Draft : SA : output a result for contingencies with no impact

src/main/java/com/powsybl/openloadflow/network/impl/PropagatedContingency.java

@@ -441,15 +441,25 @@ private static boolean isConnectedAfterContingencySide2(Map<LfBranch, DisabledBr
  return status == null || status == DisabledBranchStatus.SIDE_1;
  }
 
+ public enum ToLfContingencyConversionStatus {
+ OK,
+ ISOLATED_SLACK_BUS,
+ NO_IMPACT;
+ }
+
  public Optional<LfContingency> toLfContingency(LfNetwork network) {
+ return toLfContingencyWithStatus(network).getKey();
+ }
+
+ public Pair<Optional<LfContingency>, ToLfContingencyConversionStatus> toLfContingencyWithStatus(LfNetwork network) {
  // find branch to open because of direct impact of the contingency (including propagation is activated)
  Map<LfBranch, DisabledBranchStatus> branchesToOpen = findBranchToOpenDirectlyImpactedByContingency(network);
 
  // find branches to open and buses to lost not directly from the contingency impact but as a consequence of
  // loss of connectivity once contingency applied on the network
  ContingencyConnectivityLossImpact connectivityLossImpact = findBusesAndBranchesImpactedBecauseOfConnectivityLoss(network, branchesToOpen);
  if (!connectivityLossImpact.ok) {
- return Optional.empty();
+ return Pair.of(Optional.empty(), ToLfContingencyConversionStatus.ISOLATED_SLACK_BUS);
  }
  Set<LfBus> busesToLost = connectivityLossImpact.busesToLost(); // nothing else
 
@@ -521,11 +531,10 @@ public Optional<LfContingency> toLfContingency(LfNetwork network) {
  && lostHvdcs.isEmpty()
  && connectivityLossImpact.hvdcsWithoutPower().isEmpty()) {
  LOGGER.debug("Contingency '{}' has no impact", contingency.getId());
- return Optional.empty();
+ return Pair.of(Optional.empty(), ToLfContingencyConversionStatus.NO_IMPACT);
  }
-
- return Optional.of(new LfContingency(contingency.getId(), index, connectivityLossImpact.createdSynchronousComponents,
+ return Pair.of(Optional.of(new LfContingency(contingency.getId(), index, connectivityLossImpact.createdSynchronousComponents,
  new DisabledNetwork(busesToLost, branchesToOpen, lostHvdcs), shunts, loads, generators,
- connectivityLossImpact.hvdcsWithoutPower()));
+ connectivityLossImpact.hvdcsWithoutPower())), ToLfContingencyConversionStatus.OK);
  }
 }

src/main/java/com/powsybl/openloadflow/sa/AbstractSecurityAnalysis.java

@@ -437,53 +437,65 @@ protected SecurityAnalysisResult runSimulations(LfNetwork lfNetwork, List<Propag
  Iterator<PropagatedContingency> contingencyIt = propagatedContingencies.iterator();
  while (contingencyIt.hasNext() && !Thread.currentThread().isInterrupted()) {
  PropagatedContingency propagatedContingency = contingencyIt.next();
- propagatedContingency.toLfContingency(lfNetwork)
- .ifPresent(lfContingency -> { // only process contingencies that impact the network
- ReportNode postContSimReportNode = Reports.createPostContingencySimulation(networkReportNode, lfContingency.getId());
- lfNetwork.setReportNode(postContSimReportNode);
-
- lfContingency.apply(loadFlowParameters.getBalanceType());
-
- distributedMismatch(lfNetwork, lfContingency.getActivePowerLoss(), loadFlowParameters, openLoadFlowParameters);
-
- var postContingencyResult = runPostContingencySimulation(lfNetwork, context, propagatedContingency.getContingency(),
- lfContingency, preContingencyLimitViolationManager,
- securityAnalysisParameters.getIncreasedViolationsParameters(),
- preContingencyNetworkResult, createResultExtension);
- postContingencyResults.add(postContingencyResult);
-
- List<OperatorStrategy> operatorStrategiesForThisContingency = operatorStrategiesByContingencyId.get(lfContingency.getId());
- if (operatorStrategiesForThisContingency != null) {
- // we have at least an operator strategy for this contingency.
- if (operatorStrategiesForThisContingency.size() == 1) {
- runActionSimulation(lfNetwork, context,
- operatorStrategiesForThisContingency.get(0), preContingencyLimitViolationManager,
- securityAnalysisParameters.getIncreasedViolationsParameters(), lfActionById,
- createResultExtension, lfContingency, postContingencyResult.getLimitViolationsResult(),
- acParameters.getNetworkParameters())
- .ifPresent(operatorStrategyResults::add);
- } else {
- // save post contingency state for later restoration after action
- NetworkState postContingencyNetworkState = NetworkState.save(lfNetwork);
- for (OperatorStrategy operatorStrategy : operatorStrategiesForThisContingency) {
- runActionSimulation(lfNetwork, context,
- operatorStrategy, preContingencyLimitViolationManager,
- securityAnalysisParameters.getIncreasedViolationsParameters(), lfActionById,
- createResultExtension, lfContingency, postContingencyResult.getLimitViolationsResult(),
- acParameters.getNetworkParameters())
- .ifPresent(result -> {
- operatorStrategyResults.add(result);
- postContingencyNetworkState.restore();
- });
+
+ var lfContingencyWithStatus = propagatedContingency.toLfContingencyWithStatus(lfNetwork);
+
+ switch (lfContingencyWithStatus.getRight()) {
+ case ISOLATED_SLACK_BUS:
+ break;
+ case NO_IMPACT:
+ postContingencyResults.add(new PostContingencyResult(propagatedContingency.getContingency(), PostContingencyComputationStatus.NO_IMPACT, new ArrayList<>()));
+ break;
+ case OK:
+ propagatedContingency.toLfContingency(lfNetwork)
+ .ifPresent(lfContingency -> { // only process contingencies that impact the network
+ ReportNode postContSimReportNode = Reports.createPostContingencySimulation(networkReportNode, lfContingency.getId());
+ lfNetwork.setReportNode(postContSimReportNode);
+
+ lfContingency.apply(loadFlowParameters.getBalanceType());
+
+ distributedMismatch(lfNetwork, lfContingency.getActivePowerLoss(), loadFlowParameters, openLoadFlowParameters);
+
+ var postContingencyResult = runPostContingencySimulation(lfNetwork, context, propagatedContingency.getContingency(),
+ lfContingency, preContingencyLimitViolationManager,
+ securityAnalysisParameters.getIncreasedViolationsParameters(),
+ preContingencyNetworkResult, createResultExtension);
+ postContingencyResults.add(postContingencyResult);
+
+ List<OperatorStrategy> operatorStrategiesForThisContingency = operatorStrategiesByContingencyId.get(lfContingency.getId());
+ if (operatorStrategiesForThisContingency != null) {
+ // we have at least an operator strategy for this contingency.
+ if (operatorStrategiesForThisContingency.size() == 1) {
+ runActionSimulation(lfNetwork, context,
+ operatorStrategiesForThisContingency.get(0), preContingencyLimitViolationManager,
+ securityAnalysisParameters.getIncreasedViolationsParameters(), lfActionById,
+ createResultExtension, lfContingency, postContingencyResult.getLimitViolationsResult(),
+ acParameters.getNetworkParameters())
+ .ifPresent(operatorStrategyResults::add);
+ } else {
+ // save post contingency state for later restoration after action
+ NetworkState postContingencyNetworkState = NetworkState.save(lfNetwork);
+ for (OperatorStrategy operatorStrategy : operatorStrategiesForThisContingency) {
+ runActionSimulation(lfNetwork, context,
+ operatorStrategy, preContingencyLimitViolationManager,
+ securityAnalysisParameters.getIncreasedViolationsParameters(), lfActionById,
+ createResultExtension, lfContingency, postContingencyResult.getLimitViolationsResult(),
+ acParameters.getNetworkParameters())
+ .ifPresent(result -> {
+ operatorStrategyResults.add(result);
+ postContingencyNetworkState.restore();
+ });
+ }
+ }
+ }
+
+ if (contingencyIt.hasNext()) {
+ // restore base state
+ networkState.restore();
  }
- }
- }
-
- if (contingencyIt.hasNext()) {
- // restore base state
- networkState.restore();
- }
- });
+ });
+ break;
+ }
  }
  }
 

src/main/java/com/powsybl/openloadflow/sensi/AcSensitivityAnalysis.java

@@ -340,7 +340,7 @@ public void analyse(Network network, List<PropagatedContingency> contingencies,
  }
  networkState.restore();
  }, () -> {
- // it means that the contingency has no impact.
+ // it means that the contingency has no impact or leads to an isolated slack bus
  // we need to force the state vector to be re-initialized from base case network state
  AcSolverUtil.initStateVector(lfNetwork, context.getEquationSystem(), context.getParameters().getVoltageInitializer());
 

src/test/java/com/powsybl/openloadflow/sa/OpenSecurityAnalysisTest.java

@@ -1053,8 +1053,8 @@ void testSaWithDisconnectedLoadContingency() {
 
  SecurityAnalysisResult result = runSecurityAnalysis(network, contingencies);
 
- // load is disconnected, contingency is skipped
- assertFalse(getOptionalPostContingencyResult(result, "l2").isPresent());
+ // load is disconnected, contingency has no impact
+ assertEquals(PostContingencyComputationStatus.NO_IMPACT, getPostContingencyResult(result, "l2").getStatus());
  }
 
  @Test