Virtual oscillator control (VOC) is a decentralized time-domain control technique for ac microgrids where inverters are regulated to emulate the dynamics of weakly nonlinear oscillators. VOC enables the design of modular and scalable systems where inverters can synchronize and share power without communication and in near real-time. In this paper, we show how off-the-shelf commercial inverters with current control can be reprogrammed to behave as voltage sources with virtual oscillator dynamics for deployment in islanded settings. We focus on commercial grid-tied inverters that have an inner current-control loop and show how the outer-loop controls can be straightforwardly modified to enable voltage-control-mode operation. To illustrate the practicality and ease of our approach, the proposed strategy was implemented on a 3.2 kVA experimental test bed composed of 10 SunPower-brand micro-inverters with special firmware for VOC implementation. Results from the experiments not only demonstrate feasibility of the proposed dual-loop VOC architecture on a hardware setup but also show improved voltage regulation due to the additional voltage control loop.
|Original language||English (US)|
|Title of host publication||34th Annual IEEE Applied Power Electronics Conference and Exposition, APEC 2019|
|Publisher||Institute of Electrical and Electronics Engineers Inc.|
|Number of pages||6|
|State||Published - May 24 2019|
|Event||34th Annual IEEE Applied Power Electronics Conference and Exposition, APEC 2019 - Anaheim, United States|
Duration: Mar 17 2019 → Mar 21 2019
|Name||Conference Proceedings - IEEE Applied Power Electronics Conference and Exposition - APEC|
|Conference||34th Annual IEEE Applied Power Electronics Conference and Exposition, APEC 2019|
|Period||3/17/19 → 3/21/19|
Bibliographical noteFunding Information:
This work was supported in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36 − 08GO28308. Funding was also provided by the DOE Office of Energy Efficiency and Renewable Energy Solar Energy Technologies Office under grant No. DE-EE0000 − 1583. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. Funding was also provided by the National Science Foundation through grants 1453921 and 1509277.
© 2019 IEEE.