CPF_P Computes the value of the CPF parameterization function. P = CPF_P(PARAMETERIZATION, STEP, Z, V, LAM, VPRV, LAMPRV, PV, PQ) Computes the value of the parameterization function at the current solution point. Inputs: PARAMETERIZATION : Value of cpf.parameterization option STEP : continuation step size Z : normalized tangent prediction vector from previous step V : complex bus voltage vector at current solution LAM : scalar lambda value at current solution VPRV : complex bus voltage vector at previous solution LAMPRV : scalar lambda value at previous solution PV : vector of indices of PV buses PQ : vector of indices of PQ buses Outputs: P : value of the parameterization function at the current point See also CPF_PREDICTOR, CPF_CORRECTOR.
0001 function P = cpf_p(parameterization, step, z, V, lam, Vprv, lamprv, pv, pq) 0002 %CPF_P Computes the value of the CPF parameterization function. 0003 % 0004 % P = CPF_P(PARAMETERIZATION, STEP, Z, V, LAM, VPRV, LAMPRV, PV, PQ) 0005 % 0006 % Computes the value of the parameterization function at the current 0007 % solution point. 0008 % 0009 % Inputs: 0010 % PARAMETERIZATION : Value of cpf.parameterization option 0011 % STEP : continuation step size 0012 % Z : normalized tangent prediction vector from previous step 0013 % V : complex bus voltage vector at current solution 0014 % LAM : scalar lambda value at current solution 0015 % VPRV : complex bus voltage vector at previous solution 0016 % LAMPRV : scalar lambda value at previous solution 0017 % PV : vector of indices of PV buses 0018 % PQ : vector of indices of PQ buses 0019 % 0020 % Outputs: 0021 % P : value of the parameterization function at the current point 0022 % 0023 % See also CPF_PREDICTOR, CPF_CORRECTOR. 0024 0025 % MATPOWER 0026 % Copyright (c) 1996-2015 by Power System Engineering Research Center (PSERC) 0027 % by Shrirang Abhyankar, Argonne National Laboratory 0028 % and Ray Zimmerman, PSERC Cornell 0029 % 0030 % $Id: cpf_p.m 2644 2015-03-11 19:34:22Z ray $ 0031 % 0032 % This file is part of MATPOWER. 0033 % Covered by the 3-clause BSD License (see LICENSE file for details). 0034 % See http://www.pserc.cornell.edu/matpower/ for more info. 0035 0036 %% evaluate P(x0, lambda0) 0037 if parameterization == 1 %% natural 0038 if lam >= lamprv 0039 P = lam - lamprv - step; 0040 else 0041 P = lamprv - lam - step; 0042 end 0043 elseif parameterization == 2 %% arc length 0044 Va = angle(V); 0045 Vm = abs(V); 0046 Vaprv = angle(Vprv); 0047 Vmprv = abs(Vprv); 0048 P = sum(([Va([pv; pq]); Vm(pq); lam] - [Vaprv([pv; pq]); Vmprv(pq); lamprv]).^2) - step^2; 0049 elseif parameterization == 3 %% pseudo arc length 0050 nb = length(V); 0051 Va = angle(V); 0052 Vm = abs(V); 0053 Vaprv = angle(Vprv); 0054 Vmprv = abs(Vprv); 0055 P = z([pv; pq; nb+pq; 2*nb+1])' * ... 0056 ( [Va([pv; pq]); Vm(pq); lam] - [Vaprv([pv; pq]); Vmprv(pq); lamprv] )... 0057 - step; 0058 end