Driving methods of the High Voltage GaN transistor module

Abstract

With the development of new WBG semiconductor structures, new challenges are emerging for their use in various applications. The challenge for GaN transistors is to achieve a blocking voltage higher than 650V. There are relatively few manufacturers of GaN transistors on the market that offer higher blocking voltages than 650V. For example, if we were to use these transistors in an 800V DC converter system, we would need a transistor with a minimum blocking capacity of 1000V, including a margin of 20%. For the electric vehicle power conditioning system, a gallium nitride (GaN) power switching module with an enhanced rated voltage is proposed. GaN high-electron-mobility transistors (HEMTs) have a low breakdown voltage, which makes them unsuitable for high-voltage applications. GaN transistors may be coupled in a stacked manner, thereby doubling their blocking capabilities. If 650V transistors are employed, the blocking capacity in stacked form is 1300V. This design has various advantages but also disadvantages, which are mentioned in. One of the main disadvantages of this connection is the complex driving of the transistors so that the deviation of the redistributed voltage between the transistors is not high and thus the device is not damaged. So this article discusses gate driving solutions, which contain design and experimental results.