February 2015

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

A bus is a node at which one or many lines, one or many loads and generators are connected. In a power system each node or bus is associated with 4 quantities, such as magnitude of voltage, phage angle of voltage, active or true power and reactive power in load flow problem two out of

1) Power flow analysis is very important in planning stages of new networks or addition to existing ones like adding new generator sites, meeting increase load demand and locating new transmission sites. 2) The load flow solution gives the nodal voltages and phase angles and hence the power injection at all the buses and power

Transient stability is very much affected by the type of the fault. A three phase dead short circuit is the most severe fault; the fault severity decreasing with two phase fault and single line-to ground fault in that order. If the fault is farther from the generator the severity will be less than in the

The controlled rectifier circuit is divided into three main circuits, (1) POWER CIRCUIT This is the circuit contains voltage source, load and switches as diodes, thyristors or IGBTs. (2) CONTROL CIRCUIT This circuit is the circuit, which contains the logic of the firing of switches that may, contains amplifiers, logic gates and sensors. (3) TRIGGERING

DIAC (Diode for Alternating Current) is like a TRIAC without a gate terminal. DIAC conducts current in both directions depending on the voltage connected to its terminals. When the voltage between the two terminals greater than the breakdown voltage, the DIAC conducts and the current goes in the direction from the higher voltage point to the