Patent classifications
G01R33/0206
3D MEMS MAGNETOMETER AND ASSOCIATED METHODS
A micro-electro-mechanical system (MEMS) magnetometer is provided for measuring magnetic field components along three orthogonal axes. The MEMS magnetometer includes a top cap wafer, a bottom cap wafer and a MEMS wafer having opposed top and bottom sides bonded respectively to the top and bottom cap wafers. The MEMS wafer includes a frame structure and current-carrying first, second and third magnetic field transducers. The top cap, bottom cap and MEMS wafer are electrically conductive and stacked along the third axis. The top cap wafer, bottom cap wafer and frame structure together form one or more cavities enclosing the magnetic field transducers. The MEMS magnetometer further includes first, second and third electrode assemblies, the first and second electrode assemblies being formed in the top and/or bottom cap wafers. Each electrode assembly is configured to sense an output of a respective magnetic field transducer induced by a respective magnetic field component.
Magnetic sensor device and magnetic sensor system
A magnetic sensor device includes at least one magnetic sensor and a support. A center of gravity of an element layout area of the at least one magnetic sensor is deviated from a center of gravity of a reference plane of the support. The at least one magnetic sensor includes four resistor sections constituted by a plurality of magnetoresistive elements. Magnetization of a free layer in each of two of the resistor sections includes a component in a third magnetization direction. The magnetization of a free layer in each of the other two resistor sections includes a component in a fourth magnetization direction opposite to the third magnetization direction.
DUAL Z-AXIS MAGNETORESISTIVE ANGLE SENSOR
A dual Z-axis magnetoresistive angle sensor comprising a circular permanent magnet encoding disc, two Z-axis magnetoresistive senor chips, and a PCB, two Z-axis magnetoresistive sensors are placed on the PCB. The magnetic sensing directions of the Z-axis magnetoresistive sensors are orthogonal to the substrate. Each Z-axis magnetoresistive sensor chip comprises a substrate and at least one magnetoresistive sensor located on the substrate. The magnetic field sensitive direction of the magnetoresistive sensor is perpendicular to the substrate. The magnetoresistive sensor comprises a flux concentrator and a magnetoresistive sensor unit. The magnetoresistive sensor unit is connected electrically into a push-pull structure. The push arm and pull arm of the magnetoresistive sensor are respectively located at two side positions equidistant from Y-axis central line and above or below the flux concentrator. The circular permanent magnet encoding disc has a magnetization direction parallel to the diameter direction. When the circular permanent encoding disc rotates, a magnetic field measurement angle is calculated via orthogonal magnetic fields measured by the two z-axis magnetoresistive sensor chip. The magnetic field measurement angle can be used for representing a rotation angle of the circular permanent magnetic encoding disc. This dual Z-axis magnetoresistive angle sensor's structure is simple, and it also has the characteristics of high sensitivity and high spatial flexibility.
Triaxial coil sensor and magnetic field measuring device including the same
Provided is a magnetic field measuring device including a first sensor unit which includes a first coil sensor configured to output a first sensor signal, a second sensor unit which includes a second coil sensor configured to output a second sensor signal and disposed in a direction perpendicular to the first coil sensor, a third sensor unit which includes a third coil sensor configured to output a third sensor signal and disposed in a direction perpendicular to the first and second coil sensors, and a digital signal processor outputs magnetic flux density based on a voltage difference between the first and fourth nodes, wherein the first to third sensor units respectively output first to third output signals in which specific voltages of the first to third sensor signals are maintained for a predetermined period of time.
Condition monitoring device and method for monitoring an electrical machine
The present invention relates to a condition monitoring device and method for monitoring an electrical machine. The method includes obtaining, at periodic instants, measurements from sensors of the condition monitoring device, where each sensor is one of a magnetometer and an accelerometer. The method also includes comparing, for one or more instants, amplitude data of the measurements with condition monitoring data, wherein the comparison is performed for the amplitude data in one or more axes and at one or more frequencies. The condition monitoring data includes a relation between a plurality of parameters, a plurality of conditions and a plurality of frequencies. The method additionally includes detecting a condition and at least one parameter associated with the condition, based on the comparison. According to the detection, the method includes utilizing the measurements of the at least one parameter for determining a health condition of the electrical machine.
Magnetic Field Sensor with Integrated Field Concentrators
A one-dimensional magnetic field sensor comprises a support, a single elongated magnetic field concentrator or two magnetic field concentrators, which are separated by a first gap, and at least one magnetic sensor element. The magnetic field concentrator, or both thereof, consists of at least two parts which are separated from each other by second gaps. A two-dimensional magnetic field sensor comprises a support, a single magnetic field concentrator which consists of at least three parts which are separated from each other by gaps, and at least two magnetic sensor elements.
HYBRID HALL-EFFECT/MAGNETORESISTANCE (MR) MAGNETOMETER WITH SELF-CALIBRATION
Embodiments are disclosed for various configurations of a hybrid Hall/MR magnetometer with self-calibration. In an embodiment, a method comprises: a circuit coupled to a magnetometer and configured to determine whether the magnetometer is to operate in a sensing operation mode or a self-calibration operation mode. The magnetometer comprises a Hall sensor and MR sensor coupled to the circuit. In accordance with determining a sensing operation mode, the Hall sensor is turned and the MR sensor is turned on; and an external magnetic field is measured using the MR sensor. The magnetic field measurement is calibrated using a MR sensor bias error determined in a self-calibration operation mode of the sensor.
Dual magnetometer calibration
Examples of systems and methods for calibrating or operating a magnetic sensor for sensor temperature or operating conditions are provided. The magnetic sensor can comprise a dual magnetometer sensor that comprises a first, low-power-consumption magnetometer (e.g., a magneto-inductive magnetometer) and a second higher-power-consumption magnetometer (e.g., a magneto-resistive magnetometer). The second magnetometer can have a lower unit-to-unit variation in temperature calibration parameters and can be used to temperature-correct readings from the first magnetometer. The magnetic sensor can dynamically switch between usage of the first magnetometer and the second magnetometer in order to provide a dynamic sample rate that can depend on conditions within the sensor or external to the sensor.
Position detection device, signal processing circuit, and magnetic sensor system
A magnetic sensor system includes a magnetic sensor device and a signal processing circuit. The magnetic sensor device generates first to third detection signals corresponding to components in three directions a field generated by a magnetic field generator that is able to change its relative position with respect to the magnetic sensor device. The signal processing circuit includes first and second processors. The second processor generates sphere information and transmits it to the first processor. When coordinates representing a set of values of the first to third detection signals in an orthogonal coordinate system are taken as a measurement point, the sphere information includes data on center coordinates of a virtual sphere having a spherical surface approximating a distribution of a plurality of measurement points. The first processor detects a change in offsets of the first to third detection signals by using the sphere information transmitted from the second processor.
Method for Measuring Phase Currents of a Device Under Test, in Particular of an Inverter
A method is for measuring phase currents of a device under test, in particular of an inverter, in which a sensor arrangement, which has a component including a crystal lattice with a defect, is arranged in a region of the device under test. The method includes using the sensor arrangement to detect a magnetic field formed by a vector of magnetic fields, the magnetic fields each in turn being brought about by one of the phase currents of the device under test, and calculating a vector of the phase currents from the vector of the magnetic fields based on a coefficient matrix.