Page 19 - Industrial Power Engineering and Applications Handbook

xvi Introduction
Part 111 Voltage surges, overvoltages distribution networks which are overloaded and which
and grounding practices present these problems.
In this part the author provides all relevant aspects of
(including causes, effects and remedies and a reactive control and carries out an exhaustive analysis
theory of overvoltages, ground fault protection of a system for the most appropriate control. Harmonic
schemes and grounding practices) effects and inductive interferences as well as use of filter
and blocking circuits are covered. Capacitor switching
This part is complementary to Part I1 and provides currents and surges and methods of dealing with these
technical support to switchgear assemblies and machines are also described.
fed by them for surge and overvoltage protection. It is a This part considers reactive power control with the
very useful part for all those handling HV and EHV use of shunt and series capacitors. The controls may be
power systems and their surge and overvoltage protection. manual or automatic through electromagnetic or static
devices. Protection of capacitors and capacitor banks as
The part deals with the BIL of a system, protective well as design, manufacturing and test requirements,
margins and insulation coordination. installation and maintenance are also covered, the main
It also deals with electric motors as they are typical thrust being on the application of power capacitors.
for their surge behaviour and protection.
It also covers the steepness of TRVs, their significance Application of series capacitors and analysis of an
and methods of taming them. Reflections of travelling uncompensated transmission line and the capability
waves and surge transferences are also described. of power transfer and system regulation with and without
This part specifically considers the application and series compensation are also presented.
selection of surge capacitors and surge arresters. Since To clarify the subject the basics and the behaviour of
the internal causes of surge generation are a consequence power capacitors in operation are also discussed.
of switching and type of interrupter, the part provides This part also briefly describes different types of power
details of the various types of interrupters in use, their reactors required to control inrush currents or suppress
switching behaviour, current chopping and quenching the system’s harmonic disorders, besides absorbing
of arc plasma. It also makes a detailed comparison of the excessive charging currents on an EHV system.
the various types of interrupters available to facilitate
their selection and adaptation to a more appropriate
surge protection scheme.
Temporary overvoltages are different from surges as Part V Bus systems in including
are their causes. Therefore temporary overvoltages also metal-enclosed non-isolated and
form an important parameter in a system design and isolated phase bus systems
its grounding method. This topic is therefore comple-
mentary to surge protection and has been dealt in detail Power transfer is a very important area of a power system.
to make a practising engineer or engineering student In this part it is dealt with in detail for both LT and HT
more aware of the behaviour of an HT system,
particularly on a ground fault. systems and for all current ratings. For large to very
large ratings, skin and proximity effects are also discussed
Exposure of a human body to touch and step voltages to arrive at a design to transfer large amounts of power,
and methods to deal with these are also covered. without great loss, voltage drop or voltage unbalance.
Grounding and ground fault protection schemes are Technical data and current ratings for various sizes and
described in detail with illustrations to help an engineer sections of aluminium are provided with more emphasis
to select the most appropriate grounding method and on aluminium as it is most commonly used. The text
ground fault protection scheme for a machine or system.
The use of CBCTs is covered. provides material to design, engineer, manufacture and
test a bus system of any current and voltage rating.
This part specifically deals with
Part IV Power capacitors: power
factor improvement and system Design parameters
voltage regulation: application of Short-circuit effects
Electrodynamic and electromagnetic forces
shunt and series capacitors Effects of proximity and reducing this by phase
interleaving or phase transposition
Reactive control is an important tool for voltage regulation Designing a reactor for the middle phase to balance a
and for optimizing available power utilization. It can large unbalanced current-carrying system
also be used for attaining better stability of the system. Recommended practices to mount buses and make bus
It has therefore become a very important technique to connections
improve an old distribution network that is being A detailed discussion of the isolated phase bus system
overutilized and is ailing with recurring problems such concentrating on types of isolated enclosures and their
as flickering of voltage, frequent system outages and a design aspects
normally low voltage at the consumer end. The author Sample calculation to design an IPB
has attempted to apply reactive control to improve power Testing of bus systems.