基于电压型换流器电网间同期并列仿真研究  

Simulation Research on Synchronization Parallel Between Grids Through VSC

作　　者：刘家军[1] 姚李孝[1] 吴添森[1] 闫泊[1] 刘博[1] 

机构地区：[1]西安理工大学水利水电学院,西安710048

出　　处：《系统仿真学报》2011年第3期528-535,共8页Journal of System Simulation

基　　金：国家自然科学基金项目(51077109)

摘　　要：就电压型换流器用于实现电网间同期并列进行了仿真研究。该方法是以电力系统的有功功率-频率理论和无功功率-电压理论为理论依据,从系统负荷的角度出发,通过改变系统负荷的有功功率和无功功率的大小达到调整频率差和电压差的目的,有别于现有的调整发电机转速和励磁进行调频和调压的方法。用该方法解决了电网间同期并列时,变电站无法调整频率差和电压差的问题。变电站运用该技术,配合调度和调频电厂,在待并网电网间实现功率传递可加快并网速度,缩短并网的时间、提高并网的自动化程度。仿真软件,对差频并网的两种情况即频率和电压两者都高的情况和频率低而电压高的情况通过PSCAD/EMTDC进行了仿真。仿真结果表明通过背靠背电压源型换流器在待并列两侧系统间进行有功功率和无功功率的传递可以调整两侧系统的频率差、电压差和相角差,使两侧系统快速满足同期并列条件,完成并列操作。A method to use Voltage Source Converter（VSC） in Synchronization between grid was proposed s,which is based on the principle of p-f and q-u from the point of the power system load,and adjusted frequency difference and voltage difference by changing the active power and reactive power of the system load.This method verified from existing methods which revised the generator speed and excitation to realize frequency modulation and voltage modulation,it solved a problem that substation could not adjust frequency difference and voltage difference while synchronous parallel operation between grids.Substations with this technology,coordinate with power dispatching centre and frequency-modulated station,may accelerate the synchronism,shorten its period and increase its automation degree through power exchange between the waiting synchronous grids.It simulated the whole process of different frequency synchronism and same frequency synchronism by PSCAD/EMTDC,both the frequency and voltage higher and the frequency lower while the voltage higher was simulated.The simulation indicates that active power and reactive power exchange through back-to-back VSC can adjust frequency difference,voltage difference and phase angle difference on the two sides of system.Thus it satisfies the synchronous condition quickly and accomplishes synchronism rapidly.

关 键 词：换流器 同期并列 功率传递 仿真 

分 类 号：TM761[电气工程—电力系统及自动化]