Optimising the resonant link in resonant link converters

In resonant link converters a new approach to the problem of low loss switching in voltage fed converters has been taken. Several considerations require that-in order to derive maximum benefit from this technology-the resonant frequency be in the ultrasonic range (20 kHz to 100 kHz), whether bipolar transistors or GTOs are used as switching elements. The losses in the input resonant link has therefore to be kept as low as possible at these frequencies. Furthermore, the larger part of the losses is due to the inductor in the link. Although this resonant inductor need only be some microhenries, it should also be kept in mind that it carries the sum of the full inverter input current and the resonant current. The authors investigate the minimization of the losses in this inductor by appropriate high frequency design as well as how changes in the link components influences peak voltage stresses and increased turn-off losses in the inverter switching components