US 5,172,310 A · 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.

Claims26

Dependent claims

A low-noise power bus assembly with balanced current flow and reduced transient signal effects, for conducting DC current for high speed switching by high speed transistors, and for conducting an AC waveform defined by switching said high speed transistors, said power bus assembly comprising:

an assembly having a first plurality of conductors coupled to said high speed transistors to receive and conduct DC current, and further having a second plurality of conductors coupled to said high speed transistors to receive and conduct AC current, said first conductors and said second conductors positioned in groups, each group including at least two of said conductors, and within each of said groups, the conductors having a shape and relative position so that each conductor is positioned with respect to at least one adjacent conductor and the currents flowing through each of said adjacent conductors are substantially balanced (equal in amount and opposite in direction);
and,
a plurality of dielectric layers disposed within said assembly, wherein said dielectric layers are interposed between said adjacent conductors.

A low-noise power bus assembly with balanced current flow and reduced transient signal effects, for conducting DC current for high speed switching, and for conducting an AC waveform, said power bus assembly comprising:

a plurality of switching cells, each of which includes at least one high power transistor;
an assembly having a first plurality of conductors coupled to receive and conduct DC current to said plurality of switching cells, and further having a second plurality of conductors coupled to receive and conduct AC current from said plurality of switching cells, said first conductors and said second conductors having a shape and relative position so that a magnetic field created by the currents flowing therein are substantially contained between said first and second conductors, and wherein two or more of said first and second conductors are configured so that the currents flowing therein are substantially balanced (equal in amount and opposite in direction);
a plurality of dielectric layers disposed within said assembly, wherein said dielectric layers are interposed between said conductors;
and
wherein the assembly has a configuration for a DC-to-AC three phase inverter so that
said first conductors include a DC power supply bus;
said second conductors include a phase A extension bar, a phase B extension bar, and a phase C extension bar;
and,
said extension bars and said power supply bus are positioned in a parallel configuration so that the flows of current within said extension bars and said DC power supply bus are substantially balanced.

6 more elements

A low-noise, low impedance power bus assembly for conducting electrical power between a constant DC voltage supply and an AC waveform, using a plurality of switching cells for switching between AC and DC electrical power, said power bus assembly comprising:

a power supply bus for conducting DC current to the switching cells, said power supply bus including a pair of parallel bus bars, a +DC bus bar and a -DC bus bar, positioned in an adjacent relationship so that the flows of current in said bus bars are in respectively opposing directions, and further including a dielectric positioned between said adjacent bus bars;
a first +DC bus connector bar for connecting the +DC bus bar to a first +DC electrical switching cell;
a first -DC bus connector bar for connecting the -DC bus bar to a first -DC electrical switching cell, said first bus connector bars being positioned on opposite sides of the power supply bus;
a first AC bar having a first end coupled to the first +DC electrical switch, and a second end coupled to the first -DC electrical switch, said first AC bar having a +DC section situated in an opposing, parallel, adjacent relationship with the first +DC bus connector bar, and a -DC section situated in an opposing, parallel, adjacent relationship with the first -DC bus connector bar so that the current flow through each section of the first AC bar opposes the current flow through the adjacent DC bus connector bar;
and,
a dielectric layer positioned between the adjacent sections of the first AC bar and the first DC bus connector bars.

3 more elements

A low-noise power inverter for converting electrical energy between electrical energy at a substantially constant voltage and three phase AC electrical energy by high speed switching, said low-noise power inverter comprising:

a power supply bus for conducting current from the voltage source, said power supply bus including a pair of parallel bus bars including a +DC bus bar and a -DC bus bar, positioned in an adjacent relationship so that their flows of current are in respectively opposing directions, and further including a dielectric positioned between the bus bars of the power supply bus;
a plurality of pairs of switching cells, each cell including a first switching cell and a second switching cell;
and,
a plurality of branch buses for connecting the power supply bus with the plurality of switching cells and providing an output therefrom, said branch buses positioned along the length of the power supply bus, each branch bus including
a first bus connector bar connecting the power supply bus with a first switching cell of a selected pair of switching cells,
a second bus connector bar connecting the power supply bus with a second switching cell of said selected pair of switching cells,
an AC bar for supplying an output from the first and second switching cells, said AC bar coupled to the first and second switching cells, said AC bar being situated in an opposing, parallel, adjacent relationship with the first and second DC bus connector bars so that the current flow through the first DC bus connector bar and a section of the AC bar adjacent thereto is substantially balanced, and the current flow through the second DC bus connector bar and a section of the AC bar adjacent thereto is substantially balanced, and,
a dielectric positioned between each AC bar and the DC bus connector bar adjacent thereto.

5 more elements

Dependencies are inferred from the claim text.

Low impedance bus for power electronics

Life of this patent

Low impedance bus for power electronics

Life of this patent

Abstract

Claims26