Low impedance bus for power electronics

Abstract

A low impedance, high power bus for conduction of electrical power with reduced transient signal effects is described herein. The high power bus can be applied as a high power supply bus between a constant voltage source and a plurality of switching cells positioning at varying locations along the bus, and as branch bus for the switching cells. The power bus can transmit high power: large currents in the hundreds or thousands of amperes, and large voltage potentials in the hundreds or thousands of volts. Particularly, the power bus has use in a DC-to-AC inverter that converts DC from a constant voltage source into three-phase AC for delivery to an electrical power grid. The high power bus includes two conductive bars positioned so that the current flow therethrough is balanced (equal and opposing), and the magnetic field is substantially confined between the bars. The bus includes a dielectric positioned between the conductive bars. In a preferred embodiment, the AC is conducted on extension bars that extend along the power supply bus, so that a main bus is created by the combination of the AC extension bars and the DC power supply bus, and the sum of the currents in the bars is approximately zero at all locations in the bus. The power bus lessens or even obviates the need for the snubber networks commonly used to reduce transients, and reduces the strength of magnetic fields and electric fields that could otherwise interfere with neighboring electrical components.