Applications of Power Semiconductors (IGBT/MOSFET) in Electric Vehicles

Abstract: This paper provides an in-depth examination of the widespread application of power semiconductors (IGBTs and MOSFETs) in the electric vehicle sector. It elaborates on their operating principles and pivotal roles in electric vehicle powertrains, energy management systems, and charging infrastructure. By analyzing their performance characteristics and emerging trends, the study highlights the critical importance of power semiconductor technology for enhancing electric vehicle performance and driving future advancements.

Applications of Power Semiconductors (IGBT/MOSFET) in Electric Vehicles

Abstract: This paper provides an in-depth examination of the widespread application of power semiconductors (IGBTs and MOSFETs) in the electric vehicle sector. It elaborates on their operating principles and pivotal roles in electric vehicle powertrains, energy management systems, and charging infrastructure. By analyzing their performance characteristics and emerging trends, the study highlights the critical importance of power semiconductor technology for enhancing electric vehicle performance and driving future advancements.

I. Introduction
As the world increasingly prioritizes environmental protection and sustainable development, electric vehicles are rapidly emerging as a green transportation option. Power semiconductor devices—such as insulated-gate bipolar transistors (IGBTs) and metal–oxide–semiconductor field-effect transistors (MOSFETs)—are critical components that enable efficient power conversion and control in electric vehicles, playing a decisive role in their performance, efficiency, and reliability.

II. Basic Principles and Characteristics of IGBTs and MOSFETs

(1) Principles and Characteristics of IGBTs

An IGBT is a device that combines the characteristics of a MOSFET and a bipolar transistor. It offers advantages such as high input impedance, low drive power, low on-state resistance, and high blocking voltage. In the on-state, it exhibits a low forward voltage drop and can handle substantial current; in the off-state, its leakage current is extremely small.

(II) Principles and Characteristics of MOSFETs

MOSFETs are unipolar devices that rely on majority carriers for conduction. They offer advantages such as fast switching speeds, extremely high input impedance, and excellent thermal stability. However, in high-voltage, high-current applications, their on-state resistance remains relatively large.

III. Applications in Electric Vehicle Powertrains

(1) Motor Drive

The electric vehicle’s motor drive system must convert the battery’s DC power into AC power to operate the motor. Inverters composed of IGBTs and MOSFETs play a crucial role in this process. By switching at high frequencies, they modulate the DC voltage into the desired AC waveform, enabling precise control of the motor’s speed and torque.
For example, in high-performance electric vehicles, the use of advanced IGBT modules enables rapid response to control signals, ensuring efficient motor operation and delivering robust power output.

(2) Regenerative Braking

During braking, the motor can operate as a generator, converting the vehicle’s kinetic energy into electrical energy and feeding it back into the battery. Power semiconductor devices manage the direction of power flow and optimize conversion efficiency, enhancing energy recovery and extending the vehicle’s range.

IV. Applications in Electric Vehicle Energy Management Systems

(1) Battery Management

Power semiconductors are used to control battery charging and discharging, ensuring that the battery operates within safe voltage and current limits and extending its service life. At the same time, they also play a crucial role in balancing the state of charge among individual cells in a battery pack.

(2) DC/DC Conversion

Electric vehicles feature subsystems operating at different voltage levels, such as the high-voltage traction battery and low-voltage onboard electronic devices. IGBTs and MOSFETs can be employed in DC/DC converters to achieve efficient power conversion between these voltage levels.

V. Applications in Electric Vehicle Charging Systems

(1) In-vehicle charger

The vehicle-mounted charger converts AC mains power into DC to charge the battery. MOSFETs are commonly used in the front-end power factor correction circuit to improve charging efficiency and reduce harmonic distortion on the grid. Meanwhile, IGBTs are employed in the rear-end DC‑DC conversion stage to deliver stable output voltage and current.

(2) DC Fast Charging Piles

DC fast-charging stations must deliver substantial amounts of electrical energy to electric vehicles within a short time. Thanks to their ability to withstand high voltages and large currents, IGBT modules are widely used in the power conversion circuits of these stations, significantly reducing charging times.

VI. Performance Requirements and Challenges

(1) High voltage withstand capability and high current handling capacity

To meet the high-power requirements of electric vehicles, power semiconductor devices must exhibit higher voltage ratings and greater current-carrying capability.

(2) Low conduction losses and switching losses

Reducing losses helps improve the energy efficiency of electric vehicles and extend their driving range.

(3) High-Temperature Resistance and Reliability

Automotive operating environments are complex, requiring power semiconductor devices to function reliably under harsh conditions such as high temperatures and vibration.

VII. Development Trends

(1) Applications of Wide-Bandgap Semiconductor Materials

Wide-bandgap semiconductor materials such as silicon carbide (SiC) and gallium nitride (GaN) exhibit superior electrical properties, enabling significant increases in the operating frequency of power semiconductor devices while reducing on-state resistance and switching losses, thereby enhancing the performance and efficiency of electric vehicles.

(II) Integration and Modularization

Integrating multiple power semiconductor devices and drive circuits into a single module reduces system size, enhances reliability, and lowers costs.

(3) Intelligent Control

By leveraging smart sensors and advanced algorithms, real-time monitoring and precise control of power semiconductor devices are enabled, thereby optimizing the operational performance and reliability of electric vehicles.

VIII. Conclusion
Power semiconductors (IGBTs and MOSFETs) play an indispensable role in the key systems of electric vehicles. As technology continues to advance, they will face increasingly stringent performance requirements and new opportunities for development. Looking ahead, through the adoption of advanced materials, greater integration, and intelligent innovations, power semiconductors will deliver more efficient, reliable, and user‑friendly energy conversion and control solutions, thereby driving the sustained and rapid growth of the electric vehicle industry.