* Grid Interconnection and Islanding Operations
Expert-defined terms from the Postgraduate Certificate in Sustainable Microgrid Management course at HealthCareStudies (An LSPM brand). Free to read, free to share, paired with a globally recognised certification pathway.
**Active Power #
** The component of electric power that performs work, typically measured in watts (W). In a sinusoidal AC system, the active power can be calculated as the product of the voltage, current, and power factor.
**Active Power Control #
** A feature of microgrids that enables the real-time management of active power flow to maintain the stability and reliability of the grid. This is typically achieved through the use of energy storage systems, generators, and advanced control algorithms.
**Air #
Gap Isolation:** A type of electrical isolation that uses a physical gap between two circuits to prevent the flow of electrical current. This is often used in microgrids to isolate the AC and DC sides of the system.
** Alternating Current (AC) #
** An electrical current that changes direction periodically, typically measured in hertz (Hz). AC is the most common type of electrical power used in modern grids.
**Battery Energy Storage System (BESS) #
** A system that stores electrical energy in a battery for later use. BESSs are commonly used in microgrids to provide energy storage and support active power control.
**Circuit Breaker #
** An electrical switch designed to protect a circuit from damage due to overcurrent or short-circuit conditions. Circuit breakers are an essential component of microgrids, as they provide a means of isolating faulty circuits and preventing damage to the system.
**DC Microgrid #
** A type of microgrid that uses direct current (DC) as the primary means of electrical power transmission. DC microgrids are often used in remote or off-grid locations, as they can be easier to implement and maintain than AC microgrids.
**Decentralized Energy Resources (DERs) #
** Small-scale, distributed energy resources, such as solar panels, wind turbines, and fuel cells, that are connected to the grid at the distribution level. DERs are often used in microgrids to provide a diverse mix of energy sources.
**Dielectric #
** A material that is used to insulate electrical conductors and prevent the flow of electrical current. Dielectrics are an essential component of microgrids, as they provide electrical isolation and help to prevent accidents and equipment failure.
**Distributed Generation (DG) #
** The generation of electrical power at the distribution level, typically through the use of decentralized energy resources (DERs). DG is a key component of microgrids, as it allows for the integration of renewable energy sources and the reduction of transmission losses.
**Electrical Isolation #
** The separation of electrical circuits to prevent the flow of electrical current. Electrical isolation is an important safety feature of microgrids, as it helps to prevent accidents and equipment failure.
**Emergency Power Supply (EPS) #
** A backup power system that is designed to provide electrical power during an emergency or power outage. EPSs are often used in microgrids to ensure the continued operation of critical loads during a blackout.
**Fault Current #
** An abnormal current that flows in an electrical circuit due to a short-circuit or other fault condition. Fault currents can be significantly higher than normal operating currents and can cause damage to electrical equipment if not properly managed.
**Frequency Control #
** The management of the frequency of an electrical power system to maintain the stability and reliability of the grid. Frequency control is an important aspect of microgrid operations, as it helps to ensure the smooth transition between grid-connected and islanded modes.
**Grid #
Connected Mode:** A mode of microgrid operation in which the microgrid is connected to the main electrical grid. In this mode, the microgrid can import or export power to the grid as needed.
**Grid #
Forming Inverter:** A type of inverter that is designed to form and maintain the grid voltage and frequency. Grid-forming inverters are an essential component of microgrids, as they provide the necessary control and stability functions to ensure the reliable operation of the system.
**Grid #
Tied Inverter:** A type of inverter that is designed to convert DC power from a renewable energy source, such as solar panels, into AC power that can be fed into the grid. Grid-tied inverters are a key component of microgrids, as they allow for the integration of renewable energy sources into the grid.
**Harvesting Control #
** The management of the power extraction from decentralized energy resources (DERs) in a microgrid. Harvesting control is an important aspect of microgrid operations, as it helps to ensure the efficient and reliable operation of the system.
**Inverter #
** An electronic device that converts DC power into AC power. Inverters are a key component of microgrids, as they allow for the conversion of DC power from renewable energy sources into AC power that can be used by electrical loads.
**Islanded Mode #
** A mode of microgrid operation in which the microgrid is disconnected from the main electrical grid and operates as a standalone system. In this mode, the microgrid must be able to maintain its own voltage and frequency stability.
**Load Balancing #
** The management of the power flow between different electrical loads in a microgrid. Load balancing is an important aspect of microgrid operations, as it helps to ensure the efficient and reliable operation of the system.
**Microgrid #
** A small-scale electrical power system that is designed to operate autonomously or in conjunction with the main electrical grid. Microgrids typically consist of a mix of decentralized energy resources (DERs), energy storage systems, and advanced control and management systems.
**Microgrid Control System (MCS) #
** A system that is used to manage and control the operation of a microgrid. The MCS is responsible for monitoring the status of the microgrid, managing power flow, and ensuring the stability and reliability of the system.
**Passive Power #
** The component of electrical power that does not perform work, typically measured in volt-amperes reactive (VARs). In a sinusoidal AC system, the passive power can be calculated as the product of the voltage, current, and reactive power factor.
**Photovoltaic (PV) System #
** A system that converts sunlight into electrical power. PV systems are a common type of decentralized energy resource (DER) used in microgrids.
**Power Conditioning System (PCS) #
** A system that is used to convert and condition electrical power for use in a microgrid. The PCS is responsible for managing the power flow between different electrical loads and sources, and for ensuring the stability and reliability of the system.
**Power Electronics Converter (PEC) #
** A device that is used to convert and control electrical power in a microgrid. PECs are often used in conjunction with decentralized energy resources (DERs) to manage the power flow and ensure the stable operation of the system.
**Power Factor #
** The ratio of the real power (active power) to the apparent power (the product of the voltage, current, and the square root of one minus the power factor squared) in an AC system. A power factor of one indicates that the system is operating at maximum efficiency.
**Reactive Power #
** The component of electrical power that is stored and released in the electric and magnetic fields of an AC system. Reactive power is measured in volt-amperes reactive (VARs) and is not directly consumed by electrical loads.
**Renewable Energy Source (RES) #
** A source of electrical power that is derived from renewable resources, such as sunlight, wind, or hydropower. RESs are often used in microgrids to provide a diverse mix of energy sources and to reduce the reliance on fossil fuels.
**Resonant Converter #
** A type of power electronics converter that is designed to operate at a specific resonant frequency. Resonant converters are often used in microgrids to provide high-efficiency power conversion and to reduce the size and weight of the power electronics components.
**Ride Through #
** The ability of a microgrid to continue operating during a temporary disturbance or fault in the electrical power system. Ride through is an important feature of microgrids, as it helps to ensure the continued operation of critical loads during a blackout.
**Single #
Phase System:** An electrical power system that uses a single phase to transmit electrical power. Single-phase systems are commonly used in residential and small commercial applications.
**Stability Control #
** The management of the voltage and frequency stability of an electrical power system. Stability control is an important aspect of microgrid operations, as it helps to ensure the reliable and efficient operation of the system.
**Three #
Phase System:** An electrical power system that uses three phases to transmit electrical power. Three-phase systems are commonly used in industrial and commercial applications, as they provide a more stable and efficient power supply than single-phase systems.
**Transient Control #
** The management of the short-term dynamic behavior of an electrical power system. Transient control is an important aspect of microgrid operations, as it helps to ensure the stable and reliable operation of the system during rapid changes in power demand or supply.