Small-Signal Analysis of Parallel Connected Voltage Source Inverters Using a Frequency and Voltage Droop Control Including an Additional Phase Shift

[摘要] This paper presents a small-signal analysis of a stand-alone ac system composed by two or more voltage source inverters connected in parallel. Each inverter is controlled using a modified frequency and voltage droop method, which consists of the conventional frequency and voltage droop method including a further loop that feeds the power deviation from the nominal value back into the inverter phase. The proposed small-signal model of the system is presented, which is validated by simulation results. A root locus of the system is presented, which shows that the higher is the gain of further loop, the higher is the damping of the system. In order to show the viability of the proposed controller and proposed model, the results obtained from the model are compared with simulations and experimental results...

[学科分类] 自动化工程

[关键词] Frequency and voltage droop control ;Phase shift ;Parallel inverter connection without communications ;Small signal analysis