Virtual Synchronous Machine Control for Asynchronous Grid Connections

The reduced amount of large synchronous generators results in the need for fast, flexible, and intelligent power distribution devices to enhance the inertia in the modern power system. This paper proposes a new approach to control an asynchronous low-voltage grid connection, employing a virtual synchronous machine with frequency-based power control. The grid-forming converter, receiving the primary side frequency measurement, varies the fed grid frequency on the secondary side artificially, to interact with frequency-dependent resources. This enables the adjustment of the consumed or generated power in the fed grid without the need for additional communication infrastructure, and thus supports the frequency control of the mains. The performance of the proposed frequency control has been validated through simulation and using a newly developed double Power Hardware-in-the-Loop experimental test setup.