Charger Prototype Research Articles

Experimental study of a new corona-based unipolar aerosol charger

A corona-based unipolar aerosol charger has been constructed, and its performance has been systematically evaluated. The prototype consists of completely separated corona ionization and charging chambers. With this configuration the electrostatic loss of charged particles is eliminated, and particle loss by diffusion and the space charge effect is minimized by the angular injection of the ionizer flow and the rapid exit of charged particles. The charger performance was optimized by varying different operational parameters, i.e., total and ionizer flowrates, and ion concentration. It was found that operation with one corona ionizer gave higher extrinsic charging efficiency than operation with two ionizers. The corona-discharge current has negligible effect on the charging performance. Operating the charger at a total flowrate of 5 lpm, with 1.0 lpm flow in each of the two ionizers, gave the highest extrinsic charging efficiency. Further, the performance of prototype charger was not compromised even at a total flowrate of 10 lpm. The charger provides higher extrinsic charging efficiency than other corona-based unipolar chargers. Extrinsic charge distributions for particles of different sizes were at last measured by the tandem-DMA technique.

Zero-Voltage-Switching Multiresonant Three-Level Converters

This paper proposes a family of zero-voltage-switching multiresonant three-level converters (ZVS-MR-TLCs), which are derived by adding a ZVS-MR multiresonant network to the TLCs. The arrangement of a multiresonant network results in the absorption of all the major parasitic components in the resonant circuit, including the switch output capacitor, diode junction capacitor, and transformer leakage inductor. Compared with the two-level multiresonant converters (MRCs), the proposed converters achieve ZVS in a wider load range and reduce the voltage stress on the switches and diodes, and the filter can be reduced significantly. The Buck ZVS-MR-TLC is taken as the example to illustrate the operation principle, characteristics, and advantages over the two-level Buck ZVS-MRC. An interleaved control strategy and a voltage control of the flying capacitor for the new converters are presented in detail. A 1-kW high-voltage-input railway charger prototype converter is built in our lab to verify the theoretical analysis and the effectiveness of the interleaved control strategy and flying capacitor voltage control method

ALAT PENGISI BATERAI TELEPON SELULER BERBASIS ENERGI MATAHARI

Cellular phone battery recharging using conventional energy source, i.e. electricity supply, has disadvantage within the areas that are not covered by electricity grids (PLN). This research designed a prototype of cellular phone battery charger based on solar energy. Some solar cells were used to convert solar energy into electricity currents that fluctuated due to variation of sun light with 10.11 volt maximum voltage. Reserved batteries were used for temporary storage of the generated currents. Boost converter was used to stable the output voltage about 8 volt with input above 3 volt. The test showed that there was a variation on nominal voltage increase of the phone battery. At sunny condition and while the reserve battery was fully charged, Nokia N3350 battery voltage increased to 0.03 Volt in 30 minutes. For Siemens C45 battery recharging, the system must be reconfigured. The reconfigured system increased nominal battery voltage of 0.2 Volt in 2 hours.

Fuzzy-controlled Li-ion battery charge system with active state-of-charge controller

A fuzzy-controlled active state-of-charge controller (FC-ASCC) for improving the charging behavior of a lithium-ion (Li-ion) battery is proposed. The proposed FC-ASCC is designed to replace the general constant-voltage charging mode by two kinds of modes: sense and charge. A fuzzy-controlled algorithm is built with the predicted charger performance to program the charging trajectory faster and to keep the charge operation in a proposed safe-charge area (SCA). A modeling work is conducted for analyzing and describing the Li-ion battery in charging process. A three-dimensional Y-mesh diagram for describing the charging trajectories of the proposed FC charger is simulated. A prototype of a Li-ion battery charger with FC-ASCC is simulated and realized to assess the predicted charging performance. Experiment shows that the charging speed of the proposed FC charger compared with the general one increases about 23% and the charger can safely work in the SCA.

Nonconventional on-board charger for electric vehicle propulsion batteries

Electric vehicles (EVs) are needed in densely populated urban areas to reduce air pollution. Battery chargers are needed to supply DC voltage to charge the high-energy battery parks used in EVs. This paper deals with an on-board battery charger arrangement that is fully based on the use of the power components of the EV motor drive. Desired features for EV battery chargers such as minimum volume, low cost, high efficiency, and high reliability are fully matched by means of the proposed solution. The proposed on-board charger arrangement has been installed on an electric scooter prototype being developed for the Far East markets. Design analysis and experimental results of the on-board charger prototype are presented.

A one-converter contactless charger for electric vehicles

A simple and reliable contactless battery charger for electric vehicles is proposed. Its feature is a unitized power factor correcting (PFC) converter and a high-frequency inverter (HFI) where the low-side switch of the HFI also works as the boost switch of the PFC in discontinuous conduction mode, which results in a high input power factor and low harmonic distortion without any feedforward control. The exiting current of the inductive connector, compliant with SAEJ1773, works effectively to make the converter operate in zero voltage switching (ZVS) condition. Another feature is that the charger is controlled by a single magnetically coupled variable frequency oscillator developed by the authors. This paper analyzes the circuits, gives a design example, describes the inductive connector and the oscillator, and presents experimental results. A 1.7-kW output prototype charger achieved a charging efficiency of 87.4% for total one cycle charging, an overall efficiency of 90% at heavy load, and an input power factor of over 98%. © 2000 Scripta Technica, Electr Eng Jpn, 132(2): 73–81, 2000

One Converter Type Contact-less Charger for Electric Vehicles

A simple and reliable contact-less battery charger for electric vehicles is proposed. It's feature is one body of a power factor correction(PFC) converter and a high frequency inverter(HFI) where the low side switch of an HFI works also as the boost switch of an PFC in discontinuous conduction mode which results in high input power factor and low harmonic distortion without any feed-forward control. The exiting current of the inductive connector, complied with SAEJ1773, effectively works to make the converter operating in ZVS condition. Another feature is that the charger is controlled by only one magnetically coupled variable frequency oscillator which was developed by the authors. This paper analyzes the circuits, gives a design example, shows the inductive connector and the oscillator, and experimental results. An 1.7kW output prototype charger achieved charging efficiency of 87.4% among total one cycle charging, over all efficiency of 90% at heavy load and over 98% of input power factor.

A multirate digital controller for a 1.5-kW electric vehicle battery charger

This paper describes a power electronic system that, among other possibilities, can be used to charge electric vehicle batteries. A large-signal linear, multirate digital controller for the charging current permits the charger to track and deliver a desired current trajectory for a wide range of loads. This controller simultaneously ensures that the charger draws power from the electric utility with unity power factor. The analytical development of the controller and experimental results from a prototype charger are presented.

Unipolar diffusional charging of fibrous aerosols—Theory and experiment

Models for the unipolar charging of fibers were developed. The theoretical models using idealized geometries—either prolate spheroids or cylinders—and considering both the free-molecular and continuum cases served as a basis for numerical simulations. Simulation results showed that the fibers can carry more charges than equal surface area spheres. In the experimental component of this study, a prototype charger was designed and constructed. The rate of charging was measured as a function of fiber length and charger parameters. It was found that the fiber collection efficiency depends both on charge numbers and the aerodynamic drag of the fiber. The fiber length classification can be achieved by electrostatic precipitation.

An SCR Inverter with an Integral Battery Charger for Electric Vehicles

A thyristor-based inverter/charger for use in electric passenger vehicles is described, and prototype charger test results are presented. A battery charger is included integral to the inverter by using a subset of the inverter power circuit components. The integral charger employs the inverter commutation components as a resonant ac/dc converter rated at 3.6 kW. The resulting charger provides electrical isolation between the vehicle propulsion battery and ac line and is capable of charging a 25-kWh propulsion battery in 8 h from a 220-V ac line. Charger efficiency and power factor at an output power of 3.6 kW are 86 and 95 percent, respectively. The inverter, when operated with a matching polyphase ac induction motor and nominal 132-V propulsion battery, can provide a peak shaft power of 34 kW (45 hp) during motoring operation and 45 kW (60 hp) during regeneration. Thyristors are employed for the inverter power switching devices and are arranged in an input-commutated topology. This configuration requires only two thyristors to commutate the six main inverter thyristors. The combined ac inverter/charger package weighs 47 kg (103 lb).