is not considered. It could be implemented with
'ENFORCE_Q_LIMS' option in MATPOWER power flow solver.
It is not fully tested for the case with inconsecutive bus numbering
1.3. Demonstration
Running ‘test_cpf.m’ will generate the following outputs. The test case is a 30 bus
case included in MATPOWER package. The PV curve with respect to load at bus 7 is
plotted by the CPF program as follows.
