REWA ULTRA MEGA SOLAR POWER PLANT, REWA DISTRICT, MADHYA PRADESH, INDIA 🇮🇳🇮🇳

🌞⚡REWA ULTRA MEGA SOLAR POWER PLANT⚡🌞

⚡Rewa Ultra Mega Solar is the first solar project in the country to break the grid parity barrier. It is one of the largest solar power plant in India.It is an operational ground mounted, grid-connected Photovoltaic solar park spread over an area of 1,590 acres (6.4 km²) in the Gurh tehsil of Rewa district of Madhya Pradesh.The project was commissioned with 750 MW capacity in December 2019.Rewa Ultra Mega Solar Limited (RUMSL), the implementing agency of the project, is a joint venture between the Madhya Pradesh Urja Vikash Nigam Limited (MPUVNL) and the solar energy corporation of India (SECI). RUMSL was set up in July 2015 with Manu Srivastava, Principal Secretary, New & Renewable Energy, Government of Madhya Pradesh as its Chairperson, and he continued as its Chairperson till the completion of the project.

⚡For all solar parks in India, development of land and associated infrastructure are undertaken by state-led Solar Power Park Developer, while conceptualization, market consultations, financial and legal structuring and bid process management are activities undertaken by federal companies, viz., NTPC and SECI. RUMSL, though created only in July 2015, led at the State level and having Rewa as its first project, has the distinction of being the only entity in the country to have undertaken both these roles.

⚡While earlier projects by federal companies were awarded with target tariff of Rs.4.50/unit and the bidding was on Viability Gap Funding (VGF) to reach the target tariff, Rewa project went ahead without any VGF support and achieved a first year tariff of Rs. 2.97/unit. This has been the first project in India with rates of solar power below those of coal-based power, which is presently around Rs 4.50/unit and is expected to increase over the years.

⚡Rewa is the first project in India to be supplying power to an inter-state open access customer, viz., Delhi Metro. This is also the first project in India where solar power would be used for railway traction.

⚡The project got World Bank Group’s President’s Award for excellence for its transaction structure.

⚡The bidding for Rewa went on for 33 hours on February 9 and 10, 2017. Power Purchase Agreements and all other agreements of the project were signed on April 17, 2017 in Bhopal in the presence of Shivraj Singh Chouhan Chief Minister of Madhya Pradesh,Venkaih Naidu then Minister of Urban Development and Piyush Goyal then Union Minister of Power, Coal, Mines and New & Renewable Energy. The project was part commissioned on July 5, 2018. Supply to Delhi Metro commenced on April 18, 2019. The project was completed on January 3, 2020. The project was formally inaugurated on July 10, 2020 by the Prime Minister of India Narendra modi. 

⚡The Project secured a place in the book on innovations, ‘New Beginnings’ released by the Prime Minister of India Narendra modi, which is a publication of Department of Administrative Reforms & Public Grievances, GoI.

⚡Rewa Solar plant is India’s first solar project to get funding from clean technology fund (CTF) which is available at a rate of 0.25% for a 40-year period, and from the World Bank.This has enabled Rewa Project to have very low solar park charges, which was one of the contributing features behind the low tariff achieved in Rewa Project.

⚡Minister of State for Renewable Energy Piyush Goyal informed the Lok Sabha in July 2014 that the government intended to construct a 750 MW solar park in Rewa.

⚡PGCIL was awarded the contract for developing the 220/400 KV substation for the evacuation of power from the project site to different consumers. M/S Alstom was selected by PGCIL to develop the construction of substation work. Internal infrastructure for the project was developed by the RUMSL. RUMSL developed the project site which allowed developers to set up the unit without worrying about the evacuation infrastructure.

🌞AUCTIONS DONE ON REWA ULTRA MEGA SOLAR POWER PLANT 🌞

⚡RUMSL selected developers based on 3 stage assessment viz; Technical Proposal, Financial Proposal, Reverse Auction. RUMSL conducted the bid and reverse auction process using the Electronic Tender Portal hosted by the Telecommunication Consultants India Ltd (TCIL).

⚡The 750 MW capacity was auctioned in three packages of 250 MW each. RUMSL invited bids from solar power developers in January 2017. Twenty firms submitted bids, from which eighteen were shortlisted based on their financial and technical proposal to participate in the bidding process.The reverse auction process for the project involved 33 hours of non-stop bidding by the shortlisted bidders beginning at 10 AM on 9 February 2017. Mahindra susten, ACME Solar Holdings, and Solengeri Power won the first, second and third units quoting tariffs of Rs 2.979, Rs 2.970 and Rs 2.974 for the first year of operations. In Jan 2017, these were the lowest tariffs ever awarded through a bidding process for a solar project in India, however is now higher than the INR 2.44/unit quoted in the new auctions for the Bhadla solar park. International finance corporation was the transaction advisor of the project. The total cost of the project is estimated around ₹4,500 crore.

🌞Special Project Features:

• Perfect example of ‘plug & play’, and how it can bring down solar prices in India.
• Initiative by state rather than federal companies. Largest solar power tender led by a State and not led by CPSUs.
• Demonstrated that solar energy can become viable on commercial principles and does not need subsidy (Viability Gap Funding).
• First project in India supplying power to an inter-state open access customer.
• World Bank loan, as also from clean technology fund (CTF) for the development of 33/220 KV Pooling substations to evacuate power from the Rewa Solar power project.
• PGCIL developed the 220/400 kV Inter-state transmission system for Rewa Solar Power Plant to different power purchasers.
• First project to get funding from Clean Technology Fund (CTF) in India.
• Innovative design of Contracts to address the varying demand pattern of the off-takers.
• Three tier payment security Mechanism for the procurer – First time in India.
• Innovative Payment Security Fund (PSF) was developed along with Indian Renewable Energy Development Agency (IREDA), based on commercial principles rather than budgetary allocation.
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🌞ACCORDING TO THE ARTCILE PUBLISHED BY THE INDIAN EXPRESS ON 12 July 2020.🌞

🌞How does the Rewa Solar Power Plant match up to similar plants in India and abroad?

🌞The 750- megawatt Rewa solar Power Plant in Madhya Pradesh was dedicated to the nation by Prime Minister Narendra Modi on July 10. The plant consists of three solar power generating units that are located on a 500-hectare plot of land inside a 1,500-hectare solar park.

⚡The 750- megawatt Rewa solar Power Plant in Madhya Pradesh was dedicated to the nation by Prime Minister Narendra Modi on Friday (July 10). The solar plant was set up by the Rewa Ultra Mega Solar Limited, a joint venture between Madhya Pradesh Urja Vikas Nigam Limited and the Centre’s Solar Energy Corporation of India (SECI). The project has also received Rs 138 crore financial assistance from the central government.

⚡The plant consists of three solar power generating units that are located on a 500-hectare plot of land inside a 1,500-hectare solar park. Mahindra Renewables Pvt, Arinsun Clean Energy Pvt, and ACME Jaipur Solar Power Pvt are the three companies that bagged the mandate to build the three generating units, with a bulk of the equipment for it coming from China.

🌞Is it the largest solar plant in Asia?

⚡The 750-MW solar plant is quite large in terms of scale, and is expected to reduce the country’s emission drastically, by an amount equivalent to 15 lakh tonne of carbon dioxide annually. But while it is one of the largest single-site solar power plants in India, it is not the largest in Asia.

⚡The distinction of the world’s second largest photovoltaic power station goes to the Bhadla Solar Park, with a capacity of 2,245 MW, in Jodhpur district in Rajasthan, and the Pavagada Solar Park in Tumkur district, Karnataka, which has a capacity of 2,050 MW. According to data from Bloomberg New Energy Finance, there are nine solar plants that are bigger than the one at Rewa.

⚡Rewa Ultra Mega Solar is an operational solar park spread over an area of 1,590 acres (6.4 km2) in the Gurh tehsil of Rewa district of Madhya Pradesh. The project was commissioned with 750 MW capacity in July 2018

⚡Rewa Ultra Mega Solar Limited (RUMSL), the implementing agency of the project, is a joint venture between the Madhya Pradesh Urja Vikash Nigam Limited (MPUVNL) and the Solar Energy Corporation of India (SECI).

🌞Project Specific Points:

⚡Minimum tariff of the time for solar projects received from Rewa Solar Project: 2.97 per unit for first year (without Viability Gap Funding)

⚡Revenue land allotted for the project: 1255.68 hacteres. 

⚡Private land purchased under the ‘mutual consent policy’ of the state government: 300 hectares

⚡Amount received by the state as registration from developers: Rs 7.5 crore

🌞Other Project Points

1) Participation in transparent tender process by 20 international and national companies

2) Construction of 220/400 kV sub-station without the expense of state ROMS

3) Recognition of project contracts at the national level as a model by the Ministry of New and Renewable Energy, Government of India

4) Co, blockage of 15.4 lakh tonnes annually from the project, which is equivalent to planting 26 million trees

5) Rewa Solar Project named for Prime Minister’s “Book of Innovation”

6) Received “President Award” from World Bank for World Bank and the first project Transaction structure with CTF loan. 

🌞Why The Rewa Plant Is Critical To India's Solar Energy Ambitions? 

⚡On 15 February, 2015, Prime Minister Narendra Modi made an interesting observation in his inaugural speech for the first RE-Invest global summit in New Delhi. He remarked that Indian energy sector has been thinking in terms of Mega Watts (MW), but for the first time, India had started talking about Giga Watts (GW).

⚡It was inconceivable that India aimed at 100 GW of installed solar power capacity by 2022, given that the entire country had under 3 GW of existing installations when the Modi government took over. Yet, the ambitious target set clearly signalled the government’s intent to make solar energy an integral part of Indian energy security strategy.

ELECTRO-MAGNETIC RAIL GUN

⚔️ ELECTRO-MAGNETIC RAIL GUN⚔️

🗡️electromagnetic railgun use one of the weapon which uses electromagnetic force to launch the high velocity projectiles.  generally here no gun powder ua used.  gunpowder is generally used in Bullets in a small amount  that is because it is generally used more amount of gunpowder  in the bullets then the muskets may blow up.  As general you know that the Ganpur is generally used6 in the bullets and once the gun pistol of the gun is generally fired the bullies get burnt up and then the bullet will be released, creating a massive impact.  and as you know generally that only a small amount of gunpowder is used in the bullets and the gunpowder is very much difficult to handle since it cannot be exposed to the air.  we need to pay special attention during the handling of the gunpowder.  the compound which is used in the bullets only can travel up to a shorter distance or has some Limited range where are you be generally used the electromagnetic railgun here we are not making use of any gunpowder or any of the explosives powder and it generally depends upon the natural phenomena like electromagnetic force.  but there are also advantages and disadvantages in the electromagnetic railgun mechanism.  in electromagnetic railgun we generally require a large amount of supply current generally in order to operate the  electromagnetic railgun.  next we are going to discuss about the working operation of the electromagnetic railgun and we are also going to see that whether the electromagnetic railgun is available in India and whether we are using it in India or not.

 🗡️electromagnetic railgun they generally make use of the Electromagnet when the current will be general flew to the Electromagnet the magnetic field is generally generated.  and the magnetic field which will generally produce more amount of kinetic energy and this kinetic energy will fire the projectile with higher velocity and that is the main feature of the electromagnetic railgun.  as we know the bullet generally consists of different components like the primer the propellant like the gun powder and the bullet chase and the bullet.  we have discussed earlier about water generally the problems with the  gunpowder,  import originally used inside the bullet and if you general use a gunpowder inside the bullet it was generally make the bullet have little bit heavy with generally has a limit that we cannot the bullet cannot be Fire to the longer distance and also if the gunpowder is generally exposed to the air it will generally create a lot more problem like the  evaporation  takes place.  in order to avoid all these problems we are generally making use of a new technology called the electromagnetic railgun.

🗡️ the electromagnetic railgun as also outclass the Mach 7,  it was more than 7 times as it files with most compared to that of the Mach 7, and it also been proved that it generally had traveled of some 2050 kilometres just in 7 minutes,  this was generally found during the testing of the electromagnetic railgun.

⚔️WORKING OF ELECTRO-MAGNETIC RAIL GUN⚔️

 🗡️here the electromagnetic railgun is generally consists of a large electrical circuit and generally has several parts: we can generally classified the electromagnetic railgun into five parts namely:

1)  power supply: to the power supply we can generally set it is nothing but the current which is generally required in order to start the electromagnetic railgun and here we generally requires a tremendous amount of current in order to generally operate the electromagnetic railgun.

2) pair of parallel rails: in the electromagnetic railgun we generally have two parallel rails are the tubes which are generally made up of a conductive metal.  near the two arrays are generally placed parallel to each other so that when the current is generally provided to this electromagnetic rays the magnetic field will be generated and then it will be converted into kinetic energy and kinetic energy will generally file the project and with the larger velocity.  since we are making use of a two tubes in the electromagnetic railgun we can consider 1 as positive where is the another as negative,  the connections are similar as we generally used the make the connections in the wire.

3) armature: armature is the conductive metal part in the electromagnetic railgun and the armature bridges is the gap between the rails.

4) the power generator: as we know the generator generally converts the rotational energy of the mechanical energy into the electrical energy but here the original general used in order to provide the extra extra energy that is General required for the electromagnetic railgun in order to fire the projectile.

5) projectile: as I have said earlier here  no gunpowder is used in the projectile the projectile is generally fired by means of using the electric current in the power supply.

 🗡️when the large amount of current is generally provided to the electromagnetic railgun that will generally create the magnetic field in the tubes of the electromagnetic railgun and then after that the force is generally generated and this force is generally called as Lorentz Force.  this Lorentz Force helps the projectile to move in vertical direction with the larger velocity and speed.  since we are not using the gun powder in this mechanism it is not having a limited range we can fire it at  larger distance.  next we are going to see about the merits or the advantages and disadvantages for the demerits of the electromagnetic railgun.

⚔️DISADVANTAGES OF ELECTRO-MAGNETIC RAIL GUN⚔️

 🗡️firstly the more amount of current is generally used in order to fire the projectile means we require a large amount of current in this process.

 🗡️it will not be a problem if you can generally provide to provide the large amount of current but the major problem is that we need a larger capacitor in order to general store this electric current but on today's world we are not developed such a large capacitor in order to so store such a large amount of current so we make use of some cubic metre size to capacitor in order to store the large amount of current and hence this process is not cost effective.

  🗡️resistive heating is one of the major problems in the electromagnetic railgun because since we are using a large amount of current with general develops a large amount of magnetic field near the project will be fired at a very highest speed so a lot of it will be generally generated.  so it is necessary that we need your some mechanism in auto generally cool the electromagnetic railgun from general heating up.

 🗡️the last most problem in the electromagnetic railgun is the melting.

 🗡️since we are using the large amount of current or the tremendous amount of current here there might be chances of the current flow in the reverse direction or in the opposite direction which we can generally called quality as a repulsive force and this repulsive force may cause the wear and Tear problems in the electromagnetic railgun.

 🗡️electromagnetic railgun cannot be used continuously,  since once we generally fire a projectile in the electromagnetic railgun a large heat will be jointly developed and when it requires some certain time in auto generally School the electromagnetic railgun and after a certain period of time it will be gently ready to fire one more projectile.  and this might might be one of the major disadvantage of the electromagnetic railgun change it does not have the continuous  firing   feature. 

⚔️ADVANTAGES OF ELECTRO-MAGNETIC RAIL GUN⚔️

 🗡️Here, no gunpowder is generally used in the electromagnetic railgun.

 🗡️electromagnetic railgun can be used for either for short or long distance fire firing of the projectile.

 🗡️department of DRDO that is the department of research and development organisation have tested this electromagnetic railgun in the year 2017 in the month of November and the testing of railgun have successfully completed and it travels for about the distance of 4600 miles per hour and it has projectile has been fired.

 🗡️but generally in India the use of electromagnetic railgun is generally under the stage of development until now.

 🗡️by this we can generally say that the electromagnetic railgun has both the advantages as well as the disadvantages but in the upcoming future we can generally produce disadvantages and make use convert into advantages of that in the near future we can use it as a major weapon against our enemies,  change the technology is generally developing day by day and the modernization weekend general is in the technology week it will not be difficult for us to generally modify the electromagnetic railgun to  convert the disadvantages in to the advantages and can be used in the near future with more of the advantages so that it can give some more  strength to our  Indian defence system.the countries like United States of America (USA), China, India etc are making use of electromagnetic railgun but in most countries the electromagnetic railgun is under the stage of development. 

HIGH TORQUE ROTOR'S AND THEIR CLASSIFICATION

👷HIGH TORQUE ROTORS 👷

⚡in case of slip ring induction motor and external resistance can be added in the rotor circuit during starting this gives high starting torque and lower starting line current at an improved power factor.  this resistance is then gradually cut from the rotor circuit which would otherwise result in degrees of full  load speed  poor speed regulation more total losses and hence reduced efficiency.  with lower rotor resistance it gives constant speed low sleep less losses and high efficiency.  this is the major advantage of the slip ring induction motor that it gives high rotor resistance at starting and low rotor resistance at normal operating speed.

⚡in case of squirrel cage induction motor there is no provisions made for adding external resistance.  with the resistance is designed in such a way that it gives better running performance than It has high starting current and consequently Low starting torque.  this is the major disadvantage of squirrel cage induction motor although it is having the other qualities of low cost righteousnes and maintenance free operation.  thus the designers have found different ways of improving the starting performance of the motor without affecting the running performance of the motor.

⚡in squirrel cage Induction Motor High starting torque can be obtained by the use of dip bar or double cage rotors.  both these types of rotor make use of skin effect in which distribution of current is not uniform for the alternating current has the 10 tendency to concentrate near the surface of the conductor.  due to this effect effective area of cross section of the conductor is reduced and hence the resistance of the conductor is increased when carrying alternating current.

⚡the solid conductor can be considered to be made up of a large number of Trans is carrying a small part of current.  the inductance of each strand will vary according to the position.  restaurants in proximity ad of the centre are surrounded by a greater magnetic flux and has a greater inductance than near the surface.  due to high reactance at the centre the alternating current flows near the surface of the conductor.  the skin effect depends upon the nature of the material diameter of the wire shape of the wire and the frequency.

⚡Thus the current in the rotor during starting is having the frequency of the supply.  while under running condition the frequency of rotor current reduces to slip frequency.  this variation in frequency change the rotor resistance as it depends on the skin effect.  during starting it gives high resistance whereas it gives low resistance during running condition which is desirable.  does the variation in rotor resistance can be achieved by debba or double cage construction of rotor of induction motor.  both these types of Constructions made use of skin effect phenomenon.

👷DEEP BAR ROTOR CONSTRUCTION👷

⚡there is no constructional difference between stator of the motor and that of the ordinary induction motor.  the rotor consists of a deep Bass short circuited by 2 and rings one on each side.  The Deep and narrow rotor bar of rectangular cross section is shown in the figure 4.13.1(a). The Other rotor bar shapes are shown in the figure 4.13.1(b). the magnetic leakage flux lines are shown by dotted lines now considered that the bar consists of many number of layers of different apps the top and bottom layers are also shown in the figure 4.1 3.1.

⚡the leakage inductance of the bottom strip is greater than that of the toxic as more flux linked with bottom strip compared to the top strip.  all the strips are in parallel electrically.  the bottom strip has greater leakage inductance than the top strip.  during starting the rotor frequency is equal to the state of frequency and hence leakage reactance of bottom state is largest and current in it is least.  the top strip has low leakage reactance and current in it is large.  does the current in Lori active stocks will be greater than that in Hai reactance lower strip and the current will be forced to was the top of the slot and face of current in copper strip will lead that the of the current in the lower one.  thus there is non uniform distribution of current which is shown in the figure 4.1 3.2 due to this non uniform distribution of current and due to the skin effect effective area of cross section decreases.  Hans rotor resistance increases result in high starting torque.

⚡as leakage reactance is proportional to frequency the non uniform distribution of current depends upon the rotor frequency.  in the figure 4.1 3.2 shows a curve indicating alternating current effective resistance to direct current resistance with the change in frequency for the copper bar of 2.5 CM Deep.  the skin effect is maximum when rotor is at standstill.

⚡with the increase in rotor Speed the rotor frequency decreases and the skin effect also decreases.  the reactance of different steps at this low frequency become almost equal and the current density of the conductor cross-section becomes uniform so it is alternating current resistance is equal to direct current resistance.  10 with the dip bar Rota has a low starting current with high starting torque without affecting running performance of the motor.  the net reactance of the dip bar Rota at a standstill is higher than in the normal bar design The breakdown or pull out  torque in deep bar rotor is lower. The torque-slip  characteristics of deep motor and normal induction motor is shown in figure 4.1 3.3.

⚡the equivalent circuit of induction motor is applicable to the rotor also where as proper value of resistance and reactance must be determined for satisfactory running performance.  during starting their values  should correspond to their effective values at lower rotor frequency.

👷DOUBLE CAGE ROTOR CONSTRUCTION

⚡this is another way of obtaining improved starting performance without affecting its running performance.  do it is more expensive it gives better performance than Deep bar rotor construction.

⚡the stator of double cage rotor induction motor is same as that of ordinary induction motor where as its  Rotor  consists of two cages for two layers of bar short-circuited bye and drinks since the upper  cage is having smaller cross sectional area than the lower cage the upper cage is having higher resistance than that of the lower cage.  with equal cross sectional area of two cases the upper cage is made up of high resistance material like brass aluminium bronze etc.  and the lower cage is made up of low resistance material like Copper.  the upper cage and lower kg are separated by a narrow slit aur constriction.

⚡the slot leakage flux pattern is also shown in the figure 4.1 3.4 for The Double cage Rotor.  similar to Deep bar rotor construction The rotor bars in the upper case has less leakage flux linkage and therefore has lower reactance.  the dimensions of their construction control the self leakage flux linking upper and lower bars.  if their construction would have been observed that the main flux would written by means of iron path between the two slots and thereby missing the bus in the lower cages which will not contribute to production of torque in that case.  hence it is see it can be seen that the upper case has higher resistance and lower reactance whereas the lower cages lower  resistance and high reactance.

⚡during starting the rotor frequency is same as data frequency of the supply frequency.  the division of rotor current in upper and lowercase is inversely proportional to their leakage impedances.  at the time of starting the leakage reactance of lower case is very high and consequently its leakage impedance is several times greater than that of upper cage whose leakage reactance is small.  most rotor current flows in the upper cage having lower leakage impedance.  the per cage having high resistance sharing the rotor current results in lower starting current at improve power factor giving high starting torque.

⚡when rotor speeds up the rotor frequency decreases which decreases the leakage reactance of lower cage.  at normal operating Speed the reactance  difference between the two cages is negligible small.  Hans dead division of rotor current in this case is mainly decided by the resistance of the two cages.  as resistance of upper kg is very high most of the current flows through the lowercase giving excellent operating characteristics under the running condition.  it can be noted that the starting current is confined mainly with upper cage so that there is frequent starting of motor then it would cause overheating and burning of upper cage.  the torque slip characteristics of double cage induction motor are shown in the figure 4.1 3.5.  another type of double cage rotor construction is also possible which is shown in the figure 4.1 3.6.  the slot leakage flux pattern for this type of construction is also shown in the figure.  the approximate equivalent circuit of double cage rotor induction motor is shown in the figure 4.1 3.7. Though  the two cages are somewhat coupled magnetically they can be treated as independent for simplicity and it use approximately same results.  the two cages are assumed to be parallel while drawing the equivalent circuit.

⚡the secondary upper case resistance and secondary lowercase resistance R the current in the upper and lower cases respectively referred to the stator secondary upper cage resistance and secondary lower cage resistance  of uppercase and lowercase referred to the stator whereas secondary uppercase reactance and secondary lowercase reactance are the leakage reactance of the two cases referred to the stator of the motor. 

👷⚡COMPARISON OF SINGLE CAGE AND DOUBLE CAGE ROTOR⚡👷

ANDROID VERSIONS AND THEIR FEATURES

💁‍♂️ANDROID VERSIONS AND THEIR FEATURES 💡

✏️The following are the features of the respective versions:

ANDROID 1.0 :  first full version of Android was released on September 23rd 2008 Wi-Fi and Bluetooth are supported quite slow in operating copy and paste feature in the browser is not present.

ANDROID 1.1: released on February 9th 2009 initially for the HTC dream only.  Android 1.1 was known as "PETIT FOUR" internally, do this name was not use officially. Details and reviews available when a user searches for business on maps. Longer in Screen timeout default when the speakerphone plus ability to show hide dial pad .Ability to save attachments in messages and support added for mark you in system layouts.

ANDROID CUPCAKE 1.5:  released on April 30, 2009 added auto rotation option. Copy and paste features added in the web browser and increased internet and performance but not up to the required level.

ANDROID DONUT 1.6: released on September 15, 2009 voice search and search box where added. Faster operating system boot X and fast web browsing experience and typing is quite slower.

ANDROID ÉCLAIRS 2.0/2.1: released on October 26, 2009 it support Bluetooth 2.1. The typing is virtually improved by means of the virtual keyboard with smart dictionary option. But the disadvantage of the Android Éclairs is no Adobe Flash media is supported.

ANDROID FROYO 2.2: Android Froyo was generally released on May 20, 2010. Eventually some modification of Android eclipse is support Adobe Flash 10.1 and the Android froyo has got improved application launcher with better browsing performance.

ANDROID GINGERBREAD 2.3: Android Gingerbread was general released on December 6, 2010. This Android version has got updated user interface efficiency and speed. The Android Gingerbread also comes with the special feature that is the internet calling and some more features of the Android Gingerbread are:
one-touch word selection and copy and paste option.
  👉It was the most successful version of the Android compared to the all the previous versions.
👉But the main disadvantages of the Android Gingerbread 2.3 does not support multi core processors.

ANDROID HONEYCOMB 3.0: this version of Android was released on February 22nd 2011. Since it is a modification of Android Gingerbread it supports multi core processors. The Android honeycomb 3.0 has got the special ability to encrypt all user data.
👉But the only disadvantages of the Android honeycomb 3.0 is that it is only available for tablets and not for smartphones.

ANDROID ICE-CREAM SANDWICH (ICS) 4.0:  Android ice-cream was released on November 14, 2011. A virtual button in the UI. A new typeface family for the UI A, robot.
⚡Android ice-cream has the ability to shut down apps that are using data in the background and this feature separate is from other Android versions.

ANDROID JELLYBEAN 4.1/4.2/4.3: ⚡Android Jelly Bean was released on June 27th, 2012.  Android Jelly Bean has got smoother user interface compared to the other Android versions. The only disadvantages of the Android Jelly Bean is that it is restricted profile and others.

ANDROID KIKAT 4.2: Android Kit-Kat was general released on October 31st 2013.
The advantages of Android Kit-Kat is that it go it is got better number in management and improved Google Now.  👉It’s also got some special features like smarter caller ID and others.

ANDROID LOLLIPOP 5.0/5.1: Android lollipop version released on October 15, 2014.  Android lollipop has some got some better features like Wi-Fi and Bluetooth protection. After some months it is also got the feature like better device protection too. In Android lollipop we can also how the feature like the notification can also be flicked away.

ANDROID MARSHMALLOW 6.0: Android Marshmallow was general released on October 5th, 2015. In the previous version of Android lollipop we just had the Google Now version button Android Marshmallow 6.0 the Google Now will read your screen and tell you what it sees.  some more additional features were added to Android Marshmallow 6.0 case by case app permission is given and fingerprint support is also provided could recognise the user's identity so that most of the personal details of the user can be hidden from others.

ANDROID NOUGAT 7.0:  Android no god was general released on August 22nd, 2016 and the best feature of Android no got is that it has got the split screen mode this feature generally makes it look different from other versions of Android.  Android nougat 7.0 has also got extra feature like quick switch display size mode.

ANDROID OREO 8.0: Android Oreo 8.0 general released on August 21, 2017.  Android Oreo 8.0 will allow app will have the different notification channels where each channel can be set for different alert types.  Android Oreo 8.0 has got some special features like picture-in-picture multitasking can be done welcome back to other versions of Android. The highlight feature of the Android Oreo 8.0 is passport auto fill.

ANDROID PIE 9.0: (codenamed Android P during development) is the ninth major release and the 16th version of the Android mobile operating system. It was first released as a developer preview on March 7, 2018, and was released publicly on August 6, 2018.As of June 2020, 32.43% of Android devices run Pie, making it the most popular Android version.
1) Tap into gestures
2) a better Overview
3) a smarter battery
5) improved notifications
7) App Actions
8) have a slice
9) Digital Wellbeing

SPECIAL FEATURES
👉Indoor positioning with Wi-Fi RTT.
👉Display cut-out support.
👉Notifications. Enhanced messaging experience.

👉Channel settings, broadcasts, and Do Not Disturb.

👉Multi-camera support and camera updates.
👉Image-Decoder for draw-able and bitmaps.
👉Animation.
👉HDR VP9 Video, HEIF image compression, and Media APIs.

ANDROID 10: Android 10 is the tenth major release and the 17th version of the Android mobile operating system. It was released on September 3, 2019. Android Q is now Android 10. While some features need some extra polish, the changes you'll find are largely valuable improvements that strengthen Android's core experience. Dark mode is great, and so are Google's attempts to make its many privacy options easier to control.
👉Dark Theme. Users have long been asking for a dark mode, and Google has finally answered
👉Smart Reply in all messaging apps
👉Enhanced location and privacy tools
👉Incognito mode for Google Maps
👉Focus mode
👉Live Caption
👉New parental controls
👉Edge-to-edge gestures