Mechanism and Applications of Automotive Inverters in Electric Vehicles
With several countries aiming to minimize their carbon footprint by 2030, limiting the sales of conventional internal combustion engine (ICE) vehicles and pushing the growth of electric vehicles (EVs) is an evident step toward a sustainable future.
Several policies, such as establishing EV car manufacturing and its battery charging standards, encouraging the implementation of EV charging infrastructure, and rolling out publicly accessible chargers, both within and outside the city network, are also impacting the global adoption of electric transportation.
As the demand for electric vehicles is increasing, the demand for its essential components, such as automotive inverters, is also increasing. Due to various innovations and technological advancements in the automotive industry, the global automotive inverter market is growing rapidly, thereby paving the way for alternative energy vehicles such as battery electric vehicles (BEVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs).
According to the BIS Research market report, the global automotive inverter market was estimated to be at $8.3 billion in 2020, which is expected to grow with a CAGR of 17.09% and reach $50.1 billion by 2031.
Functions of Automotive Inverter in an Electric Vehicle
An inverter is an electrical device that converts electricity derived from a direct current (DC) source to an alternating current (AC) of the type that can be used to drive a device or appliance. An automotive inverter serves the same purpose in a hybrid or battery EV car. It is one of the most important functioning components of any electric vehicle.
The DC power from a battery is transferred to the primary winding in a transformer within the inverter. Through an electronic switch (generally a set of semiconductor transistors), the direction of the flow of current is continuously and regularly flip-flopped (the forward and backward flow of electrical charge into the primary winding). Further, the inflow and outflow of electricity produce AC power in the transformer’s secondary winding circuit. Ultimately, this induced alternating current provides power for an AC load in an electric vehicle’s electric traction motor.
Applications of Automotive Inverters in Electric Vehicles
The following are the applications of automotive inverters across different types of electric vehicles:
1. Battery Electric Vehicles: BEVs operate only on stored electricity with the use of a battery that converts chemical energy stored in a rechargeable battery into electrical energy to drive the vehicles. The automotive inverter is the device that converts DC power stored in the battery to the AC power used in an EV motor. The inverter can change the speed at which the motor rotates by adjusting the frequency of the alternating current. It can also increase or decrease the power or torque (a force that tends to cause rotation) of the motor by adjusting the amplitude of the signal.
Pure EVs generate constant and high torque because of an electric motor that is capable of producing a uniform torque over a broad range of speeds from zero km/h. The acceleration obtained in the case of BEVs is much larger than that in conventional vehicles.
The battery packs are generally preferred to be made up of lithium-ion cells, owing to their high charge density property. They can be recharged by plugging the vehicle into an electric power source. BEVs consist of one or more electric motors, a high voltage battery, and a controller to manage power electronics.
An EV has many advantages, such as zero toxic emission, the potential for zero carbon dioxide, lower maintenance and running costs, and high energy efficiency. However, some drawbacks include less driving range, high battery costs, and recharging time.
2. Hybrid Electric Vehicles: HEVs combine an internal combustion engine and an electric motor consuming energy from a rechargeable battery. Although, in HEVs, users do not have to plug their vehicles into an electric power source to charge. The battery is fully charged through regenerative braking, which supports and strengthens the ICE during acceleration.
The principle behind regenerative braking is whenever the driver applies the brake pedal, heat dissipates, and the kinetic energy of the moving vehicle is converted into mechanical energy.
The inverter drives the electric motor, captures energy released through regenerative braking, and feeds this back to the battery. It is designed to minimize switching losses and maximize thermal efficiency.
As a result, the range of the vehicle is directly related to the efficiency of the automotive inverter. Within an electric vehicle, the inverter controls the electric motor.
This is a key component in the car, similar to the engine management system used in combustion vehicles, as it determines the driving behavior.
There are two types of hybrids available, namely, mild hybrids and full hybrids.
3. Mild hybrids are unable to power the vehicle using only electricity. In contrast, full hybrids possess larger batteries, which enables them to power the vehicles using only batteries for short distances and at lower speeds.
Since HEV has both an IC engine and a battery, high-temperature heat generated by the IC engine tends to decrease the battery’s performance. Therefore, the battery needs special attention from adhesive and sealant manufacturers to prevent thermal runaways for better thermal management. Examples of hybrid vehicles are Toyota Prius, Toyota Yaris, Toyota Camry Hybrid, Ford Escape Hybrid, Ford Fusion Hybrid, Honda Insight, Honda Civic Hybrid, and Lexus RX 400h. As per the government guidelines, HEVs with no carbon emissions would be allowed to be available until 2035.
Conclusion
Automotive inverters are one of the most important components of electric vehicles. Hence, a great deal of investment and advances in battery and inverter technology are being carried out by manufacturers to increase the range of electric vehicles.
The prices of the vehicles are predicted to drop once when these technologies and materials reach their optimal level of functioning, thereby allowing for their widespread use. As the automobile inverter is an essential component of an alternative energy vehicle, demand from both OEMs and aftermarket suppliers is likely to rise, causing significant changes in the automotive industry.
