Detailed explanation of IGBT chip technology: why it is called the “core technology” in the field of electric vehicles
“There are many types of chips. Today, I will introduce a chip IGBT (Insulated-gate bipolar transistor) that is closely related to our lives. This chip is widely used in electric vehicles.
There are many types of chips. Today, I will introduce a chip IGBT (Insulated-gate bipolar transistor) that is closely related to our lives. This chip is widely used in electric vehicles.
IGBT is a chip used for output control of AC motors in electric vehicles, railway locomotives, and EMUs.
IGBT directly controls the conversion of direct and alternating current, which determines the torque of the drive system and the maximum output power. Therefore, it depends on your car’s acceleration ability, top speed, and energy efficiency.
IGBT accounts for about half of the cost of the motor drive system and 5% of the cost of the entire vehicle. It is the second most expensive component of the entire electric vehicle (the highest cost is the battery). It is no exaggeration to say that this is the “core technology” in the field of electric vehicles.
Structurally, IGBT mainly has three development directions:
1. IGBT longitudinal structure: non-transparent collector area NPT type, buffer layer PT type, transparent collector area NPT type and FS electric field cut-off type;
2. IGBT gate structure: planar gate structure, Trench trench structure;
3. Silicon wafer processing technology: epitaxial growth technology, zone melting silicon single crystal;
According to the packaging process, IGBT modules can be divided into welding type and crimping type. High-voltage IGBT modules are generally based on standard welding packaging, while many new technologies have emerged for medium and low-voltage IGBT modules, such as sintering instead of welding, and pressure contact instead of wire bonding.
With the continuous development of IGBT chip technology, the maximum operating junction temperature and power density of the chip continue to increase, and the IGBT module technology must also be adapted to it. In the future, the IGBT module technology will be improved in two aspects: “welding and fixing on the back of the chip” and “front electrode interconnection”.
Main application areas of IGBT
As the mainstream device of new power semiconductor devices, IGBT has been widely used in traditional industrial fields such as industry, 4C (communication, computer, consumer electronics, automotive electronics), aerospace, defense and military industry, as well as rail transit, new energy, smart grid, new Strategic emerging industries such as energy vehicles.
1. New energy vehicles
IGBT modules play a vital role in electric vehicles and are the core technical components of electric vehicles and charging piles. IGBT modules account for nearly 10% of the cost of electric vehicles and about 20% of the cost of charging piles. IGBTs are mainly used in the following aspects in the field of electric vehicles:
A) The electric control system drives the car motor after a high-power DC/AC (DC/AC) inverter;
B) Low-power DC/AC (DC/AC) inverter for vehicle air-conditioning control system, using IGBT and FRD with lower current;
C) The IGBT module in the charging pile smart charging pile is used as a switching element;
2. Smart grid
IGBTs are widely used in power generation, transmission, substation and power consumption of smart grids:
From the perspective of power generation, rectifiers and inverters in wind power generation and photovoltaic power generation all require the use of IGBT modules.
From the perspective of the transmission end, the FACTS flexible transmission technology in UHV DC transmission requires a large number of power devices such as IGBTs.
From the point of view of the substation, IGBT is the key component of the power Electronic transformer (PET).
From the perspective of power consumption, household white electricity, microwave ovens, LED lighting drivers, etc. all have a large demand for IGBTs.
3. Rail transit
IGBT devices have become mainstream power electronic devices for traction converters and various auxiliary converters of rail transit vehicles. AC drive technology is one of the core technologies of modern rail transit. In the AC drive system, the traction converter is a key component, and the IGBT is one of the core components of the traction converter.