{
  "node": {
    "id": "term:vcu",
    "type": "Term",
    "label": "Vehicle control unit",
    "properties": {
      "id": "vcu",
      "name": "Vehicle control unit",
      "abbr": "VCU",
      "section": "topic-data",
      "definition": "The supervisory controller of an electric vehicle: it interprets the driver’s demand, asks the motor controller for torque and the BMS for the power it may give, and decides when the high-voltage system may switch on. The BMS reports to it, usually over CAN.",
      "related": [
        "bmu",
        "can-bus",
        "state-of-power",
        "inverter",
        "ccu"
      ],
      "url": "https://lemonergy.com/learn/glossary/vcu/",
      "mentions": [
        "bms",
        "electric-vehicle"
      ]
    }
  },
  "edges": [
    {
      "id": "edge:4014",
      "source": "term:vcu",
      "target": "topic:topic-data",
      "type": "belongsTo",
      "properties": {
        "sourceFile": "terms.json"
      }
    },
    {
      "id": "edge:4015",
      "source": "term:vcu",
      "target": "term:bmu",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4016",
      "source": "term:vcu",
      "target": "term:can-bus",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4017",
      "source": "term:vcu",
      "target": "term:state-of-power",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4018",
      "source": "term:vcu",
      "target": "term:inverter",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:4019",
      "source": "term:vcu",
      "target": "term:ccu",
      "type": "relatedTo",
      "properties": {
        "sourceFile": "terms.json",
        "meaning": "Related context; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/vcu/bms",
      "source": "term:vcu",
      "target": "term:bms",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    },
    {
      "id": "edge:mentions/vcu/electric-vehicle",
      "source": "term:vcu",
      "target": "term:electric-vehicle",
      "type": "mentions",
      "properties": {
        "sourceFile": "terms.json",
        "method": "build_glossary.mention_index + mentions",
        "field": "definition",
        "meaning": "Text mention; not a causal claim"
      }
    }
  ],
  "neighbors": [
    {
      "id": "topic:topic-data",
      "type": "Topic",
      "label": "Data, communication and electronics",
      "properties": {
        "id": "topic-data",
        "name": "Data, communication and electronics",
        "lede": "The control units, chips, protocols and file formats through which a battery is measured, controlled and logged.",
        "context": "Separate quantities from encoding and transport.",
        "example": "2500 in a log might mean 25.00 °C, 2.5 V or raw counts. Units and scale must accompany the value.",
        "lesson_url": "https://lemonergy.com/learn/fundamentals/battery-basics/",
        "lesson_label": "Open battery basics"
      }
    },
    {
      "id": "term:bmu",
      "type": "Term",
      "label": "Battery management unit",
      "properties": {
        "id": "bmu",
        "name": "Battery management unit",
        "abbr": "BMU",
        "aka": [
          "BMS master",
          "master BMS"
        ],
        "section": "topic-data",
        "definition": "The master controller of a battery management system: it collects cell voltages and temperatures from the monitoring boards, runs the state estimation and protection logic, drives the contactors and talks to the vehicle. In some architectures the same name is used for a per-module slave, so a datasheet’s block diagram is the safe reference.",
        "related": [
          "bms",
          "cell-supervision-circuit",
          "bcu",
          "contactor",
          "can-bus",
          "bms-power-modes"
        ],
        "url": "https://lemonergy.com/learn/glossary/bmu/",
        "mentions": [
          "datasheet"
        ]
      }
    },
    {
      "id": "term:can-bus",
      "type": "Term",
      "label": "CAN bus",
      "properties": {
        "id": "can-bus",
        "name": "CAN bus",
        "aka": [
          "Controller Area Network",
          "ISO 11898"
        ],
        "section": "topic-pack",
        "definition": "The serial network over which a BMS talks to the vehicle or inverter: a two-wire differential bus, defined in ISO 11898, carrying short prioritised messages at up to 1 Mbit/s, or faster with CAN FD. Every node hears every message, and a dominant bit wins arbitration without any collision.",
        "related": [
          "can-high-low",
          "can-fd",
          "termination-resistor",
          "bms",
          "lin-bus",
          "fms-interface"
        ],
        "url": "https://lemonergy.com/learn/glossary/can-bus/",
        "mentions": [
          "inverter"
        ]
      }
    },
    {
      "id": "term:state-of-power",
      "type": "Term",
      "label": "State of power",
      "properties": {
        "id": "state-of-power",
        "name": "State of power",
        "abbr": "SOP",
        "section": "topic-state",
        "definition": "The maximum charge or discharge power a battery can deliver for the next few seconds without breaking a voltage, current or temperature limit. The BMS recomputes it continuously from SOC, temperature and resistance and sends it to the motor controller.",
        "unit": "W",
        "related": [
          "power",
          "state-of-charge",
          "continuous-current",
          "derating",
          "bms",
          "state-of-function"
        ],
        "url": "https://lemonergy.com/learn/glossary/state-of-power/",
        "mentions": []
      }
    },
    {
      "id": "term:inverter",
      "type": "Term",
      "label": "Inverter",
      "properties": {
        "id": "inverter",
        "name": "Inverter",
        "aka": [
          "power conversion system",
          "PCS"
        ],
        "section": "topic-pack",
        "definition": "The power electronics that turn the battery’s DC into AC for a motor or the grid, and back again for charging. In stationary storage it is called the power conversion system and its rating in kW or MW sets the system’s power independently of the battery’s energy.",
        "related": [
          "pre-charge",
          "dc-dc-converter",
          "stationary-storage",
          "energy-management-system",
          "direct-current",
          "iec-62477-1"
        ],
        "url": "https://lemonergy.com/learn/glossary/inverter/",
        "mentions": []
      }
    },
    {
      "id": "term:ccu",
      "type": "Term",
      "label": "Charging control unit",
      "properties": {
        "id": "ccu",
        "name": "Charging control unit",
        "abbr": "CCU",
        "aka": [
          "charge control unit"
        ],
        "section": "topic-data",
        "definition": "The vehicle-side controller that manages charging: it detects the plug, talks to the charging station over the control pilot or ISO 15118 and DIN 70121, and passes the current and voltage limits the BMS allows. In some bus and truck architectures CCU also names a central or cluster control unit, so the system diagram decides.",
        "related": [
          "evcc",
          "iso-15118",
          "din-70121",
          "bms",
          "onboard-charger",
          "pantograph-charging"
        ],
        "url": "https://lemonergy.com/learn/glossary/ccu/",
        "mentions": [
          "control-pilot",
          "evse"
        ]
      }
    },
    {
      "id": "term:bms",
      "type": "Term",
      "label": "Battery management system",
      "properties": {
        "id": "bms",
        "name": "Battery management system",
        "abbr": "BMS",
        "section": "topic-pack",
        "definition": "The electronics and software that keep a battery inside its safe window: measuring every cell voltage and many temperatures, estimating SOC and SOH, balancing cells, computing current limits, controlling the contactors and reporting over the vehicle network.",
        "related": [
          "state-of-charge",
          "cell-balancing",
          "state-of-power",
          "cell-supervision-circuit",
          "contactor",
          "can-bus"
        ],
        "lesson": "fundamentals/battery-basics/#cell-module-pack",
        "url": "https://lemonergy.com/learn/glossary/bms/",
        "mentions": [
          "state-of-health",
          "cell-voltage"
        ]
      }
    },
    {
      "id": "term:electric-vehicle",
      "type": "Term",
      "label": "Electric vehicle",
      "properties": {
        "id": "electric-vehicle",
        "name": "Electric vehicle",
        "abbr": "EV",
        "aka": [
          "BEV",
          "battery electric vehicle"
        ],
        "section": "topic-applications",
        "definition": "A vehicle driven by an electric motor from a battery charged from the grid. A battery electric vehicle has no engine; it is the largest market for lithium-ion cells and the driver of most pack technology.",
        "related": [
          "hybrid-vehicle",
          "range",
          "pack",
          "regenerative-braking",
          "maritime-battery",
          "industrial-vehicle-battery"
        ],
        "url": "https://lemonergy.com/learn/glossary/electric-vehicle/",
        "mentions": []
      }
    }
  ]
}