VSC-HVDC的动态相量建模和PLL研究

发布时间：2018-11-18 12:51

【摘要】：柔性高压直流输电系统(VSC-HVDC)是基于全控型器件组成的电压源换流器(VSC)的一种高压直流输电系统,它的两个基本特征就是使用了全控型器件和脉宽调制(PWM)技术。VSC-HVDC系统电磁暂态模型十分精细,但是并不适用于大型网络的仿真,机电暂态模型是基于“准稳态假定”的,适合大型网络的仿真。但是,随着越来越多的FACTS元件广泛地应用于电力系统中,系统中出现了很多快速持续的动态变化,而这种变化是不满足准稳态假定的,因而此时机电暂态模型是不够精确的。动态相量分析法是基于傅里叶变换的一种建模方法,它不受限于准稳态假定,可以很好地分析含有大量电力电子器件的VSC-HVDC系统。 本文介绍了动态相量分析法的理论基础,着重分析了传统相量的局限性和错误,证明了动态相量法的准确性。文中介绍了VSC-HVDC的基本机构和特性,并使用开关函数法建立了时域范围内的详细电磁暂态模型。文章接下来分别建立了VSC-HVDC准稳态模型和动态相量模型,并分别作了仿真验证,证明了动态相量模型准确度与电磁暂态十分接近,但是仿真速度却快很多。在含有大量电力电子器件的系统中,考虑相量的动态变化,动态相量模型比准稳态模型要精确。文中介绍了VSC-HVDC的控制系统,换流站级控制系统是整个控制系统的核心,本文重点介绍了换流站级控制系统,控制方法包括间接电流控制法和直接电流控制法,然后提出了一种三相不平衡条件下基于积分的PLL控制方法,可以使VSC-HVDC控制系统更加精确。
[Abstract]:Flexible high voltage direct current transmission system (VSC-HVDC) is a kind of HVDC transmission system based on (VSC) of voltage source converter, which is composed of full control devices. Its two basic characteristics are the use of full control devices and pulse width modulation (PWM) technology. The electromagnetic transient model of VSC-HVDC system is very fine, but it is not suitable for the simulation of large networks. The electromechanical transient model is based on the quasi-steady state assumption and is suitable for the simulation of large-scale networks. However, with more and more FACTS components widely used in power systems, there are many rapid and sustained dynamic changes in the system, which is not satisfied with the quasi-steady state assumptions, so the electromechanical transient model is not accurate enough. Dynamic phasor analysis is a modeling method based on Fourier transform. It is not limited to quasi-steady state assumption and can be used to analyze VSC-HVDC systems with a large number of power electronic devices. In this paper, the theoretical basis of dynamic phasor analysis is introduced, the limitations and errors of traditional phasor are analyzed, and the accuracy of dynamic phasor method is proved. In this paper, the basic mechanism and characteristics of VSC-HVDC are introduced, and the detailed electromagnetic transient model in time domain is established by switching function method. Then the quasi-steady state model and dynamic phasor model of VSC-HVDC are established, and the simulation results show that the accuracy of dynamic phasor model is very close to that of electromagnetic transient state, but the simulation speed is much faster. The dynamic phasor model is more accurate than the quasi-steady model in the system with a large number of power electronic devices considering the dynamic variation of the phasor. This paper introduces the control system of VSC-HVDC, the converter station level control system is the core of the whole control system. This paper mainly introduces the converter station level control system, which includes indirect current control method and direct current control method. Then a PLL control method based on integral under the condition of three-phase unbalance is proposed, which can make the VSC-HVDC control system more accurate.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM721.1

【参考文献】

相关期刊论文 前10条

1 何瑞文,蔡泽祥;基于动态相量法的电力电子变换器的模型与仿真分析[J];电工电能新技术;2004年03期

2 陈谦,唐国庆,胡铭;采用dq0坐标的VSC-HVDC稳态模型与控制器设计[J];电力系统自动化;2004年16期

3 郑超,周孝信,李若梅;电压源换流器式高压直流输电的动态建模与暂态仿真[J];电网技术;2005年16期

4 严干贵;陈涛;穆钢;刘文华;李军徽;黄亚峰;;轻型高压直流输电系统的动态建模及非线性解耦控制[J];电网技术;2007年06期

5 叶卫华;李富鹏;王勇锋;;基于动态相量法的PWM DC/DC变换器的建模与分析方法[J];电子与封装;2011年11期

6 郑超;盛灿辉;魏强;盛浩;;VSC-HVDC输电系统的电磁暂态建模与仿真[J];高电压技术;2007年11期

7 皇甫成;汤广福;阮江军;王燕;;VSC-HVDC统一电磁暂态模型及其控制策略[J];高电压技术;2008年05期

8 姚伟;程时杰;文劲宇;;电压源型直流输电的动态相量建模与仿真[J];高电压技术;2008年06期

9 潘武略;徐政;张静;;不对称运行条件下VSC-HVDC动态相量建模[J];高电压技术;2009年07期

10 杨少坤;尹明;刘文丽;;背靠背型柔性直流输电的建模及其控制[J];华北电力大学学报(自然科学版);2007年05期

相关博士学位论文 前3条

1 鄂志君;基于动态相量理论的电力系统建模与仿真研究[D];天津大学;2008年

2 李胜;柔性直流技术在城市电网中应用研究[D];华北电力大学（北京）;2009年

3 梁海峰;柔性直流输电系统控制策略研究及其实验系统的实现[D];华北电力大学（河北）;2009年

，

本文编号：2340080