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Motoring protection is provided for the steam or hydraulic turbine, or for the power system, and not for the generator. Motoring is not harmful to the generator in any way. The protection is usually considered as part of the generator protective system since it uses electrical quantities, usually in the form of sensitive power relays. […]

It has been noted above that over-speed causes overvoltage, which may be protected against using overvoltage relays. Basically, however, over-speed control is part of the turbine control system. Most large steam turbine controls have two or three separate speed control units, with one of these being strictly a mechanical centrifugal device that will close the

It is astonishing to realize that there is hardly a home, office block, factory, car, sports hall, hospital or theatre without an application, and sometimes many applications, of power electronic equipment. Some typical applications are given below: Industrial processes in the chemical, paper and steel industries; Domestic and theatre lighting; Motor drives from food mixers and

Having decided the voltage that are required to be created at any substation it is necessary to establish a common insulation level for all items of equipment of each system voltage. It is to be ensured that the breakdown or flashover strength of all insulation (particular voltage) in the station will exceed the selected level.

RELIABILITY Is the overall objective in power system design and operation. To be reliable, the power system must be secure most of the time. To be secure, the system must be stable but must also be secure against other contingencies that would not be classified as stability problems e.g., damage to equipment such as an

The growing number of power electronics base equipment has produced an important impact on the quality of electric power supply. Both high power industrial loads and domestic loads cause harmonics in the network voltages. At the same time, much of the equipment causing the disturbances is quite sensitive to deviations from the ideal sinusoidal line

The electrical powers generated are either transferred onto a bus to be distributed (small scale), or into a power grid for transmission purposes (larger scale). This is done either directly or through power transformers, depending on the generated voltage and the required voltage of the bus or power grid. The next step is power transmission,

VAR compensation is defined as the management of reactive power to improve the performance of ac power systems; maximizing stability by increasing flow of active power. Few Problems forced while reactive power compensation which are: 1. Load compensation 2. Voltage support LOAD COMPENSATION OBJECTIVES: are to increase the value of the system power factor to

SVC: Uses thyristor valves to rapidly add or remove shunt connected reactors and or capacitors often in coordination with mechanically controlled reactors and/or capacitors. NGH-SSR DAMPER: a resonance damper, a thyristor ac-switch connected in series with a small inductor and resistor across the series capacitor. STATCOM (static condenser): A 3 phase inverter that is driven

Flexible transmission system is akin to high voltage dc and related thyristors developed designed to overcome the limitations of the present mechanically controlled ac power transmission system.  Use of high speed power electronics controllers, gives 5 opportunities for increased efficiency. Greater control of power so that it flows in the prescribed transmission routes.  Secure loading