The lack of inertia contributions from renewable generators, which are essentially power electronic converters in replacement of synchronous generators, may greatly degrade the frequency regulation performance. As a solution, distributed virtual inert...
The lack of inertia contributions from renewable generators, which are essentially power electronic converters in replacement of synchronous generators, may greatly degrade the frequency regulation performance. As a solution, distributed virtual inertia provided by gridconnected power converters has been introduced as an effective approach to improve power system inertia. However, time-delays, which can be introduced by signal measurement, converter control, and communication, are ignored in the existing virtual inertia control implementations. To fill this research gap, this paper presents a detailed analysis of the effect of time-delays on virtual inertia control. It is revealed that instability will happen when the virtual inertia is greater than the existing power system inertia regardless of time-delays. In other cases, the system stability depends on time-delays, together with other design parameters. For verification, the experimental results are presented, which are consistent with the theoretical analysis.