Enhancing the Performance of DFIG Wind Turbines Considering Excitation Parameters of the Insulated Gate Bipolar Transistors and a New PLL Scheme

Abstract

The major aim for achieving the successful synchronization of a wind turbine system to the grid is to mitigate electrical and mechanical stresses on the wind generator. During transient state, the gearbox, shaft, and rotor of the wind generator could be damaged due to mechanical stress. The rotor and stator windings of the wind generator, including its insulation, could be affected. This paper undertakes an extensive analysis of the effects of the excitation parameters of the power converter Insulated Gate Bipolar Transistors (IGBTs), on the transient state performance of the Doubly Fed Induction Generator (DFIG), considering different scenarios. The optimal excitation parameters of IGBTs were used for further analysis of the wind generator, considering a new Phase-Locked-Loop (PLL) scheme. The PLL computes the phase displacement of the grid required to achieve orientation and synchronization control. Consequently, it helps in preventing power system distortion due to stator-grid interphase. This paper proposes a new approach that integrates PLL control strategy and a Series Dynamic Braking Resistor (SDBR) to augment the fault ride through capability of a variable speed wind turbine that is DFIG-based. The SDBR helps the post fault recovery of the wind generator. Simulations were run in Power System Computer Aided Design and Electromagnetic Transient state Including DC (PSCAD/EMTDC) to examine severe fault conditions, and to test the robustness of the controllers employed. The results show that the proposed hybrid control strategy aids the fast recovery of the DFIG wind generator variables during fault conditions.

Enhancing the Transient State Performance of Permanent Magnet Synchronous Generator Based Variable Speed Wind Turbines Using Power Converters Excitation Parameters

“…The same condition of operation was considered as above for the PMSG wind turbine. The simulation results for some of the key variables of the DFIG are shown in Figures 15-19, based on (Okedu and Barghash, 2021).…”

“…The excitation parameters of the IGBTs that were investigated include the turn on and turn off resistances. It has already been reported in Okedu and Barghash (2021) that the forward break over and reverse withstand voltages have no much effects on the transient performance of the variable speed wind generators. An extensive analysis of the effects of the excitation parameters of the IGBTs was carried out by considering three scenarios of the IGBT's turn on resistances with and without considering DC-chopper braking resistor for over voltage protection of the PMSG wind turbine.…”

Wind energy conversion technologies and engineering approaches to enhancing wind power generation: A review

“…Among these technologies, the two-level (2L) – current source converter (CSC) [ 15 , 16 ], and voltage source converter (VSC) [ 11 , 17 ] topologies in back-to-back (BTB) configurations were conventionally being employed in small- and medium-scale wind farms for the last several decades; and they were usually compatible with DFIG-based WECS technology. Here, one of the main drawbacks of DFIG-based WECS is that it does not maintain operational compatibility with power converters of increasing power and voltage capacities [ 18 ]. Nevertheless, besides its considerable cost advantages, this technology is largely suitable for the vast application in small- and medium-scale onshore wind generation particularly with BTB 2L-VSC [ 19 , 20 ].…”

Research on Short-Circuit Current Calculation Method of Doubly-Fed Wind Turbines Considering Rotor Dynamic Process

“…DFIG are widely used in wind farms as their main turbines, because of the advantages of the wide range of operating wind speeds and the decoupled control of active and reactive power (Tamaarat and Benakcha, 2014;Firouzi and Gharehpetian, 2017;Sun and Wang, 2018;Okedu, and Barghash, 2020). However, with the increase of DFIG, the influence of the transient process of DFIG on the short-circuit current calculation cannot be ignored.…”