Security Analysis Server

Description

The security-analysis-server is a microservice of the GridSuite platform dedicated to power network security analysis computation.

Security analysis evaluates the impact of a set of contingencies (network element outages) on a power system. It simulates each contingency and detects any resulting limit violations (current, voltage, active power), assessing whether the network can safely withstand those events.

It provides the following capabilities:

• Run security analysis computations on a network using configurable providers (OpenLoadFlow, DynaFlow).
• N result: detect and store limit violations on the base case (no contingency applied), with filtering, sorting and CSV export.
• N-k contingencies result: for each contingency, report the computation status and the list of limit violations triggered, with filtering, pagination, sorting and CSV export.
• N-k constraints result: group results by constrained equipment (subject), listing all contingencies that cause a violation on it, with filtering, pagination, sorting and CSV export.
• N-k cut-off power result: report connectivity impacts — buses and loads disconnected as a consequence of each contingency — with filtering, pagination and CSV export.
• Manage parameter sets (create, read, update, duplicate, delete) with provider-aware limit reduction configurations per voltage level and limit duration.
• Run computations either synchronously (direct response) or asynchronously (via a RabbitMQ message queue).

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Technical Stack

• Spring Boot (Web, Data JPA, Actuator, Cloud Stream)
• PostgreSQL
• Liquibase
• RabbitMQ via Spring Cloud Stream
• API documentation: OpenAPI / Swagger (springdoc)
• Micrometer / Prometheus
• gridsuite-computation

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Development Scripts

Build Docker image

mvn install -DskipTests -Dpowsybl.docker.install

Please read liquibase usage for instructions to automatically generate changesets. After you generated a changeset do not forget to add it to git and in src/main/resources/db/changelog/db.changelog-master.yml.

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Interactions with Other Microservices

┌───────────────────────────────┐
│  security-analysis-server     │──► network-store-server  (read network topology)
│                               │──► filter-server          (resolve equipment filters for limit violations)
│                               │──► actions-server         (resolve contingency lists)
│                               │──► loadflow-server        (fetch load flow parameters)
│                               │──► report-server          (post computation functional logs)
└───────────────────────────────┘
          ▲  ▼
       RabbitMQ (sa.run / sa.cancel / sa.result / sa.stopped / sa.cancelfailed)

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Asynchronous Execution Flow

1. The controller publishes a message on the sa.run queue.
2. Parallel consumers (consumeRun1, consumeRun2) process messages concurrently for load balancing.
3. The computation result is published on sa.result.
4. Cancellation of a running computation goes through the sa.cancel queue.
5. Dead-letter queues (sa.run.dlx) and quorum queues ensure reliability.

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Result Data

A security analysis result is composed of several complementary datasets exposed through the REST API:

Dataset	Description
N result	Limit violations on the base case (pre-contingency state): subject equipment, violation type, value, limit, side. Supports column filters, global filters (network-element-based), sorting and CSV export.
N-k contingencies result	Per-contingency results: computation status, list of limit violations triggered. Supports column filters, global filters, pagination, sorting and CSV export.
N-k constraints result	Results grouped by constrained equipment: for each subject, the list of contingencies causing a violation. Supports column filters, global filters, pagination, sorting and CSV export.
N-k cut-off power result	Connectivity impacts: buses and loads disconnected following each contingency. Supports column filters, global filters, pagination and CSV export.

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Parameters and Limit Reductions

Security analysis parameters include:

• Provider selection (OpenLoadFlow, DynaFlow).
• Contingency lists: one or more lists of contingencies to simulate, resolved at runtime via the actions-server.
• Limit reductions: a matrix of reduction factors applied to thermal limits before violation detection, configurable per voltage level (nominal voltage range) and per limit duration (TATL duration ranges). Default values are defined in application.yaml.

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Built on gridsuite-computation

The following capabilities are provided by the gridsuite-computation shared library:

• asynchronous run/cancel pipeline,
• transactional result notifications,
• network equipment filtering,
• report integration,
• Micrometer observability.

The security-analysis-server itself focuses on security-analysis-specific logic (parameters, contingency resolution, result model, providers) and delegates the common computation infrastructure to this lib.

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Useful Links

You can find information on OpenLoadFlow here and on DynaFlow here```