One-Cycle Controlled Reactive Power Supply Inverter (OCC-RPSI) for Distributed Energy

Reactive power is both a problem and a necessity for the electric grid. Loads on the electric grid such as AC electric motors need reactive power to function and this requires the electric grid to deliver the reactive power. Reactive power occupies valuable capacity on the electric grid and can prevent loads from sourcing adequate real power, leading to brown-outs and black-outs such as the New York blackout on August 14, 2003. By enabling distributed energy resources (DER) like fuel cells, reciprocating engine generators, etc. to provide real and reactive power closer to the loads that require it, the operating margin of the electric grid and therefore its stability, reliability, and efficiency can be substantially improved. This project will develop a controller for commercial distributed energy (DE) inverters that enables DER to deliver both real and reactive power. The controller is based on technology that delivers a new paradigm: active conversion of 3­phase power without software. The technology enables a ten-fold reduction in circuit complexity and the elimination of control software to provide a substantial boost in system reliability and performance, necessary for large-scale deployment on DER. The Phase I project demonstrated a prototype able to rapidly deliver real and reactive power to the grid for voltage support without software. The Phase II project will develop a prototype that leverages the controller from Phase I to commercial size. The resulting controller product will interface with existing commercial DE inverters to accelerate market adoption. A streamlined subset of tests will be developed that facilitates regulatory approval for manufacturers who adopt the controllers for their end-user products. Commercial Applications and other Benefits as described by the awardee: The controller has commercial applications on fuel cells, micro-turbines, and reciprocating engine generators. The primary benefits are high-quality power, high reliability (due to low component count and no software), and reactive power injection/absorption when needed to support the grid.