Quicker and more efficient charging thanks to SiC FET technology
With the UF3SC series from UnitedSiC, Angst+Pfister Sensors and Power (formerly Pewatron) presents a new generation of SiC FET circuit breakers with outstanding properties. The RDSon on-state resistance plays an essential role here. The lower the resistance of the switch, the lower the heat losses. With an RDSon of less than 9 mOhm at 1,200 volts, the UF3SC series offers the lowest value currently available. SiC technology also enables higher switching frequencies than are possible with IGBT, and thus smaller designs. This allows for a significant increase in efficiency – a key aspect for outputs in the kW range. Another benefit: the reverse recovery charge Qrr of the body diode is virtually temperature independent. In connection with a positive temperature coefficient for RDSon, this is advantageous for parallel connections as the asynchronous load on the switches is minimised. Due to the low leakage and a threshold voltage Vth > 3 V, operation up to a temperature Tj > 200°C (SiC TJMax = 175°C) is possible without the risk of thermal runaway. For inverters in the field of e-mobility, the very low and virtually temperature-independent switching energies Eon and Eoff of the UF3SC series are ideal, and this is further supported by the excellent recovery characteristics of the body diode. The SiC FET circuit breakers are based on a cascode circuit consisting of a SiC JFET and a Si MOSFET. They can be used in connection with standard gate drivers, making them suitable as a real drop-in replacement for Si IGBTs, Si FETs or SiC MOSFETs. Due to the new international standard ISO 15118-20 for charging infrastructure, 1,200V SiC FETs are also becoming more important for the control of the bidirectional function of charging units, i.e. the control of active power P and reactive power Q. In addition to the SiC FET circuit breakers, Angst+Pfister Sensors and Power offers a comprehensive range of other state-of-the-art components for power electronics. The new BeFAST evaluation board also provides a ready-to-use development tool for determining all relevant circuit properties in interaction with other essential components such as DC-DC converters, insulators, thermistors, etc.
