Onsemi, a prominent player in intelligent power and sensing technologies, has recently announced its latest range of ultra-efficient 1200 V insulated-gate bipolar transistors (IGBTs). These new IGBTs are designed to minimize conduction and switching losses at an industry-leading performance level. The primary goal of these IGBTs is to improve the efficiency of fast-switching applications in energy infrastructure, such as solar inverters, uninterruptible power supplies (UPS), energy storage, and EV charging power conversion.
In the context of power electronics, switching losses refer to the energy dissipated as heat during the switching of a semiconductor device (such as a transistor) between its on and off states. When a transistor switches on, it must charge its capacitance and reduce its internal resistance, which requires a certain amount of energy. When it switches off, it must discharge its capacitance and dissipate stored energy, which again requires energy. The energy lost during these processes is dissipated as heat, which can reduce the efficiency of the circuit and potentially cause overheating of the device. Minimizing switching losses is important for improving the efficiency of power electronics systems, especially in high-frequency applications.
The new 1200 V Trench Field Stop VII (FS7) IGBTs are used to boost input to high voltage (Boost stage) as well as the inverter to provide an AC output in high switching frequency energy infrastructure applications. The low switching losses of FS7 devices enable higher switching frequencies that reduce the size of magnetic components, increasing power density and reducing system cost. For high-power energy infrastructure applications, the positive temperature coefficient of FS7 devices enables easy parallel operation.
Boost stage is a circuit that increases the voltage of a DC power source to a higher level, typically for use in energy infrastructure applications such as inverters, UPS, energy storage, and EV charging power conversion. The boost stage typically consists of a switching device (such as a transistor), an inductor, and a diode, and works by periodically storing energy in the inductor when the switching device is on and releasing it when the switching device is off, effectively boosting the voltage. Boost converters are commonly used in applications where the input voltage is lower than the desired output voltage, and are often used in conjunction with other power electronics circuits to convert, store, and distribute electrical energy efficiently.
According to Asif Jakwani, senior vice president and general manager of the Advanced Power Division, which is part of the Power Solutions Group at Onsemi, “As efficiency is extremely critical in all high switching frequency energy infrastructure applications, we focused on reducing turn-off switching losses and providing the best switching performance in this new range of IGBTs. This industry-leading performance allows designers to meet their most challenging efficiency requirements in very demanding high power energy infrastructure applications.”
The FS7 devices come in high-speed (S-series) and medium-speed (R-series) options. All devices include an optimized diode for low VF, tuned switching softness, and can operate with junction temperatures (TJ) up to 175°C. The S-Series devices, such as FGY75T120SWD, offer the best switching performance among currently available 1200 V IGBTs in the market. Tested with currents up to 7 times the rated value, this highly rugged IGBT platform also offers best-in-class latch-up immunity. The R-Series is optimized for medium-speed switching applications, such as motor control and solid-state relay, where conduction losses occur. FGY100T120RWD shows a VCESAT as low as 1.45 V at 100A, an improvement of 0.4 V over previous generation devices.
Overall, these ultra-efficient 1200 V IGBTs represent a significant step forward in energy infrastructure technology. With their improved efficiency, high switching frequencies, and easy parallel operation, these IGBTs have the potential to revolutionize the way we think about energy infrastructure. Their ability to reduce system cost and increase power density also makes them an attractive option for energy companies looking to reduce their environmental impact and increase their profitability.