Yoash Levron, Daniel Russel Clement, Beomseok Choi, Carlos Olalla, Dragan Maksimovic,
December 2014, Control of Sub-module Integrated Converters in the Isolated-Port Differential
Power-Processing Photovoltaic Architecture, IEEE Journal of Emerging and Selected
Topics in Power Electronics, Vol. 2, No. 4, pp. 821-832