Jianghua Lu

Research on seamless transfer from CC to CV modes for IPT EV charging system based on double-sided LCC compensation network

In this paper, based on a double-sided LCC compensation network, the leakage inductance equivalent model of the loosely coupled transformer (LCT) is built and the constant current (CC) output with load independent is analyzed in an inductive power transfer (IPT) system. This paper proposes four resonance conditions for achieving constant voltage (CV) output in various load conditions for the compensation network. The Zero Voltage Switching (ZVS) operation for the primary side H-bridge converter can be achieved in CC mode and CV mode to minimize the switching loss. A seamless transfer control strategy is also investigated to realize transmission from CC mode to CV mode for IPT EV (electric vehicle) charging system. An IPT EV system with 3.3 kW transmission power is built. The theoretical analyses are confirmed by simulation and experiment results.

Parameters Design Method of Magnetic Coupled Coil in ICPT System

The LCL compensation structure at primary side and LC series or parallel compensation network at secondary side of the loosely coupling transformer have been widely researched in inductive coupled power transfer (ICPT) system. In this paper, the parameters of the magnetic coupled coil based on multi-resonant SS or SP compensation network in ICPT system was studied. And different optimization analytical methods for SS and SP compensation network were proposed. The proposed method is studied based on Maxwell 3D Finite Element Analysis (FEA) software for an ICPT system with up to 3.3kW output power for electric vehicles (EV) charger. The proposed parameters design method was verified from simulation results.

Impact of the wire tightness degree on circular pad with different coil size in IPT system

This paper intends to evaluate the impact of the wire tightness degree on circular pad with different Archimedean spiral coil size in Inductive Power Transfer (IPT) system. The effect mainly focuses on the sensibility of coupling coefficient to misalignment and gap variation with constant self-inductance when the dimension of the secondary coil is fixed. In this paper, the larger outer diameter of primary coil with constant inner diameter, which means a looser spiral coil, the less sensitive coupling coefficient tends to be. Besides, the larger inner diameter of primary coil with fixed outer diameter, that is, a tighter spiral coil, tends to have a less sensitive coupling coefficient. The models are built and simulated by Finite Element Analysis (FEA) tool, and the experimental data are proved to have a good agreement with simulation results.

Realization of CC and CV Mode in IPT System Based on the Switching of Doublesided LCC and LCC-S Compensation Network

Inductive power transfer (IPT) is the most wide method of wireless power transfer (WPT). In this paper, based on switching double-sided LCC and LCC-S compensation network, constant voltage (CV) output and constant current(CC) output under the conditions of the fixed resonance frequency are realized. The equivalent models of leakage inductance for CC output and mutual inductance equivalent model for CV output are built respectively in IPT system. The zero phase angle (ZPA) between input voltage and input current can be achieved in both CC mode and CV mode to achieve high efficiency. A wireless power transfer system with 3.3 kW is built, which validates the proposed theory.

Design and research of a double-sided flux coupler in inductive power transfer system

Inductive Power Transfer (IPT) has proved its capability as a safe, convenient and efficient solution for electric vehicle (EV) charging systems through loosely coupled transformer. Transformer with double-sided windings is expected to be more compact and lightweight than transformer with single-sided windings. In this paper, a solenoid double D (SDD) coil is proposed to have a good interoperability with the double D (DD) coil and the unipolar coil. To ensure high power transfer efficiency, tolerance for different gap variation and horizontal misalignment conditions are investigated in IPT systems. A 3D finite element modeling tool, Maxwell, is used to simulate all the models presented in this paper.