Transformer & Switchgear PD Monitoring

Minimize the Risk of In Service Failure
During the last few decades, maintenance professionals have grown to appreciate the importance of monitoring medium voltage (4 kV to 28 kV) metal enclosed bus. Despite best efforts by manufacturers in the design of bus for indoor and outdoor applications, switchgear is not immune to aging and degradation mechanisms, particularly in industrial environments. Failure investigations reveal the link to electrical tracking between phases or phase-to-ground, and across non-metallic insulating components that support the bus.

The failure process involves contaminants (pollution) and moisture condensation. Accumulation of partly conductive airborne particles on the insulation surface results in the flow of capacitive currents that lead to discharges, and subsequently to the carbonization of organic components of the contaminants. Furthermore, poorly cast current transformers (CTs) and potential transformers (PTs) may have internal insulation voids. These voids result in partial discharge (PD) activity that will eventually bore a hole through the insulation and result in a failure to ground.

Improve Predictive Maintenance Program for your Switchgear
Traditional off-line methods of monitoring switchgear for PD activity require considerable investment (e.g. an expert to perform the measurement during scheduled outages). The techniques developed by Iris Power for motor and generator PD monitoring have now been extended to provide cost effective and reliable monitoring systems for metal clad switchgear and bus. The advantages to a maintenance department seeking to enhance reliability are as follows:
Low testing costs.

Once the sensors are installed, maintenance personnel perform periodic measurements during normal operation. In the case of a continuous monitor, the alarm levels are set to provide a warning of increasing PD activity.

Iris Power can provide support to assist in the installation and calibration of systems (if requested), and to help plan your outage by identifying the section(s) of the switchgear or bus duct that are at risk and require corrective action(s).

Trending of data and support with interpretation from Iris.
The instrumentation and hardware required to perform on-line PD testing on large rotating machines (i.e. motors and generators) is compatible with that required for bus monitoring. Hence, if your plant already owns the Iris TGAB technology, you can use the same test equipment and procedures for bus monitoring, improving the return on your investment.

What needs to be done to start monitoring PD on switchgear?
To find out what needs to be done to start monitoring PD on switchgear contact IRIS Power.

Flaw Testing for Power Generation

Ultrasonic Testing
Ultrasonic gages are commonly used in both fossil and nuclear power plants for measuring and documenting the effects of corrosion and erosion on steam boiler tubes, and also for measuring the thickness of the internal oxide buildup that limits tube life. In-service cracking in pipes, boiler tubes, steam lines, and reactor vessels can be identified with ultrasonic flaw detectors and phased array systems, which can also be used for locating cracking in generator turbine blades and rotors.

Eddy Current Testing
Eddy current technology is important to the power generation industry, particularly for the inspection of tube bundles used in the cooling process. The bundles being inspected can include many thousands of tubes, all requiring inspection, analyzing and cataloging. With projects like these, the eddy current technology is coupled with complex inspection recording programs like Carto, which allows the operators to complete the tube inspection and record the results for each tube and compile these results into a simple and easy-to-read report.

Remote Visual Inspection
RVI helps engineers get to the heart of problems quickly and easily, by checking for pitting, cracking, corrosion, erosion, weld and other defects, thus minimizing downtime and optimizing planned maintenance. If access to plant is via ladders, catwalks and into cramped spaces, portability is obviously important.

Olympus Industrial has a wide selection of lightweight, compact, yet versatile inspection systems, to suit most industrial environments and products, providing high resolution imaging in compact and mobile packages, where portability is enhanced with battery operation.

for more, visit http://www.olympus-ims.com