ShuntFortescueIxEquationTerm.java
/**
* Copyright (c) 2023, Jean-Baptiste Heyberger <jbheyberger at gmail.com>
* Copyright (c) 2023, Geoffroy Jamgotchian <geoffroy.jamgotchian at gmail.com>
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
* SPDX-License-Identifier: MPL-2.0
*/
package com.powsybl.openloadflow.ac.equations.asym;
import com.powsybl.openloadflow.ac.equations.AcVariableType;
import com.powsybl.openloadflow.equations.Variable;
import com.powsybl.openloadflow.equations.VariableSet;
import com.powsybl.openloadflow.network.LfBus;
import com.powsybl.openloadflow.util.Fortescue;
import net.jafama.FastMath;
import java.util.Objects;
/**
* @author Jean-Baptiste Heyberger {@literal <jbheyberger at gmail.com>}
*/
public class ShuntFortescueIxEquationTerm extends AbstractShuntFortescueCurrentEquationTerm {
public ShuntFortescueIxEquationTerm(LfBus bus, VariableSet<AcVariableType> variableSet, Fortescue.SequenceType sequenceType) {
super(bus, variableSet, sequenceType);
}
/**
* By definition:
* I is the current flowing out of the node in the shunt equipment
* I = y.V with y = g+jb
* Therefore Ix + jIy = g.Vx - b.Vy + j(g.Vy + b.Vx)
* then Ix = g.Vmagnitude.cos(theta) - b.Vmagnitude.sin(theta)
*/
private static double ix(double v, double phi, double g, double b) {
return g * v * FastMath.cos(phi) - b * v * FastMath.sin(phi);
}
private static double dixdv(double phi, double g, double b) {
return g * FastMath.cos(phi) - b * FastMath.sin(phi);
}
private static double dixdph(double v, double phi, double g, double b) {
return -g * v * FastMath.sin(phi) - b * v * FastMath.cos(phi);
}
@Override
public double eval() {
return ix(v(), ph(), g(), b());
}
@Override
public double der(Variable<AcVariableType> variable) {
Objects.requireNonNull(variable);
if (variable.equals(vVar)) {
return dixdv(ph(), g(), b());
} else if (variable.equals(phVar)) {
return dixdph(v(), ph(), g(), b());
} else {
throw new IllegalStateException("Unknown variable: " + variable);
}
}
@Override
public String getName() {
return "ac_ix_fortescue_shunt";
}
}