Inaustrial Power Engineering and Applications Handbook I K.C. Agra Wal QiB Newnes [...]... overvoltages and grounding practices (including causes, effects and remedies and theory of overvoltages, ground fault protection schemes and grounding practices) This part is complementary to Part I1 and provides technical support to switchgear assemblies and machines fed by them for surge and overvoltage protection It is a very useful part for all those handling HV and EHV power systems and their surge and. .. hand rule Figure 1.4 Production of magnetic field in a 3 4 winding 1/6 industrial Power Engineering and Applications Handbook where 4 = &,sin ut and Q, = maximum field strength ,, In a 3-4 winding, therefore, for the same amount of current, the torque developed is 50% more than in a 2-4 winding The rotor power P developed by torque T a t a speed N can be expressed by p = -T N 974 where P = rotor power. .. output and torque and results in a higher slip and rotor loss This subject is covered in more detail in Section I2.2(v) For likely deratings, refer to Figure 12.1.A system with an unbalance of up to 1 % or so calls for no derating, whereas one having an unbalance of more than 5% is not recommended for an industrial application, because of a 1/10 Industrial Power Engineering and Applications Handbook. .. even more useful and up to date K.C Agrawal Acknowledgements The author acknowledges with gratitude the help extended to hiin by his colleagues and friends and for the catalogues and leaflets from various manufacturers Also helpful have been a score of references and textbooks on the sub,jrct as well as product standards such as IEC, IEEE, ANSI and NEMA ISO, BS and IS and other national and international... saturation, raising the value of L It will provide a high dampening effect (RlL) initially and slowly thereafter The current will also decay rapidly initially and then slowly The same will be true for any inductive circuit other than a motor 1/8 Industrial Power Engineering and Applications Handbook 1.4 Motor ratings and frame sizes 1.2.2 Rotor current With the same parameters, the rotor current of a motor,... manufacturing and test requirements, installation and maintenance are also covered, the main thrust being on the application of power capacitors Application of series capacitors and analysis of an uncompensated transmission line and the capability of power transfer and system regulation with and without series compensation are also presented To clarify the subject the basics and the behaviour of power capacitors... In (and and a larger circle diameter, due to higher I,, 120 112 5 t TPO 107 5 I1O s 100 ,4 t2 0 F -0 + 90 8 80 70 s =1 Speed- +Slip s SI z s 2 'S I Figure 1.7 Higher full-load slip at lower voltages * 95 105 % Apphed voltage + 0 Motors are designed to develop rated output at 95% voltage Figure 1.9 Effect of voltage variation on the motor output 1/12 Industrial Power Engineering and Applications Handbook. .. illustrating hysteresis loss 1/14 Industrial Power Engineering and Applications Handbook on this, a designer can take corrective action to minimize these losses For all practical purposes, the core losses may be regarded as proportional to the square of the flux density With a reduction in voltage, the flux 41 and so the flux density B will decrease in the same proportion as the voltage and so will the core losses... rocedure and effluent treatment is covered for those in the field of manufacturing such assemblies In an attempt to provide as much information on the related subjects as possible and to make the book more complete for a project or a design engineer we have provided data and tables on cables and described in detail the procedure for the selection of the type and size of control and LT and HT power cables... resistance method Perm issihle orrtpur % 1116 Industrial Power Engineering and Applications Handbook Effect of cooling water inlet temperature 100 For large motors, which use water as the secondary coolant in a closed circuit, the temperature o f the cooling air,i.e o f the primary coolant, varies with the temperature o f the cooling water inlet temperature and i t s rate o f flow For the performance . x0 y0 w2 ha" alt="" NEWNES POWER ENGINEERING SERIES Industrial Power Engineering and Applications Handbook NEWNES POWER ENGINEERING SERIES Series. 5073 7 NEWNES POWER ENGINEERING SERIES Industrial Power Engineering and Applications Handbook K.C. Agrawal Newnes BOSTON OXFORD AUCKLAND JOHANNESBURG