Abstract In this paper, a grid-connected current control based on D-Σ digital control is studied to improve the grid-connected performance of three-level T-type inverter, accelerate the dynamic response speed and improve the steady state control accuracy of the grid-connected inverter system. The transient mathematical model is established according to the single-phase equivalent circuit of the three-level T-type inverter. The principle of D-Σ digital control is deeply analyzed, and an estimation method of common-mode voltage between neutral point of the power grid and neutral-point of the DC bus is proposed. The dynamic and static performance of D-Σ digital control is compared with that of traditional deadbeat control. The validity of D-Σ digital control and the correctness of the common-mode voltage estimation are proved by simulations and experiments, which demonstrates the excellent dynamic and static performance of the algorithm.
Ren Biying,Sun Xiangdong,Yu Majing等. D-Σ Control Algorithm of Grid-Connected Current for a Three-Level T-Type Inverter[J]. Transactions of China Electrotechnical Society, 2019, 34(8): 1708-1717.
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2019, Vol. 34 
