Small Signal Stability Study for Island Distributed Generation System Controlled by IDA-PBC-IA and Power Decoupled Droop Control

The supply of electricity to remote areas such as islands or rural areas presents many challenges. To reduce costs, the use of renewable energy resources is recommended. In these circumstances, it is always important to improve the power quality in terms of waveform and power sharing between different distributed generators. In this paper, we focus on the power sharing between different distributed generators, and for this purpose, an improved decoupled control, proposed in our previous work, is studied to prove its effectiveness in providing wide range of stability. The internal control has been assimilated to a second-order filter and then, the improved decoupled control is studied to prove its effectiveness to ensure a wide range of stability. For this purpose, a microgrid composed of two distributed generators is studied. Its small-signal model including the distributed generators, the loads and the droop control laws that ensure the interconnection between the generators is revealed. A stability study in the sense of the indirect Lyapunov theory based on the evaluation of the eigenvalues of the system is performed to show the “local stability” in presence of different types of loads, the impact of the system and the control parameters on the eigenvalue is studied using the modal analysis technique. The validation of these results is proven by simulation