Current sensor system

A method for determining a current in one or more of a plurality of conductors, the method comprising:

• providing a plurality of current sensors having a first number of current sensors, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field;
• providing a plurality of conductors having a second number of conductors, each configured to carry a current to be measured, wherein the second number is at least one less than the first number;
• for each magnetic field sensing element, characterizing a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors, wherein characterizing the magnetic coupling between the current sensor and each of the plurality of conductors comprises:
• determining a coupling factor indicative of a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors;
• and
• generating a coupling matrix comprising one or more coupling factors for each magnetic field sensing element;
• using the magnetic coupling characterization to determine the current in one or more of the plurality of conductors;
• extracting a best fit current vector [I] for a matrix equation A×I=H, where [A] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors;
• and
• solving the matrix equation A×I=H using a least squares method or a pseudo-inverse to thereby generate a matrix [C] such that I=C×H.

A current sensor system comprising:

• a plurality of current sensors having a first number of current sensors, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field;
• a plurality of conductors having a second number of conductors, each configured to carry a current to be measured, wherein the second number is at least one less than the first number;
• means for characterizing a magnetic coupling between each magnetic field sensing element and each of the plurality of conductors wherein the means for characterizing the magnetic coupling between the magnetic field sensing element and each of the plurality of conductors comprises:
• means for determining a coupling factor indicative of a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors;
• and
• means for generating a coupling matrix comprising one or more coupling factors for each magnetic field sensing element;
• means for using the magnetic coupling characterization to determine the current in one or more of the plurality of conductors;
• means for extracting a best fit current vector [I] for a matrix equation A×I=H, where [A] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors;
• and
• means for solving the matrix equation A×I=H using a least squares method or a pseudo-inverse to thereby generate a matrix [C] such that I=C×H.

A current sensor system comprising:

• a plurality of current sensors positioned proximate to a plurality of conductors each configured to carry a current to be measured, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field, wherein the plurality of current sensors includes a first number of current sensors and the plurality of conductors includes a second number of conductors such that the first number is at least one more than the second number, wherein the one or more magnetic field sensing elements of each of the plurality of current sensors has a maximum sensitivity in the same direction;
• and
• a controller coupled to receive the magnetic field signal from each of the plurality of current sensors, and, for each magnetic field sensing element, configured to characterize a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors, wherein, for each magnetic field sensing element, the controller is further configured to:
• determine a coupling factor indicative of a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors;
• and
• use the coupling factors to determine the current in one or more of the plurality of conductors;
• wherein the controller comprises a processor configured to generate a coupling matrix [D] comprising the coupling factors for each of the plurality of magnetic field sensing elements and stray field coefficients, wherein the processor is further configured to extract a best fit vector [J] for a matrix equation D×J=H, where [D] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors, wherein the processor is further configured to solve the matrix equation D×J=H using an inversion method or a least squares method or pseudo-inverse to generate a matrix [F] such that J=F×H.

A current sensor system comprising:

• a plurality of current sensors positioned proximate to a plurality of conductors each configured to carry a current to be measured, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field, wherein the plurality of current sensors includes a first number of current sensors and the plurality of conductors includes a second number of conductors such that the first number is at least one more than the second number, wherein the one or more magnetic field sensing elements of each of the plurality of current sensors has a maximum sensitivity in the same direction;
• and
• a controller coupled to receive the magnetic field signal from each of the plurality of current sensors, and, for each magnetic field sensing element, configured to characterize a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors, wherein, for each magnetic field sensing element, the controller is further configured to:
• determine a coupling factor indicative of a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors;
• and
• use the coupling factors to determine the current in one or more of the plurality of conductors;
• wherein the controller comprises a processor configured to generate a coupling matrix [D] comprising the coupling factors for each of the plurality of magnetic field sensing elements and stray field coefficients, wherein the processor is further configured to extract a best fit vector [J] for a matrix equation D×J=H, where [D] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors, wherein the processor is further configured to compare an evaluated stray field value from the best fit vector [J] to a threshold value.

A method for determining a current in one or more of a plurality of conductors, the method comprising:

• providing a plurality of current sensors having a first number of current sensors, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field, wherein the one or more magnetic field sensing elements of each of the plurality of current sensors has a maximum sensitivity in the same direction;
• providing a plurality of conductors having a second number of conductors, each configured to carry a current to be measured, wherein the second number is at least one less than the first number;
• for each magnetic field sensing element, characterizing a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors, wherein characterizing the magnetic coupling between the current sensor and each of the plurality of conductors comprises:
• determining a coupling factor indicative of a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors;
• and
• generating a coupling matrix comprising one or more coupling factors for each magnetic field sensing element;
• using the magnetic coupling characterization to determine the current in one or more of the plurality of conductors;
• generating a coupling matrix [D] comprising the coupling factors for each magnetic field sensing element and stray field coefficients;
• extracting a best fit vector [J] for a matrix equation D×J=H, where [D] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors;
• and
• solving the matrix equation D×J=H using an inversion method or a least squares method or a pseudo-inverse to generate a matrix [F] such that J=F×H.

A method for determining a current in one or more of a plurality of conductors, the method comprising:

• providing a plurality of current sensors having a first number of current sensors, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field, wherein the one or more magnetic field sensing elements of each of the plurality of current sensors has a maximum sensitivity in the same direction;
• providing a plurality of conductors having a second number of conductors, each configured to carry a current to be measured, wherein the second number is at least one less than the first number;
• for each magnetic field sensing element, characterizing a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors, wherein characterizing the magnetic coupling between the current sensor and each of the plurality of conductors comprises:
• determining a coupling factor indicative of a magnetic coupling between the magnetic field sensing element and each of the plurality of conductors;
• and
• generating a coupling matrix comprising one or more coupling factors for each magnetic field sensing element;
• using the magnetic coupling characterization to determine the current in one or more of the plurality of conductors;
• generating a coupling matrix [D] comprising the coupling factors for each magnetic field sensing element and stray field coefficients;
• extracting a best fit vector [J] for a matrix equation D×J=H, where [D] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors;
• comparing an evaluated stray field value from the best fit vector [J] to a threshold value;
• and
• outputting a diagnostic status when the evaluated stray field value exceeds the threshold value.

A current sensor system comprising:

• a plurality of current sensors having a first number of current sensors, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field, wherein the one or more magnetic field sensing elements of each of the plurality of current sensors has a maximum sensitivity in the same direction;
• a plurality of conductors having a second number of conductors, each configured to carry a current to be measured, wherein the second number is at least one less than the first number;
• means for characterizing a magnetic coupling between each magnetic field sensing element and each of the plurality of conductors;
• and
• means for using the magnetic coupling characterization to determine the current in one or more of the plurality of conductors;
• means for generating a coupling matrix [D] comprising the coupling factors for each magnetic field sensing element and stray field coefficients;
• means for extracting a best fit vector [J] for a matrix equation D×J=H, where [D] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors;
• and
• means for solving the matrix equation D×J=H using an inversion method or a least squares method or a pseudo-inverse to generate a matrix [F] such that J=F×H.

A current sensor system comprising:

• a plurality of current sensors having a first number of current sensors, each current sensor comprising one or more magnetic field sensing elements configured to generate a respective magnetic field signal indicative of a detected magnetic field, wherein the one or more magnetic field sensing elements of each of the plurality of current sensors has a maximum sensitivity in the same direction;
• a plurality of conductors having a second number of conductors, each configured to carry a current to be measured, wherein the second number is at least one less than the first number;
• means for characterizing a magnetic coupling between each magnetic field sensing element and each of the plurality of conductors;
• and
• means for using the magnetic coupling characterization to determine the current in one or more of the plurality of conductors;
• means for generating a coupling matrix [D] comprising the coupling factors for each magnetic field sensing element and stray field coefficients;
• means for extracting a best fit vector [J] for a matrix equation D×J=H, where [D] is the coupling matrix and [H] is a matrix comprising the magnetic field signals from the plurality of current sensors;
• and
• means for comparing an evaluated stray field value from the best fit vector [J] to a threshold value;
• and
• means for outputting a diagnostic status when the evaluated stray field value exceeds the threshold value.