With LG, one of the suppliers of electric car components, we review three of the most important ones: the engine, the inverter, and the charger.
The electrification of the car requires a series of specific components that, in many cases, and as in the case of combustion vehicles, reach the production lines of manufacturers supplied by third parties. To reduce the manufacturing costs of the electric car, components such as the engine, inverter or onboard charger are used in different models from different manufacturers, as they do not need to be physically adapted to space they will occupy inside the vehicle. On the other hand, it may be necessary to adapt the electronics and the software that manages them.
LG is one of the companies that manufactures specific components for the powertrain of an electric car. For example, all the components of the Chevrolet Bolt come from LG, including the battery, which is not discussed here, and which in this case is supplied by LG Chem, the Korean manufacturer’s specialist division in this component.
The traction motor
The electric motor converts the electrical energy stored in the high voltage battery into mechanical rotation energy. In the case of LG, the technology used is that of permanent magnets. It is a synchronous AC motor in which the magnetic field of the rotor is created using permanent neodymium magnets or other rare earth. These types of motors, the most commonly used in industry, are very compact and simple but have the disadvantage that they require very expensive materials for their manufacture, such as the rare earth mentioned above.
LG offers motors with a rated output power between 80 and 145 kW (107-195 hp) and an efficiency of 96%.
This component is responsible for converting the direct current coming from the traction battery into the alternating current required by the motor for its operation. In addition, the electronics that incorporates, controls, the intensity, and frequency of energy output, varying the speed at which the motor turns and the power, according to the demand of the driver at any given time.
The LG inverter supports a maximum output power of 120 kW with an efficiency of 97%. It incorporates a short-circuit protection function and a direct water cooling system that increases its reliability.
In electric vehicles, this is an essential component, as it is responsible for governing the charging process when we do not use a fast charging point. In these, when the charge is made in direct current, it is the station itself that manages the process.
At the connected recharging points – those installed in homes – or at public recharging points – also known as opportunity recharging points – the charger takes the energy from the grid (in alternating current) and inserts it into the battery (in direct current), for which purpose it needs to use a rectifier, which works the other way round than an inverter. The charging speed of the electric car depends on it and on the maximum power of the installation.
LG offers up to 11 kW of recharging power in a three-phase alternating current, with 95% efficiency, in its chargers. In single-phase current its load power varies between 3.3 kW and 6.6 kW.
Today, most brands are electrifying their portfolio of combustion engines with 48-volt hybrid systems to reduce emissions and increase the efficiency of fuel-powered engines. So-called light or soft hybrids use a 48-volt alternator to recover energy during deceleration and store it in a small battery of the same voltage. This small electric motor is linked to the timing belts of the combustion engine to assist in propulsion and allow the engine to be kept off at certain times for short periods of time.
The 48-volt LG alternator, called the Belt-Integrated Starter Generator (B-ISG), operates either water-cooled or air-cooled and develops power ratings of between 11 and 33 kW, with 95% efficiency.