Study On Arc Suppression Coil Distributed Compensation For City Network With Large Capacitive Current

Because more and more cables are used in the reform of 10-35 kV system,the capacitance current of the system increasing rapidly.The original arc suppression coil capacity can not reach the compensation requirement.For the traditional centralized compensation,the capacity of the single arc suppression coil is simply increased but with the problem of adjustment range and the limit of the switch gear,and if changed to the resistance grounding mode,will have the problem of low electrical reliability and user side protection,however the distributed compensation of arc suppression coil breaks through the traditional mode of compensation capacitance current,which has the characteristics of flexible installation and convenient expansion,so it has attracted much attention and has a very broad prospects for development.Based on the PSCAD simulation software,the distributed compensation of arc suppression coil is studied.Firstly,the distribution network model containing distributed compensation of arc suppression coil is built by using PSCAD simulation software.Then,study the ground residual current of the distributed compensation device installed at the end of the fault line or the end of the non-fault line when fault taking place at the 1/4,1/2,3/4 or the end of the line.The distributed compensation capacity accounted different lead to the residual current different.The Influence of arc Reburning in arc ground when the proportion of the distributed compensation capacity in the total compensation capacity of the system is different,and the internal ratio of the distributed compensation capacity is different.The compensation scheme is put forward and compared and CDEGS software is used to evaluate the influence of the ground potential rise,the contact voltage and the step voltage on the personal safety caused by the compensation current.Finally,the grounding transformer and arc suppression coil integration device suitable for distributed compensation installation is introduced from the respect of structure and principle.The results show that : the reasonable installation position of the distributed compensation device should be located at the end of the fault frequency line,and increase the proportion of the distributed compensation capacity in the total compensation capacity of the system is helpful to the decrease of the residual current and the extinguishing of the arc and the internal ratio has no obvious effect on the compensation effect,the "multi point compensation" scheme is recommended in the present field.The operation of distributed compensation device is conducive to improving power supply reliability and reducing operation cost.The research of this paper has certain reference value for the application and promotion of the distributed compensation of arc suppression coil.