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Rapidly growing cellular bandwidth demand has driven the deployment of smaller and smaller micro/nano cell wireless base-stations. Many of these deployments are in places that may be remote, hard-to-reach, environmentally uncontrolled, or near humans where noise and aesthetics may be important. As a result, new requirements have emerged: higher reliability, easier installation and repair in difficult...
The amount of energy consumed by data centers and telecom buildings is increasing annually due to the buildup and high-density arrangement of ICT equipment, which is needed to handle the rapid rise in traffic brought on by the spread of smartphones and advances in the Internet usage environment. The NTT Group, whose business activities are centered about ICT services, uses approximately 8.5 billion...
This paper presents a supercapacitor prediction aging model according to the voltage and to the temperature for telecommunication applications. To investigate this phenomenon, an experimental test bench is designed to accelerate the supercapacitors' calendar aging. Experimental tests are carried out at constant temperatures when the supercapacitors are polarized at the maximum voltage. To quantify...
Predicting the State-of-Health (SoH) of lead acid batteries in renewable energy field application is well known as a hard feasible task, due the fact that the operation condition is very shifty. This paper presents the design and real-time implementation of a SoH prediction based on artificial neural network model. An experimental setup was developed and presented here to indicate outperformance,...
This paper investigates into the key parameters (e.g. voltage, frequency, waveform, etc.) of HFAC Power Distribution Systems (PDS) ranging from smaller 0.5 kW laptop/desktop computer upto 1.0 MW domestic/commercial/industrial power distribution applications. Due to the high reactance and associated issues observed with increased frequency, different HFAC PDSs have been designed to operate with different...
State feedback decoupling permits to achieve a better dynamic response for Voltage Source in stand-alone applications. The design of current and voltage regulators is performed in the discrete-time domain since it provides better accuracy and allows direct pole placement. As the attainable bandwidth of the current loop is mainly limited by computational and PWM delays, a lead compensator structure...
Power converters requiring wide voltage and power ranges (including power factor correction converters) are difficult to effectively implement with soft switching at high frequencies, limiting their density and/or efficiency. We propose a soft-switched converter that can operate at HF (3–30MHz) across wide input voltage and power ranges. A prototype converter experimentally achieves zero voltage switching...
Energy storage systems (ESS) are broadly employed to smooth out the fluctuation in the PV output caused by cloud passing, or variability of solar irradiance with a high ramp rate. This paper compares the smoothing operation, and ramp rate control in two different architectures: cascaded and parallel topologies. Parallel architecture with reduced number of power switches, simpler controller, and as...
This paper presents the investigation of the effects of Silicon-Carbide Schottky Barrier Diodes (SiC SBDs) on the switching transient performance of a SiC MOSFETs-based Bidirectional Switching Power Pole (BSPP). The investigation was focused on the contribution of the SiC SBDs in reducing the overshoot in the drain current when they are connected as freewheeling diodes. A double pulse test (DPT) is...
As demand for data centers grows with the expansion of cloud computing and storage, so too does the power consumption. In the search for more efficient and reliable power delivery to the servers that make up the data centers, researchers and industry have been investigating various power delivery options. Recently, series-stacked architectures have been proposed to address the efficiency limitation...
In this paper, we studied the sensitivity of conversion efficiency in class-E resonant inverter under variable load assignment (resistive and inductive loads within rated range). By performing simulation and mathematical analysis, we found that the on-resistance of switching devices has minor effect on efficiency reduction and thus the assumptions in mathematical analysis are acceptable for preliminary...
The role of the equipment controller is changing in the Software-Defined Network (SDN). In the past, the role of the controller was focused on providing alarms and status information. In the Software-Defined Network, the controller provides the alarming and status with real-time information about the available capacity and historical information about energy use. With the larger role of equipment...
The use of cellular phones and hence its infrastructure has been growing very rapidly across the globe. The power system for a cell phone tower needs uninterrupted power supply. Hence its power system relies heavily on batteries and Diesel Generator (DG) sets — especially at those places that do not have a regular power grid. The batteries need heavy maintenance and do not work well at high temperatures...
The aim of this paper is to present a superior transient response of a digital peak current mode dc-dc converter in order to address input voltage fluctuation. In the dc power feeding system, a quick response is important for not only load fluctuation but also input voltage fluctuation. Since the proposed peak current mode control method can detect the peak current in real time, the transient response...
This work presents a crude bioethanol fueled integrated power system for backup and off-grid applications. The system is based on ethanol steam reformation to hydrogen that is used in polymer electrolyte fuel cells to produce electricity. We introduce the system design and overall system specifications, and report the experimental process of defining specifications for the produced hydrogen quality,...
Intelligent networking of stationary energy storage systems, electric vehicles, or uninterruptable power supply systems for data centers enables the integration of renewable and fluctuating power sources to higher extents. For economically operation of the increasing number of storage components it becomes essential to maintain unequally aged or deteriorate battery cells. Aged batteries from electric...
This paper presents modeling of communication systems dependency on electric power during nuclear attacks. Resiliency models are used to characterize cell site dependencies on the main power grid and transportation system for generator back up fuel. Primary failure due to direct damage and secondary failures due to dependencies versus yield are studied considering the effects of radiation, blast wave...
This paper presents experimental investigations on a real Orange telecommunication cabinet cooled using a special designed cooling loop in order to increase its maximum operating power limit and reduce its electrical consumption. The proposed cooling loop is an innovative development in the telecommunication cabinets cooling field since it operates without electrical consumption. Different condenser...
The basic characteristics of a 400 VDC appliance coupler for use in the power input module of ICT equipment in data centers and similar facilities are reported. When ICT equipment is powered at 400 VDC, the electrical characteristics differ from when conventional AC power is used and greater safety considerations are required. To maintain safety, the appliance coupler used in this evaluation is equipped...
Current sensing plays dominant role in power converters, where current information can be used for controlling, monitoring and protection. One of the most challenging goals in modern power electronics converters is to increase switching frequency for the purpose of miniaturization, and improve the performance especially for end-users. Therefore, the need for accurate, lossless, and fast response current...
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