Abla O. Hariri

A Computational Approach for a Wireless Power Transfer Link Design Optimization Considering Electromagnetic Compatibility

This paper presents an electromagnetic-artificial intelligence design optimization approach of a wireless power transfer link (WPTL). Electromagnetic solutions from a 3-DFE model of the WPTL were utilized to minimize the field signature around each design while maintaining high efficiency. The reduced field signatures around the WPTL would enable the achievement of designs that are in accordance with international electromagnetic compatibility (EMC) standards such as international commission on nonionizing radiation protection guidelines with respect to public exposure levels of EM signatures below 27 μT. As the optimization process involved utilizing a large number of fitness function evaluations, numerous 3-DFE solutions were required increasing the computational burden. Artificial neural networks were developed, trained, and used to produce the required equivalent 3-DFE solutions to evaluate the fitness function. As a result, this process significantly reduced the computational time by nearly 90%. The genetic algorithm-based optimization process yielded the desired results of electromagnetically compatible WPTL designs at the early development stage satisfying EMC standards.

An Integrated Characterization Model and Multiobjective Optimization for the Design of an EV Charger’s Circular Wireless Power Transfer Pads

A good magnetic design of a wireless electric vehicle (EV) charging system requires accurate characterization of the equivalent circuit parameters. This is while considering the effect of the magnetic core and the conductive shielding layers. In the literature, such an analysis is done using 3-D finite element analysis, which makes the design and optimization process time-consuming and computationally expensive. In this paper, an integrated analytical model for the characterization of a circular wireless power transfer EV pads is utilized. This analytical model provides a valuable tool to optimize the design process. This model is utilized when evaluating the objective function for each individual in the multiobjective Pareto Optimality optimization algorithm. The objective is optimizing the pads with three decision variables and four constraints.

EM-Taguchi Module for Characterization of WAD

Accurate performance characterization is critical in a design optimization environment. The electromagnetic (EM) design optimization of an ocean wave linear generator buoy or wave activated device (WAD) requires the use of large number of finite element-state space, design evaluations due to the stochastic behavior of the wave and the nonlinear nature of the device. This paper proposes the utilization of Taguchi orthogonal arrays method to reduce the EM, computational time needed to accurately characterize a WAD performance corresponding to a sea wave profile and for use in a design optimization environment.

Optimal sizing of inverters and energy storage for power oscillation limiting in grid connected large scale Electric Vehicle park with renewable energy

Power oscillations can result from the expansion of large-scale grid-connected Electric Vehicles (EV) parks fed from photovoltaic (PV) arrays which raising concerns about grid stability. This paper addresses the optimal sizing for the energy storage battery, its corresponding DC-DC power converter and the grid tie inverter to satisfy grid requirements and maximize the profit of a EV park owner under the utility constraints. This was achieved through two stages: probabilistic forecasting of the EV load pattern and optimal sizing of the battery and power converters by the aid of linear programming (LP). Three types of batteries were studied to support the EV park: Sodium Sulfur (NaS), Lead Acid (LA) and Vanadium-Redox (VR). Moreover, a sensitivity analysis was done by investigating the effect of changing the number of grid tie inverters. Results showed the effectiveness of the proposed solution in limiting the power oscillations at the point of common coupling with the grid and maximizing the EV parks owner profit. Results also revealed the superiority of the VR battery for a low number of grid tie inverters while LA was preferable for implementing higher numbers of grid tie inverters on the host grid while limiting the power fluctuations at the grid side.

An Iterative Design Approach for Shielding of WPT Systems in Electric Vehicle Charging Applications

Several factors are considered when designing a Wireless Power Transfer (WPT) system for Electric Vehicle (EV) charging. These include the efficiency of the system, amount of power transferred, near field emissions, cost, and weight. Reaching the best combination of design parameters often requires trade-offs between them. Accordingly, and starting from a given coil design, this paper proposes an iterative shield design approach for selecting an adequate aluminum shield radius and thickness, using Finite Elements (FE) Analysis, which ensures a safe level of EMC near field exposure, minimal cost, and minimal weight. Design considerations were done considering the 85 KHz frequency level set by SAE-J2954 TF.

Deployment of electric vehicles in an adaptive protection technique for riding through cyber attack threats in microgrids

The fault current level is different in grid connected and islanded microgrid fault cases for the same relay due to large integration of distributed energy resources in the latter. Therefore, protection systems must be adaptive and assisted with extensive communication networks to respond to the dynamic changes in the microgrid configurations. However, the microgrid must be protected even under the conditions of a cyber-attack which will render the communication link insecure or down. This paper proposes an adaptive protection scheme abiding by IEC 61850 communication standard for microgrids making them capable of riding-through communication failures by the aid of Electric Vehicle Parks. The control of the Electric Vehicle Park can identify a fault in the AC side based on direct measurements of frequency and voltage without the need for a communication signal. The most critical case is when the microgrid is islanded and the communication is down. In this case, the control will adjust the operation of the connected Electric Vehicles to inject a high current into the microgrid as demanded by the fault, allowing the relays to operate properly. The effectiveness of the proposed protection scheme is evaluated through detailed simulation. The results demonstrate the successful operation of the protective devices during the various modes of operation.

An integrated characterization model for the magnetic design of an EV charger's circular wireless power transfer pads

A good magnetic design of wireless Electric Vehicle (EV) charging system requires accurate characterization of the equivalent circuit parameters. This is while taking into consideration the proximity effect of the magnetic core and the conductive shielding layers. In the literature, such analysis is done using 3D finite element analysis (3DFE), which makes the design process time consuming and computationally expensive. In this paper, an integrated analytical model for the characterization of a circular Wireless Power Transfer (WPT) EV pads is utilized. The results compare well with the results from an FE model as well as experimental test. This analytical model provides a valuable tool to optimize the design process and introduce an element of numerical verification.