Automotive Design and Production

JUN 2013

Automotive Design & Production is the one media brand invested in delivering your message in print, online, via email, and in-person to the right automotive industry professionals at the right time.

Issue link: https://adp.epubxp.com/i/132123

Contents of this Issue

Navigation

Page 24 of 59

The GM Baltimore Operations (GMBO) facility is not an old plant. The 471,000sq. ft. facility has been producing transmissions and torque converters for everything from the Chevy Silverado 2500/3500 full-sized pickups to the Corvette for more than a decade. Since start of production in December 2000, GMBO has produced 1,419,038 transmissions. But an interesting thing happened a couple of years ago, when there was a ground breaking at the site in White Marsh, MD. Corporate, state, and local ofcials moved dirt for what has become an 110,500-sq. ft. building flled with a variety of equipment, from Fanuc robots (fanucrobotics.com) to Promess electromechanical servo presses (promessinc.com). The facility was set up to produce permanent-magnet electric motors (or, as Pete Savagian, GM, general director, electric drive systems engineering, says, "electric machines," as this is the nomenclature that those in the feld use) for the 2014 Chevrolet Spark EV. The motors (we admittedly aren't in the feld) produce 100 kW and 542 Nm . . . or 130 hp and 400 lb-ft of torque for the minicar that will initially be sold in California and Oregon, then make its way to markets including Canada, parts of Europe, and South Korea. And before leaving South Korea, it is interesting to note that the Spark EV and the gasoline-powered version are built in the GM plant in Changwon, South Korea. The 560-lb. lithium-ion battery pack (consisting of 336 cells) for the electric vehicle (EV) is built in Livonia, MI, by A123 Systems. And the drive system (including the motor—which was developed in Pontiac, MI) is being produced in White Marsh. This is truly a global program. Electric motor stators on an assembly line at the GM Baltimore Operations. When fnished, the 130-hp (130-kW) motors will be used in the Chevy Spark EV. p Compared with the Spark with its standard 84-hp, 1.2-liter gasoline engine, the Spark EV has a 130-hp electric motor. The EV is more aerodynamic than its kin, says Chuck Russell, Spark EV chief engineer, thanks to features including a closed front grille, aero shutters in the lower grille, diferent front and rear fascias, an underbody cover, added rocker cover, and a modifed rear spoiler. And before leaving the overview of GMBO, it is worth noting that the women and men who work there (186 hourly, 64 salaried) are not wholly unfamiliar with advanced powertrain technology: the Hybrid Two-Mode transmission that is used in GM pickups and SUVs is produced at that plant, too. Speaking of the Spark EV motor, Savagian says that its performance is comparable to those used for machine tools. Which leads to the question of why, then, is GM manufacturing these motors rather than sourcing them from companies that produce motors for machining centers and the rest? And the answer is that what's needed for EVs is diferent than the requirements for machine tools. For one thing, the EV motors must be quiet; there must be low vibrations. Clearly, this is not high on the checklist so far as factories are concerned. The EV motors provide safety-critical torque—when you're zipping along in a Spark EV on the freeway, you don't want to have your motor fail—so the levels of quality and reliability must be exceedingly high. This is not to say that quality and reliability aren't important for the motors used for machining centers, but it is of a diferent nature. Savagian says the EV motor reliability and safety requirements are more analogous to elevator motors. Importantly, because this is the auto industry, afordability is essential. This is not to say that GM is going to be the source of electric motors for all of its existing or future hybrids and EVs, be it for the Volt (which is similar to the Spark EV setup; according to Chuck Russell, Spark EV chief engineer, who also worked on the Volt, by taking advantage of learnings from the Volt— ranging from the battery to the HMI to the motor—"We were able to reduce the lead time on vehicle development") or for the eAssist that is available in a variety of its models (though eAssist uses an induction motor, not a permanent-magnet type). → 23

Articles in this issue

Links on this page

Archives of this issue

view archives of Automotive Design and Production - JUN 2013