Microprocessor-based reclosing to coordinate fuse and recloser in a system with high penetration of distributed generation

Coordination between reclosing devices (recloser) and fuse has been traditionally done in radial power distribution systems. With increasing penetration of distributed generation, the system loses its radial nature and this coordination may not hold. This paper identifies this problem using illustrative coordination graphs. An actual system is then analyzed to find out new performance requirements from the recloser to be able to coordinate with the fuse in the new system configuration. It is shown that traditional reclosers are unable to meet these requirements. It is further shown that microprocessor-based reclosers are fully competent to meet all requirements. As an example, one such actual recloser is used to successfully coordinate with a fuse under worst possible fault conditions. A method to choose recloser curves to achieve coordination is also stated. Finally, the system is simulated on PSCAD/EMTDC/sup (R)/ software and it is proved that the recloser curves chosen in the analysis holds perfectly well in operation.

I. Introduction

Coordination between fuse and recloser has been successfully done in power distribution system [1]. With the advent of Distributed Generation (DG) however, the system would lose its radial nature. Depending on size, placement and type of DG, the coordination may or may not hold [2]. This paper begins with a description of how recloser-fuse coordination has traditionally been done in radial distribution systems and how it would be affected by penetration of DG. The paper then considers an actual system for example, identifies worst fault conditions for coordination to be lost in presence of DG and lists the requirements from a recloser to successfully coordinate with fuse in such conditions. It concludes that conventional reclosers are unable to meet these requirements whereas microprocessor-based reclosers are. The coordination procedure of microprocessor-based recloser is clearly defined. For illustrating the capability of microprocessor-based reclosers, one such ABB make recloser is considered in the example system and successfully coordinated under worst conditions. The paper then describes simulation of the example system with ABB recloser. The results obtained through simulation confirm that the settings selected theoretically hold well. In the end, some assumptions made during analysis are justified and it is shown that the suggested solution is general. Paper ends with conclusions. Data of the example system used is provided in appendix.