{
  "$schema": "https://ps-wiki.github.io/schema/v1/term.schema.json",
  "id": "composite-short-circuit-ratio",
  "title": "Composite Short-Circuit Ratio",
  "description": "CSCR. The equivalent system impedance seen by multiple inverter-based resources by creating a common medium voltage bus and tying all inverter-based resources of interest together at that common bus.",
  "language": "en",
  "tags": [
    "stability",
    "nerc"
  ],
  "related": [
    "grid-strength",
    "stability",
    "short-circuit-ratio",
    "weighted-short-circuit-ratio",
    "short-circuit-ratio-with-interaction-factors",
    "generalized-short-circuit-ratio"
  ],
  "breaking": false,
  "dates": {
    "created": "2025-11-29",
    "last_modified": "2025-11-29"
  },
  "authors": [
    {
      "name": "Jinning Wang",
      "url": "https://jinningwang.github.io"
    }
  ],
  "content": {
    "sections": [
      {
        "order": 1,
        "id": "definition-in-an-article",
        "title": "Definition in an Article",
        "type": "definition",
        "source_keys": [
          "nerc2017integrating"
        ],
        "page": "p2",
        "body_md": "> Composite short circuit ratio (CSCR) estimates the equivalent system impedance seen by multiple inverter-based resources by creating a common medium voltage bus and tying all inverter-based resources of interest together at that common bus. The composite short circuit MVA at the common bus without current contribution from the inverter-based resources, $CSC_{MVA}$, is then calculated. CSCR can then be calculated as\n>\n> $CSCR = \\frac{CSC_{MVA}}{MW_{VER}}$\n>\n> where $MW_{VER}$ is the sum of the nominal power rating of all inverter-based resources considered. This method calculates an aggregate SCR for multiple inverter-based resources, rather than each resource like the conventional SCR approach.\n"
      }
    ]
  }
}