The Application Of High-Voltage Series Compensation Installation In Zhongwei Electric Grid

So far there is no agreed definite of "Power quality" in the world,from a broad point of view refers to the quality of power supply,including voltage quality,current quality,power quality and power quality.A working group of IEC gives a definition of the power supply angle of the system.The power quality is the physical characteristic of the power supply device which does not interrupt and does not interfere with the user's power.Zhongwei electric power supply company 110 kilovolt Haiyuan transformer substation is the only 110 kilovoltage transformer substation in Haiyuan old urban area.But power source sole also the electric transmission is away from long,the voltage drops obviously,moreover user's 25000 kilovolt ampere transformer start and stop load brings the voltage to undulate in a big way.In this paper,in-depth analysis of Haiyuan substation power quality difference to find the cause of this problem,and compares the common compensation scheme,finally chose the series compensation installation of this plan.The poor power quality is the root cause of Haiyuan substation power line length,especially the reactance,causing serious voltage drop.Several current common voltage compensation schemes are compared and analyzed,in order to improve the Haiyuan substation power quality as the premise of the foundation,also can achieve less investment,small occupation area,simple control,high reliability requirements.Through the analysis of series compensation installation and parallel compensation installation,the dynamic compensation installation and static compensation installation are compared,and finally the series compensation installation is selected.According to the actual situation of the substation with the equipment manufacturer to improve and optimize series compensation installation,mainly to solve the residual pressure ratio caused by Zinc Oxide valve is easy to breakdown and the operation time of the discharge switch is long,and the series compensation installation energy and running voltage are difficult to be collected on-line three problems.The dynamic debugging and artificial short-circuit test,to verify the reliability of its operation;the 110 thousand volt three-phase voltage of Haiyuan substation is improved by more than 3% after the series compensation installation be put into operation,also 110 thousand volt line loss of Xinhai was reduced by 6.5%;the series compensation installation can according to the variation of the current real-time tracking compensation,improve voltage quality and reduce voltage fluctuation,to improve the quality of the original intention of Haiyuan substation.