Small-Signal Stability of a Power System with a VSWG Affected by the PLL
Grid connection of a VSWG to a power system is realized by the converter control, which normally adopts the current vector control algorithm. This has been introduced in Chap. 2. Implementation of current vector control needs to track the relative positions between the d − q coordinate of the converter and the common x − y coordinate of the power system in order to determine the d − q coordinate of the converter. As being illustrated by Fig. 2.8, the direction of the terminal voltage (PCC voltage) of a PMSG in x − y coordinate of the power system is normally taken as that of d axis of d − qcoordinate of the GSC of the PMSG. Figure 2.10 shows that the direction of the terminal voltage (PCC voltage) of a DFIG in x − y coordinate of the power system is often taken as that of d axis of d − q coordinate of the RSC of the DFIG. Hence, by tracking the phase of the terminal voltage of the VSWG, d − q coordinate of the converter can be determined for implementing the current vector control. This task of phase tracking is normally fulfilled by a phase locked loop (PLL).
- 1.Wang YJ, Hu JB, Zhang DL, Ye C, Li Q (2015) DFIG WT Electromechanical transient behavior influenced by PLL: modelling and analysis. In: International conference of renewable power generation, Beijing, pp 1–5Google Scholar
- 2.Wang ZW, Shen C, Liu F (2014) Impact of DFIG with phase lock loop dynamics on power systems small signal stability. In: IEEE PES general meeting, National Harbor, MD, pp 1–5Google Scholar
- 6.Shi L, Crow ML (2008) A novel PLL system based on adaptive resonant filter. In: 40th North American Power Symposium, Calgary, AB, pp 1–8Google Scholar
- 7.Timbus A, Liserre M, Teodorescu R, Blaabjerg F (2005) Synchronization methods for three phase distributed power generation systems—An overview and evaluation. In: IEEE 36th power electronics specialists conference, Recife, pp 2474–2481Google Scholar
- 9.Padiyar KR (1996) Power system dynamics stability and control. Wiley, New YorkGoogle Scholar
- 13.MATLAB Simulink wind farm-DFIG detailed model. https://uk.mathworks.com/help/physmod/sps/examples/wind-farm-dfig-detailed-model.html