Mark CrittendenEngineering Manager Generator Repairs Division
I began my career in the energy industry in 2001 with General Electric®, where I completed the Generator Specialist program. In my time with GE® I worked in many roles, including as a generator manufacturing Production Manager, a Generator Project Leader in a generator service shop, a Project Manager in Performance Services, and as a Generator Product Line Manager. In 2018, I joined MD&A as the Generator Engineering Manager at the MD&A Turbine-Generator Repair Facility in St. Louis, Missouri.
What do you do here at MD&A?
In my role as Engineering Manager, I have a wide range of both technical and administrative responsibilities, including new product development, procedure creation, resource allocation, technical consultation, and supply chain management.
What is the most interesting challenge you have come across with a generator?
I have been exposed to a greater variety of other OEM (oOEM) generator designs in my time with MD&A than at any other point in my career. This has been a welcome challenge and has increased my knowledge of the various generator designs.
Recently, a large air-cooled generator field arrived in St. Louis for a field rewind with existing copper. Drawing from our vast experience base, MD&A developed a rewind solution for this particular generator model. Through meticulous planning and preparation, the engineering team identified the exact set of part drawings needed before the field’s arrival. The completed drawings were sent to the appropriate vendors within several days of field disassembly. This impressive turn around highlights the strengths of MD&A’s engineering team.
How is a Generator Robotic (in-situ) Inspection helpful?
A robotic in-situ generator inspection allows the customer to acquire data regarding several key components of the generator without having to remove the field. This saves the customer both time and money.
In many power plants, the layout is such that the removal of the field is very challenging. A robotic inspection provides the customer with information regarding the stator core iron and stator slot wedges during a minor inspection (with the field still in the unit), which could previously only be obtained during a major inspection (field removed).
When would you perform a stator re-wedge (wedge system upgrade)?
Stator slot wedges secure the stator bars in the slot and loose wedges can lead to excessive movement/vibration of the stator bars. Over time, this will cause the ground wall insulation to break down and can eventually lead to a ground fault.
A wedge tightness assessment is the most accurate method used to obtain data on the status of a generator’s stator slot wedges. If the results indicate that a partial or full stator re-wedge is required, it is critical for the work to be completed at the earliest possible time.
What do you like to do in your spare time?
I enjoy playing in several tennis leagues.