Research On Key Techniques Of Hybrid (PV-Wind) Nano Grid For Rural Electrification

The world grapples with the challenges of increasing energy demand for a large and growing population,which is substantially dependent on fossil fuel imports.The second largest global issue is that of climate change.Numerous countries gathered in Paris in 2016 to seek an agreement that addresses climate change.Many countries across Africa,the Asia Pacific region,Latin America,the Caribbean,and the Middle East have suffered a succession of severe energy crises due to inadequate development on the supply side,which has crippled their economic growth.The majority of countries are eager to devise policies,plans,and programmes that include affordable,clean and sustainable energy supply-based renewable energies.Researchers are focusing on many renewable energies and applications,especially in the field of hydro,solar,wind,bio and geothermal to fulfill the development vision of a country to match current demand.Solar and wind renewable energy are rapidly developing to fulfill the energy gap.This increasing share of renewable energy is a reaction to the ecological trepidations to conciliate economics with security due to new challenges in power system supply.To support rural areas in developing countries,a unique hybrid(PV-Wind)nanogrid is designed which can generate dual energy from a single platform with primary and secondary energy for a single household.To support higher communal loads,it can support without large and dedicated distributed generation.The planned architecture is composed of several hybrid nanogrids that are proficient in self-sustained generation and storage with the ability to support the bidirectional power flow within the microgrid.The distributed voltage droop control and bidirectional power flow are implemented via duty cycle control of an improved Flyback converter.A comprehensive study regarding system efficiency,losses,and power flow are presented using the Newton-Raphson technique altered for the DC power flow at capricious conductor sizes with the distribution voltages and different interconnection structures between the causative hybrid nanogrids.The proposed architecture is scaled down with various power-sharing scenarios and implemented on hardware.The balancing aspect of power between demand and generation in electrical networks is difficult with an increase in distributed energy resources(DERs),especially for the uncertainty of renewable generation.Smart grid concepts have been developed to solve this problem.A set of distributed generation in terms of households and community based is developed based on demand flexibility and energy storage devices which are locally managed to minimize the local total generation cost.However,the impact of energy storage on the micro-grid has not been explored.In this thesis,a local smart market based on a multi-agent system is presented to provide for the quantitative evidence of the beneficial impact of flexibility,which is enabled by demand flexibility and energy storage in limiting market power by distributed generation household units.A quantitative analysis is proposed by a bilevel optimization model in a micro-grid setting,which accounts for the operational constraints of energy storage.This bi-level problem is solved after converting it into a Mathematical Program with Equilibrium Constraints(MPEC)and linearizing the latter using suitable techniques.In solar and wind renewable energy,the only partial predictable is the output with very low controllability,which creates unit commitment problems in generating units.In this thesis,a different linear formulation via mixed integers is presented;this formulation proposes the requirement of ‘binary variables' and restraints concerning previously mentioned models.The framework of this model precisely considers the cost of time-dependent start-ups and intertemporal limitations,for example,minimum up and down times and a ramping limit.To efficiently solve the unit commitment problem,commercially available mixed integer linear programming is applied on a sizeable practical scale.This thesis has highlighted key issues in worldwide to support the prerequisites for sustainable,equitable and social-economic development.The findings will strengthen developing countries in pursuit of renewable energy solutions for a sustainable energy future.