Acoustic Emission Diagnostic and Monitoring of Power Transformers
Power transformers account for the largest portion of capital investment in transmission and distribution substations. Failure of a single power transformer carries a multimillion-dollar impact with a build or replacement timeline of18-24 months. Yet 53 percent of transformer failures are preventable. But what if there was a way to protect that substantial investment while safeguarding against catastrophic failure?
MISTRAS offers that answer with diagnostic and monitoring of power transformers with Acoustic Emission (AE) technology.
AE monitoring is a well-known, accepted technique to detect and locate AE signals in power transformers – it is the Silver Bullet for protecting critical capital investments by helping prevent millions of dollars in potential losses. The value of protection for system critical hardware like power transformers cannot be overstated.
Do you have a gassing transformer? Using AE diagnostic and monitoring techniques on power transformers has a host of useful and versatile functions. These functions can be utilized while keeping power transformers on- line, therefore preventing a costly outage and saving customers lost revenue. Also, AE can not only provide an accurate assessment of your equipment’s condition during on-line testing, but also can monitor your transformer during special operating conditions like overload, solar storms, commissioning, etc. It can even determine under which operating conditions a fault is active.
Youcan use acoustic emission for all these functionsand more!
Advantages of this techniqueinclude:
• Applied on-line
• Non-invasive
• More sensitive than electric methods for on-site tests
• Locate the source(s) in a two and three- dimensional plot
• Can be used atmanufacturer’s facilities or repair/refurbishment shops to locate a defect when detected by electric methods
• The performance of this technique is enhanced when used in conjunction with Dissolved Gas Analysis (DGA).
AEDetects:
• Partial discharge
• Arcing
• Hot spots
• Loose connections
• Static electrification in GSU Transformers
• Core clamping problems
• Mechanical defects
Other parameters (load current, vibration, gas monitoring data, pump current, temperature, and load tap changer motor current) are acquired along with Acoustic Emission data in order to correlate this information with the operating conditions on the transformer during the test/monitoring. A grading system provides information on the intensity of the fault. All results are compared to a database of over 1000 test subjects.
See Why Acoustic Monitoring Works http://online.electricity-today.com/doc/electricity-today/et_oct2011_digital/2011102401/#42