Permanent magnet synchronous generator converter protection analysis during DC wind farm open-circuit fault condition

This paper discusses the protection schemes for the converter of permanent magnet synchronous generator (PMSG) to enhance the fault ride-through (FRT) capability. The power conversion topology of the studied system includes a rectifier, DC/DC boost converter and a voltage source inverter (VSI) connected to the grid. A protection scheme with rectifier-boost damping resistor and inverter DC-link voltage damping resistor is proposed as the main protection devices. After the analysis of fault condition, protection resistance value is calculated for practical application. The protection switching and FRT performance are simulated with PSCAD/EMTDC, including power and torque fluctuation, rectifier voltage, and rotor speed with and without protection scheme. The proposed protection scheme can effectively protect the system, hence improving the PMSG fault ride-through performances.