Technology Trends in Power Devices

At switching powers below 10 kVA the classical bipolar devices are attacked by MOSFETs. Their main advantages are higher switching speed and less expensive drive circuits. In the power range up to 100 kVA large bipolar transistors with votlages of 400 - 1000 V are of growing interest. On the other hand, asymmetric thyristors (ASCR) and gate turn-off thyristors (GTO) can also reduce weight and volume of the equipment. Above 100 kVA thyristors still dominate due to their unsurpassed current and voltage capability.