Controller Area Network Assisted Grid Synchronization of a Microgrid With Renewable Energy Sources and Storage

Abstract : Microgrids are emerging as an important constituent of large-scale smart grids. They are equipped with the controls necessary for managing the operation in islanded or grid connected mode and serve the loads with clean, reliable, and uninterruptible power. Microgrid must be equipped with a robust grid synchronization (GS) algorithm so as to allow a smooth transfer from islanded mode to grid tied mode. This gets even more critical when the availability of the power grid is irregular or the power grid is weak. This paper proposes a simple yet highly reliable GS technique based on controller area network (CAN) communication. The grid synchronizer block senses the three phase grid voltages, derives the phase angle (?) using synchronously rotating reference frame-based phase lock loop, and transmits this information on the CAN network to all microsources (MS). The local controller associated with each MS receives the data with small but known and definite time latencies. This allows each MS to energize simultaneously in synchronization with the grid, facilitating easy GS of all the MS, minimizing the time required for GS of the complete microgrid. All the analytical, simulation, and hardware results related to this paper are presented.

 EXISTING SYSTEM :

 ? There exists so many forecasting tools for wind and solar power generation, still the power generation from these RESs is said to be unpredictable as weather conditions are uncertain in nature. ? The advent of smart grid technologies in power sector has brought so many changes in existing techniques and algorithms that are used for grid micro grid synchronization. ? The PLC is having its best advantage as it uses the existing power line as the medium and hence it is a preferable choice for cost effective communication. ? There are many existing challenges, the majors are: charging/discharging balance, safety, reliability, size, lifecycle, cost, in addition to the overall control and management.

 DISADVANTAGE :

 ? The intermittent nature of these creates problems in the distribution network. ? Most of the problems like frequency variations, protection and optimal energy management will take care by main grid in parallel mode of operation. ? Apart from energy demand crises, the globe is now facing a big problem with greenhouse gases releasing from power generation and transportation. ? DSL are another level of quality communication as the data is transferred in digital form with no disturbance, whereas the PLC is facing problems with interference.

 PROPOSED SYSTEM :

 • This paper presents a comprehensive review of decentralized, centralized, multiagent, and intelligent control strategies that have been proposed to control and manage distributed energy storage. • In particular, the strategy has proposed a high pass filter-based droop (HPFD) for battery converter, and a virtual capacitance droop (VCD) controller to control the supercapacitor (SC). • The role of the heterogeneous energy storage system here is to retain DC bus voltage under the control of the new proposed strategy. • The proposed controller has considered an SOC balance and charging constraints.

 ADVANTAGE :

 ? The concept of integrating heterogeneous entities helps in improving grid efficiency, demand side management (flat load profile) and economic benefits. ? These smart grid entities makes the micro grid more efficient in terms of all aspects: energy sharing among DGs, adaptive protection, V and f control and smart way of island detection. ? ICT provides adequate real time data with negligible latencies in data transfer which makes the EMS more efficient in taking decisions for load/generator shedding or scheduling. ? EMS through ESS control will be a better choice for efficient management of micro grid.