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The answer to the question about the arrangement of a modern hybrid at the same time is simple and difficult. In the general sense, this is a car whose power plant consists of an electric motor and internal combustion engine, which in one way or another jointly turn wheels. This is enough to explain to anyone uninitiated, which means the mysterious word Hybrid on the body of the car’s usual appearance. But you should dig deeper – and the head is turning to the amount of technical solutions and layout options wound up by the creators of modern hybrids! To interfere in a large number of terms and engineering solutions is easier than simple, but in our material we have figured out what hybrids are in general and how they are all constructed. The first criterion by which all hybrid cars can be divided – how developed their ability to move on an electric trailer.
ICE = Internal Combustion Engines (cars with internal combustion engines)
HEV = Hybrid Electric Vehicle (hybrid cars)So what better?
A hybrid future is definitely a plug-in design, because it is they who provide real fuel economy. In addition, most “plug-ins” are two cars in one: silent and smooth electric plus gasoline with explosive dynamics, which provides a heavy electrical boost. However, for the full use of such a car, the owner should be able to provide its charging infrastructure. Otherwise, it’s easier to stop on a regular full hybrid that does not have a functional connection to the outlet – let it run on electricity and worthless compared to plug-ins, but also weighs the whole design less and cheaper. Meaning in extinct moderate hybrids, which are unable to move without the participation of ICEs, practically absent – the effect of the use of electric trains here is unlikely to justify superfluous weight and higher cost compared with non-hybrid versions. There is a future in micro-hybrids: the ratio of costs to the effect achieved with this technology looks beneficial. Regarding the mechanical circuit, this is more of an adjustment issue: the end user should not worry about how and by which the power and energy streams are distributed in the car’s interior – the industry knows examples of both excellent and not very perfect work of any of the known schemes.
PHEV = Plug-in Hybrid Electric Vehicle (plug-in hybrids)
REEV = Range Extended Electric Vehicle (electric vehicle with auxiliary vehicle for prolonged stroke)
FCEV = Fuel Cell Electric Vehicle (Electric Vehicle on Hydrogen Fuel Cells)
BEV = Battery Electric Vehicle (Rechargeable Electric Vehicle)
The blog is about auto-hybrids – that is, we are interested in points from the second to the fourth in the list: HEV, PHEV and REEV. But this general classification does not fully cover all possible combinations of internal combustion engines with electric motors and electric generators, and we will try to understand what kind of constructive decisions are and what they can lead to this classification.
Microgribles – the simplest form of hybrid life (Micro HEV)
The most formidable form of hybridization is the advanced version of the “start-stop” system. Here, no electromotors are used, and the hybrid such technology is rather conventional, so immediately allocate microgribles in a special category outside of any classifications. In such cars a special powerful starter is capable not only to untwist the engine for launch, but also to work as a generator during recuperative braking. We take “free” electricity – save on the parasitic load of the ICE (which does not need to produce on-board electricity in addition to the main traction duties), and hence fuel consumption. Obtained literally while driving and stored in an enhanced battery and / or a special storage device, the electric energy then goes on to restart the internal combustion engine with the operation of the “start-stop” system, the power supply of the climate unit, electric drives, light engineering and other on-board devices, and saved on this fuel – for additional kilometers of mileage. Similar technologies are used by many manufacturers: i-ELOOP from Mazda, e-HDI from Peugeot, Blue Drive from Hyundai and others.
Higher degree of electrification: plug-in type hybrids (PHEV)
But true, full hybrids are still capable of more both in terms of fuel economy and in terms of traction capabilities. All because their electric motors not only accumulate electricity in the role of generators for charging batteries, but also rotate the wheels in conjunction with the internal combustion engine. Only do it differently. The most advanced designs provide the opportunity to move both with the help of joint efforts of the ICE and the electric motor, as well as on a pure electric motor, and for quite a long time. To do this, their battery has an increased capacity, an electric motor – the highest power (70-100 hp and above), and beside the hatch of fuel tank in the body there is also a port for connecting an electric cord for charging from the usual socket.Recuperation is one of the basics of all hybrid technologies and a mandatory (but not always the only one) way to charge the batteries of any hybrid (which is true in the case of PHEV). It represents the transformation of kinetic energy into electrical (instead of thermal in conventional cars) and the storage of the latter in a traction battery. This process becomes possible when the machine is rolling or slowing down, and the wheels are rolled up by an electric motor generator, which, as a result, produces electricity. All because thanks to the times of a larger charge than conventional hybrids, the “plug-in” batteries can overcome the electrodes without a single flash in ICU cylinders up to 50 kilometers. This is quite a decent distance from the city standards, harmless to the environment, which can be repeated again and again under the condition of regular “refueling” of the batteries from the outlet. But the average indicator, taking into account the conditions of movement and the difference in technical characteristics – about 25-30 km. That too, however, a lot. Indeed, the ability to fully travel on electricity in short urban travel is a serious competitive advantage over other, more simple hybrids, which are unlikely to reach the electric trailer until the next traffic light!
Less degree of electrification: full and moderate hybrids (HEV)
Hybrid cars that can not charge from the socket are also divided into subspecies: it’s full and so-called moderate (mild in English-speaking sources). The first ones due to the greater volume of the batteries, the higher power of the electric motor are able to move exclusively on the electric motor, usually within 2-4 kilometers, while the latter use the weak electric motor only as an assistant for the ICE and “on the batteries” (due to their modest volume and overall primitivism of the structure systems) are not able to pass a meter. In this case, moderate hybrids store energy only with the help of recuperative inhibition, and also complete with the help of an internal combustion engine, usually coupled with a separate generator.
Scheme: sequential hybrids (REEV)
In the case when the internal combustion engine in principle does not rotate the wheels mechanically, the hybrid is essentially an electric vehicle with an on-board generator of electricity, the role of which is performed by the ICE. Such hybrids are called sequential. This scheme is simple, since there is no need to build a complex transmission – electric motors rotate the wheels through a single main transmission, which serves to generate the required torque. But the class of successive hybrids today is represented by single models, since the effectiveness of such a solution is ambiguous. After all, the energy of combustion of fuel must be converted first into a mechanical, then mechanical to electric, and at the end of the electric – directly to the rotation of the wheels.
One of the electric motors of the system serves as a starter and generator, and the other is pulling and recuperating electricity during deceleration. Due to the features of the planetary mechanism, the ICE is not directly connected to the wheels, and part of its energy is always given to the rotation of the charging battery and feed the traction motor of the generator. For a detailed analysis of the device, the hybrid unit Toyota needs a separate large material, but within the framework of this general one must understand the main thing: the traditional transmission is replaced by a planetary transmission and a controlling power module (ICE and two electromotors-generators) electronics – depending on the needs of the driver, the traction electric motor issues a certain power alone or in combination with the internal combustion engine, and excessive traction by the last means of the planetary mechanism goes on the rotation of the second motor-generator and, accordingly….