带恒功率负荷并联Boost DC/DC电压源组网系统稳定性分析

肖朝霞; 李盼; 朱洪驰; 张世荣; 曹家宁

doi:10.12204/j.issn.1000-7229.2023.03.013

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电力建设 ›› 2023, Vol. 44 ›› Issue (3) : 122-137. DOI: 10.12204/j.issn.1000-7229.2023.03.013

新能源发电

带恒功率负荷并联Boost DC/DC电压源组网系统稳定性分析

肖朝霞 ¹ ,
李盼 ¹ ,
朱洪驰 ¹ ,
张世荣 ² ,
曹家宁 ²

作者信息 +

Stability Analysis of Paralleled Boost DC/DC Voltage-Source Interfaced System with Constant Power Load

Author information +

文章历史 +

摘要

针对直流组网中并联Boost DC/DC变换器带恒功率负荷的“源-荷”级联系统稳定性问题,利用特征值法和阻抗比法重点分析了并联Boost DC/DC变换器系统的稳定性和带恒功率负荷的能力,并通过时域仿真法验证理论分析的正确性,系统性比较了V-I和I-V下垂控制在并联Boost DC/DC变换器系统应用中的优缺点。多台并联Boost DC/DC变换器带阻感负荷时,控制器参数的稳定域基本不随并联台数的增加而改变,V-I下垂系统随虚拟阻抗减小(I-V下垂系统随虚拟阻抗增加)系统稳定性变差;带恒功率负荷时,系统带载能力大小变化与稳定性方向一致。相同虚拟阻抗下,多台并联V-I下垂系统带载能力大于I-V下垂系统。为V-I和I-V两类下垂控制在并联Boost DC/DC变换器实际工程中的应用提供了一般设计规律。

Abstract

Aiming at the stability problem of source-load cascade system with constant power load in paralleled Boost DC/DC converter in DC network, the stability of the paralleled Boost DC/DC converters and the load capacity with constant power load are analyzed by eigenvalue method and impedance ratio method. The correctness of the theoretical analysis is verified by the time-domain simulation method, and the advantages and disadvantages of V-I and I-V droop control for the load power sharing are systematically compared in this paper. For multiple paralleled Boost DC/DC converters with resistance load, the stability region of controller parameters does not change with the increase of the number of paralleled units. The decrease of virtual impedance in V-I droop system, or the increase of virtual impedance in I-V droop system will lead to the deterioration of system stability. For multiple paralleled Boost DC/DC converters with constant power load, the change of the load capacity of the system is consistent with the stability. With the same virtual impedance, the load capacity of multiple paralleled V-I droop system is greater than that of I-V droop system. This paper provides general design rules for two types of droop control in practical engineering applications of parallel Boost DC/DC converters.

导出引用

肖朝霞, 李盼, 朱洪驰, 等. 带恒功率负荷并联Boost DC/DC电压源组网系统稳定性分析[J]. 电力建设. 2023, 44(3): 122-137 https://doi.org/10.12204/j.issn.1000-7229.2023.03.013

Zhaoxia XIAO, Pan LI, Hongchi ZHU, et al. Stability Analysis of Paralleled Boost DC/DC Voltage-Source Interfaced System with Constant Power Load[J]. Electric Power Construction. 2023, 44(3): 122-137 https://doi.org/10.12204/j.issn.1000-7229.2023.03.013

中图分类号： TM712

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