Study of Renewable Energy Integration into Traditional Grid Using Simplified Models of Wind and Pv Generators Forming Microgrid

Abstract:

As the conventional sources of energy like coal, natural gas, petroleum, and nuclear fuel are being exhausted at a rapid pace we feel the need to shift to alternatives. The idea of integration of renewable energy systems into grid or individual microgrids being connected to main grid also comes from the need for sustainable loading of the conventional thermal/gas based system.A Smart Mini-Grid has greater resilience to loading as compared to the conventional grid system. It is marked by power flow through multiple routes, a feature common to the conventional grid system. However, unlike the conventional grid system, it is designed to avoid cascade tripping of network elements.

In our project the miniature model of renewable energy based power system consists of critical and non-critical loads. A conventionaltransmission grid is simulated at one end. Multiple wind generators and a solar sources constantly charges a battery, to maintain a constant voltage, forming an Integrated System of Distributed Energy Resource (DER) as microgrid which is also connected to the main grid. The load is initially shared by both the renewable and conventional sources. However,theycan be fully supplied by either of the sources making each source independent. In case of faults on any one of the systems, a relay-circuit breaker mechanism isolates the required supply portion, while the full load is shared among the other sources connected to grid. Also in cases of less power availability or inconsistency in demand-supply ratio the critical loads like hospitals, offices are prioritized and the supply to household and other low priority areas are discontinued considering them as non-critical loads for some time till the optimum power is available.

Motivation:

A Smart Mini-Grid (SMG) is an intelligent electricity distribution network comprising of variable loads, operating at or below 11 KV, where the energy demand is effectively and intelligently managed by diverse range of Distributed Energy Resources (DERs) such as solar PV, micro-hydro power plants, wind turbines, biomass, etc. in combination with each other through smart control techniques.It not only provides effective inter-connection but also helps in advancing access to energy to the last mile in the most optimum manner by improving the efficiency of the overall system

It is been estimated that by 2020 or 2030 the whole world will be at a huge conventional source crisis, thus it is necessary to use modern utilities to overcome the variability and uncertainty of renewable generation and provide smooth integration into grid in a large scale basis to save the conventional resources.

As of 31 March 2011 the installed capacity of wind power in India was 16078 MW (fully onshore). it has the 5th largest wind power with potential estimated upto 48500 M.W.

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