On Virtual Complex Impedance Droop Control of VSC-Based Islanded Microgrids

• This paper investigates the droop control techniques used to ascertain the proper sharing of active and reactive power of multiple VSCs in an islanded microgrid. The dynamic model of the system control loops is performed in a dq rotating reference frame. The droop control loop is analyzed, taking into account the inductive nature of the output impedance of the microgrid due to the inductor of the filter and coupling inductor. To minimize the circulating current that flows between parallel VSC, a virtual complex impedance loop is included in the proposed controller. In order to avoid the stability problem occurring at the resonant frequency of the LCL filter, a parallel resistor is added to the LCL filter capacitor. For both equal and proportional power-sharing strategies, the proposed controller can achieve accurate power-sharing with an excellent dynamic performance of the system. The simulation results are presented to reveal the accurate performance of the proposed controller.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik -- Annan elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering -- Other Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Keyword

Droop control

Microgrids

Parallel passive damping

virtual complex impedance

VSC

Publication and Content Type

ref (subject category)

kon (subject category)