Open AccessCarrier‐overlapping PWM‐based hybrid current control strategy applied to two‐stage grid‐connected PV inverter
Author(s) -
Liu Jiang,
Cheng Shanmei,
Shen Anwen
Publication year - 2018
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2016.0671
Subject(s) - pulse width modulation , photovoltaic system , waveform , inverter , control theory (sociology) , topology (electrical circuits) , controller (irrigation) , computer science , electronic engineering , voltage , engineering , electrical engineering , control (management) , artificial intelligence , biology , agronomy
For a wide dc input voltage range of photovoltaic (PV) array, a two‐stage grid‐connected inverter that allows input voltage regulation is required. This study proposes a topology with time‐sharing synchronous modulation in which energy transmission paths, wheeling branches and switching losses for high‐frequency switches are optimised to achieve efficiency improvement. The small‐signal model of proposed topology is analysed in detail. A hybrid current control strategy based on frequency‐amplitude domain analysis is presented. To solve further transitional problem on boost–buck mode switching, the controller uses a carrier‐overlapping pulse‐width modulation (PWM)‐based generator. Then, the effectiveness of the proposed topology and the control strategy under different experimental conditions are verified. Experimental results indicate hybrid current control strategy promotes current waveform quality and the burrs and oscillations in transition between buck mode and boost mode can be reduced.