基于空间矢量调制的静止无功发生器在不平衡系统补偿中的应用研究
摘要
静止无功发生器（ASVG）是柔性交流输电系统中的一种重要的控制器，在国内外电力系统中均已有应用实例。在迄今为止的应用和研究中，侧重于考虑静止无功发生器补偿系统的无功功率或阻尼系统振荡的功能。本文提出静止无功发生器还具有抑制谐波和滤除负序、零序电流的能力，从而可以用于对三相四线制不平衡系统同时进行无功补偿和有害电流滤除。本文研究推导了三维电压空间矢量调制（3D SVPWM）算法，以其作为静止无功发生器的控制方法，进行了仿真研究。本文的主要工作和结论如下：
通过对现有ASVG主电路结构的对比分析，针对不平衡电力系统的补偿要求，提出以四桥臂变流器作为ASVG的主电路。本文建立了四桥臂ASVG的动态模型，以此作为参考电流转化为参考电压的依据；讨论了模型主要参数的选取原则；确定了以ip-iq法作为参考电流的检测方法。
由于电压空间矢量调制（SVPWM）具有动态响应速度快、直流侧电压利用率高以及便于数字化控制等优点，故以此作为ASVG的控制方法。本文推导了适用于四桥臂变流器的三维空间矢量调制算法。
利用Saber仿真软件的MAST语言，编制了ASVG的检测模块和3D SVPWM 控制模块，并对一个不平衡超高压（500kv）输电系统进行了仿真研究。仿真结果证明基于空间矢量调制的ASVG既能够补偿不平衡系统的无功功率，同时又能够有效地滤除系统中的谐波、负序和零序等有害电流。
本文还对一种极端的不平衡情况，即两相运行，进行了仿真研究，此时系统中的有害电流能够被ASVG滤除。这表明本文所提出的ASVG方案可以用以实现超高压输电线的非全相运行。
Advanced static Var Generator (ASVG) is an important FACTS controller, which has applied in power networks home and board. So far, however, people mainly paid their attention to those functions of ASVG , such as compensating reactive power or damping surge of power system. This paper brings forward that ASVG is capable of compensating harmonic, negative sequence and zero sequence currents. So ASVG can synchronously compensate the reactive current and harmful currents in three-phase four-wire unbalanced system. The algorithm of three Dimensions voltage Space Vector Modulation that controls the ASVG is developed. In this paper, the simulation is completed.
The main works and conclusions in this paper are as follows:
For compensating unbalanced power system,through comparing accustomed structures of main circuit, the main circuit of ASVG advanced in this paper is selected for the first time as a converter with four legs. The dynamic model of ASVG is established, which is regard as bases of transforming the reference currents to the reference voltage. Principle of selecting main model parameters is discussed. Based on the ip-iq method, the reference current signals are detected from load currents.
Space Vector Modulation technology with many advantages relative to SPWM, such as nice dynamic response ability, high utilization ratio of DC bus voltage,and convenience of composing digital control system, is adopted to control the ASVG . In this paper, the algorithm of three Dimensions voltage Space Vector Modulation applicable to converter with four legs is developed .
Using MAST language of the SABER software, the detection module and 3D SVPWM module are programmed. Simulation on a super high voltage (500kv) unbalanced power transmission system is processed. The results indicate that ASVG not only can compensate reactive currents, but also can effectively filter the harmonic currents, negative sequence currents and zero sequence currents.
As one of extremely unbalanced case, operating in two phases is also researched in this paper. In this case, the harmful currents in system can be filtered. It is showed that the ASVG advanced in this paper can realize operating in two phases in high voltage transmission through .
通过对现有ASVG主电路结构的对比分析，针对不平衡电力系统的补偿要求，提出以四桥臂变流器作为ASVG的主电路。本文建立了四桥臂ASVG的动态模型，以此作为参考电流转化为参考电压的依据；讨论了模型主要参数的选取原则；确定了以ip-iq法作为参考电流的检测方法。
由于电压空间矢量调制（SVPWM）具有动态响应速度快、直流侧电压利用率高以及便于数字化控制等优点，故以此作为ASVG的控制方法。本文推导了适用于四桥臂变流器的三维空间矢量调制算法。
利用Saber仿真软件的MAST语言，编制了ASVG的检测模块和3D SVPWM 控制模块，并对一个不平衡超高压（500kv）输电系统进行了仿真研究。仿真结果证明基于空间矢量调制的ASVG既能够补偿不平衡系统的无功功率，同时又能够有效地滤除系统中的谐波、负序和零序等有害电流。
本文还对一种极端的不平衡情况，即两相运行，进行了仿真研究，此时系统中的有害电流能够被ASVG滤除。这表明本文所提出的ASVG方案可以用以实现超高压输电线的非全相运行。
Advanced static Var Generator (ASVG) is an important FACTS controller, which has applied in power networks home and board. So far, however, people mainly paid their attention to those functions of ASVG , such as compensating reactive power or damping surge of power system. This paper brings forward that ASVG is capable of compensating harmonic, negative sequence and zero sequence currents. So ASVG can synchronously compensate the reactive current and harmful currents in three-phase four-wire unbalanced system. The algorithm of three Dimensions voltage Space Vector Modulation that controls the ASVG is developed. In this paper, the simulation is completed.
The main works and conclusions in this paper are as follows:
For compensating unbalanced power system,through comparing accustomed structures of main circuit, the main circuit of ASVG advanced in this paper is selected for the first time as a converter with four legs. The dynamic model of ASVG is established, which is regard as bases of transforming the reference currents to the reference voltage. Principle of selecting main model parameters is discussed. Based on the ip-iq method, the reference current signals are detected from load currents.
Space Vector Modulation technology with many advantages relative to SPWM, such as nice dynamic response ability, high utilization ratio of DC bus voltage,and convenience of composing digital control system, is adopted to control the ASVG . In this paper, the algorithm of three Dimensions voltage Space Vector Modulation applicable to converter with four legs is developed .
Using MAST language of the SABER software, the detection module and 3D SVPWM module are programmed. Simulation on a super high voltage (500kv) unbalanced power transmission system is processed. The results indicate that ASVG not only can compensate reactive currents, but also can effectively filter the harmonic currents, negative sequence currents and zero sequence currents.
As one of extremely unbalanced case, operating in two phases is also researched in this paper. In this case, the harmful currents in system can be filtered. It is showed that the ASVG advanced in this paper can realize operating in two phases in high voltage transmission through .
引文
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[2] 胡兆先，方燕平. 我国经济发展与电力需求趋势分析. 中国电力，2000（8）：6-9.
[3] 何大愚. 柔性交流输电控制器及对我国开发应用的建议. 电网技术，1996，20（7）：2-8.
[4] 郑健超. 电力前沿技术的现状和前景. 中国电力，1999第10期：9-14.
[5] O.A.Ciniglio, D.P.Carroll. Improved Power Transfer During Single Pole Switching: A Symmetrical Sequence Filtering Approach. IEEE Trans. on Power Delivery, 1993, 1, pp.454-460
[6] 刘刚. 超高压输电线非全相运行时负序电流消除方法的研究, 重庆大学硕士论文, 1997, 5
[7] 秦梅. 新型统一潮流控制器在超高压输电线路非全相运行中应用的研究. 重庆大学硕士论文，2000，5
[8] 武守远，周孝信，赵贺 等. 电力系统最新技术──灵活交流输电系统的发展及研究. 电网技术，1996，20（5）：1-3.
[9] 王兆安,杨君,刘进军. 谐波抑制和无功功率补偿. 机械工业出版社,1998,9
[10] C.W.Edwards, K.E.Mattern, P.R.Nannery etc. Advanced Static Var Generator Employing GTO Thyristors. IEEE Transactions on Power Delivery, 1988, 3(4): 1622-1627.
[11] C.Schauder, M.Gernhardt, E.Stacey etc. Development of a ±100MVAR Static Condenser for Voltage Control of Transmission Systems. IEEE Transactions on Power Delivery, 1995, 10(3): 1486-1496.
[12] 陈建业,王仲鸿,韩英铎 等. 新型静止无功发生器(ASVG)的研究现状. 清华大学学报(自然科学版), 1997, 37(7): 7-12.
[13] 姜齐荣, 王强, 韩英铎 等. 新型静止无功发生器(ASVG)装置的建模及控制.
清华大学学报(自然科学版),1997, 37(7): 21-25.
[14] 马晓军, 姜齐荣, 陈建业 等. 不对称系统的设计参数对STATCOM 性能的影响. 清华大学学报(自然科学版),2000, 40(7): 23-26.
[15] 王仲鸿, 姜齐荣, 沈东. 关于新型静止无功发生器模型参数及暂态控制模型选择的讨论. 电力系统自动化, 1999, 23(24): 43-45.
[16] 梁旭, 刘文华, 陈建业. 基于多重化逆变器的静止无功发生器直流侧电流分析. 电工技术学报, 2000, 15(1): 52-56.
[17] 刘文华 梁旭, 沈东 等. 新型静止无功发生器的GTO保护. 清华大学学报(自然科学版), 1997, 37(7): 17-20.
[18] 梁旭, 刘文华, 陈建业 等. 采用GTO的±300kvar新型静止无功发生器. 清华大学学报(自
然科学版), 1997, 37(7): 13-16.
[19] 刘文华, 宋强,王志泳 等. ±20Mvar Statcom 装置他励启动整流器.电力电子技术,2000,第3期: 1-6.
[20] 高航, 陈希正, 许沛丰 等. ASVG工业化装置在电力系统中的应用. 中国电力, 2000, 33(2): 33-35.
[21] 白恺, 李隆年. ASVG几种典型主回路结构的谐波分析及比较. 清华大学学报(自然科学版), 1997, 37(7): 30-34.
[22] 孙元章, 杨志平, 王志芳 等. ASVG非线性控制及其对电压稳定性改善的研究. 电力系统自动化, 1996, 20(6): 21-26.
[23] 陈巍, 吴捷. 静止无功发生器递归神经网络多目标监督控制. 电力系统自动化, 1999, 23(7): 15-19.
[24]B.N.Singh,A.Chandra,K.Al-Haddad. DSP-based indirect-current-controlled STAT-COM,Part1:Evaluation of current control techniques. IEE procelectr power Ap-pl,2000,147(2).
[25] B.N.Singh,A.Chandra,K.Al-Haddad. DSP-based indirect-current-controlled STA-TCOM,Part 2:Multi-functional capabilities. IEE procelectr power Appl,2000,147(2).
[26] 王强, 姜齐荣, 姜旭峰 等. 20Mvar静止无功发生器(SVG)控制器的设计. 电力电子技术, 1999, 第6期: 1-3,10.
[27] 姜齐荣, 刘文华, 韩英铎 等. ±20Mvar STATCOM 控制器设计.电力系统自动化, 2000,24(23): 24-28.
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