GaN can now function at up to 20 MHz without overheating or RF problems thanks to a patented set of technologies, opening up a broad new field of application. GaN can now operate at frequencies considerably above the present cap of 100 kHz up to 20 MHz in high power, high voltage applications utilizing hard switching, such as motor drive systems for HVAC, robotics, and other devices. This ground-breaking method closes a significant hole in the GaN market for which no other workable solution has been discovered. GaN transistors’ ability to turn on and off at extremely high frequencies makes them essential for the upcoming generation of power electronics. Slow transitions waste energy because the transistor loses a lot of power while switching, leading to energy waste and overheating issues. The faster the switching speed, the less time is lost in transition and energy is wasted. GaN transistors can switch from being on to being off much faster than Si and SiC transistors, which need 20 to 50 ns to do so.
In high voltage, high power applications, however, there is a realistic limit of 100 kHz, above which the issues of overheating and RF interference become too severe. The current strategy is to throttle back GaN to sub-100 kHz, which produces in performance that is comparable to Silicon Carbide and negates any advantages of utilizing GaN because GaN is not functioning at high switching speeds or frequencies, where it genuinely delivers power savings. QPT has combined its technology achievements into two modules to make it easy for clients to use and adapt current designs. The qGaNTM module drives a 650V GaN transistor using the company’s qDriveTM, the fastest, most accurate, highest resolution, minimum jitter isolated GaN Transistor Gate Drive in the world. The second module, qSensorTM, combines the company’s ZESTTM and qSenseTM technologies. It provides the sensing and control required to drive the GaN at very high frequencies for the first time. For their WisperGaNTM assembly system, QPT has also produced a reference design for how the modules and the auxiliary electronics can be arranged in a Faraday cage so that there are no heating or RF issues. The resulting technique enables GaN to operate at ultrahigh frequencies and provides up to 80% power savings compared to conventional systems, which must operate at much lower frequencies. The first qGaN module (Q650V15A-M01) will be able to supply 15A RMS current to drive 380V three-phase motors. In order to address the demands of many application areas, the roadmap will incorporate qGaN modules to manage a variety of different power loads. Using the additional QPT technology components in accordance with the reference design, turnkey systems can be assembled fast. The reference design can be used to swap out the power stage of current VFDs without the need for specific understanding in EMC or thermal cooling.
