Efficient Frequency and Duty Cycle Control Method for Fast Pulse-Charging of Distributed Battery Packs by Sharing Cell Status

This paper proposes a Duty-Cycle (DC) control method in order to improve the Packet Delivery Ratio (PDR) for IEEE 802.15.4-compliant heterogeneous Wireless Sensor Networks (WSNs). The proposed method controls the DC so that the buffer occupancy of sensor nodes is less than 1 and assigns DC to each sub-network (sub-network means a network consisting of a router node and its subordinate nodes). In order to use the appropriate DC of each sub-network to obtain the high PDR, this paper gives analytical expressions of the buffer occupancy. The simulation results show that the proposed method achieves a reasonable delay and energy consumption while maintaining high PDR.

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An Investigation of the Ward Leonard System for Use in a Hybrid or Electric Passenger Vehicle

Volume 1: 15th International Conference on Advanced Vehicle Technologies; 10th International Conference on Design Education; 7th International Conference on Micro- and Nanosystems ◽

10.1115/detc2013-12051 ◽

2013 ◽

Author(s):

Cody L. Telford ◽

Robert H. Todd

Keyword(s):

Electric Vehicles ◽

Control Method ◽

Control Factor ◽

Operating Voltage ◽

Battery Management ◽

Passenger Vehicle ◽

Ac Motors ◽

Design Alternatives ◽

Battery Packs ◽

Electronic Controller

Since the early 1900’s demand for fuel efficient vehicles has motivated the development of electric and hybrid electric vehicles. Unfortunately, some components used in these vehicles are expensive and complex. Todays consumer electric vehicles use dangerously high voltage, expensive electronic controllers, complex battery management systems and AC motors. The goal of this research at BYU is to increase safety by lowering the operating voltage and decrease cost by eliminating expensive controllers and decrease the number of battery cells. This paper specifically examines the use of a Ward Leonard Motor Control system for use in a passenger vehicle. The Ward Leonard System provides an alternative control method to expensive and complex systems used today. A Control Factor metric was developed as a result of this research to measure the Ward Leonard System’s ability to reduce the size and cost of the electronic controller for application in an EV or HEV. A bench top model of the Ward Leonard system was tested validating the Control Factor metric. The Ward Leonard system is capable of reducing the controller size by 77% and potentially reducing its cost by this amount or more. This work also provides performance characteristics for automotive designers and offers several design alternatives for EV and HEV architectures allowing a reduction in voltage, the use of AC inverters, AC motors, expensive controllers and high cell count battery packs.

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Proposed Topology for Voltage Sag Mitigation with New Control Strategy

Iraqi Journal for Electrical And Electronic Engineering ◽

10.37917/ijeee.15.2.15 ◽

2019 ◽

Vol 15 (2) ◽

pp. 138-144

Author(s):

Adnan Diwan ◽

Khalid Abdulhasan

Keyword(s):

Duty Cycle ◽

Control Strategy ◽

Output Voltage ◽

System Analysis ◽

Control Method ◽

Boost Converter ◽

Voltage Sag ◽

Voltage Sags ◽

Long Duration ◽

Simulation Results

voltage sags represent the greatest threat to the sensitive loads of industrial consumers, the microprocessor based-loads, and any electrical sensitive components. In this paper, a special topology is proposed to mitigate deep and long duration sags by using a modified AC to AC boost converter with a new control method. A boost converter is redesigned with a single switch to produces an output voltage that is linearly proportional to the duty cycle of the switch. On the other hand, the proposed control system is based on introducing a mathematical model that relates the missing voltage to the duty cycle of the boost converter switch. The simulation results along with the system analysis are presented to confirm the effectiveness and feasibility of the proposed circuit.

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A Non-Dissipative Equalizer with Fast Energy Transfer Based on Adaptive Balancing Current Control

Electronics ◽

10.3390/electronics9121990 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1990

Author(s):

Shun-Chung Wang ◽

Chun-Yu Liu ◽

Yi-Hua Liu

Keyword(s):

Energy Transfer ◽

Duty Cycle ◽

Nonlinear Behavior ◽

Lithium Ion ◽

Current Control ◽

Test Results ◽

Voltage Difference ◽

Battery Packs ◽

Circuit Component ◽

Transfer Stage

In this study, an active inductive equalizer with fast energy transfer based on adaptive balancing current control is proposed to rapidly equilibrate lithium-ion battery packs. A multiphase structure of equalizer formed by many specific parallel converter legs (PCLs) with bidirectional energy conversion serves as the power transfer stage to make the charge shuttle back and forth between the cell and sub-pack or sub-pack and sub-pack more flexible and efficient. This article focuses on dealing with the problem of slow balancing rate, which inherently arises from the reduction of balancing current as the voltage difference between the cells or sub-packs decreases, especially in the later period of equalization. An adaptive varied-duty-cycle (AVDC) algorithm is put forward here to accelerate the balance process. The devised method has taken the battery nonlinear behavior and the nonideality of circuit component into consideration and can adaptively modulate the duty cycle with the change of voltage differences to maintain balancing current nearly constant in the whole equilibrating procedure. Test results derived from simulations and experiments are provided to demonstrate the validity and effectiveness of the equalizer prototype constructed. Comparing with the conventional fixed duty cycle (FDC) method, the improvements of 68.3% and 8.3% in terms of balance time and efficiency have been achieved.

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Control of a Fault-Tolerant Photovoltaic Energy Converter in Island Operation

Energies ◽

10.3390/en13123201 ◽

2020 ◽

Vol 13 (12) ◽

pp. 3201

Author(s):

Marino Coppola ◽

Pierluigi Guerriero ◽

Adolfo Dannier ◽

Santolo Daliento ◽

Davide Lauria ◽

...

Keyword(s):

Control System ◽

Control Method ◽

Fault Tolerant ◽

Storage System ◽

Energy Resource ◽

Energy Storage System ◽

Correct Operation ◽

Battery Packs ◽

Battery Energy ◽

The Hilbert Transform

The paper deals with design and control of a fault tolerant and reconfigurable photovoltaic converter integrating a Battery Energy Storage System as a standby backup energy resource. When a failure occurs, an appropriate control method makes the energy conversion system capable of operating in open-delta configuration in parallel with the grid as well as in islanded mode. In case network voltage is lacking due to heavy anomalies or maintenance reasons, the proposed control system is able to quickly disconnect the inverter from the grid while ensuring the energy continuity to the local load and the emergency fixtures by means of the integrated battery packs. In particular, the paper proposes a fast islanding detection method essential for the correct operation of the control system. This specific technique is based on the Hilbert transform of the voltage of the point of common coupling, and it identifies the utility lack in a period of time equal to half a grid cycle in the best case (i.e., 10 ms), thus resulting in good speed performance fully meeting the standard requirements. A thorough numerical investigation is carried out with reference to a representative case study in order to demonstrate the feasibility and the effectiveness of the proposed control strategy.

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MPPT Control Method of PV Based on subregional variable duty cycle

Proceedings of the 4th International Conference on Mechatronics, Materials, Chemistry and Computer Engineering 2015 ◽

10.2991/icmmcce-15.2015.300 ◽

2015 ◽

Author(s):

Bing Li ◽

Li Jun Zhong ◽

Gang Wang ◽

Xiaojian Tian

Keyword(s):

Duty Cycle ◽

Control Method

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Add-On Type Pulse Charger for Quick Charging Li-Ion Batteries

Electronics ◽

10.3390/electronics9020227 ◽

2020 ◽

Vol 9 (2) ◽

pp. 227 ◽

Cited By ~ 1

Author(s):

Bongwoo Kwak ◽

Myungbok Kim ◽

Jonghoon Kim

Keyword(s):

Lithium Ion Battery ◽

Lithium Ion ◽

Current Method ◽

Constant Current ◽

Experimental Conditions ◽

Battery Charging ◽

Long Run ◽

Pulse Charging ◽

Pulse Charge ◽

Battery Packs

In this paper, an add-on type pulse charger is proposed to shorten the charging time of a lithium ion battery. To evaluate the performance of the proposed pulse charge method, an add-on type pulse charger prototype is designed and implemented. Pulse charging is applied to 18650 cylindrical lithium ion battery packs with 10 series and 2 parallel structures. The proposed pulse charger is controlled by pulse duty, frequency and magnitude. Various experimental conditions are applied to optimize the charging parameters of the pulse charging technique. Battery charging data are analyzed according to the current magnitude and duty at 500 Hz and 1000 Hz and 2000 Hz frequency conditions. The proposed system is similar to the charging speed of the constant current method under new battery conditions. However, it was confirmed that as the battery performance is degraded, the charging speed due to pulse charging increases. Thus, in applications where battery charging/discharging occurs frequently, the proposed pulse charger has the advantage of fast charging in the long run over conventional constant current (CC) chargers.

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Improved Performance of Li-ion Polymer Batteries Through Improved Pulse Charging Algorithm

Applied Sciences ◽

10.3390/app10030895 ◽

2020 ◽

Vol 10 (3) ◽

pp. 895 ◽

Cited By ~ 3

Author(s):

Judy M. Amanor-Boadu ◽

Anthony Guiseppi-Elie

Keyword(s):

Duty Cycle ◽

Electronic Device ◽

Lithium Ion ◽

Cycle Life ◽

Constant Current ◽

Battery Charge ◽

Charge Current ◽

Pulse Charging ◽

Pulse Charge ◽

Improved Performance

Pulse charging of lithium-ion polymer batteries (LiPo), when properly implemented, offers increased battery charge and energy efficiencies and improved safety for electronic device consumers. Investigations of the combined impact of pulse charge duty cycle and frequency of the pulse charge current on the performance of lithium-ion polymer (LiPo) batteries used the Taguchi orthogonal arrays (OA) to identify optimal and robust pulse charging parameters that maximize battery charge and energy efficiencies while decreasing charge time. These were confirmed by direct comparison with the commonly applied benchmark constant current-constant voltage (CC–CV) charging method. The operation of a pulse charger using identified optimal parameters resulted in charge time reduction by 49% and increased charge and energy efficiencies of 2% and 12% respectively. Furthermore, when pulse charge current factors, such as frequency and duty cycle were considered, it was found that the duty cycle of the pulse charge current had the most impact on the cycle life of the LiPo battery and that the cycle life could be increased by as much as 100 cycles. Finally, the charging temperature was found to have the most statistically significant impact on the temporarily evolving LiPo battery impedance, a measure of its degradation.

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Control of Dual-Output DC/DC Converters Using Duty Cycle and Frequency

World Electric Vehicle Journal ◽

10.3390/wevj11040072 ◽

2020 ◽

Vol 11 (4) ◽

pp. 72

Author(s):

Yoshinori Matsushita ◽

Toshihiko Noguchi ◽

Kazuki Shimizu ◽

Noritaka Taguchi ◽

Makoto Ishii

Keyword(s):

Power Systems ◽

Duty Cycle ◽

Control Method ◽

Frequency Control ◽

Maximum Efficiency ◽

Control Factors ◽

Series Resonant ◽

Bridge Rectifier ◽

Bridge Circuits ◽

Resonant Filters

As part of the integration process of the auxiliary power systems of electric vehicles, plug-in hybrid vehicles and fuel cell vehicles, this study proposes a method to control two different voltage types using two control factors of the rectangular alternating waveforms contained in DC/DC converters, namely the duty cycle and frequency. A prototype circuit consisting of an H-bridge inverter, a transformer, two series resonant filters and two diode bridge circuits was constructed. The H-bridge inverter was connected to the primary side of the transformer and the diode bridge rectifier circuit was connected to the secondary side in parallel. Series resonant filters were inserted between one of the diode bridge circuits and the transformer. Thereafter, the proposed control method was applied to the transformer voltage of the prototype circuit. Although the circuit operation became complex owing to the circulating current flowing between the ground (GND) of the two output circuits, it exhibited ideal static and dynamic characteristics, thereby confirming the possibility of controlling two voltages with the duty cycle and frequency control factors. The results of the efficiency evaluation and loss analysis demonstrated a minimum efficiency of 68.3% and a maximum efficiency of 88.9%. As the output power of the circuit containing the resonant filters increased, the current peak value increased and the circuit became less efficient.

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