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A plug-in hybrid electric powertrain, as one of the most promising solutions to increase the fuel economy and to meet the stringent requirements of low emissions urban zones, has been investigated and developed for a light duty commercial vehicle application in this work. The plug-in hybrid electric powertrain combines an advanced small diesel internal combustion engine with a high energy battery pack, capable to assure an extended range in pure electric mode for specific areas, like the low/zero emissions urban zones. Since the right size of the powertrain components is essential to fully exploit the benefits of the hybridization, an advanced methodology has been proposed to optimize the design of the plug-in hybrid powertrain at an early phase. This methodology is based on the genetic algorithm approach for the choice of the powertrain component characteristics, combined with a quasi-optimal energy management strategy that is the Equivalent fuel Consumption Management Strategy (ECMS). The performance of the hybrid electric powertrain which was designed through the proposed methodology were then assessed and analyzed over the Worldwide Harmonized Light Duty Driving Cycle (WLTC) by means of a simulation model, thus demonstrating its effectiveness in addressing the issue of the powertrain components sizing from the early stage of the design process.

In the context of the evolution of in-vehicle electronic and electrical architecture as well as the rapid development of quantum computers, post-quantum algorithms, such as NTRUEncrypt, are of great significance for in-vehicle secure communications. In this paper, we propose and evaluate, for the first time, a NTRUEncrypt enhanced session key negotiation for the in-vehicle Ethernet context. Specifically, the time consumption and memory occupation of the NTRUEncrypt Elliptic Curve Diffie–Hellman (ECDH), and Rivest–Shamir–Adleman (RSA) algorithms, which are used for session key negotiation, are measured and compared. The result shows that, besides the NTRUEncrypt’s particular attribute of resisting quantum computer attacks, the execution speed of session key negotiation using NTRUEncrypt is 66.06 times faster than ECDH, and 1530.98 times faster than RSA at the 128-bit security level. The memory occupation of the algorithms is at the same order of magnitude. As the transport layer security (TLS) protocol can fulfill most performance requirements of the automotive industry, post-quantum enhanced session key negotiation will probably be widely used for in-vehicle Ethernet communication.

As the demand for green energy with high efficiency and low carbon dioxide (CO2) emissions has increased, solid oxide fuel cells (SOFCs) have been intensively developed in recent years. Integrated gasification fuel cells (IGFCs) in particular show potential for large-scale power generation to further increase system efficiency. Thus, for commercial application of IGFCs, it is important to design reliable multi-stacks for large systems that show long-term stability and practical fuel gas for application to industrial equipment. In this work, a test rig (of a 5 kW SOFC system, with syngas from industrial gasifiers as fuel) was fabricated and subjected to long-term tests under high fuel utilization to investigate its performance. The maximum steady output power of the system was 5700 W using hydrogen and 5660 W using syngas and the maximum steady electrical efficiency was 61.24% while the fuel utilization efficiency was 89.25%. The test lasted for more than 500 h as the fuel utilization efficiency was larger than 83%. The performances of each stack tower were almost identical at both the initial stage and after long-term operation. After 500 h operation, the performances of the stack towers decreased only slightly under lower current and showed almost no change under high current. These results demonstrate the reliability of the multi-stack design and the prospect of this SOFC power-generation system for further enlarging its application in a MWth demonstration.