Microgrids are viable option to the remote areas or far islands where extension of the main grid is either impossible or uneconomical. Microgrid are generally comprised of Distributed Energy Resources (DERs) with interconnected loads, storages and controllers. DERs may be renewable or nonrenewable energy sources. Renewable sources like solar and wind are uncertain sources providing intermittent power output. Energy storage systems such as batteries are used to increase the utilization of photovoltaic by storing excess energy for use when production is lower than demand. Another alternative is to supplement renewable sources with non-renewable sources of energy. However, it introduces additional costs for fuel and transportation. Batteries, therefore, are often beneficial to microgrids for maintaining reliability and power quality. A proper energy management algorithm with Controllable Area Network (CAN) can be used to control the operation of battery for the efficient operation of the microgrid.
A hybrid inverter/charger and battery management system in microgrid system can be controlled though CAN protocol. Control commands can be sent using CAN bus as physical layer of communication. CAN transmits data in terms of sequences and packages. It is an advanced differential two line serial communication network which supports real-time control. CAN was used as communication medium from central controller to hybrid inverter/charger in the microgrid testbed at Microgrid Research Laboratory in South Dakota State University, Brookings, SD. The charge and inverter modes of the hybrid inverter/charger were changed via CAN bus. Similarly, charge rate and maximum sell ampere were set and SOC of the battery was monitored through CAN bus.
- The control of hybrid inverter/charger via CAN bus is well suited and economical for commercial microgrids.
- CAN bus control of COTS inverter/charger is an economical design procedure replacing expensive custom power equipment in any microgrids.