{
  "$type": "site.standard.document",
  "description": "Control methods for an Energy Storage System (ESS) are provided which relates to the technical field of off-grid controlling and include: when the ESS operates in AC/DC parallel off-grid mode, obtaining given values of positive sequence voltage amplitude, positive sequence phase, D-axis and Q-axis…",
  "path": "/patents/1392278",
  "publishedAt": "2026-05-20T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "H02J4/25",
    "XIAMEN KEHUA DIGITAL ENERGY TECH CO LTD [CN]"
  ],
  "textContent": "Control methods for an Energy Storage System (ESS) are provided which relates to the technical field of off-grid controlling and include: when the ESS operates in AC/DC parallel off-grid mode, obtaining given values of positive sequence voltage amplitude, positive sequence phase, D-axis and Q-axis negative sequence voltage of a present PCS to be controlled based on a current sharing control loop; determining target control amounts of D-axis and Q-axis according to the given values, an outer voltage loop and an inner current loop; determining a zero-axis target control amount based on a zero-sequence current loop; determining a midpoint target control amount of a master PCS based on a DC bus midpoint control loop; generating a target waveform according to the target control amounts; and controlling the present PCS according to the first target waveform. The present disclosure solves the problem of current imbalance of each PCS and zero-sequence circulating current.",
  "title": "CONTROL METHOD FOR AN OFF-GRID ENERGY STORAGE SYSTEM, CONTROL DEVICE AND ENERGY STORAGE SYSTEM"
}