Implementing an Electric Utility Microgrid: Lessons learned

In recent years, weather events, such as hurricanes, have caused prolonged power outages and significantly impacted the economy due to the damage to the electric utility infrastructure. To increase the resiliency of the electric power grid, microgrids started to become a preferred solution. Unlike traditional generation plants that consist of synchronous-based units, the majority of recently installed generation has been in the form of inverter-connected renewables (solar, wind, battery, etc.), resulting in significant operational challenges for the distribution system due to the intermittent nature of these distributed energy resources (DERs). Traditional electric utility systems effectively control field devices, such as capacitors and voltage regulators, which have delays associated with their operation. However, due to the traditional centralized architecture of electric power systems in general, effective real-time control of renewables is challenging due to the time it takes for changed field conditions to be identified within the centralized control system. In such cases, by the time the centralized system is ready to issue the operating command, the field operating conditions have changed. The issued operating command does not optimize the performance of the subject DER, which has led to work on localized control systems and operations. To provide localized control, secure local data access, interoperability, and distributed intelligence are key enabling factors for faster adoption of DERs and optimized control.