Study on the energy stability region of DFIG-integrated power system with virtual inertia

Currently available research on the oscillatory stability of doubly-fed induction generator (DFIG) integrated power system can hardly depict the dynamic characteristics of DFIGs with inertia support capability. The dynamic energy stability region of DFIG-integrated power system with virtual inertia is constructed in this paper. First, a dynamic model of the wind farm is built and the dynamic energy function of DFIG during oscillation is derived. The dissipation energy model of DFIG-integrated power system is established, and the functional relationship between the dissipation energy and the critical energy of the system is explored. Then, the dynamic energy stability region of DFIG-integrated power system is constructed according to the energy curve formed by the critical energy points. Based on this, the effects of the virtual inertia and PLL control parameters on the energy stability region are revealed. Simulation tests performed in RTDS verify that, the proposed method is applicable to the system with multiple oscillation modes. It can effectively evaluate the tolerance of the system to disturbances, and can quantitatively analyze the effects of the control parameters on the energy stability regions of intra-area and inter-area oscillation modes.

Automated summary

This paper investigates the oscillatory stability of doubly-fed induction generator (DFIG) integrated power system with virtual inertia. By establishing dynamic models and energy stability region, the effects of virtual inertia and PLL control parameters on the energy stability region are revealed.