The objective of the CERTS Microgrid Test Bed Demonstration with American Electric Power was to enhance the ease of integrating small energy sources into a microgrid. The project accomplished this objective by developing and demonstrating three advanced techniques, collectively referred to as the CERTS Microgrid concept, that significantly reduce the level of custom field engineering needed to operate microgrids consisting of small generating sources.
The techniques comprising the CERTS Microgrid concept are: (1) a method for effecting automatic and seamless transitions between grid-connected and islanded modes of operation; (2) an approach to electrical protection within the microgrid that does not depend on high fault currents; and (3) a method for microgrid control that achieves voltage and frequency stability under islanded conditions without requiring high-speed communications.
The techniques were demonstrated at a full-scale test bed built near Columbus, Ohio and operated by American Electric Power. Other participants in the CERTS Microgrid Test Bed Demonstration included University of Wisconsin-Madison (PSERC), Sandia National Laboratories, Woodward, Princeton Power Systems, Northern Power Systems, Tecogen, and Lawrence Berkeley National Laboratory. This demonstration was sponsored by the California Energy Commission PIER Electric Transmission Research Program.
The testing fully confirmed earlier research that had been conducted initially through analytical simulations, then through laboratory emulations, and finally through factory acceptance testing of individual microgrid components. The islanding and re-sychronization method met all Institute of Electrical and Electronics Engineers 1547 and power quality requirements. The electrical protection system was able to distinguish between normal and faulted operation. The controls were found to be robust under all conditions, including difficult motor starts.