US 5,798,916 A · High power inverter pole employing series connected devices configured for reduced stray loop inductance

Abstract

A high power inverter pole for a voltage sourced inverter suitable for providing compensation in electric power transmission and distribution systems, has a positive switching valve and a negative switching valve connected between closely spaced dc-source terminal, respectively, and a common ac terminal to form a current loop with minimum loop area thereby reducing stray loop inductance and limiting the overshoot voltage on serially connected electronic switches which make up the valves. In a preferred embodiment, the valves are mounted on opposite sides of the web of an insulative I-beam. The electronic switches are incorporated in modular switching units connected in series by C-channel connecting conductors having flanges bolted to the I-beam flanges. The modular units include broad, flat conductors bolted through end flanges to the C-channel connecting conductors. The electronic switches and anti-parallel diodes of the modular units are clamped between these broad, flat conductors. Cooling water is circulated through the broad, flat conductors which serve as heat sinks as well as providing low inductance electrical connections. In another embodiment of the invention, sections of the positive and negative switching valves are folded back on themselves to minimize loop area and hence again, reduce stray loop inductance.

Claims28

Dependent claims

Switching pole for a high power electronic voltage sourced inverter connected between an ac bus forming an ac terminal and a dc-source having a positive dc bus and a negative dc bus positioned to form closely spaced positive and negative dc terminals, said switching pole comprising:

a positive switching valve comprising a first set of switching units and a first set of connecting conductors connecting said first set of switching units in series to form a positive electrical path between said positive dc terminal and said ac terminal;
a negative switching valve comprising a second set of switching units and a second set of connecting conductors connecting said second set of switching units in series to form a negative electrical path between said negative dc terminal and said ac terminal;
mounting means mounting said positive switching valve and said negative switching valve so that said positive electrical path and said negative electrical path form a loop having a minimum loop area, wherein said first and second set of connecting conductors in said positive switching valve and said negative switching valve each comprise broad, flat conductors having an aspect ratio of width to spacing between facing connecting conductors in said loop of at least about 1:1;
and
limiter means limiting electrical parameters of said positive and negative electrical paths connected to said positive and negative switching valves.

2 more elements

A multi-pole, high voltage, electronic, voltage sourced inverter bridge connected between a multi-phase ac bus forming ac terminals and a dc-source having a positive dc bus and a negative dc bus positioned to form closely spaced positive and negative dc terminals, said inverter comprising:

a plurality of switching poles, each comprising:
a positive switching valve comprising a first set of switching units and a first set of connecting conductors connecting said first set of switching units in series to form a positive electrical path between said positive dc terminal and a selected one of said ac terminals;
a negative switching valve comprising a second set of switching unit and a second set of connecting conductors connecting said second set of switching units in series to form a negative electrical path between said negative dc terminal and said selected ac terminal;
limiter means limiting electrical parameters of said positive and negative electrical paths connected to said positive and negative switching valves;
and
mounting means mounting said positive switching valve and said negative switching valve of each of said switching poles so that the positive electrical path and the negative electrical path form a minimal loop area, and with said switching poles stacked one on top of another, wherein said first and second set of connecting conductors in said positive switching valve and said negative switching valve each comprise broad, flat conductors having an aspect ratio of width to spacing between facing connecting conductors in said loop of at least about 1:1.

3 more elements

Dependencies are inferred from the claim text.

High power inverter pole employing series connected devices configured for reduced stray loop inductance

Life of this patent

High power inverter pole employing series connected devices configured for reduced stray loop inductance

Life of this patent

Abstract

Claims28