There are many important trade-offs and constraints on cost, volume, weight, conduction losses, switching losses, microcontrollers, isolation, voltage and current levels, voltage and current ripples, battery specifications, charging–discharging algorithms, control system, switch gate drivers, and efficiency of battery chargers in electric vehicles. In this paper, a well-known power electronic topology commonly used in recent relevant studies is considered, and some important technical considerations with regard to the mentioned trade-offs and constraints are discussed in detail for the first time. The discussion concerns the practical and theoretical experiences in implementation of battery chargers and charging stations of electric vehicles exclusively, and it can be extended to various other power electronic topologies.

This paper proposes a battery charger for electric vehicles based on pulse-current charging method which has great distinct advantages and substantially enhances charging process. It applies positive, negative, and zero currents for each cycle. On the one hand, drastic changes in the battery current and power during the cycles appear in the output of the battery charger, negatively affect the terminal, and frequently change the output active power. This condition is also important in battery chargers which have not DC-AC stage and are powered by other power sources, for instance, fuel cell. On the other hand, the output active and reactive powers must track constant values without any variations for participation in vehicle-to-grid technology. Thus, a particular parallel battery-capacitor topology is suggested in practice and then an innovative control system is precisely designed in order to implement pulse-current method and transfer smooth power in the presence of the intrinsic drastic changes in the battery power. The proposed system is compared with the recent pulse-current battery chargers. The results demonstrate the effectiveness of the solution.

This paper proposes a control framework for a cooperative robotic system to grasp and handle an object with known geometry in the presence of uncertainty in robot dynamics. Based on passive decomposition approach, dynamic equations of the cooperative robotic system are decomposed into two decoupled systems, shape and locked systems. The locked system and the shape system are controlled by two fuzzy sliding mode controllers (SMCs). Stability is studied through passivity property and Lyapunov theorem. Simulation results confirm that the proposed control scheme works well.

Summary: This paper proposes a novel control framework for a single-master/multi-slave teleoperation system to grasp and handle an object, considering nonlinearity and uncertainty in the dynamics of the slaves and time-varying delay in the communication channel. Based on passive decomposition approach, the dynamics of the slaves are decomposed into two decoupled systems, and then two higher order sliding mode controllers are designed to control them. Also, a synchronization control methodology for the master is developed. Stability is fully studied using the passivity property and Lyapunov theorem. Finally, simulation and practical results confirm that the control system works well against the conditions.