COVER STORY be significantly tightened. For the next step towards 50% brake thermal efficiency, a new generation of technology packages is in development, including pre-chamber spark ignition and ultra-high-pressure injection. The aim is to allow high compression ratio in the whole map while suppressing knock. One approach to achieve that is a reduction of the charge-air temperature close to ambient temperature, by use of a two-stage e-supercharger with dual intercooling. A modular charging concept including electrified components such as e-superchargers and e-turbos enables optimized use of electric energy in the hybrid powertrain. For acceleration utilizing the thermodynamic amplification (electric energy is utilized to compress air and/or spin up the TC) rather than direct electric power, the battery can be reduced in size without loss of vehicle performance. With an electrified powertrain supplementing engine torque at low engine speed, the exhaust-gas turbocharger systems can be rematched with focus on the high-speed area. This extends the potential application of each charging technology towards higher specific power, leading to a more cost-effective overall package. Table 1 shows variants in each power class based on current-production TGDI technology base and the potential for efficiency improvement with application of the above technologies. By applying the above-mentioned technology elements, the full range of ICE power can be covered by an engine family based on a turbocharged in-line 4-cylinder with about 2.0L displacement and specific power ratings from 70 to 120kW/L. Modular ICE technology packages An ICE engine family with modular components is proposed to avoid developing a dedicated base engine for each application. As well as a significant cost advantage due to higher component production volumes, this approach gives high flexibility considering uncertain future volume distributions. This approach has been proposed before and implemented by several OEMs in production. The concept is now adapted and extended to include variation based on the degree of electrification. The basic engine architecture has been laid out from the outset to minimize mechanical losses of the base engine: * long stroke (Stroke/Bore > 1.2) * crankshaft offset 12~15% of stroke * long conrod (L/r > 3.3) * minimization of bore distortion by structural * optimization and shape honing * valvetrain with low friction (RFF+HLA) * minimized diameter of main bearings * demand-controlled piston cooling jets * split cooling (separate cooling circuits for cylinder head and block) * chain-driven oil pump, pressure and volume flow is demand-controlled XGL Family Ultra-low Loss Power Inductors * The industry's lowest DCR and ultra-low AC losses across a wide frequency range * Available in a variety of sizes with inductance values from 82 to 8.2 nH to 47 μH * Current ratings up to 43 A with soft saturation * AEC-Q200 Grade 1 (-40°C to +125°C) with no thermal aging - perfect for high-temp applications Free Samples @ coilcraft.com AUTOMOTIVE ENGINEERING Free Info at http://info.hotims.com/79440-713 April 2021 23http://info.hotims.com/79440-713 http://info.hotims.com/79440-713