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Über dieses Buch

An important part of any communication system is its power supply system. The smooth operation of all communications depends on the quality of the power supply and on the operational reliability of the increasingly complex equipment and devices used for this purpose.
This book describes current power supply technologies, it explains the circuit techniques using easy-to-understand examples and illustrations. Also covered are automatic control, grounding and protection techniques as well as the design of battery and grounding installations.
The book is conceived as a practical guide for those involved in planning installing, comissioning and servicing telecommunication systems, but it is also useful as an introduction to the subject.

Inhaltsverzeichnis

Frontmatter

1. General and Introduction

Abstract
Most telecommunications systems operate from a d.c. supply voltage. This voltage has to meet specific requirements with regard to voltage tolerance and AF/RF ripple. The public a.c. mains voltage must be converted to d.c. by rectifiers which are equipped with electronic regulators. This enables the rectifiers to supply the necessary stabilized voltage independently of variations in a.c. mains voltage and frequency as well as of varying load demands. Built-in filters ensure that the d.c. voltage is smoothed to meet specifications.
Hans Gumhalter

2. Requirements of Telecommunications Systems on the Power Supply

Abstract
Table 2.1 contains the data on power supplies which are important in connection with the features of communications systems. Line 1 of Table 2.1 shows the rated voltages for communications systems. A distinction is made between 24, 48 and 60 V systems. Modern systems are usually 48 or 60 V, the positive pole normally being earthed. The choice of voltages also depends on the safety regulations of the country in question. In Germany, direct voltages over 120 V and alternating voltages over 50 V are classed as ‘dangerous contact voltages’.
Hans Gumhalter

3. Operating Modes of a Direct Current Power Supply System

Abstract
Figure 3.1 gives an overview of the operating modes of d.c. power supply systems currently in application. Table 2.1 applies to the operating voltages of communications systems.
Hans Gumhalter

4. Operating Modes of an Alternating Current Power Supply System

Abstract
The operating modes used for a.c. loads in communications systems are listed in Table 4.1.
Hans Gumhalter

5. Public Mains

Abstract
It is important to know the characteristics of the public power supply system (distribution network) when operating telecommunications power supply systems. This chapter explains the factors to be considered and the line-side conditions for which the equipment is designed.
Hans Gumhalter

6. Energy Storage

Abstract
An introduction to battery systems was presented in Section 1.4.
Hans Gumhalter

7. Basic Circuits and Process Control

Abstract
With the half-wave rectifier (Fig. 7.1) only the positive half-waves of an alternating current are passed. This circuit is suitable for low output powers. More complex filtering is necessary to suppress interference voltages.
Hans Gumhalter

8. Applications of Control Systems in Power Supply Devices

Abstract
This chapter treats the application of control engineering in modern power supply equipment in more detail. Some elementary correlations and terms in open-loop control and closed-loop control are presented for those readers for whom this part of the subject is not so familiar.
Hans Gumhalter

9. Switching Mode Power Supplies

Abstract
At this point a selection of equipment will be described; they all employ the principle of pulse-width control.
Hans Gumhalter

10. Thyristor Controlled Rectifiers

Abstract
At this point a selection of equipment will be described; they all employ the principle of phase-angle control.
Hans Gumhalter

11. Magnetically Controlled Rectifiers

Abstract
Magnetically controlled rectifiers have been used in power supply systems for more than 40 years.
Hans Gumhalter

12. D.C./D.C. Converter

Abstract
D.C./D.C. converters are designed either as single-height or double-height power supply units or as complete built in equipment; they all deliver constant controlled (component) supply voltages.
Hans Gumhalter

13. D.C./A.C. Inverters

Abstract
At this point a selection of equipment will be described.
Hans Gumhalter

14. Static UPS Systems

Abstract
At this point the introduction and basic circuits of static UPS systems (as in Sects. 1.7, 4.3 and 4.3.5) are recalled. A selection of the equipment will be described in Fig. 14.1. Different examples of types, series and power ranges of UPS-systems are listed in Table 14.1.
Hans Gumhalter

15. Diesel Generating Sets

Abstract
An introduction to standby power supply systems (diesel generating sets) was presented in Sect. 4.2.1.
Hans Gumhalter

16. Special Features for Transmission System Power Supplies

Abstract
In considering power supplies for long-range transmission systems it is necessary to distinguish between the following:
  • power supply systems in telecommunication towers,
  • power supply systems in ground communications stations and
  • power supply systems independent of mains supplies.
Hans Gumhalter

17. Grounding and Potential Equalization

Abstract
Grounding (earthing) embraces all the means and methods whereby conducting parts are connected to earth through a grounding system.
Hans Gumhalter

18. Protective Measures

Abstract
To avoid accidents from electrical causes, the rules for the prevention of accidents of the professional association1, the VDE regulations (e.g. DIN 57 100/VDE 0100) and all other safety rules should be observed.
Hans Gumhalter

Backmatter

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