新能源基地柔性直流送出系统小扰动强度评估方法

• 作者： 马富艺龙 ¹ 辛焕海 ¹ 刘晨曦 ¹ 李诗旸 ² 袁辉 ¹ 代江 ³
• 作者单位：
  1.  浙江大学电气工程学院

  2.  南方电网科学研究院

  3.  贵州电网有限责任公司电力调度控制中心
• 提交时间：2023-06-06

摘要: 系统强度概念常用于描述系统电压响应性能和量化安全稳定水平，其中基于短路比的强度量化指标在描述新能源送出极限时具有简单直观的特点。然而，现有基于短路比的分析基础是以同步机提供短路容量或电压支撑为前提，难以适用于无同步机支撑的新能源基地柔性直流送出系统。为此，本文从小扰动角度探讨新能源基地柔性直流送出系统的强度评估和分析问题，首先推导了该系统中多端口电流对母线电压的灵敏度传递函数矩阵，阐述了受扰后母线电压响应与系统静态电压稳定/小扰动同步稳定的定性关系。其次，基于送端柔直电压源等值思路，并结合新能源设备临界短路比提出了系统强度源-网分离的评估方法，将广义短路比推广应用到全电力电子系统。所提出的方法能快速分析在系统运行点处的静态电压稳定/小扰动同步稳定裕度，确定系统强度的薄弱环节以及系统强度提升的优化路径。最后，多风电场经柔性直流送出系统算例验证了评估方法的有效性。

Abstract: System strength is generally used to describe the voltage response performance under a disturbance and quantify the stability margin. The system strength indicated by short-circuit ratio (SCR) has provided a simple and intuitive reference for grid operators. However, the existing SCR-based methods rely on the premise that synchronous generators provide short-circuit capacity and voltage support. Due to this premise, these methods are unsuitable for renewables delivery systems with voltage source converter-based high voltage direct current (VSC-HVDC), where all apparatuses are power-electronic interfaces. This paper aims to respond the system strength evaluation problem in terms of small-disturbance analysis. Firstly, the sensitivity transfer function matrix of the bus voltage to the renewables multi-feed current is derived and the relationship between the voltage performance and stability is illustrated; Secondly, the generalized short-circuit ratio is extended into the renewables VSC-HVDC delivery system based on the voltage-source equivalent modeling of VSC-HVDC; Then, by combing the apparatus critical SCR and generalized short-circuit ratio, a source-grid separation method can be further proposed to quantify the system strength of such a system. The proposed method can assess the static voltage stability margin or small-disturbance synchronous stability margin at the operating point and determine the critical bus of system strength and the optimization path of system strength improvement. Finally, the proposed method is verified by simulation in multiple wind plants with VSC-HVDC.

• 来自： 辛焕海
• 分类： 动力与电气工程 >> 电气工程
• 投稿状态： 正在评审中
• 引用： ChinaXiv:202304.00876 (或此版本 ChinaXiv:202304.00876V2)
  DOI:10.12074/202304.00876V2
  CSTR:32003.36.ChinaXiv.202304.00876.V2
• 推荐引用方式： 马富艺龙,辛焕海,刘晨曦,李诗旸,袁辉,代江.(2023).新能源基地柔性直流送出系统小扰动强度评估方法.中国科学院科技论文预发布平台.doi:10.12074/202304.00876V2 (点此复制)