Wireless Battery Charging System Research Articles

Analysis and Design of a High Frequency Wireless Battery Charging System With Smooth Mode Transition Characteristics

Analysis and Design of a High Frequency Wireless Battery Charging System With Smooth Mode Transition Characteristics

ВИЗНАЧЕННЯ ПАРАМЕТРІВ ОСНОВНИХ ЕЛЕМЕНТІВ БЕЗДРОТОВОГО ЗАРЯДНОГО ПРИСТРОЮ ДЛЯ ЗАРЯДКИ АКУМУЛЯТОРНОЇ БАТАРЕЇ ЕЛЕКТРОМОБІЛЯ

The work has developed a methodology for calculating voltage values on the main elements of the wireless battery charging system, which allows at the design stage of such systems to choose the necessary parameters of coils and an additional high-frequency transformer, while harmonizing the voltage value on the battery with the voltage at the output of the high-frequency inverter. A comparison of the calculation results using the developed methodology with the corresponding results obtained using the developed Simulink-model of the system showed that their maximum discrepancy does not exceed 15%. It is noted that in practice, when developing such systems to match the voltage of the rechargeable battery with the high-frequency inverter, it is possible to either use an additional high-frequency transformer, or choose the necessary ratio of turns of the transmitting and receiving coils. In the latter case, the possibility of high voltage resonance voltage on the coils and capacitive elements should be taken into account, which requires the use of reinforced insulation and the fulfillment of all requirements for the operation of devices at the corresponding high voltage. References 6, figures 3, table 1.

Performance Analysis of Two Receiver Arrangements for Wireless Battery Charging System

Performance Analysis of Two Receiver Arrangements for Wireless Battery Charging System

Widening the Operating Range of a Wireless Charging System Using Tapped Transmitter Winding and Bifrequency Pulse Train Control

In this article, a subharmonics switching technique named bifrequency pulse train (BF-PT) control for wireless battery charging system with tapped transmitter (Tx) winding is proposed to regulate the output power against the variation of load and coupling coefficient. The tapped Tx winding is spilt into two subwindings: subwinding I is connected to the inverter while subwinding II is in open circuit. The charging current and charging voltage can be acquired by measuring the induced current of subwinding I and the induced voltage of subwinding II, respectively, without dual-side communication. BF-PT control, which contains high- and low-frequency pulse trains, can achieve zero voltage switching over a wide operating range. The high- and low-frequency pulse trains are uniformly distributed to suppress the winding current oscillation and to minimize the output voltage ripple. When the coupling becomes weaker and/or light-load conditions, the switches are operated at the subharmonics frequency to further reduce the average switching frequency of the system. To verify the validity of the proposed method, a wireless charging system with 72 V/3 A output is fabricated. The experimental results confirmed that the proposed method is able to maintain constant current and constant voltage output regardless of the load and coupling variations.

Smart border patrol using drones and wireless charging system under budget limitation

Harsh environmental factors surrounding the national borders as well as their extensive length make the use of manned systems for monitoring every location on the border a risky, expensive, and hardly possible task. Smart border patrol using small-size drones may provide significant help in patrolling areas inaccessible to patrol agents, reduce agent response time, and increase the safety of patrol agents working in dangerous regions. However, the short flight duration associated with small-size drones due to battery limitation can be a serious drawback for such a system for seamless surveillance. Therefore, this paper proposes a drone-based continuous surveillance system for border patrol with a dynamic wireless battery charging system that is built onto an electrification line (E-line). To control the maximum time interval between two consecutive flights to a particular section of the border, a permitted revisiting gap is assigned to each location on the border based on its criticality. A multi-objective mixed-integer non-linear programming (MINLP) model is developed to minimize both the total length of the E-line system for the wireless charging system and the number of drones to satisfy the revisiting gap constraint for a secure border patrol. A solution algorithm is proposed to achieve the Pareto-optimal set. This method provides the decision-maker with a set of candidate solutions to choose from based on their priorities and budgetary constraints. We illustrate our method using a case study on a segment of the US-Mexico borderline.

Light-Load Efficiency Optimization for an LCC-Parallel Compensated Inductive Power Transfer Battery Charger

Wireless power transfer (WPT) techniques have gained wide acceptance across a range of battery charging applications such as cell phones, cardiac pacemakers, and electric vehicles. In a wireless battery charging system, a constant current/constant voltage (CC/CV) charging strategy, regardless of the variation of the battery load which may roughly range from a few ohms to several hundred ohms, is typically adopted to ensure the safety, durability, and performance of the battery. However, system efficiency drops significantly as the load increases in CV mode, especially at very light-load conditions. This paper proposes an efficiency optimization method for an LCC-parallel compensated inductive power transfer (IPT) battery charging system without the help of any additional power converter and control method. The equivalent circuit and resonant conditions of the LCC-parallel compensation topology are firstly analyzed to achieve the load-independent CV output at a zero phase angle (ZPA) operating frequency. Over the full range of CV charging mode, the efficiency of the LCC-parallel resonant tank circuit is analyzed and optimized. An IPT battery charger prototype with 48 V charging voltage and 1 A charging current is implemented. A measured DC–DC transfer efficiency of greater than 90.48% is achieved during the whole CV charging profile.

CMOS High-Efficiency Wireless Battery Charging System With Global Power Control Through Backward Data Telemetry for Implantable Medical Devices

A high-efficiency CMOS wireless battery charging system with battery voltage tracking and global power control through the proposed pulsed load-shift keying (PLSK) backward data telemetry technique is designed. The power transmitted from the adaptively controlled power transmitter (ACPT) for battery charging is automatically adjusted with the battery voltage tracking through the PLSK backward data telemetry. Therefore, the generated rectifier output voltage is only slightly larger than battery voltage and tracks with battery voltage during the charging time of linear battery charger. Experimental result shows that the average receiver efficiency with battery voltage tracking from 3.3 V to 4.2 V and global power control is 90.9% which is 14.9% higher than that without these techniques and 28.9% higher than that in the prior work. The measured power loss is 8 mW (4.44%) under the maximum output power of 180 mW and with the PLSK data rate of 211 kbps. The proposed wireless battery charging system with a single pair of coils at the resonant frequency of 13.56 MHz is suitable for the applications of implantable medical devices.

Solar Panel-based Wireless Battery Charging System using Fuzzy Control Method

Rapid technological development leads to the growth of electronic devices powered by batteries. This requires a simple, fast and safe battery charging system. In this study, we have designed and realized a wireless battery charging system supplied by solar panel using the fuzzy control method. This system is equipped with solar tracking to produce optimal electric power. Furthermore, fuzzy control system is applied to determine the amount of charging voltage by taking into account the temperature of the battery. The experimental results show that the solar tracking system can improve the performance of solar panel. The system always detects the temperature of the battery and will reduce the voltage value during the charging process as the temperature increases. This battery charging system will also automatically decrease the charging voltage when the battery voltage approaches the maximum value. This system is expected to be used as a fast battery charging system without affecting the battery life.

Evaluation of losses in a secondary-side controlled wireless battery chargingsystem

Secondary-side controlled inductive power transfer (IPT) systems are easy to control compared to primary and dual-side control methods, and more importantly, they do not require wireless communication between primary and secondary sides. In this paper, a wireless battery charging system based on secondary-side controlled IPT is analyzed and presented in detail. The proposed control method relies on the detection of the secondary coil current and the transferred power can be fully controlled by the secondary-side active rectifier with reduced number of power switching devices. The steady-state performance of the IPT system is evaluated using a fundamental harmonic analysis method for resistive and reactive control modes of the active rectifier by taking the converter losses into account. Theoretical and simulation results of the designed system are validated by experimental results obtained from the implemented laboratory prototype for charging of a 96-V lead-acid battery.

An Improved Wireless Battery Charging System

This paper presents a direct wireless battery charging system. The output current of the series-series compensated wireless power transfer (SS-WPT) system is used as a current source, and the output voltage of AC-DC converter controls the current source. Therefore, the proposed wireless battery charging system needs no battery charging circuit to carry out charging profiles, and can solve space constraints and thermal problems in many battery applications. In addition, the proposed wireless battery charging system can implement easily most other charging profiles. In this paper, the proposed wireless battery charging system is implemented and the feasibility is verified experimentally according to constant-current constant-voltage charging profile or multi-step current charging profile.

Development and analysis of S/S resonant wireless system for electric two wheeler battery charging

In recent years wireless power transfer (WPT) for electric vehicle battery charging is a developing technology. It allows electric power transfer without any physical connection between a transmitter and a receiver over a certain distance. However, to improve the power transfer capability over a longer distance, the coupled coils must be compensated with an appropriate capacitor. This paper deals with implementation and analysis of series/series resonant wireless battery charging system for electric two-wheeler at resident parking garages or at public parking places. The charging profiles such as charging current and time with various misalignment conditions of the coupled coils are presented and also the efficiency of the system is analysed. The experimental result conveys the appropriateness of the proposed design. Hence it can be implemented for real-time heavy-duty vehicles.

Development and analysis of S/S resonant wireless system for electric two wheeler battery charging

In recent years wireless power transfer (WPT) for electric vehicle battery charging is a developing technology. It allows electric power transfer without any physical connection between a transmitter and a receiver over a certain distance. However, to improve the power transfer capability over a longer distance, the coupled coils must be compensated with an appropriate capacitor. This paper deals with implementation and analysis of series/series resonant wireless battery charging system for electric two-wheeler at resident parking garages or at public parking places. The charging profiles such as charging current and time with various misalignment conditions of the coupled coils are presented and also the efficiency of the system is analysed. The experimental result conveys the appropriateness of the proposed design. Hence it can be implemented for real-time heavy-duty vehicles.

Autonomous Wireless Self-Charging for Multi-Rotor Unmanned Aerial Vehicles

Rotary-wing unmanned aerial vehicles (UAVs) have the ability to operate in confined spaces and to hover over point of interest, but they have limited flight time and endurance. Conventional contact-based charging system for UAVs has been used, but it requires high landing accuracy for proper docking. Instead of the conventional system, autonomous wireless battery charging system for UAVs in outdoor conditions is proposed in this paper. UAVs can be wirelessly charged using the proposed charging system, regardless of yaw angle between UAVs and wireless charging pad, which can further reduce their control complexity for autonomous landing. The increased overall mission time eventually relaxes the limitations on payload and flight time. In this paper, a cost effective automatic recharging solution for UAVs in outdoor environments is proposed using wireless power transfer (WPT). This research proposes a global positioning system (GPS) and vision-based closed-loop target detection and a tracking system for precise landing of quadcopters in outdoor environments. The system uses the onboard camera to detect the shape, color and position of the defined target in image frame. Based on the offset of the target from the center of the image frame, control commands are generated to track and maintain the center position. Commercially available AR.Drone. was used to demonstrate the proposed concept which is equppied with bottom camera and GPS. Experiments and analyses showed good performance, and about 75% average WPT efficiency was achieved in this research.

A Novel Type of Wireless V2H System with a Bidirectional Single-Ended Inverter Drive Resonant IPT

Electric vehicles (EV) offer promise as an effective solution to environmental problems. One of the keys to their successful diffusion is the provision of adequate battery charging infrastructure. In order to create a charging infrastructure by installing equipment in such as locations as carports in private homes, the wireless battery charging system is very suitable. EVs can be used in smart house systems to supplement the energy storage. This vehicle to home (V2H) system essentially requires a bidirectional power transfer feature between the EV and home. This paper presents a new bidirectional inductive power transfer (IPT) system for wireless V2H with simplest components and low cost aiming at wide diffusion for home use. Proposed is a novel type of bidirectional wireless EV charging system with an efficient and compact type single-ended quasi-resonant high-frequency inverter for V2H.

Wide input range, high-efficiency magnetic resonant wireless power receiver

This article presents a full-CMOS receiver for magnetic resonant wireless battery charging system. A wide-input range CMOS multi-mode active rectifier is proposed for a magnetic resonant wireless battery charging system. The configuration is automatically changed with respect to the magnitude of the input AC voltage. The output voltage of the multi-mode rectifier is sensed by a comparator. Furthermore, the configuration of the multi-mode rectifier is automatically selected by switches as original rectifier mode, one-stage voltage multiplier or two-stage voltage multiplier mode. As a result, a rectified DC output voltage is from 7.5 to 19 V for an input AC voltage of 5–20 V. This chip is implemented using 0.35 μm BCD technology with an active area of around 5 × 2.5 mm2. When the magnitude of the input AC voltage is 10 V, the power conversion efficiency of the multi-mode active rectifier is about 94%.The efficiency of the receiver is about 60% when the distance between the transmitter and receiver is about 1 m.

Automatic power controlled, load compensated magnetic resonant wireless power transmitter

As compared to other wireless transfer mechanism, like the inductive coupling method, magnetic resonance-based wireless power transfer can achieve power transfer over a larger distance. However, as the transmission range increases, the change in the load impedance lowers the transmission efficiency in the currently available magnetic resonance-based wireless power transmitters. This article presents a CMOS transmitter for magnetic resonant wireless battery charging system. A class-E power amplifier (PA) with an automatic power control loop and load compensation circuit is proposed to improve the power efficiency. The transmitted power is controlled by adjusting the signal applied to the gate of the power control transistor. In addition, a parallel capacitor is also controlled to enhance the efficiency and compensate for the load variation. The proposed design is implemented using 0.35 μm BCD technology with an active area of around 5 mm × 2.5 mm. The transmitter provides an output power control range of 9–30.2 dBm. The measured maximum power efficiency of the PA is 70.2%.

A high efficiency transmitter and receiver for magnetic resonant wireless battery charging system in 0.35 μm BCD

This paper presents a transmitter and receiver for magnetic resonant wireless battery charging system. In the receiver, a wide-input range CMOS multi-mode active rectifier is proposed for a magnetic resonant wireless battery charging system. The configuration is automatically changed with respect to the magnitude of the input AC voltage. The output voltage of the multi-mode rectifier is sensed by a comparator. Furthermore, the configuration of the multi-mode rectifier is automatically selected by switches as original rectifier mode, 1-stage voltage multiplier or 2-stage voltage multiplier mode. As a result, a rectified DC voltage is output from 7.5 to 19 V for an input AC voltage of 5---20 V. In the transmitter, a class-E power amplifier (PA) with an automatic power control loop and load compensation circuit is proposed to improve the power efficiency. The transmitted power is controlled by adjusting the signal applied to the gate of the power control transistor. In addition, a parallel capacitor is also controlled to enhance the efficiency and compensate for the load variation. This chip is implemented using 0.35 μm BCD technology with an active area of around 5,000 × 2,500 μm. When the magnitude of the input AC voltage is 10 V, the power conversion efficiency of the multi-mode active rectifier is about 94 %.The maximum power efficiency of the receiver is about 70 %. The transmitter provides an output power control range of 10---30.2 dBm. The maximum power efficiency of the PA is 71.5 %.

Wireless battery charging system for existing hearing aids using a dynamic battery and a charging processor unit

A rechargeable battery which may be used with most presently available hearing aids (or other appliances) with no modification to the existing hearing aid is needed in order to use the described wireless charging system. The battery may be known a “Dynamic battery” as the battery is actively charged by means of an inductor circuit built into the battery housing itself or added onto the battery. The hearing aid may simply be placed within the charger housing (or cradle) to charge the battery. No electrical connection by either wires or electrical contacts is needed to recharge the battery, which is located inside the hearing aid housing. Moreover, the battery need not be removed from the hearing aid (or other appliance).