| Popis: |
With the rapid advancement in smart grid and smart cities across the world there have been great demand for smart meters and protection devices such as digital meter and microprocessor based release and protection unit. These high burden devices demand air cored current sensor with micro-VA and low level signal sensitivity. One such family of current sensor which has been widely accepted is rogowski current sensor, which suffers from various problems such as interference of external magnetic field, non uniform positioning of the start and end winding, offset and tilting of the primary conductor. Apart from this, size is a constraint in such type of sensors. The paper discloses about development of a flexible printed circuit air cored current sensor, which overcomes all the problem as said above with low level signal sensitivity and VA rating. It essentially consists of sense & cancellation coils connected in opposite polarity with respect to each other, which are printed or etched upon the flexible polymer. The secondary winding and primary conductor are in the same plane. The paper illustrates about prototype development and performance evaluation of a 300A rated current sensor. It highlights about effect of mixed signals upon performance of the sensor. |
