Development Status and Trend Analysis of IGBTs for Key Parts of Electric Vehicles

1. Introduction to IGBTs (1) IGBT (Insulated Gate Bipolar Transistor) is a fully-controlled voltage-driven power electronic device consisting of a BJT (bipolar transistor) and an MOS (insulated gate field effect transistor). It has both MOSFET inputs. The advantages of high impedance, low control power, simple drive circuit, high switching speed, and bipolar power transistor have the advantages of high current density, reduced saturation voltage, and strong current handling capability.

(2) The IGBT module is one or more IGBT chips mounted on an insulating substrate, and the substrate is fixed on a heat-dissipating copper substrate. In order to facilitate system assembly and keep the lead inductance inside and outside the module to a minimum, freewheeling diodes are also installed in the module.

(3) The main application areas of IGBTs include industrial control, consumer electronics, computers, and network communications. Electric vehicles are emerging applications for IGBTs and have new requirements for IGBTs.

Vehicle IGBT environmental conditions and reliability requirements are shown in Tables 4-5. The industrial-grade and automotive-grade IGBT reliability requirements are shown in Tables 5-5.

2. Foreign Development Situation Traditional IGBT manufacturers are mainly concentrated in Europe, the United States and Japan.

Among them, companies such as Infineon, Fuji Electric, Mitsubishi Electric and Ximenkang have conducted research on IGBTs for vehicles and successfully launched products to meet the demand for electric vehicles and have been widely applied in electric vehicles.

(1) Infineon introduced HybridPACK series IGBT modules for electric vehicles. Currently, there are HybridPACK1 and HybridPACK2 products. The maximum power is 20kW and 80kW, which are applicable to light-mixed and fully-mixed automobiles. In addition, PrimePACK series IGBT modules can meet higher power requirements and can be used in trucks and buses.

(2) Fuji Electric's products are used on Toyota Hybrid Camry, and its products are suitable for 10kW to 120kW drive motor systems.

(3) Mitsubishi Electric mainly manufactures IGBT modules. The discrete devices are manufactured by Renesas Semiconductor (a joint venture between Mitsubishi Electric and Hitachi). Its automotive IGBT products have been applied to hybrid vehicles such as Honda and Toyota.

(4) The solderless IGBT module introduced by Semikron, using Infineon's chips, is suitable for 22-150kW motor controller for electric vehicles.

3. China's IGBT development status (1) China's IGBT has just started, mainly through the outsourcing of IGBT chips, the traditional industrial-grade standard module package, the main enterprises are Jiangsu Hongwei, Nanjing Yinmao, Jiaxing Star, Weihai Xingjia, Xiamen Hongfa, etc. the company. In addition, some downstream companies in the industrial chain acquired power semiconductor devices through acquisitions, such as BYD and CSR. Some companies have begun to study high-power automotive IGBT modules.

(2) R&D Capabilities The core technologies of IGBTs include chips and module packages. The company basically has IGBT chip design capabilities, but lacks manufacturing capabilities and industrialization is still a long time away. The company has now basically had module design, packaging, detection and analysis capabilities by introducing foreign equipment and returning talents, and can realize IGé„„BT modules. Independent production.

(3) Product Status At this stage, China's IGBT modules are generally concentrated in 600V and 1200V, and products with higher voltage levels are under research and development. The main application areas are industrial inverters, welding machines, and induction heating.

At present, the product has not yet been fully accepted by domestic customers and is currently in the certification period of the market customers. Companies also pay more attention to the field of electric vehicles. The research and development of IGBT modules for vehicles has only a few prototype applications. The industrialization of these products has yet to be improved with product technology and market cultivation.
4. Main problems of IGBTs in China (1) The IGBT chips are completely dependent on imports. The key technologies are monopolized by foreign companies, making it difficult to achieve breakthroughs at home and it is difficult to reduce costs.

(2) The reliability and stability of industrial-grade products still have a certain gap with foreign countries; IGBTs for vehicles are basically in the research and development stage, and there are major problems in reliability and electromagnetic compatibility.

(3) The level of R&D of high-power devices in China is far from that of foreign countries. Recently, the R&D strength of various companies is weak. The development talents are mainly based on “sea returnees”.

(4) The existing standards are for specific uses only and lack the automotive-grade IGBT standard, which is not suitable for industrialization.

China Electric Vehicle Key Parts Development Suggestions 1 . The main problems existing through comprehensive analysis, the main problems of key components of electric vehicles in China are summarized as follows:

(1) The manufacturers of electric vehicle parts and components are more cautious about entering the electric vehicle industry. They mainly rely on the profits of traditional products and national research funds for key parts of electric vehicles. The lack of investment in follow-up research and development of R&D will directly affect the industrialization of parts and components. development of.

(2) At present, in the domestic industrial alliances, the technical cooperation between the automaker and the parts factory is not close, and cross-industry collaboration and development are difficult. The actual cooperation of most industrial alliances has not been carried out.

(3) The spare parts company lacks R&D capability and lacks core R&D talents, especially those specialized in diaphragm materials, battery system integration, power electronics and motor control systems.

(4) The domestic manufacturers of parts and components manufacturing equipment are weak in technology, and some of the key production equipments rely on imports, resulting in increased investment costs and affecting the industrialization process.

(5) The former parts and components standard system is still not perfect, especially the key battery materials, batteries, motors, IGBTs, etc., affecting the healthy development of the industry.

(6) Electric auxiliary systems such as electric steering, electric air conditioning, electric vacuum assisted braking, etc. have not been industrialized yet, and industrialization is still needed.