901 articles
Curtailment (renewable energy)
Curtailment is the deliberate reduction of wind or solar power plant output when the grid cannot absorb the electricity, due to transmission limits, stability needs, or supply-demand imbalances.
Data logger (electric power)
A data logger for electric power is an instrument that automatically records quantities such as voltage, current, power, and energy for hours to months, without an operator present.
Datang Huayin Electric Power
Datang Huayin Electric Power is a Chinese power generation company based in Hunan province and controlled by China Datang Corporation, operating 8.5 GW of capacity, mostly coal.
DC circuit breaker
A DC circuit breaker is a switching device that interrupts direct current in DC power systems; unlike AC breakers, it must create a current zero artificially and dissipate stored energy.
DC connector
A DC connector, also called a DC plug, is an electrical connector for direct current, from power adapters to 1,500 V photovoltaic strings and EV charging.
Dead-end clamp
A dead-end clamp, also called a strain or tension clamp, is overhead line hardware that terminates a conductor and carries its full tension into a pole or tower.
Delhi Transco
Delhi Transco Limited, also known as DTL, is the Delhi government's state transmission utility, formed on 1 July 2002 from the unbundled Delhi Vidyut Board, operating Delhi's extra-high-voltage grid.
Delmarva Power & Light
Delmarva Power & Light Company is an Exelon-owned utility based in Wilmington, Delaware, serving about 532,000 electric customers on the Delmarva Peninsula and 136,000 gas customers in northern Delaware.
Demand response
Demand response is the reduction or shift in electricity consumption by customers in response to price signals, incentive payments, or grid reliability needs, helping balance supply and demand.
Dennis A. Woodford
Dennis A. Woodford is a Canadian power systems engineer from Winnipeg, Manitoba, who created the EMTDC/PSCAD simulation software, co-founded Electranix Corporation, and was elected to the US National Academy of Engineering in 2017.
Differential protection
Differential protection is a unit-protection technique in electrical power engineering that compares currents entering and leaving a zone, such as a transformer or busbar, and trips when the difference exceeds a threshold.
Directional overcurrent relay
A directional overcurrent relay, ANSI device 67, combines overcurrent and directional elements so it trips only for fault current above pickup flowing in a preset direction.
Distance relay
A distance relay is a protective relay, designated ANSI device 21, that measures voltage-to-current ratio to detect and locate faults within a set electrical distance of a power line.
Distributed generation
Distributed generation, also known as distributed or decentralized energy, is the production of electricity at or near the point of use, including rooftop solar and small wind.
Distribution automation
Distribution automation is the use of sensors, communications, and automated switching on the electric distribution grid to detect, isolate, and restore faults, reducing outage duration and extent.
Distribution board
A distribution board, also known as a breaker panel or fuse box, is an enclosure dividing an electrical supply into separate circuits protected by fuses or circuit-breakers.
Distribution company (India)
A distribution company in India, commonly called a DISCOM, is a licensed utility that purchases power and sells it to end consumers through the distribution network.
Distribution system state estimation
Distribution system state estimation (DSSE) is a power systems method that infers voltage magnitudes and angles across a distribution feeder from limited real-time and pseudo-measurements.
Distribution transformer
A distribution transformer, also called a pole pig or service transformer, makes the final step in voltage reduction, converting medium grid voltage to the low voltage used by homes and businesses.
DLMS/COSEM
DLMS/COSEM (IEC 62056) is an international standard suite for smart energy metering, combining the DLMS application layer and the COSEM object model, standardized since 2002.
Dominion Energy South Carolina
Dominion Energy South Carolina, the former South Carolina Electric & Gas, serves about 1.3 million customers in South Carolina and became a Dominion Energy subsidiary when SCANA merged in 2019.
Dorsey Converter Station
Dorsey Converter Station is an HVDC converter station in Rosser, Manitoba, where electricity from northern Nelson River hydro stations is converted back to AC, carrying over 70% of Manitoba's power.
Droop control
Droop control is a decentralized control method in which parallel-connected inverters and generators share active and reactive power from local measurements alone, with no communication links, making it the most implemented approach for islanded microgrids.
Dry-type transformer
A dry-type transformer is a power or distribution transformer insulated and cooled by air and solid materials like epoxy resin instead of oil, favored indoors for fire safety.
DTE Electric
DTE Electric is an investor-owned electric utility serving roughly 2.3 million customers in southeastern Michigan, including Detroit and Ann Arbor, as a subsidiary of DTE Energy.
Dubai Electricity and Water Authority
Dubai Electricity and Water Authority (DEWA; Arabic: هيئة كهرباء ومياه دبي) is the government-owned utility that is Dubai's exclusive provider of electricity and water, created in 1992.
Duke Energy Carolinas
Duke Energy Carolinas, a subsidiary of Duke Energy headquartered in Charlotte, North Carolina, is a regulated utility serving about 2.3 million customers in the central and western Carolinas.
Duke Energy Florida
Duke Energy Florida is a regulated electric utility serving roughly 2 million customers in central and west central Florida, with roots as Florida Power Corporation from 1899.
Duke Energy Indiana
Duke Energy Indiana is a regulated electric utility based in Plainfield, Indiana, serving about 860,000 customers across 23,000 square miles and owned by Duke Energy Corporation.
Duke Energy Kentucky
Duke Energy Kentucky, formerly the Union Light, Heat and Power Company, is a regulated utility serving about 152,000 electric and 105,000 gas customers in Northern Kentucky.