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In this article, a novel full-feedforward (FF) technique is introduced to lessen the effect of grid voltage distortion on injected current from the multiparallel grid-tied inverters. In this technique, the feedforward transfer function is applied to only one of the system inverters known as the target inverter. Hence, the investment cost for designing and implementing the FF technique is remarkably reduced. The proposed technique is based on introducing a virtual negative admittance at the target inverter to cancel the total parallel admittance of the system. Moreover, the reasons and conditions of instability, caused by the conventional FF techniques, are fully explored in this article. Then, by modifying the conventional FF techniques, a feedforward transfer function is proposed, which guarantees the strong dynamic performance of the system. Ultimately, an additional solution is devised to ensure a desirable grid voltage harmonic rejection ability of the proposed FF technique. Simulation and experimental results verify the validity of the proposed FF technique for a system consisting of two identical parallel grid-tied inverters.

In this article, a new technique of synchronized sampling to estimate the transferred power in wireless power transfer (WPT) systems is proposed. Defining demand factor as a criterion linking unknown receiver parameters to the transferred power, it can be estimated by measuring the front-end variables of the transmitter LCC compensating network. Moreover, with the use of this technique, one does not need to know how the mutual inductance or load varies. As the demand factor is directly linked to the transferred power, the estimation of the demand factor can be considered as an increasingly effective way to control the flow of power in WPT systems. To prove the validity of this approach, a WPT system equipped with an LCC network to compensate the transmitter, and a series capacitor to compensate the receiver, is experimentally built and tested, and the results show a close consistency between the measured demand factor and the transferred power.

Expandable and flexible wireless power transfer (WPT) systems have been in demand in numerous industry applications, especially for dynamic chargers in electric vehicles. Those systems, however, bring about certain technical issues such as modulation technique and topology of the transmitter side, and transferred power profile of the transmitters. In this article, a new converter topology to drive closely spaced segmented dynamic wireless power transfer (DWPT) systems is proposed. The proposed converter can be expanded to cater for different number of transmitters, and it can provide a uniform transferred power profile throughout the path of transmitter coils, known as track. Furthermore, this article focuses on analyzing the operation of the converter and the effect of closely spaced transmitters over its operation. To show the effectiveness of the proposed topology and its modulation technique, the converter is simulated and experimentally tested using a laboratory prototype. The results are compared and analyzed, and their close agreement shows the validity of the proposed technique.

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.

In this paper, a new method for dynamic wireless power transfer is presented. It is proposed that to reduce the size and weight of the pickup which is fixed on the bottom side of the electric vehicle chassis, and to increase the efficiency, a multi transmitter wireless power transfer system driven by an expandable N-Legged Converter (NLC) can be used. Along with these features, a uniform transferred power and efficiency profiles, simplicity of the converter and its modulation method are other remarkable features of this method. To show the feasibility of the proposed method, magnetics of the system is simulated in Maxwell and the converter is modelled in MATLAB. © 2018 IEEE.

This paper presents a new method to drive transmitters used in dynamic wireless power transfer for Electric Vehicle (EV) applications. Using a three-legged converter, transmitter currents can be controlled so that by reducing the current in the weakly coupled transmitters with the pickup, the efficiency can be increased, and the null points of transferred power to the load can be removed. Along with these features, this technique boasts a simple coil in the receiver and lower number of switches to drive the transmitters. To show the validity of this approach, mathematical analysis and simulation results are presented.