Microgrid Controls

A microgrid can be defined as a self-contained, self-supporting area that has its own generation resources with the ability to separate from an external grid for sustainability or energy surety purposes. Depending on the specific requirements of a large site or distribution area, there may be numerous advantages to developing a microgrid, including:

• To reduce the duration of grid disruptions through distributed energy resource (DER) management and self-healing functionality
• To achieve a net power balance to enable autonomous operation
• To increase efficiency; microgrids require minimal generation and transmission
• To ensure energy surety; microgrids are self-sustainable

BlueFin™ Microgrid Control Strategy

The BlueFin™ microgrid control strategy has been refined through strategic project activities in collaboration with Energinet.dk, the Transmission Service Operator in Denmark, for the Cell Controller Pilot Project. This project used software similar to the present BlueFin™ controller. 

The BlueFin™ microgrid control uses several optimization techniques to minimize energy consumption while maintaining the reliability of the islanded microgrid. Some specific features of the BlueFin™ microgrid controller are found below:

• BlueFin™ maximizes the renewable energy contribution as long as system reliability can be maintained within defined limits
• Generators are operated in their most efficient ranges, with sufficient spinning reserves to accommodate for load fluctuations
• Storage (hydrogen or battery storage if available) allows diesel engines to run in their most efficient zones and to decrease the amount of spinning reserves required
• Ability to Island, in the event of a “hard” or unplanned island, BlueFin™ can be configured to maintain adequate spinning reserves at all times to avoid a blackout

BlueFin™ Islanding

As demonstrated in the Initial Cell Controller concept, BlueFin™ has the ability to enable sites, or portions of the distribution network, to operate autonomously from the transmission grid, or “island” upon receiving a signal from the network operator. This includes the ability to: ensure sites can rapidly shed load or generation to be approximately neutral, separate from the transmission grid, operate the site as an islanded power system within existing grid codes, the ability to bring generation online and restore loads, and upon receiving a signal from the distribution or transmission network operator, the ability to resynchronize with the grid. For more, please see the Case Study section on this page.

BlueFin™ Market-based Primary and Ancillary Power Services

BlueFin™ also enables sites and portions of distribution networks to use their distributed generation to deliver market-based primary and ancillary power services. With BlueFin™ controls, systems are able to respond to market-based requests for virtual generation (from power balancing authorities), voltage control or VAR support (from distribution and transmission network operators) and Import/Export control requests from the transmission network operator. For more, please see the Case Study section on this page.