Electrical design of signal conditioning and signal processing circuit for Rogowski coil

• Main Author: Francis, Antony Denisha
• Other Authors: Abhisek Ukil
• Format: Theses and Dissertations
• Language: English
• Published: 2016
• Subjects: DRNTU::Engineering::Electrical and electronic engineering::Power electronics
• Online Access: http://hdl.handle.net/10356/68985
• Institution: Nanyang Technological University

This thesis deals with the detection of fault current using rogowski coil. The signal processing and signal conditioning circuit for rogowski coil is discussed. The importance of Rogowski coil in measuring fault current is required for the selection of protective devices like relays and circuit breakers. The primary use of the current sensing with the Rogowski coil in the project is for fault management studies and to design the fault algorithms for different faults accordingly for the power systems under study. Rogowski coil is evolved from solenoids and it’s a device for current detection and measurement with high accuracy. Being an air cored coil, Rogowski coil measures both alternating and high impulse currents. The coil measures the current and the output of the coil is in the form of voltage proportional to the current. The fault current is sensed with the different models of the coil and feasibility check is discussed. Rogowski coil is mainly used for measuring alternating currents and the frequency response of the coil is higher compared to other current sensors like Current transformer, Shunt and Hall Effect sensors. Rogowski coil is not involved in measuring direct fault currents. The thesis deals in designing the models of coil for the measurement of high direct fault currents. This process also includes the involvement of real time simulator OPAL-RT from where the input signals are fed into the coil. The signal processing circuit of Rogowski coil with the communication of OPAL-RT and Rogowski coil is also dealt in the thesis. The conceptual designs are modelled using MATLAB and the current sensing circuit is analysed with the fault conditions. The performance of the coil and the system integration along with the coil is studied and the simulation results are used to verify the proposed system along with Rogowski coil models.