Simple Tuning Method of Virtual Synchronous Generators Reactive Control

The integration of renewable energy sources requires new control strategies to make static converters able to provide ancillary grid services, such as virtual inertia and grid support during faults. To address this issue, the idea of making inverters behave as synchronous machines is well known in the literature as the concept of Virtual Synchronous Generator. Thanks to this solution, inverters can provide both inertia and reactive grid support as traditional synchronous machines. However, the tuning of the excitation control of Virtual Synchronous Generator for proper reactive power management has not been properly analyzed in the literature. Therefore, the goal of this paper is to provide a simple tuning criterion for the VSM excitation control with improved dynamic behavior using a feed-forward term. This way, the VSM is able to provide the desired reactive support during faults and quickly track the desired reactive power setpoints. Both a theoretical analysis and experimental tests are provided for a 15 kVA system.