The Grid CoRe (Correction and Regulation) series of products, developed by the Electrical Distribution Division, are designed specifically to meet the utility challenges of distributed generation, two-way power flow, variable volage optimisation and conservation voltage reduction (CVR).
At the heart of each Grid CoRe unit is an advanced three-phase static synchronous compensator (STATCOM). This uses Mitsubishi Electric's insulated gate bipolar transistor (IGBT) modules and modular multilevel converter architecture to provides sub-cycle voltage optimisation combined with additional grid support features including voltage phase balancing and harmonic mitigation. It combines the functions of conventional equipment such as reactors, shunt capacitors and load tap changers in a single unit for a more stable grid and improved recovery after a transient event.
“Mvar-sized FACTS devices are required to support grid stability at the transmission level. By moving into the primary distribution network, Mitsubishi Electric’s Grid CoRe can have a significant impact on MVA-sized feeders with kvar-sized devices,” said Kevin Goldstein, engineering and development manager for the Electrical Distribution Division of Mitsubishi Electric Power Products..
The decentralised architecure provides up to 2,000 kvar of reactive power in building blocks of 500 kvar units. Supporting the primary distribution grid up to 46kV, this allows the utility to target a specific localized grid issue. “By strategically applying Grid CoRe units, utilities can dynamically change the active voltage profile along an entire feeder, by requiring up to 20 percent less total kvar than a centralized solution,” said Goldstein. “By applying advanced Grid CoRe technology, our customers can avoid costly reconductoring and remedy voltage violations within their distribution system.”