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Grid connected inverter less hybrid energy conversion system
1P.Manikandan, 2A.Krishnaveni,3V.Vengatesh, 4S.Velmurugan, 5N.Pathmanaban
1Head of the Department, Department Electrical and Electronics Engineering, Sree Sowdambika College of Engineering, Aruppukottai, India.
2Communication System Engineer, AP Engineering works, Aruppukottai.
3, 4, 5 BE-IV Year Students, Department of Electrical and Electronics Engineering, Sree Sowdambika College of
Engineering, Aruppukottai, India.
Abstract – In this research work wind and solar hybrid system are used to produce the power. The generated power was given to the load. PIC microcontroller gets the supply from renewable energy and grid. PIC was used to monitor the generated power supply and controls relay to provide the supply to load. DPDT relay provides the adequate supply to the load. LCD displays the generated voltage and type of power supply. Here the inverter and Battery was not needed which will reduce the overall cost of the installation. The objectives of this research are to improve the efficiency hybrid system and to reduce the Harmonics related power quality problems.
Keyword: PIC, LCD, Relay, wind mill, solar panel
I. INTRODUCTION
1. Wind Energy System
Wind power was extracted from air flow using wind turbines or sails to produce mechanical or electrical power. Figure 1 shows the structure of wind turbine.
Figure 1 Wind Turbine Structure
Windmills were used for their mechanical power, wind pumps for water pumping, and sails to propel ships.
Wind energy as an alternative to fossil fuels, was plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land. The effects on the environment are generally less problematic than those from other power sources.
1.1 Wind Turbines 1.1.1 Large Turbines
Able to deliver electricity at lower cost than smaller turbines, because foundation costs, planning costs, etc.
are independent of size. Well-suited for offshore wind plants.
In areas where it is difficult to find sites, one large turbine on a tall tower uses the wind extremely efficiently.
1.1.2 Small Turbines:
Local electrical grids may not be able to handle the large electrical output from a large turbine, so smaller turbines may be more suitable. High costs for foundations for large turbines may not be economical in some areas.
1.1.3 Wind Turbines: Number of Blades
Most common design is the three-bladed turbine. The most important reason is the stability of the turbine. A rotor with an odd number of rotor blades (and at least three blades) can be considered to be similar to a disc when calculating the dynamic properties of the machine.
A rotor with an even number of blades will give stability problems for a machine with a stiff structure. The reason is that at the very moment when the uppermost blade bends backwards, because it gets the maximum power from the wind, the lowermost blade passes into the wind shade in front of the tower.
1.1.4. Wind Turbine Generators:
Wind power generators convert wind energy (mechanical energy) to electrical energy. The generator is attached at one end to the wind turbine, which provides the mechanical energy. At the other end, the generator is connected to the electrical grid. The generator needs to have a cooling system to make sure there is no overheating.
1.1.5 Small Generators
Require less force to turn than larger ones, but give much lower power output.
Less efficient
1.1.6 Large Generators
Very efficient at high wind speeds, but unable to turn at low wind speeds. Figure 2 shows schematic diagram of horizontal and vertical axis turbine.
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Figure 2 Horizontal and Vertical axis wind turbine 1.1.7 Advantages of Wind Power
The wind blows day and night, which allows windmills to produce electricity throughout the day. (Faster during the day)
Energy output from a wind turbine will vary as the wind varies, although the most rapid variations will to some extent be compensated for by the inertia of the wind turbine rotor.
Wind energy is a domestic, renewable source of energy that generates no pollution and has little environmental impact. Up to 95 percent of land used for wind farms can also be used for other profitable activities including ranching, farming and forestry.
The decreasing cost of wind power and the growing interest in renewable energy sources should ensure that wind power will become a viable energy source in the United States and worldwide.
II. SOLAR POWER SYSTEM
Solar power was the conversion of sunlight into electricity, either directly using photo voltaic (PV), or indirectly using concentrated solar power (CSP).
Concentrated solar power systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. Photovoltaic convert light into electric current using the photovoltaic effect.
Photovoltaic were initially, and still are, used to power small and medium-sized applications, from the calculator powered by a single solar cell to off-grid homes powered by a photovoltaic array.
2.1 General Information of Photovoltaic Systems Photovoltaic systems are designed to perform the following functions:
Convert solar energy to direct current electrical energy.
Regulate the electrical energy output.
Feed the electrical energy into an external load circuit to perform work or Store the electrical energy in a battery subsystem for later use.
Photovoltaic systems are designed for many applications varying in size and complexity. Some are isolated from ac power lines. Remote systems include navigational
aids along coastlines; beacons on mountain peaks, remote homes, and isolated villages in developing countries. Some photovoltaic systems have ac power or fossil fuel generators as a source of auxiliary electric power. Systems are designed for water pumping stations, for supplying power to TV and communication equipment, village power, auxiliary power for heating and cooling private homes and industrial applications.
A Standalone SPV system is the one which is not connected to the power grid. Standalone PV systems usually have a provision for energy storage. This system has battery support to supply the load requirements during the night hours or even when sunshine is not adequate (Cloudy conditions) during the day. Figure 3 shows the stand alone PV system.
Figure 3 Stand alone PV system 2.3 Charge Controller:
The charge controller regulates the flow of electricity from the PV modules to the battery and the load. The controller keeps the battery fully charged without overcharging it. When the load is drawing power, the controller allows charge to flow from the modules into the battery, the load, or both. When the controller senses that the battery is fully charged, it stops the flow of charge from the modules. Many controllers will also sense when loads have taken too much electricity from batteries and will stop the flow until sufficient charge is restored to the batteries.
III. HYBRID SYSTEM
3.1 Need for Hybrid System
(i) Hybrid Solutions are powered by sun and wind, just in order to guarantee that the power is enough to be charged in the solar battery every day.
(ii) If some day there is sunlight but without the wind energy, the solar panel charge the battery.
(iii) The other way round, if some day there is wind energy but without the sunlight, the wind turbine can charge the power to the battery.
(iv) When someday both wind & solar energy is enough, both can charge the battery.
(v) When the night is coming, the wind turbine is also can continue to work for supply the power to the system, so we sure the system will be popular in the coming future.
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(vi) We have standard hybrid systems available to meet power needs. Hybrid systems makes ideal for stand-alone operation.
(vii) Electronic controllers manage the multiple power sources and monitor the status of the batteries.
(viii) If the reserve runs low, the controller automatically starts the generator to supply power and charge the battery.
Figure 4 shows the Hybrid Solar power systems.
Figure 4 Hybrid Solar power systems Figure 5 shows the Wind Solar Hybrid systems.
Figure 5 Wind Solar Hybrid systems II. Proposed work
In this work wind and solar hybrid system are used to produce the power. PIC was used to monitor the generated power supply and controls relay to provide the supply to load. Here the inverter and Battery was not needed with the system, which will reduce the harmonics problem produced by the inverter.
III. Modeling of hybrid System 3.1 Hardware requirement:
PIC16F877A Microcontroller Solar Panel
Wind power generator LCD Display
Relay Driver
Software requirement:
Proteus software
3.2 Liquid Crystal Display (LCD)
LCD was a type of display used in digital watches and many portable computers. LCD displays utilize to sheets of polarizing material with a liquid crystal solution
between them. An electric current passed through the liquid causes the crystals to align so that light cannot pass through them. LCD technology has advanced very rapidly since its initial inception over a decade ago for use in lap top computers. Technical achievements has resulted in brighter displace, higher resolutions, reduce response times and cheaper manufacturing process.
Figure 6 shows the circuit diagram consists of PIC16F877A with relay and grid circuit.
Figure 6 Block diagram Figure 7 shows the circuit diagram
Figure 7 Circuit diagram IV. Experimental
Proteus (PROcessor for TExt Easy to USe) was a fully functional, procedural programming language created in 1998 by Simone Zanella. Proteus incorporates many functions derived from several other languages: C, BASIC, Assembly, Clipper /dBase; it is especially versatile in dealing with strings, having hundreds of dedicated functions; this makes it one of the richest languages for text manipulation. Proteus owes its name to a Greek god of the sea (Proteus), who took care of
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Neptune's crowd and gave responses; he was renowned for being able to transform himself, assuming different shapes. Transforming data from one form to another is the main usage of this language.
In this research work Proteus software were used to analyze the circuit performance. Figure 8 shows the Proteus software diagram.
Figure 8 Proteus software diagram
The following Figure 9 shows the complete hardware setup consists of solar panel and wind mill produce the power. PIC controls the process and provides required output voltage to the load. LCD provides the measurement of generated voltage. The experimental setup process was verified.
Figure 9 hardware setup
V. CONCLUSION
The performance of hybrid system connected with grid supply was analyzed by using Proteus software and hardware. The microcontroller with the relay circuit provides the required voltage to the load. In this research work, Inverter and batteries was not needed, which increases the performance of the system and reduces the initial and maintenance cost and reduces the harmonics developed by the inverter circuit.
VI. ACKNOWLEDGEMENT
Thank God and His almighty power to finish His research work by using me and my Project Guide my friend for His ultimate work.
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