CN-121995280-A - Temperature compensation method of fluxgate sensor integrating temperature monitoring and self-checking functions

Abstract

A temperature compensation method of a fluxgate sensor integrating temperature monitoring and self-checking functions comprises the steps of 1, temperature calibration, multi-temperature-point magnetic field calibration and data acquisition, 3, embedded model and real-time compensation, 4, outputting a final result, solving the technical problems of low integration level, complex calibration and large temperature drift error of a traditional fluxgate sensor system, and integrating a convenient and reliable self-checking mechanism.

Inventors

• LI BIN
• YANG JUAN
• YANG CHANGHONG
• XIANG PENGFEI
• GAO XINGANG

Assignees

• 西安华舜测量设备有限责任公司

Dates

Publication Date

20260508

Application Date

20260209

Claims (3)

1. 1.A method for temperature compensation of a fluxgate sensor integrating temperature monitoring and self-checking functions, comprising the steps of: Step 1, temperature calibration: A first function model of temperature correction of the sensor, a second function model of zero drift about temperature and a third function model of sensitivity about temperature are established in advance through multi-temperature point calibration; step 2, calibrating magnetic fields with multiple temperature points and collecting data: The parameters of the first function model, the second function model and the third function model are stored in a memory of the sensor, and when the sensor works, an environment temperature value and an original output value are obtained in real time; Step 3, embedded model and real-time compensation: Calculating a current actual temperature correction value by using a first function model according to the environmental temperature value, calculating a current zero drift estimated value by using the second function model, and calculating a current sensitivity estimated value by using the third function model; step 4, outputting a final result: And compensating the original output value by using the temperature correction value, the current zero drift estimated value and the current sensitivity estimated value to obtain an accurate magnetic field measured value.
2. 2. The method for temperature compensation of a fluxgate sensor integrated with temperature monitoring and self-checking functions according to claim 1, wherein the first, second and third function models are second or third order polynomial functions, and the first, second and third function models are piecewise linear functions.
3. 3. The method for temperature compensation of a fluxgate sensor integrating temperature monitoring and self-checking functions according to claim 1, wherein the step of compensating for the original output value is implemented by the following formula: B_compensated = (V_raw - V_offset_est(T)) / S_est(T) Wherein b_compensated is the magnetic field value after compensation, v_raw is the original output value, v_offset_est (T) is the zero drift estimate calculated from the current corrected temperature T, and s_est (T) is the sensitivity estimate calculated from the current corrected temperature T.

Description

Temperature compensation method of fluxgate sensor integrating temperature monitoring and self-checking functions Technical Field The invention belongs to the technical field of fluxgate sensors, and particularly relates to a temperature compensation method of a fluxgate sensor integrating temperature monitoring and self-checking functions. Background The fluxgate sensor is a high-precision magnetic field measuring instrument based on the magnetic saturation principle, has the advantages of wide measuring range, high resolution, good stability and the like, and is widely applied to the fields of geophysical exploration, space magnetic field detection, industrial nondestructive detection, navigation systems, biomedicine and the like. With the development of technology, the performance requirements of fluxgate sensors are increasing, especially in terms of long-term stability, reliability and field maintainability. However, conventional fluxgate sensors still face two significant technical bottlenecks in practical applications: (1) The system has high complexity, the sensor outputs an analog voltage signal, and a user is required to design additional data acquisition equipment (comprising an analog filter circuit, an ADC sampling circuit, an MCU and the like) to carry out digital processing, so that the complexity of the system design is increased. When the sensor is matched with data acquisition equipment designed by a user, complex electromagnetic compatibility problems can be generated. (2) The parameter calibration is complex, the fluxgate sensor and the matched data acquisition equipment are subjected to system cascade adjustment calibration, the key parameters such as sensitivity, zero offset and the like obtained by calibration are required to be solidified and stored in a nonvolatile memory of the data acquisition equipment, the serial number of each sensor and the serial number of the data acquisition equipment are required to be in one-to-one correspondence, if the sensor is connected with the unpaired acquisition equipment, the original calibration parameters are invalid, and the system calibration is required to be performed again, so that the measurement accuracy and the data validity can be ensured. (3) An inherent disadvantage of analog signal links is that long-range transmission of analog signals is susceptible to electromagnetic interference, resulting in a reduced signal-to-noise ratio. The links such as an analog integrator have the problem of integral drift, and the long-term stability is affected. Furthermore, analog systems do not facilitate nonlinear correction and advanced algorithmic processing, limiting further improvement in sensor performance. (4) Temperature drift problems the physical and electrical parameters of the core sensing element (e.g., magnetic core) and signal conditioning circuitry (e.g., oscillator, amplifier, phase sensitive detector, etc.) of fluxgate sensors are very sensitive to changes in ambient temperature. The temperature fluctuation can directly cause drift of magnetic permeability, coercive force, inductance and resistance of a coil and performance of a semiconductor component. These variations eventually manifest themselves as zero drift and sensitivity drift of the sensor output signal, collectively referred to as temperature drift, which are the most significant factors affecting fluxgate sensor measurement accuracy and long term stability. The fluxgate sensor inevitably undergoes temperature change in the actual working environment, and the system cannot effectively perform real-time temperature compensation because the temperature of the core part (particularly the magnetic core) of the sensor cannot be sensed accurately in real time. Therefore, the output signal contains temperature errors which cannot be distinguished and eliminated, so that the measured data is unreliable in a high-precision application scene. And when the sensor output drifts, as no temperature data is used as a reference, operation and maintenance personnel can not quickly judge whether the sensor is caused by external magnetic field change, the sensor self fault or simple environmental temperature influence, great difficulty is brought to fault detection and system state monitoring, and the overall reliability of the system is reduced. (5) The magnetic flux gate sensor is used as a key measuring device, and the health of the working state of the magnetic flux gate sensor is very important. Particularly in the safety critical fields of aerospace, unmanned systems and the like, the sensor needs to be ensured to be always in a normal state. However, most existing fluxgate sensors do not have online self-test capability. An operator or system cannot quickly diagnose whether the sensor is malfunctioning without powering down or dismantling. The existing detection method generally depends on periodic off-line calibration or factory return detection, which is complex in flow, time-consu