SMART GRID Smart Grid is one of a number of names used to describe a transmission and distribution network that uses modern sensing, computational, and communication technologies to improve the reliable and economic functioning of the bulk power system. Other names include Modern Grid, Intelli grid, and Future Grid. A
Year: 2014
There are a large range of possible approaches and concepts for storing energy in electric utility systems. These are discussed in the following subsections. 1) MECHANICAL SYSTEMS HYDRO PUMPED STORAGE: In hydro pumped storage, water is pumped from a lower to a higher elevation. The water at the higher elevation can
Energy storage applications offer potential benefits to the transmission and distribution system because of the ability of modern power electronics, and some electro-chemistries, to change from full discharge to full charge, or vice versa, extremely rapidly. These characteristics enable energy storage to be considered as a means of improving transmission
An alternate means of transmitting electricity is to use high-voltage direct current (HVDC) technology. As the name implies, HVDC uses direct current to transmit power. Direct current facilities are connected to HVAC systems by means of rectifiers, which convert alternating current to direct current, and inverters, which convert direct current
There are a number of designs used for substations. However, there are elements common to all: >> A BUS: is the physical structure to which all lines and transformers are connected. Buses are of two generic types: open air and enclosed. Enclosed buses are used when substations are located in
Substations are locations where transmission lines, transformers, and generators are connected. They fulfill a number of functions: Allow power from different generating stations to be fed into the main transmission corridors. Provide a terminus for interconnections with other systems. Provide a location where transformers can be connected to feed power
The primary components of an overhead transmission line are: Conductors Ground or shield wires Insulators Support structures Land or right-of-way (R-O-W) 1) CONDUCTORS: are the wires through which the electricity passes. Transmission wires are usually of the aluminum conductor steel reinforced (ACSR) type, made of stranded aluminum woven around a
Disturbances may also change the voltage at the generator’s terminals. In response, the generator’s automatic voltage regulating system will sense the change and adjust the generator’s field excitation, either up or down, to compensate. Transient stability or instability considers that period immediately after a disturbance, usually before the generator’s governor
YAW CONTROL The yaw control continuously orients the rotor in the direction of the wind. It can be as simple as the tail vane, or more complex on modern towers. Theoretical considerations dictate free yaw as much as possible. However, rotating blades with large moments of inertia produce high gyroscopic
Transformers are susceptible to damage by secondary short-circuit currents having magnitudes that can be many times rated load current. The damage results from the following effects: >> The I2R losses in the winding conductors are increased by the square of the current. This increases the temperature rise of the windings. >> Because protective
