引用本文: | 王轩,魏宏,欧朱建,等.一种抑制HVDC换相失败的STATCOM补偿方案[J].电力系统保护与控制,2018,46(5):135-142.[点击复制] |
WANG Xuan,WEI Hong,OU Zhujian,et al.A STATCOM compensation scheme for suppressing commutation failure in HVDC system[J].Power System Protection and Control,2018,46(5):135-142[点击复制] |
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摘要: |
针对高压直流输电(High Voltage Direct Current, HVDC)系统中的换相失败问题,提出一种STATCOM补偿方案。该方案将星型级联H桥STATCOM中性点直接接地,并入HVDC系统逆变端,从而具备三点优势:保留星型级联H桥STATCOM经济性高的优点;三相独立,可视为三个单相STATCOM,各相换流链独立控制,克服了传统星型级联H桥STATCOM在电网电压不平衡情况下的控制问题;利用HVDC所接入的交流电网的中性点接地的特点构成零序电流通道,不仅可以补偿谐波、正序、负序无功电流,也可以补偿零序无功电流,补偿性能较传统拓扑更为优良。详细分析了该补偿方案在HVDC中的可行性,并推导了电网电压不平衡情况下,换流链电流指令中的零序电流分量。给出了控制策略并通过PSCAD/EMTDC对所提补偿方案用于抑制HVDC换相失败的性能进行验证。 |
关键词: 高压直流输电 换相失败 STATCOM 中性点接地 零序电流 |
DOI:10.7667/PSPC170230 |
投稿时间:2017-02-21修订日期:2017-07-01 |
基金项目:国家自然科学基金(51541708);国家电网公司科技项目(52466F150008) |
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A STATCOM compensation scheme for suppressing commutation failure in HVDC system |
WANG Xuan,WEI Hong,OU Zhujian,FU Yongsheng,YU Jinsong |
(NARI Group Corporation State Grid Electric Power Research Institute Co., Ltd., Nanjing 211000, China;China EPRI Science & Technology Co., Ltd., Beijing 102200, China;School of Electrical Engineering, Shandong University, Jinan 250061, China) |
Abstract: |
This paper proposes a STATCOM compensation scheme for suppressing commutation failure in HVDC. In this scheme, the neutral-point of CHB-STATCOM with star configuration which is connected to power grid is grounded. The scheme possesses three advantages. Firstly, it reserves high economy as CHB-STATCOM with star configuration. Secondly, three phases are independent of each other, which can be considered as three single-phase STATCOMs, leading to a simple and flexible control strategy and overcoming the control problem when CHB-STATCOM with star configuration operations under unbalance grid. Thirdly, it forms zero-sequence current channel by using of characteristic of HVDC, which is the neutral-point of the AC grid connected by HVDC is directly grounded, thus it can compensate not only harmonics, positive and negative-sequence reactive power, but also zero-sequence reactive power, resulting in excellent compensatory capacity. The feasibility of the proposed scheme in HVDC is analyzed in detail. Zero-sequence current is calculated in detail under unbalanced grid condition. The control strategy is given and the simulations based on PSCAD/EMTDC are carried out to illustrate the effectiveness to suppress communication failure in HVDC. This work is supported by National Natural Science Foundation of China (No. 51541708). |
Key words: HVDC commutation failure STATCOM neutral-point grounding zero-sequence current |