A comprehensive control strategy for Wind Solar powered autonomous AC DC Hybrid Micrigrid with Battery Energy Storage

Abstract

Countries across the globe are moving towards higher levels of renewable energy (RE) integration so as to reduce the amount of greenhouse gas emission. Some countries have set ambitious target of 100% RE penetration. When the microgrid is 100% RE and autonomous, it should meet its demand by itself, i.e. any new power demand in AC network or DC network newlineshould be met by the local generation and storage. Additionally, with large penetration of RE sources involving converter fed powers, microgrid controllers must achieve the dual task of newlinecommanding the local current, voltage and power control at the converter level, besides coordinating the overall network power balancing and energy management. newlineA simultaneous multiple control is developed, which is presented in this thesis, to achieve simultaneous control actions at multiple locations so as to maintain power balance in the microgrid under a wide range of operating conditions. Voltage regulations in AC and DC networks and power exchange between the two networks have been accomplished through newlineDC-DC and AC-DC converters employed in the system. Wind-driven DFIG in standalone mode regulates AC network voltage and frequency by use of a feedforward-infused-feedback control, called Dynamic Frequency Tracking, on the- rotor side for better dynamic response. The wind turbine as well as PV is operated with Maximum Power Point Tracker as long as their powers are absorbed in the designated load or battery and operated off these points otherwise. Deferrable loads are included to bring operational flexibility to meet the excess generation in the microgrid.Five power electronic converters are used in the system to implement this control strategy. Simultaneous multiple control uses system-monitored real time operational parameters like newlineSoC, rotor speed, power exchanges and voltages, which are shared among various local controllers avoiding the need of central controller. The results validated the effectiveness of the simultaneous multiple control scheme that takes..