QPT patents technologies to enable GaN up to 20MHz
QPT claimed to be the first company to create the technologies needed to enable GaN to operate at well over the current limitations of 100kHz and up to 20MHz. Target applications are high power, high voltage applications that use hard switching such as motor drive systems for HVAC or robotics.
GaN transistors are significant for next-generation power electronics because they have the ability to operate at high frequencies for switching on and off which results in a faster transition with less energy loss, explained QPT. GaN can transition from on to off very quickly at one to two nanoseconds as opposed to 20 to 50ns for Si (silicon) and SiC (silicon carbide) transistors, the company explained.
In high voltage, high power applications, however, there is a practical limit of 100kHz for GaN beyond which the issues of overheating and RF interference become too great, continued QPT.
The company has integrated its GaN technology into two modules that it can be easily implemented by customers with minimal effort and changes to existing designs. The qGaN module contains a 650V GaN transistor with the company’s qDrive, which is claimed to be the world’s fastest, most accurate, highest resolution, low jitter isolated GaN transistor gate drive. The second module is qSensor that combines the company’s ZEST and qSense technologies. It provides the sensing and control that enables the GaN to be driven at ‘super high’ frequencies for the first time.
QPT has also developed its WisperGaN construction system that includes a reference design for how the modules and the ancillary electronics can be assembled together in a Faraday cage so that there are no heating or RF issues. This unlocks the ability of GaN to operate at high frequencies and provides up 80 per cent reduction in power usage compared to existing solutions that have to operate at much lower frequencies, said the company.
The first qGaN module (Q650V15A-M01) will handle 15A RMS current driving 380V three-phase motors. The reference design is drop-in replacement for the power stage of existing VFDs (variable frequency drives) without the need for any specialist expertise in EMC or thermal cooling.
The company also introduced a roadmap of qGaN modules to handle different power loads to suit different application area requirements. Together with the other QPT technology modules, turnkey solutions can be easily assembled according to the reference design, the company said. The rest of the existing system such as the microprocessor and software stack stay the same, confirmed QPT, resulting in a lower power budget and savings in bill of materials as no external filters are required.
Companies who want to upgrade from silicon solutions can leapfrog to GaN without having to develop an SiC design in-house, said the company. Combining the VFD power saving of around 80 per cent with the motor usage gives around 10 per cent reduction in overall power usage, which increases in applications where the motor is frequently at low speeds where the current solutions are inefficient, it continued.
