With the rise of SiC power devices, new energy vehicles are experiencing a performance revolution!

With the rapid development of the new energy vehicle industry, power electronics technology plays an increasingly important role in it. In particular, power semiconductor devices, as core components of power conversion and circuit control, have a direct impact on the energy efficiency, mileage and reliability of new energy vehicles. At present, silicon-based IGBT (insulated gate bipolar transistor) and silicon carbide (SiC) power devices are two mainstream solutions, and they have their own unique application characteristics in new energy vehicles.

1. Application of silicon-based IGBT in new energy vehicles

IGBT is a composite fully controlled voltage-driven power semiconductor device composed of BJT (bipolar transistor) and MOS (insulated gate field effect transistor), which has the advantages of easy driving, simple control, high switching frequency, low on-voltage, large on-state current, and low loss. In new energy vehicles, IGBT is mainly used in motor controllers, on-board chargers (OBC), DC/DC converters and other components.

Motor controller: IGBT, as the core switching device of the motor controller, can achieve precise control of the motor. By adjusting the switching frequency and duty cycle of the IGBT, the motor speed, torque and running direction can be precisely controlled, thereby improving the driving performance and comfort of new energy vehicles.

On-board charger: In the on-board charger, IGBT, as a key component of the power factor correction (PFC) circuit and DC/DC conversion circuit, can achieve effective control of input current and stable regulation of output voltage, thereby improving charging efficiency and safety.

DC/DC converter: IGBT acts as the main switching device in the DC/DC converter, which can convert high voltage into low voltage or charge low-voltage batteries to meet the power requirements of different electrical equipment inside new energy vehicles.

However, silicon-based IGBTs also have some limitations, such as large on-resistance and high switching loss, which, to a certain extent, limit the performance improvement and energy efficiency improvement of new energy vehicles.

2. Application of Silicon Carbide (SiC) Power Devices in New Energy Vehicles

Silicon carbide (SiC) is a wide bandgap semiconductor material with advantages such as high breakdown electric field, high thermal conductivity, and high electron saturation mobility. Compared with silicon-based IGBTs, silicon carbide power devices have lower on-resistance and higher switching frequency, which can significantly improve the performance and energy efficiency of new energy vehicles.

Motor controller: Motor controllers using silicon carbide power devices can achieve higher switching frequencies and lower switching losses, thereby improving the control accuracy and response speed of the motor. In addition, the high thermal conductivity of silicon carbide power devices helps reduce the complexity and cost of the heat dissipation system.

On-board charger: The application of silicon carbide power devices in on-board chargers can significantly improve charging efficiency and power density. Due to their low on-resistance and high switching frequency, silicon carbide power devices can reduce the size and weight of the charger and improve charging convenience.

DC/DC converter: DC/DC converters using silicon carbide power devices can achieve higher conversion efficiency and smaller size, which helps improve the utilization of the internal space of new energy vehicles and the energy management efficiency of the entire vehicle.

In addition, silicon carbide power devices also have excellent properties such as high temperature resistance and radiation resistance, and can maintain stable performance in harsh working environments. These characteristics make silicon carbide power devices have broad application prospects in new energy vehicles.

3. Comparison between silicon-based IGBT and silicon carbide power devices

Performance: Silicon carbide power devices are superior to silicon-based IGBTs in terms of on-resistance, switching frequency, switching loss, etc. This enables silicon carbide power devices to achieve higher energy efficiency and better driving performance in new energy vehicles.

Cost: At present, the production process of silicon-based IGBT is quite mature and the cost is relatively low. However, the production process of silicon carbide power devices is still in the stage of continuous development and improvement, and the cost is relatively high. However, with the continuous advancement of silicon carbide technology and the realization of large-scale production, its cost is expected to gradually decrease.

Reliability: Due to the high temperature resistance and radiation resistance of silicon carbide materials, the reliability of silicon carbide power devices in harsh environments is better than that of silicon-based IGBTs. This makes silicon carbide power devices safer and more stable in new energy vehicles.

IV. Conclusion and Outlook

In summary, silicon-based IGBT and silicon carbide power devices have their own advantages and disadvantages in new energy vehicles. Silicon-based IGBT occupies a certain position in the new energy vehicle market with its mature production process and relatively low cost; while silicon carbide power devices have become an important direction for the technical upgrade of new energy vehicles with their excellent performance and reliability.

Looking ahead, with the continuous development and technological progress of the new energy vehicle industry, silicon carbide power devices are expected to occupy an increasingly important position in the new energy vehicle market. At the same time, silicon-based IGBTs will also meet the growing performance requirements of new energy vehicles through continuous technological innovation and optimization. The competition and cooperation between the two will jointly promote the prosperity and development of the new energy vehicle industry.