| 摘要 |
In an inverter, in order to reduce the effect of the distributed inductance contributed by conductors 7a, 8a used to connect DC smoothing capacitances 2 and switching elements 1, and thus the need for large snubber capacitances 9 to compensate for the distributed inductances. the conductors 7a, 8a are given a geometry and an orientation that causes the inductances to be minimized. The conductors 7a, 8a are of a bus-plate form, having a large area for improving heat dissipation, and an orientation so that the magnitude and direction of currents flowing through the bus-plates tend to minimize the effect of the distributed inductances. The bus-plates may comprise one or more separate conductive plates and may be shaped to provide slots (30, Fig 4) for viewing explosion proof valves (29) on the capacitors. The switching elements 1 may be IGBT, MOST or bipolar transistors. The inverter unit can be used for driving a motor with multi-phased currents, each of the phases being derived from a.c. input voltages that are applied to respective input terminals, rectified and smoothed by the capacitors 2 before being applied to parallel-connected switching elements 1 to develop each of the phased a.c. outputs. <IMAGE> |
