Fix fork disconnection (#3245)

Signed-off-by: Nicolas Rol <[email protected]>
(cherry picked from commit f0482f1)

iidm/iidm-impl/src/main/java/com/powsybl/iidm/network/impl/NodeBreakerTopologyModel.java

@@ -1285,8 +1285,8 @@ boolean getDisconnectingSwitches(Terminal terminal, Predicate<? super SwitchImpl
         checkTopologyKind(terminal);
 
         int node = ((NodeTerminal) terminal).getNode();
-        // find all paths starting from the current terminal to a busbar section that does not contain an open switch
-        List<TIntArrayList> paths = graph.findAllPaths(node, NodeBreakerTopologyModel::isBusbarSection, SwitchPredicates.IS_OPEN);
+        // find all paths starting from the current terminal to a terminal that does not contain an open switch
+        List<TIntArrayList> paths = graph.findAllPaths(node, Objects::nonNull, SwitchPredicates.IS_OPEN);
         if (paths.isEmpty()) {
             return false;
         }

iidm/iidm-impl/src/test/java/com/powsybl/iidm/network/impl/tck/ForkConnectDisconnectTest.java

@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2024, RTE (http://www.rte-france.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.iidm.network.impl.tck;
+
+import com.powsybl.iidm.network.tck.AbstractForkConnectDisconnectTest;
+
+/**
+ * @author Nicolas Rol {@literal <nicolas.rol at rte-france.com>}
+ */
+class ForkConnectDisconnectTest extends AbstractForkConnectDisconnectTest {
+}

iidm/iidm-tck/src/test/java/com/powsybl/iidm/network/tck/AbstractForkConnectDisconnectTest.java

@@ -0,0 +1,247 @@
+/*
+ * Copyright (c) 2024, RTE (http://www.rte-france.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.iidm.network.tck;
+
+import com.powsybl.iidm.network.*;
+import com.powsybl.iidm.network.extensions.BusbarSectionPositionAdder;
+import com.powsybl.iidm.network.util.SwitchPredicates;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
+/**
+ * @author Nicolas Rol {@literal <nicolas.rol at rte-france.com>}
+ */
+public abstract class AbstractForkConnectDisconnectTest {
+
+    public Network createNetwork() {
+        Network network = Network.create("test", "test");
+        // Substations
+        Substation s1 = network.newSubstation()
+            .setId("S1")
+            .setCountry(Country.FR)
+            .add();
+        VoltageLevel vl1 = s1.newVoltageLevel()
+            .setId("VL1")
+            .setNominalV(1.0)
+            .setTopologyKind(TopologyKind.NODE_BREAKER)
+            .add();
+        VoltageLevel vl2 = s1.newVoltageLevel()
+            .setId("VL2")
+            .setNominalV(1.0)
+            .setTopologyKind(TopologyKind.NODE_BREAKER)
+            .add();
+
+        // Busbar sections
+        BusbarSection bbs1 = vl1.getNodeBreakerView()
+            .newBusbarSection()
+            .setId("BBS11")
+            .setNode(0)
+            .add();
+        bbs1.newExtension(BusbarSectionPositionAdder.class)
+            .withBusbarIndex(1)
+            .withSectionIndex(1)
+            .add();
+        BusbarSection bbs2A = vl2.getNodeBreakerView()
+            .newBusbarSection()
+            .setId("BBS2A")
+            .setNode(0)
+            .add();
+        bbs2A.newExtension(BusbarSectionPositionAdder.class)
+            .withBusbarIndex(1)
+            .withSectionIndex(1)
+            .add();
+        BusbarSection bbs2B = vl2.getNodeBreakerView()
+            .newBusbarSection()
+            .setId("BBS2B")
+            .setNode(1)
+            .add();
+        bbs2B.newExtension(BusbarSectionPositionAdder.class)
+            .withBusbarIndex(2)
+            .withSectionIndex(1)
+            .add();
+
+        // Lines
+        network.newLine()
+            .setId("L1")
+            .setName("LINE1")
+            .setR(1.0)
+            .setX(2.0)
+            .setG1(3.0)
+            .setG2(3.5)
+            .setB1(4.0)
+            .setB2(4.5)
+            .setVoltageLevel1("VL1")
+            .setVoltageLevel2("VL2")
+            .setNode1(4)
+            .setNode2(3)
+            .add();
+
+        // Add a second line
+        network.newLine()
+            .setId("L2")
+            .setName("LINE2")
+            .setR(1.0)
+            .setX(2.0)
+            .setG1(3.0)
+            .setG2(3.5)
+            .setB1(4.0)
+            .setB2(4.5)
+            .setVoltageLevel1("VL1")
+            .setVoltageLevel2("VL2")
+            .setNode1(5)
+            .setNode2(5)
+            .add();
+
+        // VL1 - Breakers and disconnectors for L1 and L2
+        vl1.getNodeBreakerView().newDisconnector()
+            .setId("D_L1")
+            .setNode1(4)
+            .setNode2(6)
+            .setOpen(false)
+            .add();
+        vl1.getNodeBreakerView().newDisconnector()
+            .setId("D_L2")
+            .setNode1(5)
+            .setNode2(6)
+            .setOpen(false)
+            .add();
+        vl1.getNodeBreakerView().newBreaker()
+            .setId("B_L1_L2")
+            .setNode1(6)
+            .setNode2(7)
+            .setOpen(false)
+            .setFictitious(false)
+            .add();
+        vl1.getNodeBreakerView().newDisconnector()
+            .setId("D0")
+            .setNode1(7)
+            .setNode2(0)
+            .setOpen(false)
+            .add();
+
+        // VL2 - Breakers and disconnectors for L1 and L2
+        vl2.getNodeBreakerView().newBreaker()
+            .setId("B_L1_VL2")
+            .setNode1(3)
+            .setNode2(2)
+            .setOpen(false)
+            .setFictitious(false)
+            .add();
+        vl2.getNodeBreakerView().newDisconnector()
+            .setId("D_L1_BBS2A")
+            .setNode1(2)
+            .setNode2(0)
+            .setOpen(false)
+            .add();
+        vl2.getNodeBreakerView().newDisconnector()
+            .setId("D_L1_BBS2B")
+            .setNode1(2)
+            .setNode2(1)
+            .setOpen(true)
+            .add();
+        vl2.getNodeBreakerView().newBreaker()
+            .setId("B_L2_VL2")
+            .setNode1(5)
+            .setNode2(4)
+            .setOpen(false)
+            .setFictitious(false)
+            .add();
+        vl2.getNodeBreakerView().newDisconnector()
+            .setId("D_L2_BBS2A")
+            .setNode1(4)
+            .setNode2(0)
+            .setOpen(true)
+            .add();
+        vl2.getNodeBreakerView().newDisconnector()
+            .setId("D_L2_BBS2B")
+            .setNode1(4)
+            .setNode2(1)
+            .setOpen(false)
+            .add();
+        return network;
+    }
+
+    @Test
+    public void fullyClosedTest() {
+        Network network = createNetwork();
+
+        // Useful elements
+        VoltageLevel.NodeBreakerView topo = network.getVoltageLevel("VL1").getNodeBreakerView();
+        Line line1 = network.getLine("L1");
+        Line line2 = network.getLine("L2");
+        Switch disconnector = network.getSwitch("D_L1");
+
+        // L1 and L2 are fully connected
+        assertTrue(topo.getOptionalTerminal(4).isPresent());
+        assertTerminalsStatus(line1.getTerminals(), true);
+        assertTrue(topo.getOptionalTerminal(5).isPresent());
+        assertTerminalsStatus(line2.getTerminals(), true);
+
+        // Disconnect L1
+        line1.disconnect(SwitchPredicates.IS_NON_NULL);
+
+        // check that L1 is disconnected while L2 is still connected
+        assertTrue(topo.getOptionalTerminal(4).isPresent());
+        assertTerminalsStatus(line1.getTerminals(), false);
+        assertTrue(topo.getOptionalTerminal(5).isPresent());
+        assertTerminalsStatus(line2.getTerminals(), true);
+
+        // D_L1 should be open
+        assertTrue(disconnector.isOpen());
+    }
+
+    @Test
+    public void forkDisconnectedTest() {
+        Network network = createNetwork();
+
+        // Useful elements
+        VoltageLevel.NodeBreakerView topo = network.getVoltageLevel("VL1").getNodeBreakerView();
+        Line line1 = network.getLine("L1");
+        Line line2 = network.getLine("L2");
+        Switch disconnectorL1 = network.getSwitch("D_L1");
+        Switch disconnectorL2 = network.getSwitch("D_L2");
+        Switch breaker = network.getSwitch("B_L1_L2");
+
+        // In this case, B_L1_L2 is open
+        breaker.setOpen(true);
+
+        // L1 and L2 are fully connected
+        assertTrue(topo.getOptionalTerminal(4).isPresent());
+        assertTerminalsStatus(line1.getTerminals(), true);
+        assertTrue(topo.getOptionalTerminal(5).isPresent());
+        assertTerminalsStatus(line2.getTerminals(), true);
+
+        // Disconnect L1
+        line1.disconnect(SwitchPredicates.IS_NON_NULL);
+
+        // check that L1 and L2 are disconnected
+        assertTrue(topo.getOptionalTerminal(4).isPresent());
+        assertTerminalsStatus(line1.getTerminals(), false);
+        assertTrue(topo.getOptionalTerminal(5).isPresent());
+        assertTerminalsStatus(List.of(line2.getTerminal1()), false);
+        assertTerminalsStatus(List.of(line2.getTerminal2()), true);
+
+        // D_L1 should be open but not D_L2
+        assertTrue(disconnectorL1.isOpen());
+        assertFalse(disconnectorL2.isOpen());
+    }
+
+    private void assertTerminalsStatus(List<? extends Terminal> terminals, boolean terminalsShouldBeConnected) {
+        if (terminalsShouldBeConnected) {
+            terminals.forEach(terminal -> assertNotNull(terminal.getBusView().getBus()));
+            terminals.forEach(terminal -> assertTrue(terminal.isConnected()));
+        } else {
+            terminals.forEach(terminal -> assertNull(terminal.getBusView().getBus()));
+            terminals.forEach(terminal -> assertFalse(terminal.isConnected()));
+        }
+    }
+}