Power Generation and Requirements
– Electrical generating plants require power for various operations.
– Different types of plants have specific power requirements.
– Normally, power is generated within the plant.
– In case of a wide-area outage, off-site power is not available.
Black Start Methods and Sequence
– Some power stations have on-site diesel generators for black start.
– These generators can start larger generators in the station.
– Black start can be performed in a specific sequence.
– A battery starts a small diesel generator in a hydroelectric station.
– The power from the diesel generator brings the station into operation.
– Key transmission lines are energized to restore connections.
– The power from the station starts other power plants in the system.
Procurement of Black Start Services
– In the UK, commercial agreements are in place for black start capacity.
– Power stations with open-cycle gas turbines can run the entire plant.
– In North America, black-start procurement varies.
– Integrated utilities traditionally provided black-start capability.
– In the US, there are three methods of procuring black start.
Different Methods of Commencing a Black Start
– Various methods can be used for black start, depending on factors such as cost and resources.
– Hydroelectric dams, diesel generators, and grid-scale battery stores are some methods.
– Different generating networks have different approaches.
– Factors like cost, complexity, and interconnectivity influence the method chosen.
– Response time is also a crucial factor in the black start process.
Limitations on Black Start Sources
– Not all generating plants are suitable for black-start capability.
– Wind turbines may not be available when needed for black start.
– Wind turbines, mini-hydro, or micro-hydro plants are often connected to induction generators that cannot provide power to re-energize the network.
– The 69MW Dersalloch wind farm black-started part of the Scotland grid in 2020 using virtual synchronous machines.
– Black-start units must be stable when operated with the large reactive load of a long transmission line. Source: https://en.wikipedia.org/wiki/Black_start
A black start is the process of restoring an electric power station or a part of an electric grid to operation without relying on the external electric power transmission network to recover from a total or partial shutdown.
Power to restart a generating station may come from an on-site standby generator. Alternatively, where a large amount of power is required, a tie-line to another generating plant may be used to start the facility. Once the main generating units are running, the electrical transmission network can be re-connected and electrical loads restored.
Black-start power may be ensured by an agreement where a particular energy supplier is paid to make black start power available when required. Not all generating plants are suitable for providing black-start power to a network.
