Impedance interaction between islanded parallel voltage source inverters and the distribution network
Institution of Engineering and Technology (IET)
In an islanded microgrid consisting of parallel-connected inverters, the interaction between an inverter's output impedance (dominated by the inverter's filter and voltage controller) and the impedance of the distribution network (dominated by the other paralleled inverters' output impedances and the interconnecting power cables) might lead to instability. This paper studies this phenomenon using root locus analysis. A controller based on the second derivative of the output capacitor voltage is proposed to enhance the stability of the system. Matlab simulation results are presented to confirm the validity of the theoretical analysis and the robustness of the proposed controller.
This is the author accepted manuscript. The final version is available from IET via the DOI in this record.
7th IET International Conference on Power Electronics, Machines and Drives (PEMD 2014), Manchester, UK, 8-10 April 2014
7th IET International Conference on Power Electronics, Machines and Drives (PEMD 2014), pp. 1-6