Survey of different sensors employed for the power transformer monitoring

The importance of the continuous service of power transformers and their role in the reliability of the power delivery has resulted in the need for various monitoring systems which utilise different electrical, mechanical, optical, chemical, and acoustic sensors to monitor the vital characteristics of the power transformer. A brief review of these sensors is attempted. First, the parameters that are normally monitored in a transformer are explained to clarify the types of sensors that are needed and their duties. Then, each sensor type is described in summary while giving proper references for further reading. Accordingly, a fast guide for practitioners researching the sensors utilised for power transformer monitoring is presented.