The current F1 hybrid engine consists of 5 main parts:
- The internal combustion engine (ICE)
- The turbo ( consisting of a compressor and a turbine)
- The MGU-H
- The MGU-K
- The energy store
Each part has a vital part to play in ensuring the engine is powerful, reliable and efficient. Below is a more detailed description of how each part of the engine works.
The internal combustion engine is much smaller than the 2.4 litre V8 engines used previously. The engine is a small 1.6 litre V6, however it is capable of producing over 600 horsepower. These small engines are similar in size to many road cars but are more powerful. However producing this amount of power for companies such as Ferrari isn’t a big challenge. The biggest challenge regarding the ICE is the high pressures. With a turbo-charger, the pressures within the combustion chamber are almost double what they were before. The engines must be designed well in order to prevent the pressure from becoming destructive.
Direct fuel injection is used in all engines – meaning the fuel is sprayed straight into the combustion chamber rather than into the inlet port. This means that the fuel-air mixture is made within the combustion chamber instead of before entering it. It has the benefit of measuring the fuel more precisely, allowing more complete combustion and therefore greater fuel efficiency – an important factor as the rules only allow 100kg of fuel per race.
The turbocharger uses the energy of the exhaust gases in order to increase the pressure of the air which enters the engine. This, therefore, allows a smaller engine to produce a greater amount of power. The turbo is made up of 2 parts:
- Turbine – The turbine is rotated by the exhaust gasses. This turbine is connected to the compressor by a shaft.
- Compressor – The compressor then uses the power made from the turbine in order to increase the pressure of the air entering the engine.
The turbo spins extremely fast – up to 100,000 rpm. This means that a huge amount of pressure is generated but also a lot of heat. This heat is then converted into electrical energy by the MGU-H.
A challenge faced by the manufacturers is turbo lag, this is due to the fact the turbocharger’s speed must alter depending on the engine’s requirements. It becomes an issue when the car has been going slowly, under braking, and then the driver comes onto the throttle. The torque response may be delayed slightly, the aim is to reduce turbo lag as much as possible.
The MGU-H is connected to the turbo and converts the heat into electrical energy. This energy can the be stored in the energy store or used to power the MGU-K. The energy recovered from this system is unlimited by the regulations.
Another use of the MGU-H is to control the speed of the turbo. This means that it also helps to reduce turbo-lag as well as creating electrical energy.
The MGU-K works in the same way as the KERS system used to work. It is attached to the crankshaft of the engine and then under braking it recovers some of the kinetic energy. It then converts this into electricity which can be used as a boost during the lap. The amount of energy which can be deployed per lap is 160BHP. Under acceleration, this unit is powered by the MGU-H or energy store.
The energy store is effectively just a battery, where the energy generated by the MGU-H and MGU-K can be stored. It can be used to power the MGU-K or to accelerate the turbo with the MGU-H – to reduce turbo lag. The battery has a minimum weight of 20kg.