Operation and Control of a Hybrid Coupled Interlinking Converter for Hybrid AC/LVDC Microgrids

In this project, a new structure of Hybrid Coupled Interlinking Converter (HCIC), which composed of a converter in series with a Static VAR Compensator (SVC) is proposed for hybrid AC and Low Voltage DC (LVDC) micro grids. Moreover, a new droop control method is correspondingly developed for the proposed HCIC. Its fundamental active and reactive power flow in the hybrid AC/DC micro grid is controlled by P-d and Q-P-V droop control for converter part of the HCIC, and P-Q-a droop control is proposed for SVC part of the HCIC. 

Furthermore, a fast harmonic control is given based on a decoupled control strategy to improve the filtering characteristics of SVC part of the HCIC, suppress the harmonic power, and/or inject active power. Finally, simulation and experimental results are provided to verify that the proposed HCIC for hybrid AC/LVDC micro grids has the ability of good power flow control and power quality compensation, which not only meets the power flow requirements with low rating system, but also greatly promotes the development of more robust hybrid AC/DC micro grids.

Keywords: Static VAR Compensator (SVC), Hybrid Coupled Interlinking Converter (HCIC), Low Voltage DC (LVDC) Micro Grids, Phase Locked Loop (PLL), Pulse Width Modulation (PWM).