Rogowski coil current transformer（RCT） is a kind of novel electronic current transformer.Comparing with traditional current transformer（CT）

RCT has many advantages

such as wide dynamic range

broad frequency band.On the contrary

the temperature characteristics and the long-term stability of RCT are inferior to those of CT.The all-digital design is applied to improve the performance of RCT further

including digital integrating

digital transmission

digital signal processing and digital output.That means all parts of the RCT except the sensor are digital.The accuracy test and the digital output interface test of all-digital RCT have been taken.The test results show that the all-digital designs can meet the 0.2 class accuracy and the requirements of IEC standard.