Types of Electrical Grids
– Microgrid: a local grid that can operate autonomously and use distributed generators
– Wide area synchronous grid: directly connects generators and consumers, facilitating electricity market trading
– Super grid: a wide-area transmission network that enables the trade of high volumes of electricity across great distances
– National Grid: the network in the United Kingdom, India, Tanzania, Myanmar, Malaysia, and New Zealand
– Off-grid systems: provide electricity to areas not connected to a main grid
Components of the Electrical Grid
– Generation: process of generating electric power from sources of primary energy
– Transmission: bulk movement of electrical energy from a generating site to an electrical substation
– Substations: transform voltage from low to high (step up) and from high to low (step down)
– Electric power distribution: carries electricity from the transmission system to individual consumers
– Storage: used for large-scale energy storage within an electrical power grid
Voltage in the Electrical Grid
– Grids supply electricity at constant voltages
– Voltage adjustments are made using tap changers on transformers
– Grids deal with varying demand, reactive loads, and nonlinear loads
– Generators in a synchronous grid must run at the same frequency
– Capacity and firm capacity of a grid
Operation and Management of the Electrical Grid
– Load sharing based on marginal cost and environmental impact
– Handling failures and addressing transmission bottlenecks
– Brownouts, blackouts, and load shedding
– Black start procedures for restoring power without relying on the external grid
– Demand response as a grid management technique
Challenges and Issues in the Electrical Grid
– Aging infrastructure leading to higher failure rates and costs
– Obsolete system layouts and outdated engineering tools
– Cultural values and deregulation impacting the industry
– Distributed generation and its impact on the grid
– Grid resilience and reliability in the face of challenges Source: https://en.wikipedia.org/wiki/Electrical_grid
An electrical grid (or electricity network) is an interconnected network for electricity delivery from producers to consumers. Electrical grids consist of power stations (often located near source of energy and away from heavily populated areas), electrical substations to step voltage up or down, electric power transmission to carry power long distances, and lastly electric power distribution to individual customers, where voltage is stepped down again to the required service voltage(s). Electrical grids vary in size and can cover whole countries or continents. From small to large there are microgrids, wide area synchronous grids, and super grids.
Grids are nearly always synchronous, meaning all distribution areas operate with three phase alternating current (AC) frequencies synchronized (so that voltage swings occur at almost the same time). This allows transmission of AC power throughout the area, connecting a large number of electricity generators and consumers and potentially enabling more efficient electricity markets and redundant generation.
The combined transmission and distribution network is part of electricity delivery, known as the "power grid" in North America, or just "the grid." In the United Kingdom, India, Tanzania, Myanmar, Malaysia and New Zealand, the network is known as the National Grid.
Although electrical grids are widespread, as of 2016[update], 1.4 billion people worldwide were not connected to an electricity grid. As electrification increases, the number of people with access to grid electricity is growing. About 840 million people (mostly in Africa), which is ca. 11% of the World's population, had no access to grid electricity in 2017, down from 1.2 billion in 2010.
Electrical grids can be prone to malicious intrusion or attack; thus, there is a need for electric grid security. Also as electric grids modernize and introduce computer technology, cyber threats start to become a security risk. Particular concerns relate to the more complex computer systems needed to manage grids.
