Voltage control strategy for DC microgrid based on adaptive PI controller

doi:10.3969/j.issn.1674-1951.2021.09.002

Abstract

Abstract:

Since traditional control strategies cannot balance voltage disturbance level and total harmonic distortion（THD）of power grid,a DC bus voltage control strategy based on adaptive PI controller is proposed.The control objective of the strategy is to lower the harmonic distortion rate of the grid and the voltage disturbance simultaneously,and the strategy analyzes and executes by using a dynamic simplified model of current control loops.The proposed adaptive PI controller's proportional and integral gains are self-regulating,which can decrease the voltage fluctuation level and the THD of the grid while ensuring fast response.The results show that,compared with traditional control methods,the proposed control method can boost the anti-disturbance capacity of bus voltage and lower the THD in steady state.

Key words: DC microgrid, single-phase AC/DC converter, adaptive PI controller, voltage control, THD, anti-disturbance capacity, quick response

CLC Number:

TK732

WU Xiaotao, TAN Chao, WANG Guobo. Voltage control strategy for DC microgrid based on adaptive PI controller[J]. Huadian Technology, 2021, 43(9): 14-22.

Figures/Tables 11

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参数	数值
交流侧电压/V	380
滤波电感/H	0.06
频率f/Hz	50
直流母线电压/V	400
直流侧电容/μF	220
直流侧负载/Ω	100
缓冲电阻R_s/kΩ	100
电流内环控制增益K	0.475
外部频带值的比率/%	10