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Issue link: https://coal.epubxp.com/i/131326
o p e r at i n g i d e a s Genset Powers Rope Shovels During Pit-to-pit Moves Teck Coal replaced its motivator with one powered by an MTU Onsite Energy genset. Teck Coal operates some of the largest coal mines in North America and uses a mining or shovel motivator for mobile power. The existing 30-year-old motivator was underpowered and frequently in need of maintenance. Downtime costs were significant. To solve the problem, a local power products supplier designed an innovative replacement specific to the mine's needs that relies on a state-of-theart generator set from MTU Onsite Energy. All of Teck's Elk Valley sites share a single motivator. Until recently, this motivator was a long-serving unit that had finally become outdated. "The old motivator was sufficient for some of our older shovels, but it was severely underpowered for a lot of our new shovels," said Mehul Joshi, P.Eng., electrical engineer, Teck Coal. "It ran at 1,400 kW, and whenever we tried to move it, the breaker would trip, sometimes as many as four or five times during a move." The old motivator created other problems as well. Dirt and grime from the engine covered the electronic control equipment, a problem that created additional maintenance and required frequent equipment replacements. Plus, the interior was cramped and had only one exit. A key requirement for the new mining motivator was that it meet U.S. EPA Tier 2 emissions standards. Recognizing that mining is an energy intensive business, Teck has committed to short- and longterm goals that improve energy efficiency and reduce greenhouse gas emissions. 44 www.coalage.com To meet its goals for an efficient and powerful mining motivator, Joshi and his engineering team worked with Cullen Diesel Power Ltd., Vancouver, the local MTU Onsite Energy distributor, to design a motivator specific to Teck's needs. "Cullen Diesel has worked with Teck for about 40 years," said Ethan Baily, a Cullen Diesel generator sales representative who worked on the new motivator design. MTU Onsite Energy gensets supply backup building power at various mine sites, while MTU engines power several of Teck's mine trucks. The power source in the new motivator is an MTU Onsite Energy generator set that includes an MTU 20V 4000 G83L engine, which meets EPA Tier 2 emission standards in accordance with Teck's specifications. The generator set's power output is rated at 7,200 volts and 2,575 kW at an elevation of 1,300 m (Teck Coal mines are in the lower elevations of the Rocky Mountains). "We had to make sure the motivator would give the shovels ample power to run without stalling out at the high elevations," said Baily. The new motivator is about 130% more powerful than the old one—and more than capable of meeting the 1,434 kW peak power needs of Teck's newest shovels. The rope shovels' AC and DC drive systems can induce large amounts of harmonic distortion, so Cullen Diesel and MTU Onsite Energy designed a custom alternator that could handle the drive motors' high levels of harmonic distortion and still maintain required output. This slightly oversized device has a rated capacity of 3,000 kW at 105°C rise. While in operation at mine sites, a Western Star 6900XD off-highway truck pulls the trailer. But the motivator also needs to travel on public roads to get to whichever Teck mine in the area requires its services. The power source is an MTU 20V 4000 G83L engine, which is EPA Tier 2 compliant. March 2013