High current（greater than 100 A） sensing and measurement technologies of DC

AC

and impulse are widely utilized in the power system

industry

equipment testing and scientific research. We summarized the popular current measurement techniques which are divided into four categories by their principles as follows: shunts based on Ohm’s law

AC/DC current transformers based on closed-loop feedback

open-loop current sensing technology based on magnetic field measurement

and optical current transformers based on magneto-optical effect. On the basis of a brief introduction to the basic principles

we analyzed the advantages

disadvantages

application

and key points of these current measurement technologies

and introduced the latest progress in the research. Finally

we presented the development trend and application prospects of this field.The performance improvement technology of traditional current measurement & sensing principles in wide-range temperature characteristics

high dynamic range

AC/DC mixing

high bandwidth

etc.

are still hotspots. Optical current transformers have been widely used and show unique advantages in ultra-large current measurement

however

the problems such as relatively low reliability and long-term stability need to be solved in their applications.