引用本文: | 韩刚,蔡旭.不平衡及畸变电网下并网变流器的比例多谐振电流控制[J].电力自动化设备,2017,37(11): |
| HAN Gang,CAI Xu.Proportional multi-resonance current control of grid-connected converter under unbalanced and distorted grid condition[J].Electric Power Automation Equipment,2017,37(11): |
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摘要: |
针对不平衡及畸变电网电压影响并网变流器控制性能的问题,采用比例多谐振调节器对变流器的电流环进行控制。在建立两相静止坐标系下变流器数学模型的基础上,给出一种采用直流电压外环、电流内环的双环控制结构,电流内环选择比例多谐振调节器实现了对基波电流的跟踪和对畸变电网电压扰动的抑制。针对含有LCL型滤波器的变流器中滤波器以及比例多谐振调节器阶数高、参数设计困难的问题,基于离散域根轨迹分析,提出了比例多谐振调节器参数设计的方法。通过分析谐振调节器参数对系统闭环极点的影响,设计了电流环的控制参数,该参数可使系统在滤波器及电网频率变化时仍然具有较好的鲁棒性。在RT-LAB硬件在环实验平台上,验证了电流控制方法的可行性,以及所提比例多谐振调节器参数设计方法的正确性。 |
关键词: 不平衡及畸变电网 并网变流器 比例多谐振调节器 参数设计 根轨迹 离散域 电流控制 |
DOI:10.16081/j.issn.1006-6047.2017.11.017 |
分类号:TM46 |
基金项目:台达环境与教育基金会《电力电子科教发展计划》资助项目(DREM2016005) |
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Proportional multi-resonance current control of grid-connected converter under unbalanced and distorted grid condition |
HAN Gang, CAI Xu
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Wind Power Research Center, Shanghai Jiao Tong University, Shanghai 200240, China
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Abstract: |
Aiming at impacts of the unbalanced and distorted voltage on grid-connected converter perfor-mance, the proportional multi-resonance regulator is adopted to optimize the current loop. On the basis of the converter model in two-phase static axis, a dual-loop control structure with both the DC outer-voltage loop and the inner-current loop is presented. To track the reference current and suppress the voltage disturbance, the proportional multi-resonance regulator is adopted in the current loop. As for the converters with LCL filter, the order of filter and proportional multi-resonance regulator is high and the parameter design is complicated, aiming at which, a regulator parameter design method based on the root locus analysis in the discrete domain is proposed. Effects of the resonance regulator parameters on the system closed-loop poles are analyzed, based on which the control parameters of the current loop are designed to guarantee the robustness against the fluctuation in the LCL filter parameters and grid frequency. On the RT-LAB-based hardware-in-loop experimental platform, the feasibility of the current control method and the effectiveness of the proposed regulator parameter design method are verified. |
Key words: unbalanced and distorted grid grid-connected converter proportional multi-resonance regu-lator parameter design root locus discrete domain electric current control |