Capacitive Power Transfer System Research Articles

Design of a stagger‐tuned high‐power low‐stress capacitive wireless power transfer system

AbstractCapacitive power transfer (CPT) has emerged as a promising alternative to traditional inductive methods. CPT offers advantages like cost‐effectiveness, reduced weight and volume, and greater tolerance to alignment errors. However, the high‐Q resonant circuits used as matching networks can be susceptible to high voltage stress, especially when transmitting substantial power. Consequently, designing matching networks for CPT systems necessitates consideration of multiple parameters, including practical constraints such as component losses and breakdown thresholds. In this work an innovative algorithm is presented for designing practical matching networks in CPT systems. The algorithm conducts a methodical search of potential solutions, and converges on component values that maximize power transfer efficiency whilst also minimizing component voltage stress. The proposed algorithm is demonstrated theoretically and experimentally.

Multi-MHz Inductive and Capacitive Power Transfer Systems With PCB-Based Self-Resonators

Multi-MHz Inductive and Capacitive Power Transfer Systems With PCB-Based Self-Resonators

Design of Stabilizing Network for Capacitive Power Transfer Transmitter Operating at Maximum Power Transfer Limiting the Voltage Gain in Resonant Capacitors

Capacitive power transfer (CPT) is a technology that is emerging as an alternative to inductive power transfer (IPT) in applications requiring low to medium power. A great interest has been developed in the implementation of CPT systems in battery charging systems, where a condition to compete with IPT systems is the need to increase the power transfer in the CPT systems without significant losses. This paper puts forth a design methodology for a stabilizing network, which has been applied to a CPT system. This methodology has been developed through impedance analysis of the circuit, in order to achieve maximum power transfer, with total gains of voltage and current reaching a value close to unity. The methodology allows for the calculation of the value of the components of the stabilizing network, which has been designed with the objective of stabilizing the resonant frequency against changes in the capacitance of the transmission plates. To validate the design procedure, an experimental prototype was developed at 25 W and an operational frequency of 1.55 MHz. The results obtained validate the design methodology.

Enhancing efficiency in capacitive power transfer: exploring gap distance and load robustness

In this paper, the capacitive power transfer (CPT) technology is used as an alternative to inductive power transfer (IPT). CPT relies on electric fields that are not sensitive to the presence of any metals, utilizes metal electrodes for power transfer, and is less bulky compared to IPT. The proposed CPT system utilizes a Class-E resonant inverter with a double-sided inductor-capacitor (LC) matching circuit which operates at an optimum load, with a duty cycle, D=0.5 to gain an output power, W and efficiency, η=84.6%. The proposed CPT system enhances the system’s efficiency as compared to the past research while preserving the zero-voltage switching (ZVS) condition within a wider load range from 50 Ω to 1,316 Ω. This paper also shows that the proposed CPT system is less sensitive to load and coupling variations. Finally, the rate of power dissipated at varied load resistances, has been derived successfully to determine the sensitivity level of the proposed CPT systems toward load variations. These equations are then validated by plotting the efficiency graphs based on load and coupling variations.

A capacitive power transfer system with LCL primary compensation for very‐low‐power portable devices

AbstractThis paper investigates and technically demonstrates a capacitive power transfer (CPT) system applicable to the charging of emerging very‐low‐power portable devices. The constant‐current operation of the primary LCL compensation in CPT is implemented and analysed to simplify the system design process and minimize the configuration on the receiving side. Additionally, the system design considerations for the capacitive coupler and the diode rectifier are presented based on the battery charging specifications. All the design concepts and considerations are validated through experimentation with a 13.56 MHz CPT system, which achieves load‐independent constant‐current output from full‐load to light‐load (one‐tenth of the full load) charging operations.

Primary side control technique for capacitive power transfer system without any wireless feedback

The output voltage of capacitive power transfer (CPT) system will change if the load resistance is varied. This paper presents a method to regulate the output voltage using a controller that is located on the primary side, known as the primary side control technique. It does not require any additional components and wireless feedback, which lowers the cost and complexity of CPT system compared to the conventional control technique. Instead of directly measuring the output voltage on secondary side, it is estimated through the measured capacitor voltage on primary side. Modified sine wave control of the full-bridge inverter is adopted to regulate the output voltage. The proposed control technique is validated by the simulation via PSIM software using the practical parameters of capacitive coupler presented in the literature. Simulation results of the output voltage control against the step change in desired output voltage and load resistance indicate the performance of proposed control technique.

Capacitive Wireless Power Transfer System with a 3D-Functional Coupler for Maintenance-Free Industrial Robots

Capacitive Wireless Power Transfer System with a 3D-Functional Coupler for Maintenance-Free Industrial Robots

Multiband Adaptive Impedance Compensation Methods for Spatially Robust Capacitive Power Transfer Systems

Multiband Adaptive Impedance Compensation Methods for Spatially Robust Capacitive Power Transfer Systems

Design of a Static Capacitive Power Transfer System With Six-Plate Coupler for Electric Vehicle Wireless Charging

Design of a Static Capacitive Power Transfer System With Six-Plate Coupler for Electric Vehicle Wireless Charging

Design of Capacitive Power Transfer System with Small Coupling Capacitance for Wireless Power Transfer

Wireless power transfer systems play an important role in the application of modern power supply technology. Wireless charging has been widely used in portable devices such as smartphones, laptops, and even some medical devices. Higher system efficiency can be achieved while reducing costs. This article describes the design of a capacitive power transfer (CPT) system using the Class-E amplifier method. When the capacitance of the coupling plate is small, the operation of Class-E amplifiers under Zero-Voltage-Switching (ZVS) conditions is very sensitive to their circuit parameters. By adding an additional capacitor to the Class-E amplifier, the coupling capacitance can be increased, resulting in better circuit performance. The high efficiency of the Class-E amplifier is verified by simulation and experimental results.

Capacitive Wireless Power Transfer System with Misalignment Tolerance in Flowing Freshwater Environments

Capacitive Wireless Power Transfer System with Misalignment Tolerance in Flowing Freshwater Environments

Nonisolation Model and Load Virtual-Grounding Design Method for Capacitive Power Transfer System With Asymmetric Four-Plate Coupling Interface

Nonisolation Model and Load Virtual-Grounding Design Method for Capacitive Power Transfer System With Asymmetric Four-Plate Coupling Interface

Compact inductive and capacitive combined wireless power transfer system for unmanned aerial vehicle applications

Compact inductive and capacitive combined wireless power transfer system for unmanned aerial vehicle applications

Analysis and Implementation of Underwater Single Capacitive Coupled Simultaneous Wireless Power and Bidirectional Data Transfer System

Analysis and Implementation of Underwater Single Capacitive Coupled Simultaneous Wireless Power and Bidirectional Data Transfer System

Single-Sided Compensation Network Design Method for Capacitive Power Transfer System Considering Coupling Variation

Single-Sided Compensation Network Design Method for Capacitive Power Transfer System Considering Coupling Variation

5-kW, 96.5% Efficiency Capacitive Power Transfer System with A Five-plate Coupler: Design and Optimization

5-kW, 96.5% Efficiency Capacitive Power Transfer System with A Five-plate Coupler: Design and Optimization

A Multiple Independent-Load Output Capacitive Power Transfer System With High Coupler Misalignment-Tolerance for Railway Applications

A Multiple Independent-Load Output Capacitive Power Transfer System With High Coupler Misalignment-Tolerance for Railway Applications

Stabilization Control of Output Voltage for Segmented Dynamic Capacitive Power Transfer System Based on Partial Power Processing

Stabilization Control of Output Voltage for Segmented Dynamic Capacitive Power Transfer System Based on Partial Power Processing

A Novel Compensation Circuit of the Capacitive Power Transfer System With High Performance of Anti-Misalignment

A Novel Compensation Circuit of the Capacitive Power Transfer System With High Performance of Anti-Misalignment

Double-sided LC-compensated capacitive wireless power transfer system with admittance-based matching networks

Double-sided LC-compensated capacitive wireless power transfer system with admittance-based matching networks