Part 1 Part 2 Part 3 Part 4 Part 5

Synopsis PART I

Electric Motors, Drives and Energy Saving

This part deals with three- and single-phase a.c. machines, and their protective switchgears. However, reference is made to and comparisons drawn of a d.c. motor with an a.c. motor, to assist a user make a proper choice of machine. Energy conservation, energy auditing and energy efficient motors (EEM). However simple a motor is, it requires careful handling to ensure optimum performance and long years of trouble free operation. A small drive, failing while in operation, may bring the entire process to a halt. One can visualize the loss of production that can result. Power plants, chemicals, fertilizers, petrochemicals, paper and cement mills all require careful selection of equipment to avoid breakdown or malfunctioning during operation. Motors and their control gears are core components that require special attention:

. It deals with the specifications, performance, characteristics and behavior of motors under different operating conditions, their application and selection. It also covers aspects such as shock loading, motors for hazardous locations and open transient conditions in MV motors during a switching sequence.

. This part-also deals with static controls and drives, soft starting and process control through solid-state technology (phasor and field-oriented controls) using IGBTs, IGCTs, SGCTs. Energy conservation. Developments and applications of solid state technology. Grounding practices and shielding of signals. Prevention from bearing currents.

. There is special coverage of fluid couplings for soft starting and speed control. A comparison between static drives and variable-speed fluid couplings is made.

. Windmills (induction generators) as an unconventional energy source, vertical hollow shaft motors and submersible pump sets, selection of energy efficient and space saver belts for transmission of load, the phenomenon and remedy of shaft currents.

. The text especially covers testing requirements and an introduction to quality assurance systems and application of ISO 9001(2000).

. Special coverage of impulse testing of resin-rich formed coils and their in-house testing requirements.

. In Chapter 12 a detailed analysis is made of all unfavorable operating conditions and their effect on the performance of the motor and its protection for optimum utilization.

The precautions also cover surge protection for MV motors. The details provided cover the smallest-influence that a particular parameter can have on the machine. Microprocessor based switching devices (IEDs) and intelligent starters.   


ebook electrical engineering