A Sum-of-Squares Optimization Method for Learning and Controlling Photovoltaic Systems

Xinwei Zhang, Victor Purba, Mingyi Hong, Sairaj Dhople

Research output: Chapter in Book/Report/Conference proceedingConference contribution


This paper outlines a combination of two data-driven approaches leveraging sum-of-squares (SoS) optimization to: i) learn the power-voltage (p-v) characteristic of photovoltaic (PV) arrays, and ii) rapidly regulate operation of the companion PV inverter to a desired power setpoint. Estimation of available headroom in PV systems is critical to the task of providing ancillary services, and the proposed method puts forth a computationally tractable solution with minimal data needs for the same. In addition to providing this key contribution to application, from an algorithmic vantage point, we present an interior-point method to solve a linear regression reformulation of the original polynomial fitting problem with SoS constraints. We validate the proposed algorithms through time-domain numerical simulations (incorporating the PV source and a 15-th order inverter model) for a variety of large-signal disturbances (step changes in real-power demand, rapid changes in irradiance) and demonstrate that the method provides an effective strategy to concomitantly discover the p-v curve and seamlessly regulate operation to a desired setpoint.

Original languageEnglish (US)
Title of host publication2020 American Control Conference, ACC 2020
PublisherInstitute of Electrical and Electronics Engineers Inc.
Number of pages6
ISBN (Electronic)9781538682661
StatePublished - Jul 2020
Event2020 American Control Conference, ACC 2020 - Denver, United States
Duration: Jul 1 2020Jul 3 2020

Publication series

NameProceedings of the American Control Conference
ISSN (Print)0743-1619


Conference2020 American Control Conference, ACC 2020
CountryUnited States

Bibliographical note

Funding Information:
This work was supported in part by the National Science Foundation through award 1453921.

Publisher Copyright:
© 2020 AACC.

Fingerprint Dive into the research topics of 'A Sum-of-Squares Optimization Method for Learning and Controlling Photovoltaic Systems'. Together they form a unique fingerprint.

Cite this