Double synchronous unified virtual oscillator control for grid-forming and grid-following power electronic converters

A double synchronous unified virtual oscillator controller of a power electronic converter in a power grid, comprising:

• a double synchronous space vector oscillator configured to generate a voltage vector output using feedback of an output current of the power electronic converter, the double synchronous space vector oscillator comprising a double sequence current reference generation component, a double sequence vector limiter component, a positive sequence space vector oscillator component, and a negative sequence space vector oscillator component;
• a sequence extraction component that is configured to extract positive and negative sequence symmetrical components of the output current of the power electronic converter;
• a fault detection component that is configured to detect and latch a fault condition based on the feedback of the output current of the power electronic converter or a grid voltage at a point-of-coupling of the power electronic converter with the power grid;
• a virtual impedance component that is configured to achieve harmonic current suppression in the output current of the power electronic converter;
• an observer based active damping component that is configured to achieve resonance damping in a high frequency range originating from a higher-order filter of the power electronic converter, wherein the higher-order filter is at least a second order filter;
• a terminal voltage compensation component that is configured to compensate a voltage deviation due to the higher-order filter or other non-ideal effects of the power electronic converter;
• and
• a pre-synchronization component that is configured to synchronize the double synchronous space vector oscillator with a terminal voltage of the power electronic converter at the point-of-coupling before being connected to the power grid,
• wherein the double synchronous unified virtual oscillator controller is configured to control the power electronic converter for both grid forming and grid following operations.