This paper proposes a non-isolated converter topology capable of achieving a wide output voltage range (200 V to 1000 V). This design addresses the limitations of traditional two-stage isolated and single-stage chargers, where the use of high-frequency resonant converters often restricts the power density and narrows the output voltage range. The proposed topology integrates a buck-stage rectifier circuit with a three-level DC/DC boost stage. To ensure high-efficiency operation and prevent redundant high-frequency switching, a coordinated modulation strategy is developed. When the system operates in buck mode, the high-frequency switches in the boost stage are clamped; when in boost mode, the buck-stage switches are clamped; and during transition mode, both stages coordinate their switching behavior based on the required output voltage. This modulation strategy ensures that the minimum number of high-frequency switches are active at any given time, thereby reducing switching losses caused by hard switching and enabling a smooth transition across the entire output voltage range. Simulation results validate the feasibility and effectiveness of the proposed topology and control method.

In this paper, a multiple-channel wireless power transfer system with anti-interference capability is proposed to provide simultaneous wireless power and data transfer (SWPDT). Two rectangular coils and two DD coils are used for double-channel power transmission, while two other DD coils are used for single-channel data transmission. The crosstalk interference between power and data transfer channels can almost be neglected due to the decoupled design. The design principle of the decoupled coils is illustrated and verified by the finite element method. The circuit topology analysis of the power transfer channel and the data transfer channel based on amplitude shift keying (ASK) is also presented. The effectiveness and anti-interference performance of the system is verified using Simulink. It achieves a data rate of 100kb/s and a power of 2.6kW.

The two-stage wireless charging system is used in various wireless charging application because its power factor correction (PFC) rectifier and the inverter are decoupled from each other and the control is more convenient, but the large number of power switches and bulky electrolytic capacitors results in low power density of the system, so a number of single-stage solutions were put forward. In this paper, a novel single-stage wireless charging system without bulky DC capacitors is proposed to replace the two-stage one, which is composed of only six switches and two diodes. Moreover, a phase-shifting (PS) modulation scheme is proposed based on this single-stage topology, which can realize power regulation, PFC, and soft switching simultaneously. Finally, a simulation prototype is built to verify its effectiveness.

In order to meet a variety of applications, it is imperative to develop new DC-DC topologies with specified voltage conversion ratio. Flux Balance Equations (FBE) is a popular way to solve this problem. Because it can synthesize a topology class covering all the DC-DC topologies satisfying the voltage ratio and can be computer-assisted. The main problem is that it's difficult to determine which topology to choose from the class. The proposed method can obtain the voltage and current of each branch in topology. Then comparing the volume of magnetic core from each topology will become easier. In this way, excellent topologies with smaller magnetic core and higher power density are selected conductively. Firstly, The FBE of each inductor is normalized to ensure to use the same voltage reference direction. Secondly, the relationship of voltage or current between the branches and output is established taking duty cycle as medium. The minimum values of inductors are allowed to be calculated based on above condition when the convertors operate in continuous conduction mode (CCM). Finally, some individuals in the topology class are recommended to be adopted, for the lower minimum of inductor threshold leads to the less consumption of magnetic core. All the work carried out can also be computer-assisted.

Wireless electric vehicle (EV) charger has become increasingly popular because of its improved convenience and safety and its advantage of smaller green-house gas (GHG) emissions. The power control method of the wireless power transfer (WPT) system has great impact on the performance of the charger. In order to simplify the power electronics converters and improve the reliability of the system closed-loop control, a novel secondary-side power control method by adding a pair of bidirectional switches is presented for the wireless EV charger. The proposed control method, which is applied on a double-side LCC compensated wireless power transfer system, is analyzed based on the fundamental harmonic approximation (FHA) approach. The relationship between the controlled duty cycle of the secondary switches and the output power is derived and discussed. The total harmonic distortion (THD) of the input current is also calculated to estimate the influence of the duty cycle on the primary side. A prototype of the WPT system with the proposed control method has been built and tested, and the confirmatory experiment is also presented to validate the theoretical analysis.

Wireless power transfer (WPT) using double-sided LCC compensation features with a proportional relation between input voltage and output current, which is load independent. It lays a solid base for primary-side DC/DC control. In this paper, a novel switching converter control strategy — one cycle control (OCC) combined with proportion differentiation (PD) is proposed to form a robust, fast and precise control for primary-controlled WPT system. The OCC-PD is compared with PID and conventional OCC using Switching Flow-Graph technique. The dynamic responses of different control strategies applied in buck converter connected with a resistor and with WPT stage as the load are analyzed respectively, which guides the design of the proposed control strategy. Finally, the OCC-PD applied in single-stage buck converter and two-stage primary-controlled WPT system is carried out in Matlab/Simulink environment to verify the theoretical analysis, which confirms the superiorities of the proposed OCC-PD strategy.