FPGA Fluxgate Current Transducer for Compact Precision Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Fluxgate current transducers are costly and require complex microcontrollers like DSPs, making them less compact and less cost-effective compared to Hall effect detectors, despite their high sensitivity and accuracy.
Innovation Solution
A fluxgate current transducer utilizing a Field Programmable Gate Array (FPGA) with 1 bit sigma delta analog-to-digital converters and digital-to-analog converters to simplify the control circuit, reducing the need for microcontrollers and enabling cost-effective, accurate, and compact design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a microcontroller (DSP) is used to control the fluxgate current transducer, then the measurement performance and accuracy are improved, but the device complexity and manufacturing cost increase
Solution Approach 1:
The patent extracts the essential control functions from a complex DSP microcontroller and implements them using a simplified controller with dedicated hardware circuits. The excitation signal generator, ADC, and compensation logic are implemented as separate functional blocks rather than requiring a full-featured microcontroller, thereby reducing device complexity while maintaining measurement accuracy.
Solution Approach 2:
The patent replaces expensive DSP microcontrollers with a more economical controller implementation using basic digital logic and simple processing units. This substitution reduces manufacturing cost and device complexity while achieving the same measurement precision through optimized circuit design rather than relying on high-performance general-purpose processors.
2Measurement precision
If a DSP microcontroller is used in the fluxgate current transducer, then the signal processing capability is improved, but the transducer size and cost increase
Solution Approach 1:
The patent merges multiple functions (excitation signal generation, analog-to-digital conversion, compensation current control, and measurement processing) into a single integrated controller unit. This consolidation eliminates the need for separate DSP microcontroller and its associated support circuits, reducing the overall circuit board area while maintaining full signal processing capability.
Solution Approach 2:
The simplified controller is designed to perform multiple functions: generating excitation signals, converting analog measurements to digital values, controlling compensation current, and processing measurement data. This multi-functional design replaces the need for a specialized DSP microcontroller, reducing the required circuit board area while preserving all necessary signal processing capabilities.
3Productivity
If a high-performance microcontroller is used, then the real-time measurement capability is improved, but the manufacturing cost and device complexity increase
Solution Approach 1:
The controller is designed to autonomously generate excitation signals, perform analog-to-digital conversion, and execute compensation algorithms without requiring external high-performance processing. The system serves itself by integrating all necessary functions into a single cost-effective controller unit, achieving real-time measurement capability without the need for expensive DSP microcontrollers.
Solution Approach 2:
The patent replaces the electronic processing system (DSP microcontroller) with a simplified controller architecture using dedicated hardware circuits and basic digital logic. This substitution maintains real-time measurement capability through optimized circuit design while significantly reducing manufacturing cost and device complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The FPGA-based design achieves rapid startup, high precision, and stable measurement accuracy with reduced noise and drift, allowing for easy calibration and configuration, while being compact and cost-effective.
Implementation Method 1
the fluxgate magnetic field detector comprising a saturable soft magnetic core surrounded by an excitation coil, the control circuit comprising an excitation coil drive circuit connected to the excitation coil and a controller connected to the excitation coil drive circuit configured to generate an alternating excitation current Ifx to alternatingly saturate the soft magnetic core
Implementation Method 2
the controller is in the form of a FPGA (Field Programmable Gate Array) comprising at least one input comprising a 1 bit sigma delta analog-to-digital converter (ADC) connected to the excitation coil to receive a measurement signal output by the excitation coil
Data Source
AI summary
Fluxgate current transducer including a control circuit and a fluxgate measuring device comprising a fluxgate magnetic field detector, the fluxgate magnetic field detector comprising a saturable soft magnetic core surrounded by an excitation coil, the control circuit comprising an excitation coil drive circuit connected to the excitation coil and a controller connected to the excitation coil drive circuit configured to generate an alternating excitation current Ifx to alternatingly saturate the soft magnetic core. The controller is in the form of a FPGA (Field Programmable Gate Array) comprising at least one input comprising a 1 bit sigma delta analog-to-digital converter (ADC) connected to the excitation coil to receive a measurement signal output by the excitation coil.