引用本文: | 林莉,罗皓,杨仕燕,贾源琦,汪莎莎.基于节点电动机最大自起动量的配电网低压减载[J].电力系统保护与控制,2020,48(9):77-87.[点击复制] |
LIN Li,LUO Hao,YANG Shiyan,JIA Yuanqi,WANG Shasha.An under voltage load shedding method for distribution network based on maximum self-starting amount configuration of node motor[J].Power System Protection and Control,2020,48(9):77-87[点击复制] |
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摘要: |
低压减载是电力系统安全稳定第三道防线的重要组成部分,而减载方案是低压减载的重要研究内容。感应电动机是造成电网电压崩溃的主要因素,也是低压减载的主要负荷。基于配电网及感应电动机有功特性、无功特性、转子运动方程等在Matlab搭建模型进行时域仿真分析。结果表明低压减载后的电网存在感应电动机的自起动过程,且以感应电动机为减载对象时,自起动的最大允许量与最小减载量有紧密联系。从而提出一种基于节点电动机最大自起动量的减载量整定计算方法以及减载策略。即通过不同初始转速下的节点电动机最大自起动量计算出每轮减载量,考虑减载速度对电压稳定性的影响,可在每轮减载中引入基于电压变化率的加速判据,实现有选择性地加速切除负荷。最后对传统减载策略和所提减载策略进行对比仿真,验证了所提减载方案在保证节点电压快速稳定的同时可实现对减载量的有效控制,从而保证了系统和重要电动机负荷的安全稳定运行。 |
关键词: 低压减载 感应电动机 减载量 节点电动机最大自起动量 |
DOI:10.19783/j.cnki.pspc.190733 |
投稿时间:2019-06-26修订日期:2019-08-29 |
基金项目:国家自然科学基金项目资助(50807055) |
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An under voltage load shedding method for distribution network based on maximum self-starting amount configuration of node motor |
LIN Li,LUO Hao,YANG Shiyan,JIA Yuanqi,WANG Shasha |
(State Key Laboratory of Transmission Equipment & System Security and New Technology Chongqing University, Chongqing 400044, China;Nuclear Power Institute of China, Chengdu 610213, China) |
Abstract: |
The Under Voltage Load Shedding (UVLS) is an important part of the third line of defense for power system safety and stability, and a load shedding scheme is an important part of research. Induction motors are the main cause of grid voltage collapse and the main load of under voltage load shedding. Based on distribution network and the active features, reactive features and rotor motion equations of induction motor, a time-domain simulation by a Matlab construction model shows that the induction motor self-starts after under voltage load shedding. When taking the induction motor as a load shedding object, the maximum allowable amount of self-starting is closely related to the minimum load reduction. A method for calculating the load shedding based on maximum self-starting amount configuration of the node motor is proposed. The load reduction per wheel is calculated by the maximum self-starting amount of the node motor at different initial rotational speeds. Considering the effect of load shedding speed on voltage stability, an acceleration criterion based on voltage change rate can be introduced in each round of load shedding, so as to selectively accelerate the removal load. Finally, the traditional and the proposed load shedding strategy are simulated and compared. The proposed method can effectively control the load shedding and ensure that the node voltage stabilizes rapidly, thus ensuring the safe and stable operation of the system and important motor loads. This work is supported by National Natural Science Foundation of China (No. 50807055). |
Key words: under voltage load shedding induction motors load shedding maximum self-starting amount configuration of node motor |