Experimental Investigation of Prototype All-SiC Converter for Ultra-High-Speed Elevator

As the population concentration in large cities steadily increases, buildings will require even more energy savings. Articles about the effect of converters using SiC, which is a low-loss power device, have been reported in various applications. We developed a prototype of a compact converter using SiC-MOSFETs for elevators and evaluated the energy savings in actual elevator operation. In a former paper, we reported the following two results. The first was the prototype control panel in the all-SiC converter had a 57% smaller setting area than that of the conventional one using Si-IGBT. The other was an energy savings of approximately 17% was achieved in the total elevator system under a high temperature condition. In this paper, we present our analysis of the power loss of the converter for the possibility of further energy savings. Approximately 70% of the total energy loss of the all-SiC module was found to be switching loss, that is, turn-on loss and turn-off loss. This result suggests that we can expect further energy savings using faster switching with a higher dv/dt to reduce switching loss. Overall, we estimated energy savings of about 20% in an elevator system under higher dv/dt switching.