US 5,963,441 A · Alternating current rectifier bridge and system for measuring average current per bridge segment

Abstract

A three-phase controlled rectifier bridge for converting alternating current to direct current includes six segments for each of the positive and negative polarities of each of three AC phases. Each of the segments has a semiconductor controlled rectifier element responsive to a control signal to control current conduction within the segment. A conduction monitor, which is provided for each of the AC phases, monitors a corresponding one of the AC phases to provide a conduction monitor signal. A first shunt current sensor senses current of the segments for the positive polarity of the AC phases and provides a first current signal. A second shunt current sensor senses current of the segments for the negative polarity of the AC phases and provides a second current signal. A control and monitoring circuit has outputs which output the control signals to the segments to control current conduction within the segments, and a microprocessor-based firmware routine which employs the conduction monitor signals and the first and second current signals to determine an average current for each of the segments.

Claims19

Dependent claims

A controlled rectifier bridge for converting alternating current to direct current, said alternating current having a plurality of phases each of which has a positive polarity and a negative polarity, said bridge comprising:

a segment for each of said positive and negative polarities of each of said phases of said alternating current, each of said segments having an element responsive to a control signal to control current conduction within said segment;
a monitor for each of said phases of said alternating current, each of said monitors monitoring a corresponding one of said phases to provide a conduction signal;
a first current sensor sensing current of said segments for said positive polarity of said phases of said alternating current, said first current sensor providing a first current signal;
a second current sensor sensing current of said segments for said negative polarity of said phases of said alternating current, said second current sensor providing a second current signal;
means for outputting the control signals to said segments to control current conduction within said segments;
and
means employing said conduction signals and said first and second current signals for determining an average current for each of said segments.

4 more elements

A system for converting alternating current to direct current, said alternating current having a plurality of phases each of which has a positive polarity and a negative polarity, said system comprising:

a plurality of controlled rectifier bridges each of which comprises:
a segment for each of said positive and negative polarities of each of said phases of said alternating current, each of said segments having an element responsive to a control signal to control current conduction within said segment,
a monitor for each of said phases of said alternating current, each of said monitors monitoring a corresponding one of said phases to provide a conduction signal,
a first current sensor sensing current of said segments for said positive polarity of said phases of said alternating current, said first current sensor providing a first current signal,
a second current sensor sensing current of said segments for said negative polarity of said phases of said alternating current, said second current sensor providing a second current signal,
means for outputting the control signals to said segments to control current conduction within said segments, and
means employing said conduction signals and said first and second current signals for determining an average current for each of said segments;
and
a central control circuit to control said rectifier bridges.

6 more elements

Dependencies are inferred from the claim text.

Alternating current rectifier bridge and system for measuring average current per bridge segment

Life of this patent

Alternating current rectifier bridge and system for measuring average current per bridge segment

Life of this patent

Abstract

Claims19