Dual-Current Loops Control Strategy of PWM Rectifier under Unbalanced Grid Voltage Conditions

Abstract:

The unbalanced grid voltage causes the current harmonics, the fluctuation of the active power in AC side and the fluctuation of the DC voltage. The dual-current loops control strategy can slove those problems. The positive and negative sequence components of grid voltages and currents were calculated based on the symmetrical component method and were used to calculate the instantaneous power in double dq rotate coordinate, which ratate at positive and negative synchronous angular velocity respectively. The dual-current loops control strategy was finally verified in simulation by comparing with the conventional synchronous PI current control. The simulation results show the dual-current loops control strategy is effective on eliminating the fluctuation of the active power in AC side and the fluctuation of the DC voltage.

• Periodical: Applied Mechanics and Materials (Volumes 556-562)
• Pages: 2114-2118
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.556-562.2114
• Online since: May 2014
• Authors: Yi Feng Ni*, Yong Qiang Zhu
• Keywords: Dual Current Loops, Grid Voltage Unbalance, Negative Sequence Component, Positive, VSR

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