Funding Program: SuNLaMP
SunShot Subprogram: Systems Integration
Location: National Renewable Energy Laboratory, Golden, CO
SunShot Award Amount: $3,849,999

Adding large amounts of photovoltaic (PV) solar energy onto the grid creates significant challenges for future grid operations, since the electric power grid currently operates with rotational inertia from fossil fuel-driven machines. However, PV inverters are power-electronic devices with no inherent inertia. This project will develop a suite of inverter controllers to ensure the long-term viability of electric power grid infrastructure and address the large reductions in system-wide inertia with high penetrations of PV. These grid-forming inverter controllers will allow each inverter to act as a controllable voltage source that dynamically adjusts its output to ensure system-level stability, synchronization, and voltage regulation.

Approach

The project team will design and implement digital controls for power electronic inverters to emulate the dynamics of a nonlinear oscillator. With the proposed strategy in place, the intrinsic electrical coupling between inverters will promote system-wide synchronization. A key component of this approach is to ensure backwards compatibility by incorporating drop-in replacement interoperability with existing inverters. This will facilitate a gradual evolution of the power grid to a network driven by inverters and help ease industry adoption.

Innovation

A comprehensive commercialization strategy will be designed and implemented to translate the finalized grid-forming controllers into sets of open-source reference designs that contain bills of materials, schematics, printed circuit board layout source files, and control codes. The open-source nature of the product will ensure that interested consumers and manufacturers can easily download complete reference designs and implement them with minimal development time.