Acoustic Partial Discharge Detection Using Low-cost Pre-amplified Piezoelectric Transducer and Coated Optical Fiber Sensor

Partial discharges (PD) occur in high voltage equipment are considered as major problem that required to be prevented to avoid any breakdown, damage and loss from happening. In addition, this pre-breakdown phenomenon can be detected using appropriate sensors such as acoustic emission sensor. In this study, acoustic emission sensor was chosen as the method to detect the PD in high voltage insulation. Low-cost piezoelectric transducer (PZT) with pre-amplifier and optical fiber sensor (OFS) were used as a sensing device to detect PD but OFS was expected to highlight its usage towards PD detection. Development of optical fiber sensor (OFS) based on Single Mode-Multi Mode-Single Mode (SMS) structure which implementing a Multimode Interference effects (MMI) was focused on. PD measurement test was conducted according to IEC 60270 and IEC TS 62478 standards. A coated SMS based OFS was fabricated and then was used in PD measurement test. Furthermore, after implementing the pre-amplified PZT sensor and coated OFS in PD measurement test, results were compared with a measuring impedance by analyzing the Phase Resolved Partial Discharge (PRPD) patterns. From the results, all sensors can detect PD as accurately as the MI but the usage of pre-amplifier on PZT has shown a great deal of advantage in removing noises and amplifying small signal, but the SMS coated OFS has shown similar ability in detecting the PD.