In order to strengthen the ability in adopting unbalanced grid voltage, a sliding-mode control strategy of current for grid-connected converter with an LCL filter was proposed, and the sliding-mode governing equations of inner current loop and outer voltage loop were established, respectively. Dynamic quality and chattering effect of the designed sliding-mode controller were improved by using exponential rate control method. The referenced current was generated based on extended instantaneous power theory, and the objective of three-phase sinusoidal current was achieved while the second frequency fluctuation in both active and extended reactive power were eliminated. Finally, hardware-in-loop experimental platform based on RT-LAB was built. Results of comparative experiment demonstrated the correctness of proposed algorithm, as well as the excellent properties in dynamic response speed and parameter robustness.
HAN Gang,CAI Xu
. Sliding-Mode Control of Current for Wind Power Grid-Connected
Converter Under Unbalanced Grid Voltage[J]. Journal of Shanghai Jiaotong University, 2018
, 52(9)
: 1065
-1071
.
DOI: 10.16183/j.cnki.jsjtu.2018.09.009
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