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This paper presents an energy-optimal deceleration planning system (EDPS) to maximize regenerative energy for electrified vehicles on deceleration events perceived by map and navigation information, machine vision and connected communication. The optimization range for EDPS is restricted within an upcoming deceleration event rather than the entire routes while in real time considering preceding vehicles. A practical force balance relationship based on an electrified powertrain is explicitly utilized for building a cost function of the associated optimal control problem. The optimal inputs are parameterized on each computation node from a set of available deceleration profiles resulting from a deceleration time model which are configured by real-world test drivings.

This paper suggests a method to formulate the driveline torque command for vehicles that use electric motor as part of their sources for providing driving power. The shape of the driveline torque profile notably influences the drivability criteria of the vehicle, and among them, driveline NVH and responsiveness are often tradeoffs for each other. Hence the real-time computed driveline torque profiling (DTP) enables formulation of the effective torque command at any given time to simultaneously satisfy both NVH and responsiveness criteria. Such task is fulfilled by using a shaft distortion prediction model based on a motor speed observer. A compensation torque command based on the amount of shaft distortion is formulated to prevent the shaft distortion with minimum effort. The effectiveness of the suggested driveline torque profiling method is verified using an actual vehicle, and the vehicle NVH and responsiveness are numerically assessed for comparison.

This paper examines the effect of pulse-and-glide (PnG) driving strategies on the fuel efficiency when applied on parallel HEVs. Several PnG strategies are proposed, and these include the electrical, mechanical, and combined PnG strategies. The electrical PnG strategy denotes the hybrid powertrain control tactics in which the battery is charged or discharged according to the power demanded while maintaining the constant vehicle speed. On the other hand, the mechanical PnG strategy denotes the powertrain control tactics in which the vehicle accelerates or decelerates according to the power load while minimizing the battery usage. The combined PnG strategy involves both electrical and mechanical strategies to find a balanced point in between them. Here, a tradeoff relationship between the fuel efficiency and the vehicle drivability related to the tracking performance of the desired target speed is revealed.

To make the smart hybrid solution, Hyundai introduces the first full hybrid system to use conventional 6-speed step ratio automatic transmission and lithium polymer battery. The simple and economical Sonata hybrid structure offers fun-to-drive characteristics with cooperative control of the engine and motor. The capacity of the electric power system for the Sonata hybrid system is relatively small compared to other existing hybrid systems, but provides smooth and delicate drivability in any extreme environmental situation. The engine clutch which is placed between engine and motor is the core component of the Sonata hybrid system. The precise control of the engine clutch enables optimal power distribution for the two power sources. Anti-jerk strategy is more important to the Sonata hybrid system because there is no active damping component such as a torque converter found in conventional automatic transmission.

The main objective of the combined control unit is to develop a cost effective and optimal control system that manage the proper torque distribution and minimize the loss of communication delay caused by individual inter-controller cooperative control. The control systems of the Hybrid Electric Vehicle (HEV) are more complicated than conventional vehicle. The major difference of HEV has Power Electronics (PE) system. The control systems of PE-part in the HEV are consisted with Hybrid Control Unit (HCU), Motor Control Unit (MCU) and Battery Management System (BMS) individually. In this study, the controllers of PE system are combined into one PCB (1Board-1Micom). Vehicle-testing and dynamometer-testing results confirm that the combined control unit achieves approximately 45% cost and 47% weight reduction compare to the non-combined (Individual controllers) same hybrid vehicle.