The Electric transit buses (ETBs) are the main source for public transit to get the cleaner environment. The ETBs have gained popularity around the globe since the last decade. The ETBs are 14 % of the total transit buses around the world. The ETBs are heavy EVs and need more power to charge the high capacity batteries. The batteries used in these buses have the energy capacities between 80 kWh to 550 kWh. Such high capacity batteries take more to get charged. In order to increase the adoption of ETBs, a suitable number of high power dc charging infrastructures need to be installed in various main cities of the nations. The ETBs can operate with battery alone or fuel cell or combination of these two. Such ETBs are named as battery electric transit bus (BETB), fuel cell electric transit bus (FCETB) and hybrid electric transit bus (HETBs). As of 2020, out of total ETBs around the globe, 70 % are HETBs, 20 % are FCETBs and 10 % are BETBs. In this paper, the key parameters and comparison among these three batteries are shown. The major EV market holders are China, US, Europe and japan. The charging protocol used in the US and Europe is combined charging system. The charger capacity has reached up to 500 kW as of 2020. With such high power chargers it takes only less than half an hour to charge the high power batteries.

This paper presents a review of non-isolated DC-DC converters of voltage enhancers. Relevant review details are presented about the topologies of converters, including boost, hybrid boost, three-level boost, multi-level boost, and three-level hybrid converters that are most commonly used in photovoltaic systems. In the end, there are also several voltage level enhancers that can replace the converters provided in photovoltaic systems. Finally, a comparison is made between the converters in terms of the number of elements used in the circuit and the complexity of controlling the switches in the converters with their advantages and disadvantages being presented in a table. Since the use of multi-level boost converters reduces the switch voltage stress, weight, and cost compared to the conventional mode and as they are also better at higher powers, they have been used significantly in different systems.

This paper describes the development of a new generation of single phase rectifier which is used to power telecommunications equipment. A rectifier is designed in such a manner to meets with all the requirements of the telecommunications industry. A number of common single phase topologies exist that could be realized as telecommunication power supplies, however, they do not completely satisfy all the industry requirements. This paper reviews recent progress in topology, control and design aspects in single phase PFC techniques. Different switching rectifier topologies are presented for various applications. Merits and limitations of these techniques are discussed. A detailed report of an investigation in the power converter system performance is also provided.

In recent years, the popularity of wireless inductive power transfer (WIPT) system for electric vehicle battery charging (EVBC) is always ever-increasing. In the WIPT inductively coupled coil structure is the heart of the system and the mutual inductance (MI) between the coupled coils is the key factor for effective power transfer. This paper presents the analysis of mutual inductance between the spiral square coils based on the crosssectional area ratio of spiral circular and spiral square coupled coils. The analytical computed MI values are compared with FEM (ANSYS Maxwell) simulation and Experimental computed values. Finally, the designed spiral square coils are implemented in a laboratory prototype model and at the receiver side for effective electric vehicle (EV) battery charging a closed-loop PID controller is implemented for DC-DC buck converter. The effectiveness of the proposed controller has been tested by providing sudden changes in mutual coupling and change in reference value. The proposed system is suitable for both stationary and dynamic wireless EVBC.

Due to increasing air pollution and fuel supply problems, the use of electric vehicles has been considered as a clean alternative to traditional cars. Extensive studies have been conducted on the environmental effects of these cars and their benefits in reducing air pollution have been proven. However, the high penetration of electric vehicles can create new challenges in the power system, especially concerning their charging demands. The change in demand due to electric vehicles creates challenges and concerns for the electric system. The electrical system must be ready to respond to a new load called “the demand for electric vehicles”. In this paper, by providing the optimal charging price and considering traffic restrictions, remained charging limits and charging rates, it is possible to choose the right charging station. This action reduces the possibility of damage to the network and leads to the improvement of network technical parameters, including losses and voltage profile. The results shows the effectiveness of the model.

Finding effective solutions to enhance the process of electric vehicle charging has been the main subject of numerous studies. This paper presents a novel bidirectional multiport rectifier that can be used as a wall-box converter that is installed in the parking lot of smart buildings and is capable of providing DC-link for local DC loads, such as DC home appliances and charge connected EV, simultaneously. The proposed converter is capable of working in G2H/G2VH/V2H/V2G modes, enabling the utility grid and costumers to use the EV as a mobile power source and reactive power compensator. A control method is also presented that enables the converter to control active and reactive power according to the smart grid or customer processed commands. To validate the features of the proposed converter, it is simulated in MATLAB/SIMULINK and the results are analyzed. A reduced-scale experimental setup of the proposed converter is built and tested, and the experimental results confirm the simulation ones.

Nowadays, electric vehicles have gained more attention due to environmental issues. In this regard, charging the batteries of electric vehicles is one of the main challenges. Because of recent advancements in power electronics, inductive power transfer (IPT) chargers are rapidly developing due to some advantages compared to conventional plug-in chargers, such as no cable required and higher reliability. This new solution allows the building of low-cost and intelligent energy transfer systems. IPT chargers have a transmitter coil on the ground and a receiver coil on the vehicle. Due to the air gap, the magnetic coupling between the primary and secondary is weak. In this paper, the structure of a typical bidirectional charger based on a resonant converter is developed by a weak magnetic coupling. Finally, the obtained model and the performed computational analyzes are confirmed by simulation on a 6.6 kW battery charging converter in the Simulink Matlab. It is shown that by changing the electromagnetic coupling in the range of 0.1 to 0.9, if the resonance frequency is kept constant with a variable resonance capacitor, the battery charging voltage remains almost constant in the range of 440 V to 450 V.

Background and Objectives: {R1-1} Increasing environmental problems have led to the spread of Electric Vehicles (EVs). One of the attractive research fields of electric vehicles is the charging battery of this strategic product. Electric vehicle battery chargers often lack bidirectional power flow and the flexibility to handle a wide range of battery voltages. This study proposes a non-isolated bidirectional DC-DC converter connected to a T-type converter with a reduced number of switches to solve this limitation.Methods: The proposed converter uses a DC-DC converter that has an interleaved structure along with a three-level T-type converter with a reduced number of switches and a common ground for the input and output terminals. Space vector pulse width modulation (SVPWM) and carrier based sinusoidal pulse width modulation (CBPWM) control the converter for Vehicle to grid (V2G) and grid to Vehicle (G2V) operation, respectively.Results: Theoretical analysis shows 96.9% efficiency for 15.8kW output power and 3.06% THD during charging with low battery voltage ripple. In V2G mode, it achieves an efficiency of 96.5% while injecting 0.5 kW of power into the 380 V 50 Hz grid. The DC link voltage is stabilized. The proposed converter also provides good performance for a wide range of battery development.Conclusion: The proposed converter offers high efficiency and cost reduction. It provides the possibility of charging a wide range of batteries and provides V2G and G2V power flow performance. The proposed converter is capable of being placed in the fast battery charging category. The ability to charge two batteries makes it a suitable option for charging stations.