A Novel Isolation Device with High Common Mode Rejections for Power System Monitoring

The monitoring and analysis of power systems parameters by digital systems and computers are well recognized. However, these digital systems must be isolated from the power system surge and high frequency components. Designing a cost effective isolation device with high common mode rejection, that allows all the frequency components to pass, has been a challenge. The main contribution of this paper is to design a novel isolation device that exhibits a high common mode rejection and allows all the frequency components to pass through the system. The isolation device is cost effective and it is used in commercially available digital fault recorder.