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The free maintenance batteries used on telecommunicator applications belong to the very new models produced on that aim. Those are stationary lead acid batteries with grid type pasted. We have used alloys with a reduced content of stibium (less than 2 precentes) and an addition of Selenium (1.25%) in the producing process of the positive and negative grills of those batteries. The active mass was...
This paper presents the results of a prototype charger development, coupling a dual-level constant potential charger with a microprocessor controller. The controller implements a charging algorithm which exploits the inherent Ampere-Hour Rule of lead-acid batteries to prevent overcharge while guaranteeing rapid recharge, independent of the battery technology, battery age, battery capacity, discharge...
The high reliability of power systems utilizing paralleled rectifiers or converters is based on redundancy of individual modules. This paper traces the origines of the load-sharing approach to airborne electromechanical power systems and highlights the fundamental features of today's state-of-the-art approaches. The emphasis is on the over-all performance, reliability and user-friendliness.
Newly-improved Quasi-Resonant DC Link (QRDCL) three-phase voltage-sourced inverter circuit topology operating under a commutation principle of the high-frequency (HF) transformer-assisted Zero Voltage Switching (ZVS) is proposed. The basic operating principle of this power conversion circuit using Auxiliary Transformer-assisted QRDCL (TQRDCL) more suitable for CVCF/UPS, power active filter, switched-mode...
Extension of existing communication entities is often confronted with power supply problems relative to telecommunication equipment with different power supply requirements. several off-line power plants for a single entity are not reasonable in most cases. What are the ways to resolve the problem? This paper answers to this and some other questions. It presents compatibility analysis for power circuits...
A computer simulation technique for the synthesis and harmonic analysis of PWM waveforms is developed to investigate a wide range of operating modes using both time and frequency-domain analysis. The model can be combined with an electrical machine model to represent variable-speed drive systems or, alternatively, combined with a filter-load model and feedback control to simulate voltage regulating...
A high-perfomance ZVS-PWM three phase AC/DC active power converter using a newly proposed transformer-assisted Quasi-Resonant DC Link (TQRDCL) is described in this paper. The operating principle of this TQRDCL which has such excellent features as minimum dc bus voltage stress and no comlexity in predictive initializing resonant inductor current control under load fluctuations is discussed. A simple...
Integrated System Power, (ISP) is used for systems where power supplies and electronics are placed together in the same rack. The advantages and disadvantages of this kind of power system is discussed. A high power density ISP-system for radio base stations in a GSM-system, RBS 200, is described The system consists of digitally controlled rectifiers, DC distribution and batteries. The whole system...
The portable telecommunications market (cellular phones, etc) represents a major outlet for batteries in the next five years. The compactness, light weight, extended autonomy and low price required for mass market telephone sets are also needed for the batteries. To meet these demands, Saft is developing and manufacturing batteries with a range of different technologies (Nickel-Cadmium, Nickel- Metal...
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