Direct Design Approach for Virtual Oscillator Control Synchronisation Condition & Parameter Selection using Describing Functions

Abstract

Virtual Oscillator Controls (VOCs) allow inverters to self-synchronise and form robust and stable microgrids. The existing design methodology requires an iterative tuning of key design parameters with time domain simulations required at each step. This paper presents an improved design methodology based on a per unit approach, Describing Functions (DFs) and control systems stability concepts. Direct calculation of key VOC parameters are derived, and this methodology is confirmed by simulation studies.