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With the increasing demand for efficient & clean transport solutions, applications such as road transport vehicles, aerospace and marine are seeing a rise in electrification at a significant rate. Irrespective of industries, the main source of power that enables electrification in mobility applications like electric vehicles (EV), electric ships and electrical vertical take-off & landing (e-VTOL) is primarily a battery making it fundamentally a DC system. Fast charging solutions for EVs & e-VTOLs are also found to be DC in nature because of several advantages like ease of integration, higher efficiency, etc. Likewise, the key drivers of the electric grid are resulting in an energy transition towards renewable sources, that are also essentially DC in nature. Overall, these different business trends with their drivers appear to be converging towards DC power systems, making it pertinent.

The automotive industry has seen accelerating demand for electrified transportation. While the complexity of conventional ICE vehicles has increased, the powertrain still largely consists of a mechanical system. In contrast, vehicle architectures in electrified transportation are a complex integration of power electronics, batteries, control units, and software. This shift in system architecture impacts the entire organization during new product development, with increased focus on high power electronic components, energy management strategies, and complex algorithm development. Additionally, product development impact extends beyond the vehicle and impacts charging networks, electrical infrastructure, and communication protocols. The complex interaction between systems has a significant impact on vehicle safety, development timeline, scope, and cost.

With the advent of wide band gap semiconductor devices like SiC based MOSFETs/Diodes, there is a growing demand for utilizing electrical power instead of the conventional fuel-based power generation in both automotive and aerospace industry. In automotive/aerospace industry the focus on electrification has resulted in a need for sub-systems like inverters, power distribution units, motor controllers, DC-DC converters that actively utilize SiC based power electronics devices. To address the growing power density requirements for electronics in next generation product families, more efficient & reliable thermal management solution plays a critical role. The effective thermal management of the power electronics is also critical aspect to ensure overall system reliability. The conventional thermal management system (TMS) optimization targets heat sink/ cold plate design parameters like fin spacing, thickness, height etc. or sizing of the required cooling pump/fan.

This paper addresses Hardware-In-the-Loop modeling and simulation for Diesel aftertreatment controls system development. Lean NOx Trap (LNT) based aftertreatment system is an efficient way to reduce NOx emission from diesel engines. From control system perspective, the main challenge in aftertreatment system is to predict temperature at various locations and estimate the stored NOx in LNT. Accurate estimation of temperatures and NOx stored in the LNT will result in an efficient system control with less fuel penalty while still maintaining the emission requirements. The optimization of the controls will prolong the lifespan of the system by avoiding overheating the catalysts, and slow the progressive process of component aging. Under real world conditions, it is quite difficult and costly to test the performance of a such complex controller by using only vehicle tests and engine cells.

Steer-by-wire systems (SBW) offer the potential to enhance steering functionality by enabling features such as automatic lane keeping, park assist, variable steer ratio, and advanced vehicle dynamics control. The lack of a steering intermediate shaft significantly enhances vehicle architectural flexibility. These potential benefits led GM to include steer-by-wire technology in its next generation fuel cell demonstration vehicle, called “Sequel.” The Sequel's steer-by-wire system consists of front and rear electromechanical actuators, a torque feedback emulator for the steering wheel, and a distributed electronic control system. Redundancy of sensors, actuators, controllers, and power allows the system to be fault-tolerant. Control is provided by multiple ECU's that are linked by a fault-tolerant communication system called FlexRay. In this paper, we describe the objectives for fault tolerance and performance that were established for the Sequel.

The hybrid system for the 2007 Model Year Saturn VUE Green Line Hybrid SUV was designed to provide the fuel economy of a compact sedan, while delivering improved acceleration performance over the base vehicle, and maintaining full vehicle utility. Key elements of the hybrid powertrain are a 2.4L DOHC engine with dual cam-phasers, a modified 4-speed automatic transmission, an electric motor-generator connected to the crankshaft through a bi-directional belt-drive system, power electronics to control the motor-generator, and a NiMH battery pack. The VUE's hybrid functionality includes: engine stop-start, regenerative braking, intelligent charge control of the hybrid battery, electric power assist, and electrically motored creep. Methods of improving urban and highway fuel economy via optimal use of the hybrid motor and battery, engine and transmission hardware and controls modifications, and vehicle enhancements, are discussed.

Signal delivery is the means of translating a physical parameter from a sensor measurement to the application software in the electronic controller. Signal delivery is also translating a digital word from the application software to an actuator response. In both cases, there are many transform functions along the path that will introduce noise, error, and non-linearity. This paper will discuss the importance of understanding the error and sensitivity to variation that signal delivery analysis provides. The analysis will direct design change to improve control system robustness as well as decisions for failure events.

A new generation Northstar DOHC V8 engine has been developed for a new family of rear-wheel-drive (RWD) Cadillac vehicles. The new longitudinal engine architecture includes strategically selected technologies to enable a higher level of performance and refinement. These technologies include four-cam continuously variable valve timing, low restriction intake and exhaust manifolds and cylinder head ports, a steel crankshaft, electronic throttle control, and close-coupled catalysts. Additional design features beyond those required for RWD include optimized block ribbing, improved coolant flow, and a newly developed lubrication and ventilation system for high-speed operation and high lateral acceleration. This new design results in improved performance over the entire operating range, lower emissions, improved fuel economy, improved operating refinement, and reduced noise/vibration/harshness (NVH).

A number of different data networks have been implemented for electronic control unit communication in vehicles to date. Each network serves a particular need, such as low-cost networking of cab components or high-speed networking of powertrain components. Although each communication network performs its original purpose, the different communication networks, especially those using hardware-based messaging protocols, are expensive to integrate for information sharing and are not readily upgradeable with new messages. This is complicated by the growing number of different communication networks for vehicles, often driven by OEM and supplier technology consortiums rather than by end-user requirements. The result is added vehicle-support costs for the OEM, dealership and customer to maintain multiple networks.

In an effort to improve the reliability of electronic control modules used to automate operation of trucks, a database was conceived to aid in the proper selection of electronic components. An accompanying application program provided a means of information exchange between the user and the database, while controlling (accessing, updating, and navigating through) the database.

Three-way catalysts provide a means of catalytically achieving lower NOx emission levels while maintaining good control of HC and CO emissions. However, very accurate control of air-fuel ratio is necessary. The precise air-fuel ratio control required is accomplished by employing a closed loop fuel metering system in conjunction with an exhaust gas sensor and an electronic control unit. To gain production experience with this type of system, General Motors is introducing it on two 1978 engine families sold in California. One is a 2.5 litre L-4 engine and the other is a 3.8 litre V-6 engine. Closed loop controlled carburetors are used on both systems. This paper discusses these 1978 systems. The components used on both systems are described and emission and fuel economy results are reviewed.