This paper proposes a cascade repetitive control strategy based on odd internal mode,and combines it with proportional-integral(PI)control to establish a compound repetitive control system for improving the quality of...This paper proposes a cascade repetitive control strategy based on odd internal mode,and combines it with proportional-integral(PI)control to establish a compound repetitive control system for improving the quality of grid connected current of LCL grid connected inverter.More specifically,the proposed method could effectively improve the control effect of grid-connected current of LCL inverter,restrain current harmonics and reduce the distortion rate of grid-connected current.Simulation experiment is conducted to verify the proposed repetitive control strategy,and the verification results show that,compared with traditional PI control,the proposed improved compound repetitive control strategy has a higher response speed,and the steady-state and dynamic performance have also been significantly improved.展开更多
The harmonic disturbance in the background grid is a problem that must be considered in the design of a gridconnected inverter.However,the full feed-forward method cannot completely suppress the harmonic disturbance i...The harmonic disturbance in the background grid is a problem that must be considered in the design of a gridconnected inverter.However,the full feed-forward method cannot completely suppress the harmonic disturbance in theory and is sensitive to noise.To tackle these problems,a fractional full feed-forward method of grid voltage is proposed in this paper.First,the mathematical model of the full feed-forward method is deduced,and the differences with the theoretical solution,which can suppress all harmonics,are analyzed.Then,the parameter equation,the harmonic suppression performance,stability analysis and the implementation process of this method are given.Compared with the full feed-forward method,the proposed method not only further improves the harmonic suppression performance,but also reduces the order of the mathematical model of the differential term in the feed-forward loop.In addition,the proposed method can be used to flexibly design feed-forward coefficients by selecting the order of suppressed harmonics.Finally,the proposed method is validated by a hardware-in-the-loop experiment on a MT real-time control platform NI PXIE-1071.展开更多
基金supported by the National Natural Science Foundation of China(No.61903291)。
文摘This paper proposes a cascade repetitive control strategy based on odd internal mode,and combines it with proportional-integral(PI)control to establish a compound repetitive control system for improving the quality of grid connected current of LCL grid connected inverter.More specifically,the proposed method could effectively improve the control effect of grid-connected current of LCL inverter,restrain current harmonics and reduce the distortion rate of grid-connected current.Simulation experiment is conducted to verify the proposed repetitive control strategy,and the verification results show that,compared with traditional PI control,the proposed improved compound repetitive control strategy has a higher response speed,and the steady-state and dynamic performance have also been significantly improved.
基金supported in part by the National Natural Science Foundation of China(61703375).
文摘The harmonic disturbance in the background grid is a problem that must be considered in the design of a gridconnected inverter.However,the full feed-forward method cannot completely suppress the harmonic disturbance in theory and is sensitive to noise.To tackle these problems,a fractional full feed-forward method of grid voltage is proposed in this paper.First,the mathematical model of the full feed-forward method is deduced,and the differences with the theoretical solution,which can suppress all harmonics,are analyzed.Then,the parameter equation,the harmonic suppression performance,stability analysis and the implementation process of this method are given.Compared with the full feed-forward method,the proposed method not only further improves the harmonic suppression performance,but also reduces the order of the mathematical model of the differential term in the feed-forward loop.In addition,the proposed method can be used to flexibly design feed-forward coefficients by selecting the order of suppressed harmonics.Finally,the proposed method is validated by a hardware-in-the-loop experiment on a MT real-time control platform NI PXIE-1071.