Transient energy dissipation control of energy storage devices in wind power generation systems

Abstract

The transient stability of power systems with high penetration of wind power generation can be significantly improved through the utilization of variable virtual inertia if the energy source of rotational inertia can be expanded by energy storage devices (ESDs). This paper first establishes the relationship of energy conversion between ESD and mechanical kinetic energy inside a synchronous generator (SG). Then, the impact of the controllable inertia on system frequency characteristics and power angle oscillation is analyzed using the small-signal model corresponding to this system. Based on the analysis of the change of transient energy at different stages in the transient process, the control of transient energy dissipation is proposed employing ESDs for reliable inertia support. Finally, a typical simulation system with high penetration of wind power generation is carried out to demonstrate the viability of the proposed control scheme. The test results show that the fluctuation of SG’s power angle and system frequency can be reduced by regulating the variable inertia in transient events, significantly improving the reliability of the inertia support provided by the ESDs.

Keywords

• Energy storage
• Virtual inertia
• Power angle oscillation
• Frequency characteristics
• Transient energy