A Novel DVR-ESS-Embedded Wind-Energy Conversion System

Enhanced LVRT capability of Wind Turbine based on DFIG using Dynamic Voltage Restorer controlled by ADRC-based Feedback control

“…According to the speed control methods, WTs can be classified into four basic configurations: fixed-speed with squirrel cage induction generator (SCIG), ±10% of speed variation with wound rotor induction generator (WRIG), ±30% of speed variation with doubly fed induction generator (DFIG), and Full-variable-speed with SCIG, permanent magnet synchronous generator (PMSG), or wound rotor synchronous generator (WRSG) [5,6]. However, further development of this wind turbine topology is imperatively limited by Low Voltage Ride Through (LVRT) capability, which is dictated by most grid codes to operate under voltage sags at Point of common coupling (PCC) and remain connected to the grid to support voltage during and postfault [7] [8]. With a focus on the LVRT capability of DFIG-WTs, many countries have updated their Grid Code Requirements (GCR).…”

“…The GSC is used to keep the DC-link voltage constant, as well as to control the reactive power output and the active power exchanged between the rotor and the grid [3,6]. DFIG-based WT has been shown to exhibit problematic FRT behavior compared to other types of WT [1,7]. It suffers from great sensitivity to grid voltage sags or swells.…”

“…(3) voltage of DC-link must remain constant to ensure the desired operation of the GSC and RSC [1,8,12]; (4) sufficient reactive power is needed to support grid recovery [1][2][3][4][5][6][7][8][9][10][11][12][13]. In order to overcome these restrictions and subsequently enhance the LVRT capability of DFIG-WTs, Extensive methods including external retrofit techniques and internal control techniques have been proposed [1].…”

“…Series dynamic braking resistors (SDBRs) and superconducting fault current limiters (SFCLs) are used as additional equipment to limit the inrush current undergone by the converters during transient conditions and to protect the rotor circuit against these transient overcurrents [17,18]. [7,10,15] prove that the DVR is capable of handling the transient fluctuations of a DFIG without need to other protective circuit during operation. The DVR is a competent voltage compensation device characterized by its fast response time as well as its better effect of restraining flicker [1,13,19].…”

LVRT capability enhancement of DFIG based wind turbine with coordination control of dynamic voltage restorer and inductive fault current limiter

“…When the DVR is to solve serious voltage decline with a longer duration, it is needed to consider sufficient energy support [20]. To deeply explore the potentials of the DVR, an enhanced voltage control basing the combination of feed-forward and feedback is proposed in [21], and an improved topological structure is discussed in [22]. Using the DVR can offer flexible transient- and steady-state response for the DFIG.…”