Bimode uninterruptible power supply compatibility in renewable hybrid energy systems

An alternative to inverters with add-on charging circuits or standby uninterruptible power supply (UPS) hardware, the bimode UPS, is discussed. The bimode UPS uses common circuitry and power components for DC-to-AC inversion and battery charging. It also provides an automatic and nearly instantaneous AC power transfer function when the engine-generator is started or stopped. The components of the renewable hybrid energy system are described to provide a background for understanding the bimode evaluation. Operating characteristics and requirements of each part of the system are provided. A short description of standby UPS is given, and a comparison of the two systems is made to establish their similarities; the similarities show how the UPS may be used in hybrid systems. Evolution of the UPS to the bimode UPS allows simplification of the hybrid system if the bimode UPS proves its compatibility with loads, batteries, and engine generator. The renewable conversion device operates independently of the UPS. The incorporation of the bimode UPS is discussed, and the Abacus bimode UPS is evaluated.<>