Based on the analysis of operation characteristics fault direct-drive permanent magnet wind turbine and existing protection strategies, in order to improve low-voltage capability turbine, a new coordinated control strategy for crossing is proposed this paper, which includes DC brake system unloading circuit, double second-order generalized integral phase-locked control, extracting positive nega...

This paper proposes a control technique for large-scale grid-connected photovoltaic (PV) plant that maintains the connection of an inverter to grid voltage under different types faults, while injecting reactive power accommodate required connection. strategy is suggested improve low-voltage ride-through (LVRT) capability PV generation plants. A 20 MW solar modeled and simulated using Matlab/Sim...

For the extraction of wind energy through a doubly-fed induction generator (DFIG), low voltage ride (LVRT) is an essential technical requirement specified by transmission system operator (TSO). Under grid fault condition, DFIG should remain in connection with for certain minimum period and offer reactive power support as required TSO. A cooperative control scheme consisting hardware solution su...

This paper presents an active crowbar, constructed with silicon controlled rectifiers (SCRs), for doubly fed induction generator (DFIG)-based wind turbines to fulfill low-voltage ride-through (LVRT) requirements demanded by grid codes. By this design, not only the active deactivation of the costly IGBT crowbar, replacing the passive crowbar for this ability, can be achieved with the more cost-e...

This paper proposes a competent and effective scheme to enhance the ride-through capability of DFIGbased wind turbines under unbalanced voltage dip conditions. The proposed method is realized through joint use of the rotor-side converter control and a three-phase stator damping resistor (SDR) placed in series with the stator windings. By means of an asymmetrical SDR idea, during the unbalanced ...

In this paper, the voltage sag ride-through capabilities of the line-connected electrically excited synchronous machine with damper windings (EESM) is investigated. We will design an algorithm for voltage sag ride through by controlling the flux. Two aspects are investigated, first the capability to keep the nominal speed and second the damping of speed oscillations. We will show through simula...