Emerging Works on Wireless Inductive Power Transfer: AUV Charging from Constant Current Distribution and Analysis of Controls in EV Dynamic Charging

Wireless power transfer through inductive coupling, termed as inductive power transfer (IPT), is one of the important technologies in power electronics that enable transfer of power between entities without physical connections. While it has seen significant growth in the areas such as electric vehicle charging, phone charging and biomedical implants, its emerging applications include charging of autonomous underwater vehicles (AUVs) and dynamic charging of electric vehicles from the roadway. This dissertation addresses a few key challenges in these areas of IPT applications, paving the way for future developments. For the WPT for AUV, the recently developing sea-bed installed marine systems are targeted, which typically gets power from on-shore sources through constant dc low-current distribution. As the present underwater IPT topologies are not suitable for such applications, this dissertation proposes underwater IPT topologies to interface directly with such constant current distribution and provide a constant voltage output supply to the on-board systems inside the AUVs. The considerations for seawater losses and the small-signal models for control purposes are also addressed. Analysis and experimental results are provided for validations of the analytical designs and models. In the area of electric vehicle dynamic wireless power transfer (EV DWPT), the comparison of control performances of different coupler, compensation topologies and control implementations are addressed. The effect of communication latency on control bandwidth are also addressed. The outcomes are presented through analysis and simulations, and based on that future research recommendations are made to pave way for future commercial developments of well regulated and interoperable EV DWPT systems

Applications of Power Electronics

Power electronics technology is still an emerging technology, and it has found its way into many applications, from renewable energy generation (i.e., wind power and solar power) to electrical vehicles (EVs), biomedical devices, and small appliances, such as laptop chargers. In the near future, electrical energy will be provided and handled by power electronics and consumed through power electronics; this not only will intensify the role of power electronics technology in power conversion processes, but also implies that power systems are undergoing a paradigm shift, from centralized distribution to distributed generation. Today, more than 1000 GW of renewable energy generation sources (photovoltaic (PV) and wind) have been installed, all of which are handled by power electronics technology. The main aim of this book is to highlight and address recent breakthroughs in the range of emerging applications in power electronics and in harmonic and electromagnetic interference (EMI) issues at device and system levels as discussed in ?robust and reliable power electronics technologies, including fault prognosis and diagnosis technique stability of grid-connected converters and ?smart control of power electronics in devices, microgrids, and at system levels

Bidirectional Electric Vehicles Service Integration in Smart Power Grid with Renewable Energy Resources

As electric vehicles (EVs) become more popular, the utility companies are forced to increase power generations in the grid. However, these EVs are capable of providing power to the grid to deliver different grid ancillary services in a concept known as vehicle-to-grid (V2G) and grid-to-vehicle (G2V), in which the EV can serve as a load or source at the same time. These services can provide more benefits when they are integrated with Photovoltaic (PV) generation. The proper modeling, design and control for the power conversion systems that provide the optimum integration among the EVs, PV generations and grid are investigated in this thesis. The coupling between the PV generation and integration bus is accomplished through a unidirectional converter. Precise dynamic and small-signal models for the grid-connected PV power system are developed and utilized to predict the system’s performance during the different operating conditions. An advanced intelligent maximum power point tracker based on fuzzy logic control is developed and designed using a mix between the analytical model and genetic algorithm optimization. The EV is connected to the integration bus through a bidirectional inductive wireless power transfer system (BIWPTS), which allows the EV to be charged and discharged wirelessly during the long-term parking, transient stops and movement. Accurate analytical and physics-based models for the BIWPTS are developed and utilized to forecast its performance, and novel practical limitations for the active and reactive power-flow during G2V and V2G operations are stated. A comparative and assessment analysis for the different compensation topologies in the symmetrical BIWPTS was performed based on analytical, simulation and experimental data. Also, a magnetic design optimization for the double-D power pad based on finite-element analysis is achieved. The nonlinearities in the BIWPTS due to the magnetic material and the high-frequency components are investigated rely on a physics-based co-simulation platform. Also, a novel two-layer predictive power-flow controller that manages the bidirectional power-flow between the EV and grid is developed, implemented and tested. In addition, the feasibility of deploying the quasi-dynamic wireless power transfer technology on the road to charge the EV during the transient stops at the traffic signals is proven

INTEGRATED INDUCTIVE AND CONDUCTIVE CHARGING SYSTEM FOR ELECTRIC VEHICLES

The global electric vehicle (EV) market acceleration is facilitated by supporting policies deployed by governments and cities to reap multiple benefits in the fields of transport decarbonization, air pollution reduction, energy efficiency, and security. Currently, conductive chargers are a customary method of storing electric energy into the storage elements present onboard of an EV which is inadequate in supporting complete autonomy. The thriving inclination towards the design of autonomous vehicles has shaped wireless charging as an attractive solution in favor of complete autonomy. As long as the wireless charging infrastructure, as well as interoperability standards, are not completely developed, wired and wireless chargers have to co-exist onboard the vehicles for user convenience. Incorporation of an entire parallel wireless charging system on-board an EV, either during manufacturing or after-market increases size, weight, or cost while declining the electric range of the vehicle. The current requisite for multiple on-board charging options motivate the necessity for a solution for efficiently integrating wired and wireless charging systems. In this Ph.D. research, we propose multiple charging architectures capable of integrating inductive and conductive charging systems. The proposed architectures merge the output rectifying stage of an inductive charging system to the existing on-board charger eliminating the additional weight and volume associated with a wireless charger. Since the proposed system involves multiple power conversion stages, a system level study is carried out to select feasible topologies capable of maximizing the efficiency of an integrated system. Additionally, an extended harmonic approximation (EHA) technique is introduced to increase the accuracy of a resonant converter model facilitating the optimized design parameter selection of an inductive charging system. Furthermore, a novel analog synchronous rectification circuit is proposed and designed to enable active rectification maximizing power transfer efficiency. For proof of concept verification, a laboratory prototype of a 3.3kW Silicon Carbide (SiC) based integrated wireless charger is developed that can be interfaced to a variable input voltage (85-265 Vrms) 50/60Hz AC grid. According to the experimental measurements, the charger draws an input current with a total harmonic distortion of 1.3% while achieving an overall efficiency of 92.77% at rated output power

A Wireless Charging System Applying Phase-Shift and Amplitude Control to Maximize Efficiency and Extractable Power

Wireless power transfer (WPT) is an emerging technology with an increasing number of potential applications to transfer power from a transmitter to a mobile receiver over a relatively large air gap. However, its widespread application is hampered due to the relatively low efficiency of current Wireless power transfer (WPT) systems. This study presents a concept to maximize the efficiency as well as to increase the amount of extractable power of a WPT system operating in nonresonant operation. The proposed method is based on actively modifying the equivalent secondary-side load impedance by controlling the phase-shift of the active rectifier and its output voltage level. The presented hardware prototype represents a complete wireless charging system, including a dc-dc converter which is used to charge a battery at the output of the system. Experimental results are shown for the proposed concept in comparison to a conventional synchronous rectification approach. The presented optimization method clearly outperforms state-of-the-art solutions in terms of efficiency and extractable power

LYAPUNOV FUNCTION-BASED STABILIZING CONTROL SCHEME FOR WIRELESS POWER TRANSFER SYSTEMS WITH LCC COMPENSATION NETWORK

A stabilizing control scheme based on a Lyapunov function is proposed for wireless power transfer (or WPT) systems. A state-space model of the WPT system is developed and the Lyapunov function is formulated based on an energy equation of the system involving state variables. The internal resistance of a battery varies during charge and discharge. Therefore, if a WPT system is used to charge a battery, its output load will vary. Furthermore, the coupling coefficient between the transmitter (primary) and receiver (secondary) coils decreases when they are misaligned. Comparative case studies are conducted to verify the efficacy of the proposed controller in maintaining stability of the WPT system under load variation and acute misalignment of transmitter and receiver coils

Power Converters in Power Electronics

In recent years, power converters have played an important role in power electronics technology for different applications, such as renewable energy systems, electric vehicles, pulsed power generation, and biomedical sciences. Power converters, in the realm of power electronics, are becoming essential for generating electrical power energy in various ways. This Special Issue focuses on the development of novel power converter topologies in power electronics. The topics of interest include, but are not limited to: Z-source converters; multilevel power converter topologies; switched-capacitor-based power converters; power converters for battery management systems; power converters in wireless power transfer techniques; the reliability of power conversion systems; and modulation techniques for advanced power converters

Edge Devices for Internet of Medical Things: Technologies, Techniques, and Implementation

The health sector is currently experiencing a significant paradigm shift. The growing number of elderly people in several countries along with the need to reduce the healthcare cost result in a big need for intelligent devices that can monitor and diagnose the well-being of individuals in their daily life and provide necessary alarms. In this context, wearable computing technologies are gaining importance as edge devices for the Internet of Medical Things. Their enabling technologies are mainly related to biological sensors, computation in low-power processors, and communication technologies. Recently, energy harvesting techniques and circuits have been proposed to extend the operating time of wearable devices and to improve usability aspects. This survey paper aims at providing an overview of technologies, techniques, and algorithms for wearable devices in the context of the Internet of Medical Things. It also surveys the various transformation techniques used to implement those algorithms using fog computing and IoT devices