Engineering Application Issues Such as Polarity and Capacity Selection of Current Transformers
At present,current transformers are widely used in 10～35 kV switchgear equipment.However there are common problems in actual engineering design,including diversified polarity orientations of transformers,unclear winding definitions,improper secondary grounding,and different user requirements,which lead to secondary wiring errors and on-site undesired activation of relays.In addition,excessive capacity requirements for mutual inductors during selection and design have caused inconvenience to transformer production and cabinet installation.Hence this paper discusses the installation method of mutual inductors from the perspective of cabinet structure,and summarizes precautions in determining polarity orientation,secondary winding sequence,and wiring of the transformer.In addition,common capacity settings for measurement and protective windings are given along with their calculation methods,according to the standards for reference in design.
NETL
NSTL
万方数据
