How a hybrid works. hybrid engine

21.10.2019

More and more, in recent years, people are thinking about the environment. The auto industry is no exception. Every year, environmental standards are rising, and with this, vehicle engines are being modernized and improved. A hybrid engine is one of the solutions to improve the environmental friendliness of a car.

What is a hybrid engine

What is a hybrid engine and its device? The very word "hybrid" is translated from Latin as "cross". In fact, this is a mixture of the classic version of the power unit and the electric motor. So, the drive of the driving wheels is carried out by rotation using a conventional internal combustion engine or an electric motor.

Each of the power units performs a specific function in motion. So, when the vehicle is in city traffic jams, the movement is carried out with the help of an electric motor, but on the highway, a gasoline power plant comes into operation.

Advantages of a hybrid

Perhaps the biggest plus in using a hybrid powertrain is its economy. As a rule, such an engine consumes 25-30% less fuel than standard gasoline engines.

The second positive point is the high environmental standard. As fuel consumption decreases, less exhaust emissions enter the ecosystem.

The third plus is that the batteries for the electric motor are charged from a gasoline engine and if they sit down, you can always switch to gasoline. This also includes the same specifications. In terms of power characteristics, the “hybrid” is in no way inferior to a conventional motor.

The "hybrid" engine feels best in the urban cycle of use, where there are frequent stops. In this case, basically, the electric motor itself works. In many countries, "hybrid" cars are driven by city police.

Cons of using a "hybrid"

The first disadvantage worth noting is the expensive repair of hybrid motors. The manufacturers of the "hybrid" explain this by the fact that the power unit is structurally complex, both in maintenance and in restoration.

The batteries of a hybrid engine are quite sensitive to changes and temperature drops, which is why when they fall below -15 degrees Celsius, they are quickly discharged, and operation is carried out mainly on gasoline.

The high cost of the vehicle itself with a hybrid engine. Not every car enthusiast can afford a car that costs $20,000. Despite this, a number of countries have introduced preferential taxes on customs clearance, registration and use of hybrid engines to encourage buyers to buy these cars. This has not yet been done on the territory of the CIS countries.

Modern indicators

Toyota is the leader in the number of hybrids and has been actively producing these cars since 1997, and in modifications of both regular cars of the Prius series, crossovers of the Lexus RX400h series, and luxury cars - Lexus LS 600h.

In 2006, over half a million Prius models alone were sold worldwide. Toyota HSD hybrid drive technology has been licensed by Ford (Escape Hybrid), Nissan (Altima Hybrid).

Mass production of hybrid vehicles is constrained by the shortage of nickel-metal hydride batteries.

In 2006, 90,410 hybrid vehicles were sold in Japan, up 47.6% from 2005.

In 2007, sales of hybrid vehicles in the US increased by 38% compared to 2006. Hybrid vehicles in the US account for 2.15% of the new passenger car market. In total, about 350,000 hybrid vehicles were sold in the United States in 2007 (excluding GM sales).

A total of 1,002,000 hybrid vehicles were sold in the US from 1999 to the end of 2007.

Conclusion

As the current trend shows, more and more motorists are beginning to prefer hybrid powertrains. They are more economical, silent and environmentally friendly. The disadvantage of using it is expensive repairs, and the sensitivity of batteries to temperature changes.

A hybrid car (hybrid) is a vehicle that is equipped not with the usual internal combustion engine, but with the so-called hybrid power unit. The main difference between hybrid cars is that vehicles of this type are driven by the use of several energy sources: thermal and electrical. In other words, a hybrid car has several types of engines on board that power the car.

As for the very concept of a hybrid engine, this term is misunderstood by many as a special power plant. In fact, a “hybrid” should be understood as several engines of different types, which are combined into a complex single system for converting various energy sources into useful work. In modern automotive industry, hybrid cars are equipped with two types of power units: an electric motor is paired with an internal combustion engine.

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The main advantages and disadvantages of hybrid cars

One of the first developments was a scheme in which each of the power plants is activated under certain conditions. If the car is idle or the movement occurs at low speed, then the electric motor turns the wheels. To accelerate and further maintain speed, a gasoline engine is connected. The subsequent development of technology has led to the fact that on hybrids there are several options for implementing the interaction of a familiar engine and an electric motor. Such interaction can be:

consistent;
parallel;
series-parallel;

Consistent interaction

The sequential scheme resembles electric vehicles, since the movement of the vehicle is realized through the operation of an electric motor. The internal combustion engine in this design is connected to a generator, power is supplied from the generator to the electric motor itself, and the battery is also charged in parallel. On a single charge of a lithium-ion battery with increased capacity, you can often go about 50 km. way, after which the internal combustion engine is activated, which extends the specified segment up to 10 times (about 500 km.)

Parallel interaction

Hybrids with parallel interaction of installations suggest the possibility of both separate operation of the internal combustion engine and electric motor, and simultaneous operation. This design is implemented by combining with the help of special couplings of an electrical unit, an internal combustion engine and a transmission. Such hybrid vehicles receive a low-power electric motor that not only drives the car, but also gives power during acceleration. Often, such an electric motor is a starter and a car generator, structurally occupying an intermediate position between an internal combustion engine and a gearbox.

Serial-parallel communication

In this design, the internal combustion engine and the electric motor are connected by means of a planetary gearbox. A feature of this implementation scheme is that each power plant can be turned on and off, while giving a minimum or maximum of power to the wheels. Moreover, the specified power is given separately or simultaneously. In the device of such a circuit, there is a generator that feeds the electric motor of the hybrid.

The market leader in hybrid vehicles today is Toyota Corporation, which uses a series-parallel implementation called Hybrid Synergy Drive.

The electric motor, internal combustion engine and generator are combined into a common system by means of a planetary gearbox. The internal combustion engine gives a minimum of power at the "bottom" (Atkinson cycle), allowing you to save fuel. A hybrid car with such an interaction scheme assumes:

Economy mode of driving only on electric traction with the engine off, during which the electric motor is powered by the battery.
Maintaining the set speed by distributing the power of the internal combustion engine to the wheels and the generator, from which the parallel operating electric motor is powered. The battery is also recharged.
The mode of intensive acceleration and serious loads, when the internal combustion engine and the electric motor work in parallel. In this mode, the electric motor is powered by the battery, without power take-off from the generator.

Exploitation of hybrids: busting the myths

Hybrid cars are a novelty that has not been fully improved and has many flaws. This is a myth, as the Toyota brand has been in full-scale mass production of hybrid models for almost 20 years.
In hybrids, the batteries are drained, which leads to problems. This is true, but only partially. At the initial stages of technology development, such cases occurred, but today high-precision electronics do not allow deep discharge of the battery.
Hybrid cars are more likely to break down, expensive, and difficult to repair. This is a myth, as hybrid vehicles are no less reliable than conventional diesel and petrol ICEs. Most service stations comprehensively service hybrids on a par with conventional cars. Moreover, the gearbox in hybrids eliminates the presence of frictions, which makes such a transmission simple and reliable, which cannot be said about various types of automatic transmissions. As for the internal combustion engine, the engine in hybrids often works at low speeds, does not reach peak loads. If we also take into account the Atkinson cycle, then the engine life of a hybrid engine is much longer than a conventional engine.
The ICE of a hybrid has less power, such cars lose in dynamics compared to their counterparts. Yes, the power of internal combustion engines in hybrids is less, but due to the addition of an electric motor, the total power of the units significantly exceeds the power of conventional analogues with one gasoline engine.
The consumption of a hybrid car in practice is not much different from a conventional car. This is partly true, since the consumption rate of hybrid cars directly depends on the driving modes. To achieve maximum economy, it is necessary to change the driving style to slow, calm and smooth, avoiding acceleration, active throttling, etc. In other words, strong pressure on the gas pedal will instruct the control system to start the internal combustion engine.

The idea of saving fuel in hybrid cars is to drive on electric power at speeds up to 60 km/h for as long as possible with a charged battery, which is often enough in dense city traffic. It is also necessary to add that the system takes into account a large number of factors: outside temperature, the degree of heating of the internal combustion engine and, battery charge, movement downhill or on a hill, etc. Under different conditions, the hybrid can use the internal combustion engine, or it can move only on electric energy.

A hybrid battery is hard to find commercially and takes up a lot of space in the trunk of a car. This is a myth, since batteries for hybrids are always available for order in auto stores, and there is also a wide selection on various Internet resources. As for free space, the battery practically does not occupy usable space in the luggage compartment.
You can't put gas on a hybrid car. This is a myth, since global manufacturers produce equipment that is compatible with a hybrid car.

Device and principle of operation

The most common mode of operation of a hybrid engine is that when driving a car at low speed, for example, in a city, its electric unit is used. When the car moves along the highway, the internal combustion engine (ICE) is turned on. In the case of a heavy load, for example, during sharp uphill climbs, both engines are switched on.

Of course, the advantages of such a device include the fact that when using an electric motor, fuel consumption is significantly reduced, since it runs on constantly replenished battery energy.

The ability, at least in part, to reduce the amount of harmful substances emitted into the air is another plus of the car's hybrid system.

Hybrids are characterized by low power, which the internal combustion engine helps to compensate.

Hybrid engines can be either petrol or diesel. Moreover, manufacturers of natural gas equipment (LPG) have developed systems that can work on these vehicles.

An example of a hybrid design

The hybrid device includes:

Its design and dimensions are designed to reduce weight, emissions and fuel consumption.

The electric motor is developed taking into account features of a hybrid. It was made not only generated to work with a fuel block, but also paid special attention to power indicators. In parallel, it generates energy to recharge the car's battery. It can be made built into the power plant or placed separately from it, in some models both options are used at once.

Transmission. The operation of the hybrid transmission is actually the same as its arrangement on conventional cars. But, depending on the type of hybrid engine, they may differ. Gearboxes in them are either hybrid with an integrated electric motor, or conventional mechanical and automatic. For example, the transmission of a Toyota car is designed with a branching of power flows. This type of engine operates in smooth load mode, which helps to significantly save fuel consumption.

Fuel tank. Needed to fuel the internal combustion engine. To illustrate what has a number of advantages, I would like to cite one fact in favor of this: the energy obtained from the combustion of 1 liter of gasoline is comparable to the energy generated by a battery weighing about 450 kg.

Battery. Its main function is to generate a sufficient level of energy for the operation of the electric motor. The car uses two batteries, high-voltage and regular 12 (V) to power the on-board network. Initially, before the start of all systems, power comes only from the standard one, since constant cooling is necessary for the operation of the high-voltage battery and the inverter.

The inverter converts the direct current of the high-voltage battery into three-phase alternating current for the electric motor and vice versa. It also regulates the distribution of energy and controls the electric motor.

Generator. Its principle of operation is the same as that of an electric motor, but it is aimed at generating electrical energy.

3 types of hybrid units

As noted earlier, the hybrid system of a car is a combination of motors, a kind of two different crossed technologies. The hybrid drive technology is characterized in two ways - it is a dual-fuel or bivalent and a hybrid power unit.

This division into two combinations of power units is defined for their classification according to a different principle of operation.

The device of the hybrid power unit includes an internal combustion engine and an electric motor-generator. Thus, the electric motor is both an energy generator, and a traction electric motor, and a starter for starting the internal combustion engine.

There are three types of hybrid powertrain. The main criterion for classification is the execution of the main structure. Therefore, there are: a micro-hybrid power unit, a medium hybrid power unit and a full-hybrid power unit.

Micro hybrid powertrain

The conceptual feature of this type of drive is its electrical part, which is only needed to perform the start-stop function. At the same time, part of the generated kinetic energy is reused as electricity (recovery process).

The drive solely due to the operation of electric traction is not possible. The performance of the 12-volt fiberglass-filled hybrid battery is adapted to frequent engine starts. Also, a storage device in the form of an electrochemical capacitor can be used to accumulate energy from recuperation.

Micro hybrid from Mazda

Medium hybrid powertrain

The electrical drive assists the operation of the internal combustion engine. At the same time, the movement of the hybrid only due to electric traction is not carried out. With this type of hybrid motor, electrical energy is regenerated during braking and then stored in a high-voltage battery.

The device of the high-voltage battery of the hybrid and all its electrical parts meets the required voltage level, which makes it possible to generate sufficiently high power. As a result, thanks to the support of the internal combustion engine by an electric motor, its operation is characterized by maximum efficiency.

Full hybrid powertrain

The operation of two motors: an electric motor and an internal combustion engine, in this type is combined with each other. The full hybrid type allows the car to move only due to electric traction and a sufficiently long distance. Under certain conditions, the power unit functions as a medium hybrid.

These vehicles are equipped with a sufficiently powerful electric motor and high-voltage batteries of a larger volume, which allows them to produce such characteristics. The basis of battery recharging is also the process of energy recovery.

The "start-stop" function is implemented for the internal combustion engine, which starts only when necessary. And the separation of the internal combustion engine from the electric motor is carried out due to the established clutch between them, so they can function independently of each other.

Schemes of interaction between the operation of the electric motor and the internal combustion engine

Hybrid cars are designed according to three engine interaction schemes. Let's consider each of them.

Sequential scheme of interaction

This principle of the device is the simplest version of a hybrid car engine. Its operation scheme is as follows: the torque from the internal combustion engine goes to the generator. The generator then generates the electricity it needs to run and transfers it to the battery. Additionally, the battery is recharged by the process of recovery of kinetic energy. In this scheme, the movement of the car is carried out only due to electric traction.

This circuit is characterized by sequential energy conversion, i.e. the energy coming from the combustible fuel in the internal combustion engine is converted into mechanical energy, then transformed into electrical energy by a generator, and then again converted into mechanical energy.

Positive aspects of the serial scheme:

The operation of the internal combustion engine is carried out at constant speed.
There is no need for an engine with high power and fuel consumption.
A gearbox, like a clutch, is not needed here.
The electrical energy of the high-voltage hybrid battery allows the car to move with the engine turned off.

Negative sides of the serial circuit:

At the stages of energy conversion, it is lost.
The dimensions and cost of the battery are quite high.

The brightest representative of a hybrid car with a consistent scheme of interaction Chevrolet Volt

If we talk about the most suitable variant of the car movement with a sequential scheme of interaction, then this is urban traffic with frequent stops, when the energy recovery system is constantly turned on.

Parallel interaction scheme

This scheme got its name because the car engines work constantly together. The principle of operation of this type of interaction of two modules occurs due to the electronics of the car, electric motor and internal combustion engine. Both engines are connected to the gearbox by means of a planetary gear.

Purely on electric energy, such hybrids are able to drive for a short time, while the internal combustion engine is disconnected from the transmission by the clutch.

The control unit distributes the torque from both engines depending on the vehicle's driving mode. The internal combustion engine is assigned a more important role, and the electric motor starts when additional traction is needed, for example, when the car accelerates sharply. During braking or smooth movement, the electric motor works as a generator of electricity.

Electric motor integrated into BMW 530E iPerformance gearbox

There are modifications with an electric motor separate from the internal combustion engine, they are a complex system, but at the same time effective. This module consists of two electric motors, the traction motor connected via a planetary gear to the second one, which serves as a generator and starter.

In such a scheme, the internal combustion engine is not directly connected to the wheels, which allows you to constantly transfer part of the moment to the generator and recharge the battery.

Parallel hybrid powerplant with independent electric motors

Positive aspects of the parallel circuit:

Since the main work is assigned to the internal combustion engine, there is no need to install a powerful high-voltage battery. The internal combustion engine is directly connected to the drive wheels, so the energy loss is much less.

Negative sides of the parallel circuit:

The main disadvantage of this scheme is the higher fuel consumption in comparison with other engine interaction schemes. It turns out that saving on city traffic will not work, the most successful option would be to move along the highway.

Serial-parallel scheme of interaction

The very name of this circuit indicates that this type is a variant of combining the two previously considered circuits: serial and parallel. The movement of the car at low speed and its start from a place is carried out only due to the power of the electrical part. The internal combustion engine supports the operation of the auto generator, as in a sequential interaction scheme. The transfer of torque from the internal combustion engine to the wheels occurs when driving at high speed.

At high loads that require increased power, the car's generator may not produce the right amount of energy, in which case the electric motor is powered additionally from the battery, as in a parallel interaction scheme.

In this scheme, an additional generator is provided, it recharges the battery. The electric motor is only needed to drive the drive wheels and to provide regenerative braking.

Part of the torque transferred from the internal combustion engine goes to the drive wheels, and some of it goes to the generator, which in turn feeds the electric motor and charges the battery.

For the direction of the torque to the wheels, generator or electric motor and its ratio, the planetary mechanism is responsible - the power distributor. The power supply from the alternator and battery is controlled by the vehicle's electronic control unit.

This technology is also used on hybrid all-wheel drive cars. An internal combustion engine with an electric motor in a parallel circuit is installed on the front axle, and only an electric motor connected to the internal combustion engine in a serial circuit is installed on the rear axle.

All-wheel drive hybrid from Mitsubishi

Positive aspects of the series-parallel circuit:

It is not difficult to guess that the indisputable advantage of this hybrid scheme is its great fuel economy combined with good power characteristics. Nature lovers will appreciate its environmental friendliness.

Negative sides of the series-parallel circuit:

Among the negatives is a more complex design compared to previous schemes, and as a result, a high price. Since an additional generator is needed, a capacious battery and a complex electronic control circuit.

Conclusion

We have considered all types of hybrids and their interaction schemes, but in general, there are many types that are difficult to attribute to one of them, since over time technologies are more and more mixed and refined.

On some, hydraulic couplings with a gearbox are used instead of a planetary gear; on others, they experiment with a rear-mounted internal combustion engine or generally spread the internal combustion engine and electric motor along two axes. Designers do not stop there and are increasingly developing this direction.

Autoleek

How it works, consider the example of Touareg, with a hybrid powertrain.

What does the term "hybrid technology" mean?

The term "hybrid" originates from the Latin word hybrida, and means something crossed, or mixed. In engineering, a hybrid is a system in which two different technologies are combined with each other. In connection with drive concepts, the term hybrid drive technology is used to refer to two areas: bivalent (or dual-fuel) powertrain hybrid powertrain

In the case of hybrid drive technology, it is a combination of two different power units, the operation of which is based on different operating principles. Currently, hybrid drive technology means a combination of an internal combustion engine and an electric motor-generator (electric machine). This electric machine can be used as a generator to generate electrical energy, a traction motor to drive a car, and a starter to start an internal combustion engine. Depending on the execution of the main structure, three types of hybrid power unit are distinguished: the so-called. "microhybrid" power unit, the so-called. "medium hybrid" power unit, the so-called. "full hybrid" powertrain.

"Micro-hybrid" powertrain

In this drive concept, the electrical component (starter/alternator) is exclusively used to implement the start-stop function. Part of the kinetic energy can be used again as electrical energy (recuperation). Drive only from electric traction is not provided. The parameters of the 12 volt fiberglass battery are adapted to frequent engine starts.

"Medium hybrid" drive

The electric drive supports the operation of the internal combustion engine. The movement of the car only on electric traction is impossible. With a "mid-hybrid" drive, most of the kinetic energy during braking is regenerated and stored as electrical energy in a high-voltage battery. The high voltage battery as well as the electrical components are designed for higher electrical voltage and thus higher power. Thanks to the support of the electric motor-generator, the mode of operation of the heat engine can be shifted to the region of maximum efficiency. This is referred to as load point displacement.

"Full hybrid" powertrain

A powerful electric motor-generator is combined with an internal combustion engine. Only electric drive is possible. The electric motor generator, if conditions permit, supports the operation of the internal combustion engine. Movement at low speed is carried out only on electric traction. The Startstop function for the internal combustion engine has been implemented. Recovery is used to charge the high voltage battery. Thanks to the decoupling clutch between the internal combustion engine and the electric motor-generator, it is possible to ensure the separation of both systems. The internal combustion engine is connected to work only when necessary.

Fundamentals of hybrid technology

Full hybrid powertrain systems are divided into three subgroups: parallel hybrid powertrain, split powertrain (with split power flows), and series hybrid powertrain.

Parallel hybrid powertrain

Parallel execution of the hybrid power unit is simple. It is used when it is necessary to "hybridize" an existing vehicle. The internal combustion engine, electric motor generator and gearbox are located on the same axis. Typically, a parallel hybrid powertrain system uses a single electric motor/generator. The sum of the unit power of the internal combustion engine and the power of the electric motor-generator corresponds to the total power. This concept provides a high degree of borrowing components and parts of the old car. In all-wheel drive vehicles with a parallel hybrid powertrain, all four wheels are driven using a Torsen differential and a transfer case.

Separate hybrid drive

The split hybrid drive system has an electric motor generator in addition to the internal combustion engine. Both engines are located under the hood. The torque of the internal combustion engine, as well as from the electric motor-generator, is fed through the planetary gear to the vehicle gearbox. In contrast to a parallel hybrid drive, it is not possible to extract the sum of the individual powers for wheel drive in this way. The generated power is partly spent on driving the car, partly, in the form of electrical energy, accumulates in a high-voltage battery.

Series hybrid powertrain

The car is equipped with an internal combustion engine, a generator and an electric motor-generator. However, unlike both of the previously described concepts, the internal combustion engine does not have the ability to independently drive the car through a shaft, or through a gearbox. Power from the internal combustion engine is not transferred to the wheels. The main drive of the car is carried out by an electric motor generator. If the capacity of the high-voltage battery is too low, the internal combustion engine starts. The internal combustion engine charges the high-voltage battery through the generator. The electric motor generator can again be powered by the high voltage battery.

Separate sequential hybrid powertrain

The split series hybrid powertrain is a mixed form of the two hybrid drives described above. The car is equipped with one internal combustion engine and two electric motors-generators. The internal combustion engine and the first electric motor generator are located under the hood. The second electric motor generator is located on the rear axle. This concept is used for all-wheel drive vehicles. The internal combustion engine and the first electric motor generator can drive the vehicle's gearbox through a planetary gear. And in this case, the rule applies, according to which single drive powers cannot be taken for wheel drive in the form of total power. A second electric motor generator on the rear axle is activated when needed. In connection with this design of the drive, the high-voltage battery is located between both axles of the vehicle.

Other terms and definitions Other terms and definitions often used in connection with hybrid drive technology will be briefly explained here.

Recovery. In the general case, this term in technology means a way to return energy. During recuperation, the available energy of one type is converted into another, used in the subsequent type of energy. The potential chemical energy of the fuel is converted in the transmission into kinetic energy. If the car is braked by a conventional brake, then the excess kinetic energy is converted into heat energy through the friction of the brakes. The resulting heat is dissipated in the surrounding space, and therefore it is impossible to use it in the future.

If, on the contrary, as with hybrid drive technology, in addition to the classic brakes, the generator is used as an engine brake, then part of the kinetic energy is converted into electrical energy, and thus becomes available for subsequent use. The energy balance of the car is improved. This kind of regenerative braking is called regenerative braking.

As soon as the vehicle speed is reduced by decelerating by depressing the brake pedal in over idle mode, or the vehicle is coasting or the vehicle is moving downhill c The hybrid drive system includes an electric motor-generator and uses it as a generator.

In this case, it charges the high-voltage battery. So in forced idle mode
running, it becomes possible to "refuel" cars with an electric hybrid drive with electricity.
When the car is coasting, the electric motor-generator, operating in generator mode,
converts from motion energy into electrical energy only such an amount of energy that
required for the operation of the 12 volt on-board network.

Electric motor-generator (electric machine)

The term electric motor-generator, or electric machine, is used instead of the terms generator, electric motor, and starter. In principle, any electric motor can also be used as a generator. If the motor shaft is driven by an external drive, then the motor, like a generator, generates electrical energy. If electrical energy is supplied to the electric machine, then it works like an electric motor. Thus, the electric motor generator of electric hybrid vehicles replaces the conventional combustion engine starter as well as the conventional generator (lighting generator).

Electric booster (E-boost)

Similar to the kickdown function of internal combustion engines, which makes maximum engine power available, the hybrid drive features an electric E-Boost function. When using the function, the motor-generator and combustion engine deliver their maximum individual powers, which add up to a higher total power. The sum of the individual powers of both types of engines corresponds to the total power of the transmission.

Due to power losses in the electric motor-generator, its power in the generator mode is lower than in the traction motor mode. The power of the electric motor-generator in the engine mode is 34 kW. The power of the electric motor-generator in generator mode is 31 kW. In the Touareg with hybrid drive, the internal combustion engine has an output of 245 kW and the electric motor-generator has an output of 31 kW. In traction motor mode, the electric motor-generator produces 34 kW of power. Together, the internal combustion engine and the electric motor-generator in the traction motor mode develop a total power of 279 kW.

Start-stop function

The hybrid drive technology makes it possible to implement the Start-Stop function in this vehicle design. In the case of a conventional vehicle with a start-stop system, the vehicle must come to a stop in order to switch off the internal combustion engine (example: Passat BlueMotion).

However, an all-hybrid vehicle can also run on electric power. This feature allows the StartStop system to shut off the internal combustion engine when the vehicle is moving or coasting. The internal combustion engine is switched on depending on the need. This can occur when accelerating quickly, when driving at high speed, with a high load, or when the high voltage battery is very low. When the high-voltage battery is highly discharged, the hybrid drive system can use the internal combustion engine in combination with the motor generator in generator mode to charge the high-voltage battery.

In other cases, a full hybrid vehicle may run on electric power. The internal combustion engine is in stop mode. This is also true in the case of slow moving traffic, stopping at a traffic light, when driving in overrun mode downhill, or when the vehicle is coasting.

When an internal combustion engine is not running, it does not consume fuel or emit harmful substances into the atmosphere.

The start-stop function integrated into the hybrid drive system increases the vehicle's efficiency and environmental friendliness.

While the combustion engine is in stop mode, the air conditioner can continue to operate. The air conditioner compressor is an element of the high-voltage system.

Arguments in favor of hybrid technology

Why do we combine an electric motor-generator with an internal combustion engine? To take off the torque, the rotational speed of the internal combustion engine must not be lower than the idling speed. When stopped, the engine cannot deliver torque. With an increase in the rotational speed of an internal combustion engine, its torque increases. The electric motor generator with the first revolutions produces the maximum torque. It does not have an idle speed. As the speed increases, its torque decreases. Thanks to the operation of the electric motor-generator, the most difficult operating mode is excluded from the internal combustion engine: in the range below idle speed. Thanks to the support of the electric motor-generator, the internal combustion engine can be operated in more efficient modes. This displacement of the load point increases the efficiency of the power unit.

Why use a full hybrid powertrain (drive)?

The full hybrid unit, unlike other hybrid drive options, combines the function of the integrated Start-Stop system, the E-Boost system, the recuperation function and the possibility of driving only on the electric motor (electric traction mode).

Electric motor-generator

The electric motor-generator is located between the internal combustion engine and the automatic transmission. It is a three-phase synchronous motor. The power electronics module converts the 288 V DC voltage into a three-phase AC voltage. Three-phase voltage creates a three-phase electromagnetic field in the electric motor-generator.

high voltage battery

Access to the high-voltage battery is provided through the luggage compartment floor covering. It is designed as a module and includes various components of the Touareg high-voltage system. The high voltage battery module has a mass of 85 kg and can only be replaced as an assembly.

The HV battery cannot be compared with a conventional 12V battery. In normal operation, the HV battery is used in a free charge level range of 20% to 85%. A conventional 12 volt battery is unable to carry such loads for a long time. Therefore, a high-voltage battery should be considered as an operational energy storage device for an electric drive. Like a capacitor, it can store and release electrical energy again. In principle, recuperation, energy regeneration, can be considered as the possibility of refueling a car with energy while driving. The use of a high-voltage battery in a hybrid vehicle is distinguished by the alternation of charging (recovery) and discharging (electrically driven driving) cycles of the high-voltage battery.

Example: If we compare the energy of a high-voltage battery with the energy generated by burning fuel, then the amount of energy that the battery can produce will correspond to about 200 ml of fuel. This example demonstrates that on the path to electric vehicles, batteries need to be significantly upgraded in terms of their ability to store energy.

The hybrid car is not a new invention. The first step towards hybrid vehicles was taken in 1665 when Ferdinand Verbiest, a Jesuit priest, began work on plans for a simple four wheeled vehicle that could be powered by steam or horse drawn. The first cars with a hybrid engine appeared at the turn of the 19th and 20th centuries. Moreover, some developers have managed to move from projects to small-scale production. Starting in 1897 and over the next 10 years, the French Compagnie Parisienne des Voitures Electriques produced a batch of electric and hybrid cars. In 1900, General Electric designed a hybrid car with a 4-cylinder gasoline engine. And the "hybrid" trucks left the assembly line of the Walker Vehicle Company of Chicago until 1940.
Of course, all these were only prototypes and small-scale cars. Now, however, an acute shortage of oil and the economic crisis have spurred the development of hybrid engines. Now let's take a closer look at what a hybrid engine is and what is the use of it? A hybrid engine is a system of two engines - electric and gasoline. Depending on the operating modes, both petrol and electric can be switched on simultaneously or separately. This process is controlled by a powerful computer, which decides what should work right now. So, when driving along the tracks, the gasoline engine is turned on, since the battery on the track will not last long. If the car is moving in urban mode, then an electric motor is already used here, both of them work during acceleration or heavy loads. While the petrol engine is running, the battery is being charged. Such an engine, even taking into account the fact that the system uses a gasoline engine, can reduce harmful emissions into the atmosphere by 90% and at the same time, gasoline consumption in the city is significantly reduced (only a gasoline engine works on the highway, so there is no savings there).

Let's start with how the car moves off. At the beginning of the movement and at low speeds, only the battery and electric motors are involved. The energy stored in the battery goes to the energy center, which, in turn, sends it to the electric motors, making the car move smoothly and silently. After picking up speed, the internal combustion engine is connected to work, and the moment on the drive wheels is supplied simultaneously from electric motors and internal combustion engines. In this case, part of the energy of the internal combustion engine goes to the generator, and now it feeds the electric motors, and gives off the excess of its energy to the battery, which has lost part of the energy reserve at the beginning of the movement. When driving in normal mode, only front-wheel drive is automatically used, in all others - all-wheel drive. In the acceleration mode, the torque to the wheels comes mainly from the gasoline engine, and the electric motors, if necessary, increase the dynamics, complement the internal combustion engine. One of the most interesting moments is braking. The electronic “brains” of the car decide for themselves when to apply the hydraulic braking system, and when regenerative braking, giving preference to the latter. That is, at the moment the brake pedal is pressed, they transfer the electric motors to the “generator” mode of operation, and they create a braking torque on the wheels, generating electricity and feeding the battery through the energy center. This is the highlight of the “hybrid”.

In classic cars, braking energy is completely lost, leaving as heat through the brake discs and other parts. The use of braking energy is especially effective in urban areas, when you often have to brake at traffic lights. Vehicle Dynamics Integrated Management (VDIM) integrates and manages all active safety systems.
One of the first successful cars equipped with a hybrid engine that went to the masses was the Toyota Prius developed by Toyota, which consumes 3.2 liters of gasoline per 100 km (in the city). Toyota also released an SUV with a Lexus RX400h hybrid engine. The cost of such a car, depending on the configuration, ranges from 68 to 77 thousand dollars. It should be noted that the first versions of the Toyota Prius were inferior to cars of the same class both in speed and power, but the Lexus RX400h is no longer inferior to its classmates in either speed or power.

The world's leading automotive concerns have also turned their attention to hybrid engines as a solution to the problem of fuel economy and environmental pollution. So the Volvo Group announced the creation of a hybrid engine for trucks, tractors, semi-trailers and buses. The company's developers expect that their brainchild will allow you to get 35% fuel savings.
With all this, it must be said that hybrid cars "with a bang", so far, have gone only in North America (Canada and the USA). And in America, the demand for them is growing more and more, since until recent years cars that consumed a lot of fuel were popular there, and since fuel began to rise sharply and steeply in price, the Americans sharply thought about saving it and, as a solution to the problem, they began to use cars with hybrid engines. In Europe, the appearance of hybrid engines was taken calmly, since there they drive an economical and more environmentally friendly than a gasoline engine, the good old diesel. Unlike the USA, more than 50% of cars in Europe are equipped with diesel engines. In addition, diesel cars are cheaper than hybrid cars, simpler and more reliable. After all, everyone knows that the more complex the system, the less reliable it is! And precisely because of their complexity and capriciousness, there are practically no hybrid cars in the post-Soviet space. Official dealers do not bring them here. And any owner of such a car will inevitably face the problem of service stations. We do not have service stations that would deal with hybrid cars. And you can’t fix such a machine yourself!