Discrete Time Nested-Loop Controller for the Output Stage of a Photovoltaic Microinverter

  • Oswaldo Lopez-SantosEmail author
  • Luis Cortes-Torres
  • Sebastián Tilaguy-Lezama
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 657)


This paper presents a comprehensive study of the digital implementation of the control requirements of the output stage of a two-stage solar microinverter. This approach uses a synchronized nested-loop controller which ensures the tracking of an internally generated high-quality current reference, the estimation and cancelation of the effect of the DC-link voltage ripple in the control loops and the regulation of the average value of the DC-link voltage. The proposed control architecture is validated by means of simulation results comparing operation of the inverter using continuous time, quasi-discrete time and discrete time implementations.


Microinverter Two-stage microinverter Cascade control Nested-loop controller 



This research is being developed with the partial support of the Gobernación del Tolima under Convenio de cooperación 1026 - 2013 - Research Culture. The results presented in this paper have been obtained with the assistance of students from the Research Hotbed on Power Electronic Conversion (SICEP), Research Group D+TEC, Universidad de Ibagué, Ibagué-Colombia.


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Copyright information

© Springer International Publishing AG 2016

Authors and Affiliations

  • Oswaldo Lopez-Santos
    • 1
    Email author
  • Luis Cortes-Torres
    • 1
  • Sebastián Tilaguy-Lezama
    • 1
  1. 1.Program of Electronics EngineeringUniversidad de IbaguéIbaguéColombia

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