Asymmetrical Fault Ride-Through and Power Oscillation Characterization for Grid-Tied Voltage Source Converters

As the number of converter-interfaced distributed energy resources connected to power system continues increase rapidly, recent grid codes require these grid-tied converters maintain connection during faults ensure supply security and reliability. In this work, we analyze oscillation in injected real reactive that a voltage source converter (VSC) introduces as it attempts contribute quality improve at point common coupling (PCC) an asymmetrical fault. We propose new double sequence current reference generation method can be utilized derive closed-form quantification peak value both fault ride-through (AFRT) analytically. The effect resulting bus ripple requirement twice frequency, corresponding oscillation, on input DC capacitor upstream is analyzed for facilitating component sizing. Furthermore, proposed formulation helps control negative-sequence injection assist with identification. theoretical analysis validated through simulation PLECS symmetrical scenarios. Experimental results three-phase, VSC operating under are provided evaluate performance validate presented