LCL型并网逆变器新型电容电压有源阻尼策略

杨明; 宋明洋; 张国澎; 解宝

doi:10.19912/j.0254-0096.tynxb.2021-1052

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太阳能学报 ›› 2023, Vol. 44 ›› Issue (2) : 399-408. DOI: 10.19912/j.0254-0096.tynxb.2021-1052

LCL型并网逆变器新型电容电压有源阻尼策略

杨明¹, 宋明洋¹, 张国澎¹, 解宝²

作者信息 +

NEW TYPE CAPACITTIVE VOLTAGE ACTIVE DAMPING STRATEGY FOR LCL GRID-CONNECTED INVERTER

Yang Ming¹, Song Mingyang¹, Zhang Guopeng¹, Xie Bao²

Author information +

文章历史 +

摘要

在弱电网条件下,数字控制延时会导致虚拟阻抗呈现负阻性,无法起到阻尼效果,因此并网逆变器在电网阻抗变化情况下不能稳定运行,鲁棒性受到严重威胁。针对上述问题,提出一种双线性正反馈有源阻尼策略,以扩大系统的有效阻尼区。为了节省传感器成本,将其优化为电容电压正反馈有源阻尼策略,在电容电压两端添加合适的正反馈阻尼环节,使得系统的有效阻尼区扩大为（0,0.477f₃）。分析结果表明该策略使得并网逆变器在弱电网条件下始终具有良好的鲁棒性,即使谐振频率等于1/6采样频率时,系统也具有较好的稳定性。最后,以三相LCL型并网逆变器为例进行实验验证,实验结果验证了该策略的正确性。

Abstract

Under weak grid conditions, the digital control delay will cause the virtual impedance to show negative resistance and cannot achieve the damping effect. Therefore, the grid-connected inverter cannot operate stably under the change of grid impedance, and its robustness is seriously threatened. In response to the above problems, this paper proposes a bilinear positive feedback active damping strategy to expand the effective damping zone of the system. To save the cost the sensors, it is optimized as a capacitive voltage positive feedback active damping strategy, adding appropriate positive feedback damping links at both ends of the capacitor voltage, so that the effective damping area of the system is expanded to （0, 0.477f_s）. The analysis results show that this strategy makes the grid-connected inverter always have good robustness under weak grid conditions, and the system has good stability even when the resonance frequency is equal to 1/6 of the sampling frequency. Finally, a three-phase LCL grid-connected inverter is taken as an example to carry out experimental verification, and the experimental results verify the correctness of the strategy.

导出引用

杨明, 宋明洋, 张国澎, 解宝. LCL型并网逆变器新型电容电压有源阻尼策略[J]. 太阳能学报. 2023, 44(2): 399-408 https://doi.org/10.19912/j.0254-0096.tynxb.2021-1052

Yang Ming, Song Mingyang, Zhang Guopeng, Xie Bao. NEW TYPE CAPACITTIVE VOLTAGE ACTIVE DAMPING STRATEGY FOR LCL GRID-CONNECTED INVERTER[J]. Acta Energiae Solaris Sinica. 2023, 44(2): 399-408 https://doi.org/10.19912/j.0254-0096.tynxb.2021-1052

中图分类号： TM464

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