access icon free Enhanced proportional power sharing strategy based on adaptive virtual impedance in low-voltage networked microgrid

© The Institution of Engineering and Technology
Received 09/01/2018, Accepted 26/02/2018, Published 02/03/2018

The variation of the electrical distance and the complexity of the electric network lead to the variations of feeder impedances between distributed generation units and load points. It is determined that conventional droop control has drawbacks in achieving accurate power sharing due to the effects of mismatched impedance. Therefore, this study proposes an enhanced proportional power sharing strategy based on adaptive virtual impedance in a low-voltage networked microgrid. The improved R–L type droop control can effectively prevent the coupling between real and reactive powers. Furthermore, an adaptive virtual impedance loop is introduced to counteract the feeder voltage drop. The method utilises real and reactive power mismatching which were fed into integral controllers, and then generates the virtual inductive and resistive components, respectively. This proposed strategy is able to enhance power sharing accuracy without requiring the knowledge of feeder impedance, and it is more adaptive to the complex impedance. The simulation experiments carried out under the environment of MATLAB/Simulink, and results verify the effectiveness of the proposed strategy.

Inspec keywords: power generation control; distributed power generation; reactive power control

Other keywords: virtual inductive components; enhanced proportional power sharing strategy; improved R–L type droop control; distributed generation units; electric network complexity; Simulink; adaptive virtual impedance loop; virtual resistive components; reactive powers; low-voltage networked microgrid; mismatched impedance; MATLAB; load points; real powers; integral controllers; electrical distance variation; feeder impedances variations

Subjects: Control of electric power systems; Distributed power generation; Power and energy control; Power system control

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