Current situation and trend Analysis of Electric Drive system [Electric opportunity]

At the 2021 annual meeting of China International Motor Industry chain hosted by Shanghai Nonferrous Network (SMM), Wang Jian, an industry analyst at Gaishi Automotive Research Institute, analyzed the current situation and trend of electric drive systems. He pointed out that China's new energy vehicle market has entered a market-driven development period. In recent years, China's new energy vehicle market has developed rapidly under the continuous drive of policies, the industrial foundation has been continuously improved, technology and products have been continuously improved, market sales have continued to rise, and consumers have also moved and upgraded from the B end to the C end, entering a new stage of market-driven development.

Background of industry development

China's new energy vehicle market has entered a market-driven development period. in recent years, China's new energy vehicle market has developed rapidly under the continuous drive of policies, the industrial foundation has been continuously improved, technology and products have been continuously improved, market sales have continued to rise, and consumers have also moved and upgraded from the B end to the C end, entering a new stage of market-driven development.

In China's "Energy Saving and non-New Energy vehicle Technology Roadmap 2.0", it has made clear the future development goals of China's new energy passenger vehicles and the detailed technology development goals of the electric drive system in the future, leading and standardizing the healthy development of the industry from the top-level architecture.

Current situation of electric drive market

The installed capacity of electric control of motors is rising rapidly: in the first three quarters of 2021, the total installed capacity of electric drive systems of new energy passenger vehicles is 2.198 million, which is 176.8% of the total installed capacity of 2020. In the first three quarters of 2021, motor electric control cumulative supporting TOP10 enterprises, including Tesla, Fudi Power, Weiran Power, Shanghai Electric Drive, Nippon Electric, United Electronics, Huichuan and other seven enterprises.

The three-in-one electric drive system has become the mainstream product: the three-in-one electric drive system with compact structure and more convenient for vehicle layout has become the mainstream product. The share of three-in-one electric drive systems in the domestic passenger car market has reached nearly 75% in the first three quarters of 2021, nearly three times higher than the 26% in 2019.

Many forces are laying out the electric drive system industry: at this stage, there are mainly multiple camps in the electric drive market, such as OEM independent supporting, third-party enterprise supporting and so on. The vertically integrated OEM is more dominant, but the industrial final result has not been formed. In the next stage, it is easier for OEM to cut into the field of motor control, and third-party enterprises should join forces to form technical barriers to seek the future.

Development trend of Electric Drive Technology

The overall development is in the direction of integration, high efficiency, high power density and high voltage: starting from the pain points of consumers' purchase of electric vehicles and the development needs of the whole vehicle, combined with the key attributes of the electric drive system, the electric drive system will develop in the direction of integration, platform, high efficiency, high power density, high voltage and so on.

Multi-in-one system and power domain controller is the next step of integration direction: in the future, with the development of electronic and electrical architecture towards domain control, domain fusion and even central controller, the next step of electric drive assembly integration direction will be multi-in-one and domain controller. However, the higher the degree of integration, the challenges of EMC, thermal management and failure will also increase on Synchronize.

Hub motor is difficult to mass produce in passenger cars in a short time: as the main scheme of distributed drive technology, hub motor has the characteristics of few system components, simple structure, high degree of integration and so on. Compared with other driving technical schemes, hub motor drive can effectively improve the driving efficiency and improve the ride space in the car. However, technical problems such as high cost, high spring quality, protection, vibration and reliability limit it is difficult to carry passenger vehicles for mass production in a short period of time.

The innovation of structure, process and material has become the focus of improving motor efficiency: in the electric drive system, the power loss mainly comes from the motor and reducer, and the performance of motor power and speed can be improved through the innovation of structure, process and material. The main technical trends are flat wire winding electronics, oil cooling technology, high performance magnetic steel and so on.

The third generation power semiconductor silicon carbide is the key to realize the high voltage of the electric drive system: when the whole vehicle voltage platform develops to a higher voltage, the voltage of the voltage withstand device of the electric drive system will also increase, in addition, with the high speed of the motor, the switching frequency of electric control also needs to be increased. Under the common requirements of both, the application of the third generation power semiconductor silicon carbide with high voltage withstand grade and wide switching frequency range will become the key. In the future, with the gradual increase of the third generation power semiconductors of SiC, IGBT will not form a complementary situation.

The advantage of using silicon carbide after electric drive will be more obvious: with the use of the third generation silicon carbide power semiconductors on the high voltage platform, the efficiency of the whole electronic control system will be greatly improved due to the substantial reduction of SiC switching loss and its own power consumption, and the mileage can be extended or the battery consumption can be reduced with the same mileage to reduce the cost.

There are still many challenges in the application of silicon carbide power semiconductors: the biggest factor restricting the development of SiC devices comes from cost and manufacturing process, but with the improvement of production process and saving of parts and components, the cost will be reduced to a certain extent, which will promote the commercialization of SiC.