基于直流侧电容最小化的无功补偿技术及其控制策略研究  

Research on Reactive Power Compensation Technology and Its Control Strtategy Based on Minimization of DC-side Capacitance

作　　者：程苗苗[1] 郑月松 程龙 龚文兰 甘通 CHENG Miaomiao;ZHENG Yuesong;CHENG Long;GONG Wenlan;GAN Tong(College of Electrical and Information Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学电气与信息工程学院,长沙410082

出　　处：《电力系统及其自动化学报》2019年第12期1-9,共9页Proceedings of the CSU-EPSA

基　　金：国家自然科学基金资助项目(51777063);湖南省科技计划资助项目(2015WK3004)。

摘　　要：传统的静止同步补偿器为了保证直流侧电压恒定,一般采用较大的直流电容,在单相系统中尤为如此。基于此,本文提出了一种新型桥式结构无功补偿技术,允许直流侧电压大幅度波动,从而减小所需直流侧电容的大小。首先分析了不同无功输出时直流侧电容电压理想波形,并以此来修正三角载波的轮廓,提出了直流侧电压波动条件下的脉冲调制方法。其次分析了每个周期内电容电压波动幅度以及直流偏置量,提出了直流侧电压波形直接控制策略。仿真表明,所提出的控制策略实现了对负载扰动的快速无功补偿,保证系统的稳定运行。和其他技术相比,该技术具有直流侧电容小、电流谐波含量小、响应速度快的优点。Larger DC capacitors are generally used in the conventional static synchronous compensators to ensure a constant DC-side voltage,especially in the single-phase systems.On this basis,a novel type of bridge-structure reactive power compensation technology is proposed in this paper,which allows the DC-side voltage to fluctuate greatly and thus reduces the size of the required DC-side capacitor.First,the ideal waveform of the DC-side capacitor voltage for different reactive outputs is analyzed,according to which the outline of triangular carriers is corrected,and a pulse width modulation(PWM)method under the condition of DC-side voltage fluctuations is proposed.Second,the voltage fluctuation amplitude and DC offset in each cycle are analyzed,and a direct control strategy for the DC-side voltage waveform is proposed.Simulation results show that the proposed control strategy achieves rapid reactive power compensation for load disturbances and ensures the system’s stable operation.Compared with other technologies,this technology has advantages of small DC-side capacitance,less harmonic content in current,and rapid response speed.

关 键 词：静态同步补偿器 直流侧电压控制 无功补偿 脉冲宽度调制 

分 类 号：TM721[电气工程—电力系统及自动化]