Optimization Design of Optical Current Sensor with Magnetic Concentrator Ring for Gas Insulated Switchgear

To improve the flexibility and practicality of the magnetic concentrator ring optical current sensor (OCS), the extra-hoop OCS scheme with large size magnetic concentrator ring and double-incision structure was proposed. The sensing character of the extra-hoop OCS was analyzed and the results showed that the double-incision structure, leakage flux and permeability are three key factors affect the sensitivity and the linearity of the extra-hoop OCS and there are specific relations between them. The magnetic circuit model and sensing model were established, and the optimum scheme was designed. The precision of the designed extra-hoop OCS reaches the 0.2-class.