Inertia Emulation in Power Converters with Communication Delays

Emulating inertia using power converter has been an effective way to provide additional inertia to power electronic dominated power systems. Currently, the control algorithms for emulating inertia have been proposed considering embedded implementation meaning that control algorithms are implemented in digital controller of power converter. However, it is not always feasible or cost-effective to upgrade control firmware of power converters. On the other hand, most of commercial power converter are equipped with at least one fieldbus interface, which can be employed for control purposes. This paper explores the possibility of emulating inertia by means of an external controller, which communicates with power converter via a communication link. Detailed analyses, especially regarding the influence of communication delays on the system stability and on performance indices such as RoCoF and frequency nadir, are given to provide insight into such an external implementation. The proposed implementation approach are also validated through simulations and hardware-in-the-loop (HIL) experiments.