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Inductive power transfer (IPT) technology has been approved to be convenient and reliable interface for charging and discharging the electric vehicles (EVs). Precise model for such system can help designers and researchers to anticipate, optimize, and evaluate its behavior amid the development. Thus, this paper presents a physics-based co-simulation platform for the bidirectional IPT system (BIPTS) in EVs’ applications. The platform is established through the coupling between finite element and circuit analysis. The power electronic converters and controllers are developed in Simulink; and the power pads are modeled in Magnet environment. The two parts are lined together through the compatible Simulink plug-in tool. In addition, a state-space dynamic mathematical model for the same BIPTS is derived and implemented in MATLAB environment. A 1.2 kW BIPTS is analyzed under different dynamics by both models and the results are compared. The effect of the nonlinearities and the magnetic material characteristics on the BIPTS's performance is assessed, in terms of errors and harmonics analysis. The analysis considered both the full and light loading operating conditions in the system. Finally, a small-scale prototype for a BIPTS is built, tested, and compared with the co-simulation results for verification purposes. The proposed co-simulation could provide accurate prediction for the system's dynamics, during both charging and discharging operation. The scheme is generic and can be easily expanded to different pad structures, compensation networks, and converter topologies. [ABSTRACT FROM PUBLISHER]

Electric vehicle (EV) can act as an energy consuming device or a distributed energy resource in the concepts known as vehicle-to-grid (V2G) and grid-to-vehicle (G2V). The bidirectional wireless power interface is a successful choice for this application, since it provides automatic, reliable, and safe operation. Therefore, this paper presents modeling and assessment analysis for the steady-state performance of bidirectional inductive wireless power transfer system (BIWPTS) in EV implementations. The analysis is presented for the three main compensation configurations: LC-series, LC-parallel, and LCL-topology. Moreover, the steady-state equivalent circuit-based mathematical models for all topologies are developed. These models were used to precisely determine the system response during V2G and G2V operations based on Fourier series. The study presents evident criteria to pick among the different BIWPTS structures in the diverse applications. The proposed analyses were verified both in simulation and experiment. The results demonstrate the ability of the proposed models to provide accurate estimation for BIWPTS performance under various operating and control conditions. Also, the evaluation analysis shows that LCL-topology is more appropriate for the bidirectional operation due to the simple design and control requirements, and being less sensitive to the misalignment. [ABSTRACT FROM AUTHOR]

A flexible, automatic, reliable, and safe charging and discharging system for electric vehicles (EVs) and hybrid EVs is crucial in vehicle-to-grid (V2G) operation. The bidirectional inductive wireless power transfer system (BIWPTS) is an ideal solution in this situation. With authentic power-flow models for the BIWPTS in hand, designers and operators can predict, optimize, and analyze the interaction performance between the EV and the grid. Thus, this paper presents a harmonics-based theoretical power-flow model for BIWPTS for charging and discharging EVs in V2G applications. The proposed model provides accurate estimation for the active and reactive power flow during V2G and grid-to-vehicle modes. Moreover, the impact of the circuit losses and harmonics, due to the high-frequency power inverters, on the power-flow performance is investigated. This effect is stated mathematically by four novel power-flow criteria formulas. New conditions for achieving maximum active and reactive power, and unity and zero power-factor system operation, are also developed. The sensitivity of the circuit performance to the variation of its parameters has been studied. For validation purposes, a computer-based model and experimental platform of BIWPTS for EV applications are developed and tested. The comparison between the theoretical, simulation, and experimental results verified the proposed models and analysis. [ABSTRACT FROM PUBLISHER]

This paper presents a clear methodology for achieving the optimum design of LCL bidirectional inductive wireless power transfer system (BIWPTS) for electric vehicle applications. The proposed strategy depends on electromagnetic field computations joined with analytical models. A 3-D finite-element model for 8-kW polarized double-D power pad was modeled, optimized, and built. Moreover, the choice of the power factor correction and the impedance matching elements was investigated. Following the proposed design considerations, a BIWPTS model was developed in MATLAB Simulink and its outcomes were compared with the theoretical model results. In addition, a small scale prototype was assembled using the same design with reduced dc voltage levels. The models were tested during charging and discharging operation, and good correlation was seen between every one of them. [ABSTRACT FROM AUTHOR]

This paper presents an improved complex-vector dynamic model for a three-phase induction machine (IM) with stator interturn short-circuit fault. The paper proposes an accurate and meaningful approach to the faulty stator leakage inductance and describes a nonlinear phenomenon in the faulty circuit. The asymmetric model is developed in detail and represented in state-space (SS) form with the flux-linkages as the SS variable. Based on the proposed model, steady-state complex-vector, operational, and sequence component equivalent circuits are derived for fault detection and identification purposes. For reasons of verification, the model is simulated in MatLab environment and experimentally corroborated for a 1HP three-phase squirrel-cage IM. The simulations and experiments are compared at no-load and loading condition for both transient and steady-state response. The permanent regime analysis studies the model with respect to the fault severity factor, fault resistance, and load variation. The proposed model shows high correlation with the experimental results. [ABSTRACT FROM PUBLISHER]

This paper presents a cost effective control algorithm for standalone batteryless photovoltaic (PV) systems. The control is driven by a fuzzy-based maximum power point tracker which has the capabilities to maintain high-energy conversion efficiency under different weather and load conditions. General design considerations are presented based on the linearization of the dynamic model of the entire system which consists of PV panel, Cuk converter, and motor load. For our particular fuzzy-MPPT controller, these design considerations are combined with an artificial intelligent technique to achieve the optimum control design. Furthermore, the developed control algorithm has voltage regulation capability to protect the load from overvoltage during light load conditions and a fast digital overload protection. The transient and steady-state performance of the entire system was modeled by a nonlinear state-space representation. The proposed control is simulated in MATLAB and experimentally tested under the fast variation of climatic conditions for verification purposes A very good agreement has been shown between theoretical, simulations, and experimental results [ABSTRACT FROM PUBLISHER]