In this article, an improved dc-link voltage regulation strategy is proposed for grid-connected converters applied in dc microgrids. For the inner loop of the grid-connected converter, a voltage modulated direct power control is employed to obtain two second-order linear time-invariant systems, which guarantees that the closed-loop system is globally exponentially stable. For the outer loop, a sliding mode control strategy with a load current sensor is employed to maintain a constant dc-link voltage even in the presence of constant power loads at the dc-side, which adversely affect the system stability. Furthermore, an observer for the dc-link current is designed to remove the dc current sensor at the same time improving the reliability and decreasing the cost. From both simulation and experimental results obtained from a 15-kVA prototype setup, the proposed method is demonstrated to improve the transient performance of the system and has robustness properties to handle parameter mismatches compared with the input-output linearization method.
Improved DC-Link Voltage Regulation Strategy for Grid-Connected Converters
2021-06-01
Gui , Y , Blaabjerg , F , Wang , X , Bendtsen , J D , Yang , D & Stoustrup , J 2021 , ' Improved DC-Link Voltage Regulation Strategy for Grid-Connected Converters ' , I E E E Transactions on Industrial Electronics , vol. 68 , no. 6 , 9080581 , pp. 4977-4987 . https://doi.org/10.1109/TIE.2020.2989720
Aufsatz (Zeitschrift)
Elektronische Ressource
Englisch
DDC: | 629 |
BASE | 2019
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