A novel method for evaluating compensation networks in IPT systems is proposed for a fair comparison. An optimal control strategy is adopted in the comparison to ensure operation under optimal conditions. Results indicate efficiency boundary can be used as a powerful tool for intuitive evaluation of the compensation networks.

Dynamic inductive power transfer (IPT) can be used to charge moving electric vehicles (EVs) through the magnetic coupling between primary coils in a road with secondary coils onboard an EV. However, consistency in charging requires stability of power transfer, which is significantly affected by variations in the alignment between conventional primary and secondary coils in relative motion. This paper proposes a new coil structure for dynamic IPT systems with a high degree of tolerance to coil misalignment. The reluctance model is presented for the proposed coil to further investigate the influence of coil widths on the mutual inductance (M). Results indicate that a trade-off exists between improving M and tolerance to coil misalignment.

This paper presents a new IPT compensation topology that can be operated at two different frequencies to form either primary series and secondary parallel (S-P) or primary parallel and secondary parallel (P-P) compensation. Model are presented to demonstrate how this transformation between S-P and P-P compensations with dual frequency control. The simulated results of a 1 kW IPT system have verified that the proposed system can remain output power with phase-shift modulation (PSM) and allows for efficient power transfer despite large pad misalignments by operating at different compensation.

Wireless electric vehicle (EV) charging is based on the Inductive Power Transfer (IPT) technology. The use of Wide Bandgap (WBG) devices like Silicon Carbide (SiC) and Gallium Nitride (GaN) as well as adopting Zero Voltage Switching (ZVS) and Zero Current Switching (ZCS) have significantly improved the performance of the primary side of typical IPT systems. However, in high power EV charging applications, the secondary side incurs high conduction losses when a diode rectifier is employed. To improve overall efficiency and power transfer capability, this paper proposes a novel and self-driven Synchronous Rectifier (SR) using Rogowski coil fabricated by printed circuit board (PCB) technology, which lowers the secondary side conduction losses. Theory and simulated results are presented to show the suitability of the proposed method, which uses a simple circuit configuration and does not require any information from the primary.

This paper proposes a low-cost inductive power transfer (IPT) system, comprising an uncompensated foil primary coil and a compensated vertical Litz-wire secondary coil structure, for stationary electric vehicle (EV) charging applications. A mathematical model is presented for the proposed system, and a 2 kW case study shows comparable performance to a dual-compensated IPT system.

The shielding effect of rebar arrays on magnetic fields poses a challenge for inductive power transfer (IPT) systems that power sensors in structural health monitoring systems. In this paper, we propose a method to enhance the maximum output power of IPT systems by reducing the shielding effect of the rebar array. The shielding effect is caused by the magnetic field produced by the induced current in the rebar array. To overcome this, an additional coil is mounted on the rebar to couple with two adjacent rebar loops. By adjusting the capacitance value in series with the additional coil, the equivalent impedance of the rebar loop is changed, altering the phase of the induced current and allowing it to effectively superimpose with the magnetic field produced by the transmitter coil. The equivalent circuit of the system is analyzed based on the dipole coil as the transmitter and receiver coil. Furthermore, a parameter design method of capacitance in series with the additional coil is presented to enable the system to achieve maximum output power capacity. Circuit simulation results verify that this method can increase the maximum output power from 4.3W to 13.5W.

The widespread integration of Distributed Generation (DG) and new loads such as Electric Vehicles (EVs) into power distribution networks presents substantial technical challenges for network operators, such as voltage fluctuations and phase unbalance. These can be addressed by many power electronic devices with advanced control strategies, including the Hybrid Transformer (HT). This paper presents a new three-phase HT concept which can perform multiple functions, including voltage regulation and voltage balancing, to address power quality problems in distribution networks. Theory and control strategy are presented, along with simulated results incorporating an unbalance-tolerant control scheme and 3D Space Vector Modulation, to demonstrate the validity of the proposed HT topology. Its advantages include being retrofittable to existing distribution transformers, not requiring bulky low-frequency converter magnetics, having a low semiconductor component count, and allowing reduced DC-link capacitances. This makes it cost-effective, compact and light weight in comparison to the existing topologies that provide similar functionality.

To mitigate the electric vehicle (EV) overstaying problem in fast charging pools and increase the utilization of EV chargers, a dynamic penalty mechanism based on an optimization model is proposed in this paper. The simulation results show that the proposed mechanism can effectively reduce the number of overstaying EVs, while increasing the EV entry rate, utilization rate, and revenue of chargers.

This paper presents a novel idea to enhance the switching of power electronic converters used for driving closely spaced multi-transmitter (MT) wireless power transfer (WPT) systems. Cross coupling amongst the transmitters is an undesirable phenomenon for power electronic converters as they induce an spurious voltage in the adjacent coils. Therefore, with the use of coupled inductors (CPIs) a new method to mitigate the effects of cross couplings is proposed. To study the effect of CPIs on soft switching, an MTWPT system consisting of three transmitters and one receiver is used as a case study. The system is mathematically analysed, numerically simulated, and experimentally tested, and the results validate the efficacy of the proposed approach.

Inductive power transfer (IPT) systems are increasingly being used in numerous industrial applications, which essentially require power without any physical contacts. In contrast to unidirectional IPT systems, bidirectional IPT systems are inherently higher-order resonant networks and relatively complex in modeling, design, and control. The complexity further exacerbates with the increase in number of pickups or loads, making design and implementation of such systems a real challenge. This paper, therefore, develops a multivariable dynamic model for a multipickup bidirectional IPT system, which can provide an accurate insight into the behavior of this system and can be used for controller synthesis under variations of component values. The output sensitivity to various parameters and the interaction among various control variables and degree of controllability of the system are investigated using frequency domain analysis. The validity of the model is verified under various operating conditions by comparing the predicted behavior with a 1-kW prototype of a bidirectional IPT system with two pickups. Measured results convincingly demonstrate that the proposed model accurately predicts the dynamic behavior of bidirectional IPT systems with multiple pickups and can, therefore, be used as a valuable tool for both dynamic analysis and controller design.

Bi-directional Inductive Power Transfer (BDIPT) technique is suitable for renewable energy based applications such as electric vehicles (EVs), for the implementation of vehicle-to-grid (V2G) systems. Recently, more efforts have been made by researchers to improve both efficiency and reliability of renewable energy systems to further enhance their economical sustainability. This paper presents a comparative reliability study between a typical BDIPT system and an individually controlled segmented BDIPT system. Steady state thermal simulation results are provided for different output power levels for a 1.5 kW BDIPT system in a MATLAB/Simulink environment. Reliability parameters such as failure rate and mean time between failures (MTBF) are compared between the two systems. A nonlinear programming (NP) model is developed for optimizing charging schedule for a stationery EV. A case study of EV optimum charging is provided for a 24 hours period indicating minimum cost and higher reliability.

A novel replaceable, modularized energy storage system with wireless interface is proposed for a battery operated electric vehicle (EV). The operation of the proposed system is explained and analyzed with an equivalent circuit and an averaged state-space model. A non-linear feedback linearization based controller is developed and implemented to regulate the DC link voltage by modulating the phase shift ratio. The working and control of the proposed system is verified through simulation and some preliminary results are presented.

The ever increasing demand for energy has led towards distributed renewable energy generation systems. Such systems depend on a well integrated information and communication infrastructure for interconnection and integration of various energy sources, loads, and environmental sensors to achieve intelligent distributed control and management. This paper describes the design and implementation of an intelligent hybrid communication system for a micro distributed energy generation application. The industrial standard controller area network (CAN) bus was selected to connect various energy sources and loads, due to its resistance to noisy conditions. An application specific communication protocol was designed, based on the CAN protocol, to allow data exchange and control. The proposed communication system was verified using a prototype micro wind generation system with multiple power converters and a central energy management unit. Combined with intelligent control algorithms, which could in future be incorporated in the energy management unit, the system has the ability to perform optimised load balancing and energy usage planning.

Traditionally, the power supplies employed in low voltage and very high current applications, such as electroplating, use line frequency transformers and thyristor-based control circuits. Such power supplies are bulky and inefficient, taking up valuable plant area and incurring significant operational costs. This study proposes an efficient and compact power supply suited to high current and low voltage applications. It uses a multi-level converter to convert line frequency input waveforms to a high frequency in a low cost and low loss manner. The output of the multi-level converter feeds an AC L-C-L resonant network to implement an easily controllable current source that, in turn, feeds a high current output stage. The output stage is modular, consisting of a number of easily constructed transformers and rectifier circuits that share voltage and current stresses. The proposed topology is modeled and simulated results are presented to verify its performance.

In this paper, common mode noise modeling of low-voltage high-current isolated full bridge boost dc-dc converters intended for fuel cell application is presented. Due to the tightly coupled primary and secondary windings of the transformer, such converter has inherently large capacitive coupling between input and output which is normally associated with high common mode noise generation. In this work, common mode noise sources in the converter are identified, and a common mode noise model is developed. Based on the established noise model, a practical CM filter is designed to comply with the CISPR-A requirements. Finally, a 3kW dc-dc converter including filters has been built and tested to verify the theoretical model. Experimental results confirm the theoretical analysis of the converter.

This paper presents an investigation into the performance of a low cost integrated micro-wind generation system. In comparison to a conventional micro-wind system, the integrated solution presented in the paper, which utilizes the phase inductances of the generator as the boost inductor, eliminates the requirement for a separate boost inductor and filter capacitor, significantly reducing the cost and the size. A commercially viable 1.2 kW integrated micro-wind system is designed and the details of the prototype implementation are presented. The performance of this prototype is compared with an equivalent conventional system and the experimental results are presented to demonstrate the viability of the integrated system as an efficient and cost effective solution.

Matrix converter (MC) based grid connected bi-directional inductive power transfer (BD-IPT) systems are preferable for numerous applications such as electric vehicle (EV) charging and vehicle-to-grid (V2G) systems due to their single-stage grid integration as opposed to two-stage grid integration of conventional BD-IPT systems. However MC based BD-IPT systems essentially produce harmonics which can have adverse effects on power quality of the utility grid. This paper presents a new control technique, through which the grid side harmonic distortion of MC based BD-IPT systems can be improved. A theoretical analysis is presented with simulations to show that the proposed approach is viable, and results suggest that the presented technique improves the power quality of the system significantly by minimizing the grid side harmonic distortion.

In medium-voltage (MV) drives, the switching frequency is limited to a few hundred Hz, for which high-performance control and modulation schemes are necessary to maintain acceptable current and torque distortion. Forced machine current control (FMCC) is a predictive control strategy for MV drives which was proposed in the early 1980s, which can be formulated for either torque or current control. Recently, model predictive direct torque control (MPDTC) and model predictive direct current control (MPDCC) have been developed, sharing with FMCC the use of hysteresis bounds, switching and prediction horizons. However, the relative performances of these schemes are yet to be compared. Through simulation, this paper compares the schemes across a range of operating points. It is shown that the steady-state performance of MPDxC and FMCC is similar when the switching horizon of MPDxC is limited. However, when the switching horizon is extended, the performance of MPDxC is shown to be superior to FMCC, the horizon of which is inherently restricted.

The control of a brushless dc (BLDC) motor, using bit-streams is presented. Bi-polar signals are represented using a uniformly weighted bit-stream which can be manipulated using simple digital logic to create a variety of control actions. This paper presents the functional elements required for the implementation of a proportional integral (PI) controller to affect speed and torque control on a BLDC motor. Preliminary experimental results on a standard BLDC motor using an Altera field programmable gate array (FPGA) are presented and show the viability of this technique.