nme_xfmr3p.m

classdef nme_xfmr3p < mp.nm_element & mp.form_acp
% mp.nme_xfmr3p - Network model element for 3-phase transformer.
%
% Implements the network model element for 3-phase transformer elements,
% with 6 ports per transformer.
%
% Implements building of the admittance parameter :math:`\YY` for 3-phase
% transformers and inherits from mp.form_acp.

%   MATPOWER
%   Copyright (c) 2021-2024, Power Systems Engineering Research Center (PSERC)
%   by Ray Zimmerman, PSERC Cornell
%
%   This file is part of MATPOWER.
%   Covered by the 3-clause BSD License (see LICENSE file for details).
%   See https://matpower.org for more info.

%     properties
%     end     %% properties

    methods
        function name = name(obj)
            %
            name = 'xfmr3p';
        end

        function np = np(obj)
            %
            np = 6;     %% this is a 6 port element
        end

        function obj = build_params(obj, nm, dm)
            %
            build_params@mp.nm_element(obj, nm, dm);    %% call parent

            dme = obj.data_model_element(dm);
            bus_dme = dm.elements.(dme.cxn_type);
            nk = 3*obj.nk;

            base_kv = bus_dme.tab.base_kv(bus_dme.on(dme.fbus(dme.on)));
            z = dm.base_kva * (dme.r + 1j * dme.x) ./ dme.base_kva .* ...
                (dme.base_kv ./ ( base_kv / sqrt(3))) .^ 2;
            y = 1 ./ z;
            Y = [y;y;y];

            obj.Y = sparse( ...
                [1:nk 1:nk nk+1:2*nk nk+1:2*nk]', ...
                [1:nk nk+1:2*nk 1:nk nk+1:2*nk]', ...
                [Y; -Y; -Y; Y], 2*nk, 2*nk );
        end
    end     %% methods
end         %% classdef