Switch current sensors

Patent metadata

Field	Value
Publication number	US-12573550-B2
Application number	US-202318839405-A
Country	US
Kind code	B2
Filing date	Feb 16, 2023
Priority date	Feb 16, 2022
Publication date	Mar 10, 2026
Grant date	Mar 10, 2026

Abstract

A switch current sensor includes a summing circuit, at least one first-type switch current sensor subcircuit and configured to be coupled at a first input to a conductor, and coupled at a first output to the summing circuit, and at least one second-type switch current sensor subcircuit configured to be coupled at a second input to the conductor and coupled at a second output to the summing circuit. The summing circuit is configured to aggregate the first output of the at least one first-type switch current sensor subcircuit and the second output of the at least one second-type switch current sensor subcircuit to obtain a voltage waveform that is proportional to a switch current configured to flow in the conductor, the voltage waveform including a DC component and steady-state AC components of the switch current.

First claim

What is claimed is:

1 . A switch current sensor, comprising:
a summing circuit; at least one first-type switch current sensor subcircuit having a first input and a first output and configured to be coupled at the first input to a conductor, and coupled at the first output to the summing circuit; and at least one second-type switch current sensor subcircuit having a second input and a second output and configured to be coupled at the second input to the conductor and coupled at the second output to the summing circuit, wherein the summing circuit is configured to aggregate the first output of the at least one first-type switch current sensor subcircuit and the second output of the at least one second-type switch current sensor subcircuit to obtain a voltage waveform that is proportional to a switch current configured to flow in the conductor, the voltage waveform including a direct current (DC) component and steady-state alternating current (AC) components of the switch current, wherein the at least one first-type switch current sensor subcircuit comprises:
a first-type integrator circuit and an absolute value average detector circuit, which together are configured to produce the DC component of the switch current, and
wherein the at least one second-type switch current sensor subcircuit comprises:
a second coil having second coil output terminals,
a second coil termination having second coil termination terminals and coupled at the second coil termination terminals across the second coil output terminals,
a second-type integrator circuit having second-type integrator input terminals and a second-type integrator output terminal and coupled at the second-type integrator input terminals across the second coil output terminals, in parallel with the second coil termination,
a second DC canceling circuit having a second DC canceling circuit input and a second DC canceling circuit output and coupled at the second DC canceling circuit input to the second-type integrator output terminal and coupled at the second DC canceling circuit output to the summing circuit, and
at least one gain or bandwidth adjustment circuit having an adjustment circuit input and an adjustment circuit output, wherein the second DC canceling circuit output is coupled at the adjustment circuit input to the second DC canceling circuit output and at the adjustment circuit output to the summing circuit.

2 . The switch current sensor of claim 1 , wherein the at least one first-type switch current sensor subcircuit comprises:
a first coil having first coil output terminals; a first coil termination having first coil termination terminals and coupled at the first coil termination terminals across the first coil output terminals; the first-type integrator circuit having first-type integrator input terminals and a first-type integrator output terminal and coupled at the first-type integrator input terminals across the first coil output terminals, in parallel with the first coil termination; a first DC canceling circuit having a first DC canceling circuit input and a first DC canceling circuit output and coupled at the first DC canceling circuit input to the first-type integrator output terminal; and the absolute value average detector circuit having a detector circuit input and a detector circuit output and coupled at the detector circuit input to the first DC canceling circuit output and at the detector circuit output to the summing circuit.

3 . The switch current sensor of claim 2 , wherein the absolute value average detector circuit is at least one of:
a half-wave rectifier circuit, or a full-wave rectifier circuit.

4 . The switch current sensor of claim 2 , wherein the at least one second-type switch current sensor subcircuit comprises the second-type integrator circuit, and
the first-type integrator circuit is a non-inverting integrator circuit, the absolute value average detector circuit is an inverting absolute value average detector circuit, and the second-type integrator circuit is an inverting integrator circuit; or the first-type integrator circuit is the inverting integrator circuit, the absolute value average detector circuit is a non-inverting absolute value average detector circuit, and the second-type integrator circuit is the non-inverting integrator circuit.

5 . The switch current sensor of claim 2 , wherein the absolute value average detector circuit is configured to:
obtain, at the detector circuit input, the voltage waveform proportional to the switch current without the DC component of the switch current; and obtain, at the detector circuit output, the DC component of the switch current.

6 . The switch current sensor of claim 1 , wherein the at least one second-type switch current sensor subcircuit is a plurality of second-type switch current sensor subcircuits, and each of the plurality of second-type switch current sensor subcircuits is configured to sense a respective portion of a total switch current sensor frequency bandwidth.

7 . The switch current sensor of claim 6 , wherein each sensed respective portion of the total switch current sensor frequency bandwidth spans a respective bandwidth that is less than the total switch current sensor frequency bandwidth, and
an aggregated combination of respective outputs of the plurality of second-type switch current sensor subcircuits provides an aggregated bandwidth that is equal to the total switch current sensor frequency bandwidth.

8 . A switch current sensor, comprising:
means for summing; first means for sensing current having a first input and a first output to be configured to be coupled (M) at the first input to a conductor, and coupled at the first output to the means for summing; and second means for sensing current having a second input and a second output to be configured to be coupled (M) at the second input to the conductor and coupled at the second output to the means for summing, wherein the means for summing circuit is configured to aggregate the first output of the first means for sensing current and the second output of the second means for sensing current to produce a voltage waveform that is proportional to a switch current configured to flow in the conductor, the voltage waveform including a direct current (DC) component and steady-state alternating current (AC) components of the switch current, wherein the first means for sensing current comprises:
a first means for integrating and a means for absolute value average detecting, which together are configured to produce the DC component of the switch current, and
wherein the second means for sensing current comprises:
a second coil having second coil output terminals,
a second coil termination having second coil termination terminals and coupled at the second coil termination terminals across the second coil output terminals,
a second means for integrating having second means for integrating input terminals and a second means for integrating output terminal and coupled at the second means for integrating input terminals across the second coil output terminals, in parallel with the second coil termination,
second means for DC canceling having a second means for DC canceling input and a second means for DC canceling output and coupled at the second means for canceling input to the second means for integrating output terminal and coupled at the second means for DC canceling output to the means for summing, and
means for adjusting gain or bandwidth having a means for adjusting input and a means for adjusting output, wherein the second means for DC canceling output is coupled at the means for adjusting input to the second means for DC canceling output and at the means for adjusting output to the means for summ

Assignees

• Univ North Carolina Charlotte

Inventors

• Parsa Sirat Ali
• Niakan Hossein
• Parkhideh Babak

Classifications

• H01F38/32

  Circuit arrangements · CPC title

• G01R19/16547

  voltage or current in AC supplies (switching for protection H02H; circuits for emergency power supply H02J9/00) · CPC title

• G01R19/0046

  characterised by a specific application or detail not covered by any other subgroup of G01R19/00 · CPC title

• G01R15/181

  using coils without a magnetic core, e.g. Rogowski coils · CPC title

• H01F38/30 Primary

  Constructions · CPC title