The idea of wireless energy transfer dates back to the 19th century, and was first demonstrated by the Serbian genius Nikola Tesla in 1893 at the World's Columbian Exposition in Chicago. The technology that seemed like a miracle has now become firmly established and is found everywhere, from funny but useless levitating light bulbs to really comfortable things type of wireless chargers for mobile devices.
The technology of transferring energy to a smartphone battery without using a connector and cable appeared a long time ago, back in 2008, that is, just a year after the presentation of the iPhone and the birth of the smartphone market in its current sense. Manufacturers of devices and components created the Wireless Power Consortium, the purpose of which was to unite different manufacturers to create universal wireless charging technology. Thanks to this collaboration, Qi technology emerged - read “Qi” (less commonly “Chi”) and denoting “energy” or “life force” in Chinese philosophy. Thanks to the work of the Consortium, the requirements and principles of operation of devices and charging stations supporting the Qi standard were determined, as a result of which users today can use induction mats without regard to the smartphone brand and without changing accessories after purchasing a new device.
It cannot be said that after the approval of the Qi technology standard and the start of its use, all other companies curtailed their development. There is constant research being done that would provide significantly faster charging speeds or greater distance between the pad and the device - but none of this is ready for mass production and in the absence of decent revolutionary ideas More and more smartphone manufacturers are starting to implement support for the Qi standard. Even Apple and Sony “gave up” by adding support for wireless charging to the 2017-2018 range of smartphones, and the list of outsiders so far only includes inexpensive Chinese brands that try to save on components or do not want to change the well-established production of the same type aluminum cases. However, the situation may soon change, for example, according to rumors, the flagship Xiaomi Mi7 will support charging using the Qi standard.
The accessories market is also constantly evolving. Wireless stations are beginning to be supplied for public spaces, induction pads are found in cars or sold as additional accessories for cars, many solutions are emerging for home use. And most importantly, most often the prices for wireless chargers are not so high as to deny you the convenience of using them. Branded accessories from manufacturers can be sold at a very high cost (4-7 thousand rubles), but there are always alternatives from third-party manufacturers that are not inferior in design, quality and technology. For example, we are now testing the Expert NBE-WC-12-01 model (1890 rubles) with support for an extended version of the Qi Fast Charge standard and a current of 1.2A.
This Nobby model is a compact platform round shape. The manufacturer uses high-quality black plastic that is pleasant to the touch; there is also a luminous ring that changes color when the smartphone starts charging. The accessory does not take up much space on the table, and most importantly, it has a classic flat surface. This is true for smartphones like Sony Xperia The XZ2 has a curved rear panel that may roll off some charging stations but sits securely on Nobby accessories. There is no risk of putting your smartphone in the wrong way and then finding it next to the mat not charged.
We tested the Nobby device with the iPhone X, Samsung Galaxy S9 and Sony Xperia XZ2 - in all cases it was very convenient, since you do not need to look for a wire, connect and disconnect it, and you can put the smartphone on the pad at any time. In terms of speed, the Expert NBE-WC-12-01 model works as advertised and charges the smartphone really quickly.
As for the principle of operation of wireless charging, everything is quite simple. Base station consists of an induction coil that creates an electromagnetic field when alternating current is applied. The device contains a similar coil that can capture this field, converting the resulting energy into direct current - and transferring it to the battery for recharging. However, this is an explanation for the average consumer; techies know that in fact the system is more complex and it also uses current converters, rectifiers, controllers, voltage regulators and other circuit components. But is this really important for the average consumer to know? Other questions seem much more interesting: the impact on health, safety of use and restrictions.
Despite the appearance of an additional radiation source in the house, there is no need to worry about this. Qi standard charges use non-ionizing frequencies, which are guaranteed not to have any impact. harmful effects to your health. And both humans and small domestic animals. Over the ten years of work of the Consortium, many studies have been carried out, and all of them have confirmed the possibility of using charging stations without restrictions. As for safety, there is also complete order: charging is possible only with Qi-compatible devices, there is a temperature control system for sudden heating. Even if a foreign object gets on the charging mat, there will be no problem.
As for the restrictions, the only thing that manufacturers cannot “defeat” so far is metal cases. From the first devices like the Lumia 920 to the iPhone X, smartphones have had to experiment with materials. Previously, it was plastic, which was used even in the premium segment, but now it has been replaced by more spectacular glass. Perhaps this is why iPhone owners have been deprived of the ability to charge their smartphones on mats for so long. At the time of the Quartet, Qi was not yet so popular, and after that the company relied on metal for a long time. Now, partly due to the desire of manufacturers to implement wireless charging functionality and partly due to spectacular design, glass has become the most popular material for the back panels of flagships. The entire current iPhone line, Samsung Galaxy flagships, the latest Sony Xperia XZ2 and XZ2 Compact, LG V30 ThinQ and Nokia 8 Sirocco - these and other top devices support Qi technology.
As a result, we cannot think of any reason not to use Qi chargers if the smartphone supports this technology. A wireless mat is very convenient because you can simply place the device on it, rather than looking for wires and a connector. Accessories are inexpensive, they are harmless and safe. We have already mentioned the Nobby brand and decided to talk about how we use it in the editorial office. The Expert model was chosen as the best option for office use - at work, we most often charge only one device and higher speed is very important to us. For example, if you urgently need to get ready for a meeting. However, in model range Nobby accessories also have other wireless chargers. For example, the Nobby Practic NBP-WC-10-01 model has an outgoing current of 1A (that is, it charges more slowly), but is equipped with two USB ports for wired connection of devices. This solution is well suited for home use, since it allows you to take up only one outlet and wirelessly charge your smartphone and other devices such as smart watches or headphones.
How does wireless smartphone charging work? August 21st, 2016
Nowadays I hear more and more often about wireless charging. Four months ago, when I was looking for a new car, I saw a Kia Sportage with a built-in charger. I also thought, who is this intended for, just a few? It seemed that for this you need to have some kind of cool phone model or some expensive equipment. But it turns out that my phone is also average cost supports this technology. I thought about it, I don’t know the principles of how it works at all. It seemed to me that this technology is still quite “far” from the average person, but it is already nearby and completely accessible.
Let's take a closer look...
It turns out that the principle of operation of a wireless charger is very simple - just place the gadget on a special panel for it to charge. The accessory is based on the operating principle of an induction coil.
Cordless toothbrushes long time are already using wireless charging. The technology has traditionally been plagued by problems of low efficiency and slow charging, but these weren't critical shortcomings for a toothbrush or electric razor that you only use for a few minutes every day. Using inductive charging is safer from the point of view that there is no wire, and it will not short-circuit, and you will not accidentally touch wet hands to areas with poor insulation.
This method of energy transfer has become very popular recently. In 2015, the globally popular brand began selling furniture that would have a wireless charging module built into it. Today, all flagship smartphone models support Qi.
It is expected that transmitters or, in other words, modules will soon be found in airports, restaurants, cinemas, fast food outlets, shopping centers, which will allow you to charge phones and tablets at any time. In fact, this will make life easier for users of mobile gadgets. We are entering new era, where it is not at all necessary to carry wired chargers with us everywhere for all the devices we use.
The wireless power standard is called Qi. In Russian transcription the word is pronounced as “Qi”. The standard bears this name in honor of the term of Eastern philosophy and means the flow of energy. It is developed by the Wireless Electromagnetic Power Consortium WPC. This organization unites global electronics manufacturers and sets itself an important task - to standardize the process of charging gadgets using the induction method. In the near future, all devices will be able to be charged without connecting to the network. It's incredibly convenient. Each of us has at least once encountered a situation where a smartphone is discharged. We have to urgently look for a way out. Soon, wireless charging modules will appear in all public places, as well as in every user’s home.
At home, you can simply place the module in a convenient place, and it will never get lost, unlike wired “charging”. You just need to place the gadget on it and wait a bit until the battery capacity is replenished. The operating principle of wireless charging is based on the properties of an induction coil to transmit electric current. In a school physics course, we were taught that when an induction coil is connected to a power source, a magnetic field appears in it perpendicular to the turns of the coil. Thus, if you place two coils within the range of a magnetic field and at the same time connect one of them to a power source, then voltage will appear in the second coil. It is important to take into account the fact that the two induction coils should never touch each other. This simple principle is used in the operation of wireless chargers that support Qi technology.
There are two varieties of the Qi standard. The first involves charging at low power - 5 watts, and the second - at high power - 120 watts. High-power Qi is currently not produced by manufacturers due to objective factors. Using Qi at 120 watts, you can charge your laptop. Qi at 5 watts is used to replenish the battery capacity of tablet computers and phones. It should be noted that tablets and smartphones require different amperages. A wireless charger for a phone produces a current of 1 ampere, and for a tablet computer - 2 amperes. When choosing an accessory, be sure to pay attention to these characteristics.
A modern wireless charger consists of two components. One of them is built directly into the gadget, which supports Qi and is called a wireless charging receiver. Essentially, it is a receiver that conducts electrical current to the battery. The second component is called the transmitter. If you mean buying a wireless “charging”, we are talking about a transmitter. They are the most different forms and sizes. The most common types are round and rectangular transmitters.
To better understand how wireless charging works, you should consider that a magnetic field can transmit not only electric current, but also data about bytes and bits, which the developers of the Qi standard took into account. Interaction between the coils will occur only at the moment when the gadget with a built-in transmitter is close to the transmitter. If the accessory for charging the gadget operates in the background, then the pulse sent every 0.4 seconds by the transmitter will not change the voltage in the coil built into the transmitter. It can be concluded that modern accessory knows how to recognize in which mode to function. As soon as a smartphone is nearby at a distance of several centimeters, the voltage in the induction coil will drop sharply and the device will switch to active work. As soon as the smartphone’s battery is charged, a corresponding signal will switch the charger into the background. We can conclude that modern wireless accessories for replenishing battery capacity are energy efficient.
Even more graphs and formulas
Some users mistakenly believe that Qi wireless charging may be harmful to health. The fact is that magnetic radiation is not ionizing. In terms of its effect on the body, it is similar to a mobile phone signal, a Wi-Fi signal, or a radio signal. At the same time, the mobile network signal coming from the tower is stronger and continuous, while electromagnetic radiation disappears immediately after charging the smartphone battery. The power of wireless chargers is 5 watts. It is not enough to have an impact on human body. ABOUT negative impact we can only talk if the power of such devices is 120 watts. But such models are not produced on an industrial scale. This explains the lack of wireless chargers for laptops. It is important to know that wireless battery charging technology has long been used in many models of electric shavers and electric toothbrushes, which once again proves its safety.
Prospects
This inductive charging can be convenient, but the short range is a problem. This dramatically reduces the usability of this technology. Will this change? May be. There has been a lot of research into the potential of wireless charging and there have been advances in range in various technologies. Lasers, microwave ovens and more powerful inductive charging options were able to achieve longer transmission distances. Disadvantages prevent the spread of this too powerful radiation of the above mentioned technologies. You might get burned or worse. It is difficult to say who will take the palm in this market. The first candidate is Apple, because the company has patented a device that can supposedly charge from a distance of up to one meter. The Wireless Power Consortium is also constantly looking for best options. And then there's Intel, which recently announced that it's working on integrated magnetic device technology that will fit inside a laptop and distribute power to nearby smartphones and peripherals.
sources
Even after wireless connection connection to the Internet has become commonplace, the transmission of energy without wires is still perceived by many as Science fiction. However, over the past few years, active research has been carried out in this direction, and now the first commercial devices that allow equipment to operate without another type of wire are already available for sale.
The wireless charger market sector experienced a real boom in the fall of 2009, when companies, one after another, began to announce inductive charging devices. The first samples of wireless chargers were not certified, so they only supported a clearly limited set of chargeable devices.
The situation changed radically at the end of the summer of 2010, when the Wireless Power Consortium, which included the largest electronics manufacturing companies, approved a new standard for wireless power transmission Qi 1.0 with a level of no more than 5 W
The Wireless Power Consortium is currently working on the next version of Qi. It is known that new version will allow you to transfer more energy over a distance and charge more “serious” equipment, such as netbooks, laptops, tablets.
This icon (logo) marks all electronic devices that support Qi wireless charging.
Composition and operating principle of inductive charging
Source of energy. The basic operating principle of inductive charging is based on the use of the effect of electromagnetic induction. This requires the presence of two coils and alternating current, which will create a non-static electromagnetic field. The first coil is located in the transmitter and connected to the network.
Energy receiver. The receiver also contains a coil in which current occurs only when the electromagnetic field changes. This can be achieved by moving the receiver in space or by using alternating current on the transmitter. If anyone is afraid that he might be hit by a spark running between the transmitter and the receiver, then he is mistaken, since there is no transfer of charge through the air - the alternating magnetic field created by the first coil simply forces the electrons in the receiving device to move.
The basic operating principle of inductive charging is very simple and is based on electromagnetic induction. Unlike classic chargers, their wireless counterparts use an additional conversion unit, similar to a conventional transformer, instead of a copper conductor, which leads to a slight decrease in efficiency.
The efficiency of this unit, according to different manufacturers, ranges from 50% to 90%. The Wireless Power Consortium puts an intermediate figure at 70%.
The benefits of new wireless charger technology
Let's try to list all the advantages of the new technology:
Convenience. The phone owner simply places the device on a small flat panel, without worrying about connecting wires or accurately positioning the device on the transmitter.
Versatility. Users of certified equipment will be able to recharge it using any Qi-compatible charging model.
Economy. Although overall efficiency inductive charging and lower than traditional ones, due to the almost complete absence of energy consumption when idle (0.0001 W), they take the lead during long-term operation.
Practicality. The inductive charger is designed to be able to simultaneously “connect” several devices. Unlike traditional chargers, this does not require additional sockets.
Well, from an aesthetic point of view, the absence of unnecessary wires has always been a big plus.
Available wireless chargers
Transferring energy over a distance is real new technology, which was developed for a number innovative projects. IN recent years Many large companies have been researching wireless power transmission for use in conventional technology. Suffice it to name Intel, Sony, Sanyo, Fujitsu, Energizer. And although some innovative developments never made it out of the laboratory, some products are already available on the market.
Powermat was one of the first to introduce inductive charging. Its models support iPhone, iPod, BlackBerry, and more recently Android.
Qi wireless charger - Powermat3
Such a limited list is due to the fact that initially not a single phone has a receiver for receiving energy. It is installed into the smartphone later along with a new battery and, of course, special battery versions are available only for the most popular models. Usually the battery with the receiver is slightly larger than its predecessor, but in general, due to the well-thought-out design, it practically does not stand out in the device.
GEAR4 takes a slightly different approach. Instead of a battery, the charger comes with a special case for the iPhone, which must be on the phone at the time of charging. The rubber pad does not need to be removed once the battery is fully charged as it can perform normal protective functions.
The most common wireless charger today Energizer Qi One of the first to be certified in accordance with the Qi 1.0 standard and can charge up to three devices simultaneously. At the same time, an additional USB port is located on the transmitter body, which allows you to add another device
Wireless Charger - Energizer Qi
Wireless power transmission systems aren't just for smartphones. A year and a half ago, Energizer began releasing the Wiimote Induction Charging System for wireless controllers for the Nintendo Wii. Unlike analogues from other manufacturers in in this case You don't even have to remove the silicone covers from the Wiimote. The cost of the listed chargers complete with battery usually ranges from $50 to $150
Another Energizer device, but this time highly specialized. Designed exclusively for charging Nintendo Wiimote
Although the Qi 1.0 standard does not provide the ability to transmit enough energy to power large devices, some manufacturers have developed their own systems for recharging laptops. More than a year ago Dell introduced a 16-inch model Latitude Z with a body thickness of just over 1.25 cm and a weight of about 2 kg, which can be charged wirelessly while on a special stand. The starting price of the laptop was $3645, and now, depending on the configuration, it is around $2000.
However, mass production of universal inductive chargers capable of charging laptops from any manufacturer will have to wait another couple of years.
The near future of wireless power transmission
It is obvious that in the near future all the efforts of researchers will concentrate on solving the following problems: increasing the efficiency of devices, increasing the amount of transmitted energy and distance. You should also expect that new inductive charging models will be almost universal and will be able to charge mice, portable consoles, phones, cameras, GPS and other devices.
Probably, soon all portable gadgets and mobile phones will be equipped with Qi-compatible receivers by default, so that they do not have to be purchased along with a new battery.
Last fall, Fujitsu announced that it would be mass-producing the next generation of inductive chargers that can charge mobile devices 150 times faster than the first prototypes. Moreover, the efficiency of energy transfer in such models will be at least 85%.
In general, considering that a year ago Sony presented a working prototype of a system transmitting 60 W of energy, and WiTriCity announced the presence of devices capable of transmitting energy over a distance of 2 meters, it is possible that such technologies will become commonplace in a few years.
You can look into the future and a little further - already now Nissan demonstrates a prototype electric vehicle charger that can charge small electric cars in just 3 hours. At the same time, engineers claim that the efficiency of such a system is the same or even higher than that of conventional wired charging of cars.
There are no similar entries.
Today it is already difficult for us to imagine our life without mobile gadgets. This has led to a huge number of wires accumulating near household outlets, among which it is not so easy to find the necessary “charging”. In this case, a wireless charger will help solve the problem. The principle of its operation is very simple - just place the gadget on a special panel for it to charge. The accessory is based on the operating principle of an induction coil. This technology is called Qi. She has become very popular lately. In 2015, the globally popular brand began selling furniture that would have a wireless charging module built into it. Today, all flagship smartphone models support Qi. It is expected that transmitters, or, in other words, modules, will soon be found in airports, restaurants, cinemas, fast food outlets, and shopping centers, which will allow phones and tablets to be charged at any time. In fact, this will make life easier for users of mobile gadgets. We are entering a new era where it is not necessary to carry everything with us everywhere for all the devices we use.
Wireless chargers for gadgets with support for Qi technologyThe wireless power standard is called Qi. In Russian the word is pronounced “Qi”. The standard bears this name in honor of the term of Eastern philosophy. It is developed by the Wireless Electromagnetic Power Consortium WPC. This organization unites global electronics manufacturers and sets itself an important task - to standardize the process of charging gadgets using the induction method.
In the near future, all devices will be able to be charged without connecting to the network. It's incredibly convenient. Each of us has at least once encountered a situation where... We have to urgently look for a way out. Soon, wireless charging modules will appear in all public places, as well as in every user’s home. At home, you can simply place the module in a convenient place, and it will never get lost, unlike wired “charging”. You just need to place the gadget on it and wait a bit until the battery capacity is replenished.
The operating principle of wireless charging is based on the properties of an induction coil to transmit electric current. In a school physics course, we were taught that when an induction coil is connected to a power source, a magnetic field arises in it, perpendicular to the turns of the coil. Thus, if you place two coils within the range of a magnetic field and at the same time connect one of them to a power source, then voltage will appear in the second coil. It is important to take into account the fact that the two induction coils should never touch each other. This simple principle is used in the operation of wireless chargers that support Qi technology.
There are two varieties of the Qi standard. The first involves charging at low power - 5 watts, and the second - at high power - 120 watts. High-power Qi is currently not produced by manufacturers due to objective factors. Using Qi at 120 watts, you can charge your laptop. Qi at 5 watts is used to replenish capacity and phones. It should be noted that tablets and smartphones require different amperages. A wireless charger for a phone produces a current of 1 ampere, and for a tablet computer - 2 amperes. When choosing an accessory, be sure to pay attention to these characteristics.
Energy efficiency of the Qi standard
A modern wireless charger consists of two components. One of them is built directly into the gadget, which supports Qi and is called a wireless charging receiver. Essentially, it is a receiver that conducts electrical current to the battery. The second component is called the transmitter. If you mean buying a wireless “charging”, we are talking about a transmitter. They come in a variety of shapes and sizes. The most common types are round and rectangular transmitters.
To better understand how wireless charging works, you should consider that a magnetic field can transmit not only electric current, but also data about bytes and bits, which the developers of the Qi standard took into account. Interaction between the coils will occur only at the moment when the gadget with a built-in transmitter is close to the transmitter.
If the accessory for charging the gadget operates in the background, then the pulse sent every 0.4 seconds by the transmitter will not change the voltage in the coil built into the transmitter. We can conclude that a modern accessory can recognize in which mode to operate. As soon as a smartphone is nearby at a distance of a few centimeters, the voltage in the induction coil will drop sharply, and the device will go into active operation mode. As soon as the smartphone’s battery is charged, a corresponding signal will switch the charger into the background. We can conclude that modern wireless accessories for replenishing battery capacity are energy efficient.
Is Qi technology safe?
Some users mistakenly believe that Qi wireless charging may be harmful to health. The fact is that magnetic radiation is not ionizing. In its effect on the body, it is similar to a mobile phone signal, a radio signal. At the same time, the mobile network signal that comes from the tower is stronger and continuous, while electromagnetic radiation disappears immediately after charging the smartphone battery.
The power of wireless chargers is 5 watts. It is not enough to have an effect on the human body. We can talk about a negative impact only if the power of such devices is 120 watts. But such models are not produced on an industrial scale. This explains the lack of wireless chargers for laptops. It is important to know that wireless battery charging technology has long been used in many models of electric shavers and electric toothbrushes, which once again proves its safety.
Which smartphones support wireless charging?
First of all, we want to note that not all gadgets today support the wireless charging function. Apple intentionally markets products that are not Qi compatible. In this case, we recommend purchasing a special case with a built-in induction coil.
Flagship devices generally always support Qi technology. These include such popular smartphone models as Samsung Galaxy S6, Sony Xperia Z4v, Samsung Galaxy S6 Active, Google Nexus 6, Motorola Droid Turbo, Nokia Lumia 930, Samsung Galaxy S6 Edge. Already, dozens of models from various manufacturers can be charged using a wireless accessory, which provides maximum ease of use for users.
Is it possible to make wireless charging yourself?
Wireless chargers are quite expensive, considering that they are a regular induction coil. The question arises: “How to make a module with your own hands?” Basically, if you have knowledge of basic physics and special equipment for measuring strength and power electric current, it won't big problem. Fans of radio electronics are capable of assembling even different ones. simple devices, but we do not recommend ordinary users to conduct such experiments.
On the aliexpress.com website you can find separate wireless device receivers for some smartphone models, including the , Google Nexus line. It is quite easy to install it on your phone. Under the cover of the device there are two contacts, which provide a positive and negative pole. All you need to do is buy and connect the receiver, after which you can conduct a wireless charging test. This solution is optimal if you somehow got a wireless charger, for example, you were given a gift, and your gadget model does not yet support the Qi function.
Wireless battery charging technology is gaining increasing popularity in modern world. In the future, it will be possible to replenish the battery capacity in many public places. Expected to be wireless chargers stadiums, parks, restaurants, cinemas, fast food will be equipped. When purchasing smartphones, we recommend paying attention to support for the Qi function, which is present in all flagship models of 2015.
