Study On The Transducer Of Ect Based On Rogowski Coil

With the increasing of electrical transmission capacity and the increasing degree as well as improving protection requirement of power system's voltage,the common current transformer will display unconquerable problems of it and can't meet the automation and digital requirement of power system.But,Electronic Current Transformer (ECT) has become a new direction of current transformers' development for its no saturation under fault current conditions, high level insulation and broad range of measurement. However, there is a long way for ECT to be widely applied, resulting from the disadvantages of its Sensor Head, including the interference of ambient temperature and external electromagnetism and the difficulty of manufacturing technic.This dissertation introduced the strong points and disadvantages of MOCT and ECT at first, then described the basicprinciple of ECT, and analysed the ECT based on Faraday mageto-optical effect and Rogowski coil. In this dissertation, mang problems were pointed out during the researching on CT. I found out the target of reaserching according to our application level.In the dissertation, the composite construction, function and operation methods of Rogowski coil were described. This dissertation mostly analysed and designed the Sensor Head of Rogowski coil. The interference of ambient temperature and extenral electromagnetism with Rogowski coil were investigated by mathematical models. The relations between relative measurement error resulting from temperature and heat distensibility coefficient of coil's framework and winding coil were carried out. The influence of electromagnetism interference on the accuracy of Rogowski coil, as well as the effect of temperature on integraph were studied. Some measures based on the above investigating results were proposed to insure the precision of Rogowski coil sensor Head, such as the selection of materials and facture methods, improvement of technics. At the same time, the dissertation disigned a new coil as the above investigating results, and improved the simulation integrator, and designed a numerical integrator circuit.In the end, this dissertaiton designed a new Rogowski coils according to the Rogowski coil's principle and structure as well as interference factors. Experiment result confirmed the correctness and availability of the refered design methods .Furthermore, a Rogowski coil Sensor Head satisfying the requirements was designed based on the above methods.