hybrid time

In a situation where it is difficult to put all the money on purely electric vehicles, if only because of the still unsatisfactory range, battery imperfections, troublesome long charging and environmental conscience worries, hybrid solutions become a reasonable golden mean. This can be seen in the results of car sales.

Hybrid car this vehicle in a typical system equipped engine and one or more (1). The electric drive can be used not only to reduce fuel consumption, but also to increase power. Modern hybrid cars use additional methods to improve energy efficiency, such as. In some implementations, an internal combustion engine is used to generate electricity to power an electric motor.

1. Diagram of a diesel-electric hybrid vehicle

In many hybrid designs exhaust emissions it is also reduced by turning off the internal combustion engine when parked and turning it back on when needed. Designers strive to ensure that the interaction with the electric motor optimizes its operation, for example, when an internal combustion engine is running at low speeds, its efficiency is low, since it requires the most energy to overcome its own resistance. In a hybrid system, this reserve can be used by increasing the speed of the internal combustion engine to a level suitable for charging the battery.

Almost as old as cars

The history of automobile hybrids usually begins in 1900, when Ferdinand Porsche presented the model at the World Exhibition in Paris. Gibrid Lohner-Porsche Mixte (2), the world's first diesel-electric hybrid vehicle. Several hundred copies of this machine were later sold. Two years later, Knight Neftal built a hybrid racing car. In 1905, Henri Pieper introduced a hybrid in which an electric motor could charge batteries.

In 1915, the Woods Motor Vehicle Company, a manufacturer of electric vehicles, created the Dual Power model with a 4-cylinder internal combustion engine and an electric motor. Below a speed of 24 km / h, the car worked only on the electric motor until until the battery runs outand above this speed, the internal combustion engine was turned on, which could accelerate the car to 56 km / h. Dual Power was a commercial failure. It was too slow for its price and too difficult to drive.

In 1931, Erich Geichen proposed a car whose batteries were charged while descending a hill. Energy was supplied from a cylinder of compressed air, which was pumped thanks to kinetic energy car parts going downhill.

Senergy recovery during braking, a key invention of modern hybrid technology, was developed in 1967 by AMC for American Motors and named the Energy Regeneration Brake.

In 1989, Audi released the experimental car Audi Duo. It was in parallel hybrid based on the Audi 100 Avant Quattro. The car was equipped with a 12,8 hp electric motor that drove the rear axle. He drew energy from nickel cadmium battery. The front axle was driven by a 2,3-liter five-cylinder petrol engine with 136 hp. Audi's intention was to create a car that would be powered by an internal combustion engine outside the city and an electric motor in the city. The driver has selected combustion mode or electric driving mode. Audi produced only ten copies of this model. Low customer interest was attributed to lower performance than the standard Audi 100 due to the extra workload.

The breakthrough came from the Far East

The date from which hybrid cars entered the market widely and gained real popularity is only 1997, when it entered the Japanese market. Toyota Prius (3). Initially, these cars found buyers mainly in environmentally sensitive circles. The situation changed in the next decade, when oil prices began to rise rapidly. Since the second half of the last decade, other manufacturers have also begun to bring to market hybrid models, often based on licensed Toyota hybrid solutions. In Poland, Prius appeared in showrooms in 2004. In the same year, the second generation of the Prius was released, and in 2009, the third.

She followed Toyota Honda, another Japanese automotive giant. model sale Insight (4), a partial parallel hybrid, the company launched in 1999 in the US and Japan. It was a more economical car than a Toyota product. The first generation Prius sedan consumed 4,5 l/100 km in the city and 5,2 l/100 km outside the city. Two-wheeled Honda Insight The first generation consumed 3,9 l / 100 km in the city and 3,5 l / 100 km outside the city.

Toyota released new hybrid versions of cars. Production Toyota Auris Hybrid started in May 2010. It was the first production hybrid in Europe to sell for less than the Prius. Auris Hybrid it had the same drive as the Prius, but the gas mileage was less - 3,8 l / 100 km on the combined cycle.

By May 2007, Toyota Motor Corporation had sold its first million hybrids. Two million by August 2009, 6 million by December 2013. In July 2015, the total number of Toyota hybrids exceeded 8 million. In October 2015, sales of Toyota hybrids in Europe alone exceeded one million units. In the first quarter of 2019, hybrids already accounted for 50 percent. total sales of Toyota on our continent. Most popular models in this category, however, there are no more Priuses, but consistently Yaris Hybrid, C-HR Hybrid Oraz Corolla Hybrid. By the end of 2020, Toyota intends to sell 15 million hybrids, which, according to the company, was done in January this year, i.e. at the beginning. Already in 2017, according to the manufacturer, 85 million tons were emitted into the atmosphere. carbon dioxide downward.

During a mainstream career spanning more than two decades automotive hybrids new innovations have emerged. Hybrid Hyundai Elantra LPI (5), which went on sale in South Korea in July 2009, was the first internal combustion engine hybrid powered by LPG. Elantra is a partial hybrid that uses lithium polymer batteries, also for the first time. The Elantra consumed 5,6 liters of gasoline per 100 km and emitted 99 g/km of COXNUMX.₂. In 2012, Peugeot came up with a new solution with the launch of the 3008 Hybrid4 for the European market, the first mass-produced diesel hybrid. According to the manufacturer, the 3008 Hybrid van consumed 3,8 l/100 km of diesel fuel and emitted 99 g/km of CO.₂.

5. Hybrid Hyundai Elantra LPI

The model was presented at the New York International Auto Show in 2010. Lincoln MKZ Hybrid, the first hybrid version to be priced identically to the regular version of the same model.

By April 2020, since the landmark year 1997, more than 17 million hybrid electric vehicles had been sold worldwide. The market leader is Japan, which sold more than 2018 million hybrid vehicles by March 7,5, followed by the US, which sold a total of 2019 million units by 5,4, and 2020 million hybrid vehicles sold in Europe by July 3. The best-known examples of widely available hybrids are, in addition to the Prius, hybrid versions of other Toyota models: Auris, Yaris, Camry and Highlander, Honda Insight, Lexus GS450h, Chevrolet Volt, Opel Ampera, Nissan Altima Hybrid.

Parallel, series and mixed

Several different genera are currently hidden under the generic name "hybrid". propulsion systems and ideas for greater efficiency. It must be remembered that now, as the design develops and advances, clear classifications sometimes fail, because combinations of various solutions are used plus new inventions that violate the purity of the definition. Let's start by dividing by drive configuration.

W hybrid drive parallel type internal combustion engine and electric motor are mechanically connected to the drive wheels. A car may be powered by an internal combustion engine, an electric motor, or both. This scheme is used in Honda cars: Insight, Civic, Accord. Another example of such a system is the General Motors belt alternator/starter on the Chevrolet Malibu. In many models, the internal combustion engine also works as power generator.

Parallel drives currently known on the market consist of full power internal combustion engines and smaller (up to 20 kW) electric motors, as well as small batteries. In these designs, the electric motors only need to support the main engine and not be the main power source. Parallel hybrid drives are considered more efficient than systems based only on internal combustion engines of the same size, especially in city and highway driving.

In a sequential hybrid system, the vehicle is driven directly by an electric motor only, and an internal combustion engine is used to propel the system. electric current generator as well as. The set of batteries in this system is usually much larger, which affects the production costs. This arrangement is believed to increase the efficiency of the internal combustion engine, especially when driving in the city. Example serial hybrid This is a Nissan e-Power.

Mixed hybrid drive combines the advantages of both of the above solutions - parallel and serial. These "hybrid hybrids" are considered optimal in terms of performance, compared to series, which are most efficient at low speeds, and parallel, which are optimal at higher speeds. However, their production as more complex circuits is more expensive than parallel motors. The dominant manufacturer of mixed hybrid powertrains is Toyota. They are used in Toyota and Lexus, Nissan and Mazda (mostly under license from Toyota), Ford and General Motors.

Power from two internal combustion engines and a parallel one can be transferred to the wheel drive using a device of the type (power distributor), which is a simple set of planetary gears. Internal combustion engine shaft connected to the fork of the planetary gears of the gearbox, the electric generator - with its central gear, and the electric motor through the gearbox - with the external gear, from which the torque is transmitted to the wheels. This allows you to transfer part rotational speed and the torque of the internal combustion engine to the wheels and part to the generator. Thereby engine it can operate within the optimal RPM range regardless of vehicle speed, for example when starting off, and the current generated by the alternator is used to power the electric motor, whose high torque is maintained by the internal combustion engine to drive the wheels. The computer, which coordinates the operation of the entire system, regulates the load on the generator and the power supply to the electric motor, thereby controlling the operation of the planetary gearbox as electromechanical continuously variable transmission. During deceleration and braking, the electric motor acts as a generator to recharge the battery, and when starting the internal combustion engine, the generator acts as a generator. starter.

W full hybrid drive the car can be powered either by the engine alone, or by the battery alone, or both. Examples of such a system are Hybrid Synergy Drive Toyota, hybrid system ship, Dual mode hybrid production General Motors / ChryslVehicle examples: Toyota Prius, Toyota Auris Hybrid, Ford Escape Hybrid, and Lexus RX400h, RX450h, GS450h, LS600h and CT200h. These cars require large, efficient batteries. By using a power sharing mechanism, vehicles gain more flexibility at the cost of increased system complexity.

partial hybrid in principle, this is a conventional car with an extended starter, allowing the internal combustion engine to be turned off every time the car goes downhill, to brake or stop, and to quickly start the engine if necessary.

Starter it is usually installed between the engine and transmission, replacing the torque converter. Provides additional energy when ignited. Accessories such as radio and air conditioning can be turned on when the combustion engine is not running. Batteries are charged when braking. Compared to full hybrids partial hybrids have smaller batteries and a smaller electric motor. Therefore, their empty weight and their production cost are lower. An example of this design was the full-size Chevrolet Silverado Hybrid, produced in 2005-2007. He saved up to 10 percent. when switching off and on the internal combustion engine and recuperation of energy during braking.

Hybrids of hybrids and electrics

Another category of hybrids should be given more time, which in some ways is another step towards “pure electrics”. These are hybrid vehicles (PHEVs) in which the batteries for electric drive can also be charged from an external source (6). Thus, PHEV can be considered a hybrid of a hybrid and an electric vehicle. It is equipped charging plug. As a result, the batteries are also several times larger, which means that it is possible to install a more powerful electric motor.

6. Diagram of a hybrid car

As a result, hybrid cars consume less fuel than classic hybrids, can typically run about 50-60 km "on current" without starting the engine, and also have better performance, because hybrids are often the most powerful options. this model.

The range of a PHEV electric vehicle is many times greater than that of a hybrid vehicle without this feature. These few tens of kilometers are quite enough for trips around the city, to work or to the store. For example, in Skoda Superb iV (7) The battery can store up to 13 kWh of electricity, which provides a range of up to 62 km in zero emission mode. Thanks to this, when we park our hybrid at home and return home, we can achieve an average fuel consumption of 0 l/100 km. The internal combustion engine protects the battery from discharging in a place where there is no access to a power source, and, of course, allows you not to worry about the range on long trips.

7. Skoda Superb iV hybrid during charging

equally important type hybrids equipped with powerful electric motors Skoda Superb iV its parameters are 116 hp. and 330 Nm of torque. Thanks to this, the car not only accelerates immediately (the electric motor drives the car just as fast, no matter what speed it is running at the moment), because Skoda reports that the Superb accelerates to 60 km / h in 5 seconds, it can also accelerate the car to 140 km/h – this allows you to drive stress-free and in zero-emission mode, for example on ring roads or motorways.

While driving, the car is usually powered by both engines (the internal combustion engine is powered by electricity, so it uses less fuel than in a conventional car), but when you release the gas, brake or drive at a constant speed, the internal combustion engine shuts off the engine and only after electric motor drives wheels. So the machine works just like classic hybrid and restores energy in the same way - with each braking, energy is restored and goes to the batteries in the form of electric current; in the future, it serves precisely to ensure that the internal combustion engine can be switched off more often.

The first plug-in hybrid vehicle was launched on the market by Chinese manufacturer BYD Auto in December 2008. It was the F3DM PHEV-62 model. Premiere of the plug-in hybrid version of the most popular electric car in the world, Chevrolet Volttook place in 2010. T.oyota premiered in 2012.

While not all models operate in the same way, most can operate in two or more modes: "all electric" where the engine and battery provide all the energy for the car, and "hybrid" which uses both electricity and gasoline. PHEVs typically operate in all-electric mode, running on electricity until the battery runs out. Some models switch to hybrid mode after reaching a target speed on the highway, usually around 100 km/h.

Apart from the Skoda Superb iV described above, the most famous and popular hybrid models are Kia Niro PHEV, Hyundai Ioniq Plug-in, BMW 530e and X5 xDrive45e, Mercedes E 300 ei E 300 de, Volvo XC60 Recharge, Ford Kuga PHEV, Audi Q5 TFSI e, Porsche Cayenne E-Hybrid.

Hybrids from the depths of the sea to the skies

It is worth remembering that hybrid drive used not only in the segment of passenger cars and cars in general. for example hybrid drive systems use diesel engines Or turboelectric to power railway locomotives, buses, trucks, mobile hydraulic machines and ships.

In large structures, it usually looks like this diesel/turbine engine drives an electric generator or hydraulic pumpwhich drives an electric/hydraulic motor. In larger vehicles, relative power loss is reduced and the benefits of distributing power through cables or pipes rather than mechanical components become more apparent, especially when power is transferred to multiple drive systems such as wheels or propellers. Until recently, heavy vehicles had a small supply of secondary energy, such as hydraulic accumulators / accumulators.

Some of the oldest hybrid designs were non-nuclear submarine drivesrunning on raw diesels and underwater batteries. For example, World War II submarines used both serial and parallel systems.

Less well-known, but no less interesting designs are fuel-hydraulic hybrids. In 1978, students at the Minnesota Hennepin Vocational and Technical Center in Minneapolis converted a Volkswagen Beetle into petrol-hydraulic hybrid with finished parts. In the 90s, American engineers from the EPA laboratory developed a "petro-hydraulic" transmission for a typical American sedan.

The test car reached a speed of about 130 km / h in a mixed urban and highway driving cycles. Acceleration from 0 to 100 km / h was 8 seconds using a 1,9 liter diesel engine. The EPA estimated that the mass-produced hydraulic components added just $700 to the price of the car. EPA testing tested the Ford Expedition's petrol-hydraulic hybrid design, which consumed 7,4 liters of fuel per 100 kilometers in city traffic. The US courier company UPS currently operates two trucks using this technology (8).

8. Hydraulic hybrid in the service of UPS

The US military has been testing Humvee hybrid SUVs since 1985. The evaluations noted not only greater dynamics and greater fuel economy, but also, for example, a smaller thermal signature and quieter operation of these machines, which, as you might guess, can be of great importance in military applications.

Early form hybrid propulsion system for maritime transport there were ships with sails on the masts and Steam engines below deck. Another example has already been mentioned diesel-electric submarine. Newer, though again old-fashioned, hybrid propulsion systems for ships include, among others, large kites from companies such as SkySails. Towing kites they can fly at altitudes several times higher than the highest ship masts, intercepting stronger and more steady winds.

Hybrid concepts have finally found their way into aviation. For example, the prototype aircraft (9) was equipped with a hybrid exchangeable membrane system (PEM) up to motor power supplywhich is connected to a conventional propeller. The fuel cell provides all the power for the cruise phase. During takeoff and climb, the most power-demanding segment of flight, the system uses lightweight lithium-ion batteries. The demonstration aircraft is also the Dimona motor glider, built by the Austrian company Diamond Aircraft Industries, which carried out modifications to the design of the aircraft. With a wingspan of 16,3 meters, the aircraft will be able to fly at a speed of about 100 km / h, using the energy received from the fuel cell.

9 Boeing Fuel Cell Demonstrator Aircraft

Not everything is pink

It is undeniable that, due to the complexity of the design of hybrid vehicles than in the case of conventional vehicles, the reduction in vehicle emissions more than compensates for these emissions. Hybrid vehicles can cut emissions of smog-causing pollutants by up to 90 percent. and cut carbon emissions in half.

Despite the fact that Hybrid car consume less fuel than conventional cars, there is still a concern about the environmental impact of the hybrid car battery. Most hybrid car batteries today fall into one of two types: nickel-metal hydride or lithium-ion. However, both are still considered more environmentally friendly than lead batteries, which currently make up the majority of starter batteries in gasoline vehicles.

It should be noted here that the data is not unambiguous. General toxicity and environmental exposure levels nickel hydride batteries considered to be much lower than in the case lead acid batteries or using cadmium. Other sources say that nickel-metal hydride batteries are much more toxic than lead-acid batteries, and that recycling and safe disposal are much more burdensome. Various soluble and insoluble nickel compounds, such as nickel chloride and nickel oxide, have been shown to have well-known carcinogenic effects confirmed in animal experiments.

Batteries litowo-jonowe They are now considered an attractive alternative because they have the highest energy density of any battery and can produce more than three times the voltage of NiMH battery cells while maintaining high volumes. Electric energy. These batteries also produce more power and are more efficient, avoiding wasted power to a greater extent and providing superior durability, with battery life approaching that of a car. In addition, the use of lithium-ion batteries reduces the overall weight of the car, and also allows you to get 30 percent. improved fuel economy than gasoline-powered vehicles, with subsequent reduction in CO emissions₂.

Unfortunately, the technologies under consideration are destined to depend on hard-to-find and more expensive materials. Down motor design and other parts of hybrid vehicles need, among other things, rare earth metals. for example dysprosium, a rare earth element required for the production of various types of advanced electric motors and battery systems in hybrid propulsion systems. Or neodymium, another rare earth metal that is a key component of high-strength magnets used in permanent magnet electric motors.

Almost all rare earths in the world come mainly from China. Several non-Chinese sources such as Hoidas Lake in northern Canada or Mount Veld in Australia it is currently under development. If we do not find alternative solutions, whether in the form of new deposits or materials that will replace rare metals, then there will certainly be an increase in the prices of materials. And this could derail plans to reduce emissions by gradually phasing out gasoline from the market.

There are also problems, besides the rise in prices, of an ethical nature. In 2017, a UN report revealed abuses children in cobalt mines, an extremely important raw material for our green technologies, including the latest generation of electric motors in the Democratic Republic of the Congo (DCR). The world has learned about children who were forced to work in the dirty, dangerous and often toxic cobalt mines as early as the age of four. The United Nations estimates that about eighty children die in these mines every year. Up to 40 minors were forced to work daily. Sometimes that's the dirty price of our pure hybrids.

Exhaust pipe innovations are encouraging

However, there is good news for hybrid methods and a general desire for cleaner cars. Researchers have recently developed a promising and surprising simple modification of diesel engineswhich can be combined with electric drive in hybrid systems. Diesel drives this can make them smaller, cheaper, and easier to maintain. And most importantly, they will be cleaner.

Charles Mueller and three of his colleagues at the Sandia National Laboratory research center were working on a modification known as Channel Fuel Injection (DFI-). It is based on the simple principle of a Bunsen burner. Scientists say DFI can reduce exhaust emissions and the DPF's tendency to clog soot. According to Muller, his invention could even extend oil change intervals by reducing the amount of soot in the crankcase.

So how does it work? Nozzles in conventional diesel they create rich mixtures in the combustion chamber areas. However, according to scientists, these areas contain from two to ten times more fuel than is necessary for its complete combustion. With such an excess of fuel at high temperature, there should be a tendency to form a large amount of soot. The installation of DFI ducts allows efficient combustion of diesel fuel with little or no soot formation. “Our mixtures contain less fuel,” explains Müller in a publication about the new technology.

The channels Mr. Muller is talking about are tubes installed a short distance from where they exit the nozzle holes. They are mounted on the underside of the cylinder head next to the injector. Müller believes they will eventually be made from a high temperature resistant alloy to withstand the heat energy of combustion. However, according to him, the additional costs associated with the implementation of the invention developed by his team will be small.

When a combustion system produces less soot, it can be used more efficiently. exhaust gas recirculation system (EGR) to reduce nitrogen oxides, NOx. According to the developers of the solution, this could reduce the amount of soot and NOx coming out of the engine to one tenth of the current level. They also note that their concept will help reduce CO emissions.₂ and other substances that cause global warming.

The above is not only a signal that, perhaps, we will not say goodbye to diesel engines so quickly, on which many have already given up. Innovations in combustion drive technology are a continuation of the thinking behind the growing popularity of hybrids. It is a strategy of small steps, gradually reducing the burden on the environment from vehicles. It's nice to know that innovations in this direction appear not only in the electrical part of the hybrid, but also in the fuel.