Matpower: export considering different nominal voltage

matpower/matpower-converter/src/main/java/com/powsybl/matpower/converter/MatpowerExporter.java

@@ -14,6 +14,8 @@
 import com.powsybl.iidm.network.extensions.SlackTerminal;
 import com.powsybl.iidm.network.util.HvdcUtils;
 import com.powsybl.matpower.model.*;
+
+import org.apache.commons.math3.complex.Complex;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -200,20 +202,7 @@ private void createLines(Network network, MatpowerModel model, Context context)
         for (Line l : network.getLines()) {
             Terminal t1 = l.getTerminal1();
             Terminal t2 = l.getTerminal2();
-            Bus bus1 = t1.getBusView().getBus();
-            Bus bus2 = t2.getBusView().getBus();
-            if (isConnectedToMainCc(bus1) && isConnectedToMainCc(bus2)) {
-                VoltageLevel vl2 = t2.getVoltageLevel();
-                MBranch mBranch = new MBranch();
-                mBranch.setFrom(context.mBusesNumbersByIds.get(bus1.getId()));
-                mBranch.setTo(context.mBusesNumbersByIds.get(bus2.getId()));
-                mBranch.setStatus(CONNECTED_STATUS);
-                double zb = vl2.getNominalV() * vl2.getNominalV() / BASE_MVA;
-                mBranch.setR(l.getR() / zb);
-                mBranch.setX(l.getX() / zb);
-                mBranch.setB((l.getB1() + l.getB2()) * zb);
-                model.addBranch(mBranch);
-            }
+            createMBranch(t1, t2, l.getR(), l.getX(), l.getB1(), l.getB2(), context).ifPresent(model::addBranch);
         }
     }
 
@@ -249,23 +238,54 @@ private void createTieLines(Network network, MatpowerModel model, Context contex
         for (TieLine l : network.getTieLines()) {
             Terminal t1 = l.getDanglingLine1().getTerminal();
             Terminal t2 = l.getDanglingLine2().getTerminal();
-            Bus bus1 = t1.getBusView().getBus();
-            Bus bus2 = t2.getBusView().getBus();
-            if (isConnectedToMainCc(bus1) && isConnectedToMainCc(bus2)) {
-                VoltageLevel vl2 = t2.getVoltageLevel();
-                MBranch mBranch = new MBranch();
-                mBranch.setFrom(context.mBusesNumbersByIds.get(bus1.getId()));
-                mBranch.setTo(context.mBusesNumbersByIds.get(bus2.getId()));
-                mBranch.setStatus(CONNECTED_STATUS);
-                double zb = vl2.getNominalV() * vl2.getNominalV() / BASE_MVA;
-                mBranch.setR(l.getR() / zb);
-                mBranch.setX(l.getX() / zb);
-                mBranch.setB((l.getB1() + l.getB2()) * zb);
-                model.addBranch(mBranch);
-            }
+            createMBranch(t1, t2, l.getR(), l.getX(), l.getB1(), l.getB2(), context).ifPresent(model::addBranch);
+        }
+    }
+
+    private static Optional<MBranch> createMBranch(Terminal t1, Terminal t2, double r, double x, double b1, double b2, Context context) {
+        Bus bus1 = t1.getBusView().getBus();
+        Bus bus2 = t2.getBusView().getBus();
+        if (isConnectedToMainCc(bus1) && isConnectedToMainCc(bus2)) {
+            VoltageLevel vl1 = t1.getVoltageLevel();
+            VoltageLevel vl2 = t2.getVoltageLevel();
+            MBranch mBranch = new MBranch();
+            mBranch.setFrom(context.mBusesNumbersByIds.get(bus1.getId()));
+            mBranch.setTo(context.mBusesNumbersByIds.get(bus2.getId()));
+            mBranch.setStatus(CONNECTED_STATUS);
+
+            double rpu = impedanceToPerUnitForLine(r, vl1.getNominalV(), vl2.getNominalV(), BASE_MVA);
+            double xpu = impedanceToPerUnitForLine(x, vl1.getNominalV(), vl2.getNominalV(), BASE_MVA);
+            Complex ytr = impedanceToAdmittance(r, x);
+            double b1pu = admittanceEndToPerUnitForLine(ytr.getImaginary(), b1, vl1.getNominalV(), vl2.getNominalV(), BASE_MVA);
+            double b2pu = admittanceEndToPerUnitForLine(ytr.getImaginary(), b2, vl2.getNominalV(), vl1.getNominalV(), BASE_MVA);
+            mBranch.setR(rpu);
+            mBranch.setX(xpu);
+            mBranch.setB(b1pu + b2pu);
+            return Optional.of(mBranch);
+        } else {
+            return Optional.empty();
         }
     }
 
+    // avoid NaN when r and x, both are 0.0
+    private static Complex impedanceToAdmittance(double r, double x) {
+        return r == 0.0 && x == 0.0 ? new Complex(0.0, 0.0) : new Complex(r, x).reciprocal();
+    }
+
+    private static double impedanceToPerUnitForLine(double impedance, double nominalVoltageAtEnd,
+        double nominalVoltageAtOtherEnd, double sBase) {
+        // this method handles also line with different nominal voltage at ends
+        return impedance * sBase / (nominalVoltageAtEnd * nominalVoltageAtOtherEnd);
+    }
+
+    private static double admittanceEndToPerUnitForLine(double transmissionAdmittance, double shuntAdmittanceAtEnd,
+        double nominalVoltageAtEnd, double nominalVoltageAtOtherEnd, double sBase) {
+        // this method handles also line with different nominal voltage at ends
+        // note that ytr is in engineering units
+        return (shuntAdmittanceAtEnd * nominalVoltageAtEnd * nominalVoltageAtEnd
+            + (nominalVoltageAtEnd - nominalVoltageAtOtherEnd) * nominalVoltageAtEnd * transmissionAdmittance) / sBase;
+    }
+
     private void createDanglingLineBranches(Network network, MatpowerModel model, Context context) {
         for (DanglingLine dl : network.getDanglingLines(DanglingLineFilter.UNPAIRED)) {
             Terminal t = dl.getTerminal();

matpower/matpower-converter/src/test/java/com/powsybl/matpower/converter/MatpowerExporterTest.java

@@ -9,25 +9,33 @@
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.io.ByteStreams;
 import com.powsybl.cgmes.conformity.CgmesConformity1ModifiedCatalog;
+import com.powsybl.commons.datasource.FileDataSource;
 import com.powsybl.commons.datasource.MemDataSource;
+import com.powsybl.commons.test.AbstractConverterTest;
 import com.powsybl.iidm.network.Network;
+import com.powsybl.iidm.network.NetworkFactory;
 import com.powsybl.iidm.network.test.EurostagTutorialExample1Factory;
 import com.powsybl.iidm.network.test.FourSubstationsNodeBreakerFactory;
 import com.powsybl.matpower.model.MatpowerModel;
+import com.powsybl.matpower.model.MatpowerModelFactory;
 import com.powsybl.matpower.model.MatpowerReader;
+import com.powsybl.matpower.model.MatpowerWriter;
+
 import org.junit.jupiter.api.Test;
 
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
+import java.nio.file.Path;
 import java.util.Objects;
+import java.util.Properties;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
 /**
  * @author Geoffroy Jamgotchian <geoffroy.jamgotchian at rte-france.com>
  */
-class MatpowerExporterTest {
+class MatpowerExporterTest extends AbstractConverterTest {
 
     private static void exportToMatAndCompareTo(Network network, String refJsonFile) throws IOException {
         MemDataSource dataSource = new MemDataSource();
@@ -64,4 +72,19 @@ void testWithHvdcLines() throws IOException {
         var network = FourSubstationsNodeBreakerFactory.create();
         exportToMatAndCompareTo(network, "/fourSubstationFactory.json");
     }
+
+    @Test
+    void testCase30ConsideringBaseVoltage() throws IOException {
+        MatpowerModel model = MatpowerModelFactory.create30();
+        model.setCaseName("ieee30-considering-base-voltage");
+        String caseId = model.getCaseName();
+        Path matFile = tmpDir.resolve(caseId + ".mat");
+        MatpowerWriter.write(model, matFile);
+
+        Properties properties = new Properties();
+        properties.put("matpower.import.ignore-base-voltage", false);
+        Network network = new MatpowerImporter().importData(new FileDataSource(tmpDir, caseId), NetworkFactory.findDefault(), properties);
+
+        exportToMatAndCompareTo(network, "/ieee30-considering-base-voltage.json");
+    }
 }

matpower/matpower-converter/src/test/resources/be.json

@@ -231,7 +231,7 @@
   "branches" : [ {
     "from" : 5,
     "to" : 4,
-    "r" : 0.0038222222222222225,
+    "r" : 0.003822222222222222,
     "x" : 0.06755555555555556,
     "b" : 0.021470821875,
     "rateA" : 0.0,
@@ -245,9 +245,9 @@
   }, {
     "from" : 5,
     "to" : 4,
-    "r" : 0.010277530864197531,
+    "r" : 0.010277530864197533,
     "x" : 0.1402469135802469,
-    "b" : 0.010131024375,
+    "b" : 0.010131024374999999,
     "rateA" : 0.0,
     "rateB" : 0.0,
     "rateC" : 0.0,