A Novel Accurate Power Sharing Method Versus Droop Control In Autonomous Microgrids With Critical Loads

Abstract

In autonomous microgrids, the well-known frequency and voltage droop control are extensively used to share active and reactive powers among parallel inverters without using any communication infrastructure. However, power sharing is performed at the expense of altering the voltage and frequency of the system. To restore the voltage and frequency to their nominal amounts, a secondary control loop is often augmented to the system using communication links. To avoid using these complex hierarchical controls, this paper proposes a novel method for power sharing in parallel inverters providing constant frequency and nominal voltage operation for critical loads. The proposed method uses a simple structure based on communication links utilization. The simulation results show that the active and reactive powers are accurately shared with an acceptable transient response. Furthermore, the results are compared with the conventional droop control to show the superiority of the proposed method over the conventional one.

Keywords

• Autonomous microgrid
• active and reactive power sharing
• constant frequency operation
• critical loads