Magnetic Inductive Flow Meter Electrode Voltage Correction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Magnetic-inductive flow meters experience time losses due to the need to wait for a steady state after changes in magnetic field polarity or between phases, which reduces the available time for flow measurement.

Innovation Solution

A method that involves setting up a rest phase during feed phase changes to detect and correct electrode voltage disturbances, using a fit function to analyze voltage pulses from rest phases to determine and correct for interference, allowing for immediate use of electrode voltage measurements during transient phases for flow calculation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a rest phase is set up during feed phase changes to detect and correct electrode voltage disturbances, then measurement precision is improved, but loss of time increases due to the additional rest phase

Engineering Contradiction:
Improveelectrode voltage measurement accuracyVSAvoidtime loss during phase transitions
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by performing disturbance detection and characterization during rest phases before actual feed phase measurements. The system uses rest phases to pre-determine disturbance characteristics (offsets, gains, time constants) that are then compensated for during subsequent feed phase measurements, improving precision without sacrificing measurement time.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent converts the harmful effect of transient disturbances during phase transitions into a beneficial measurement opportunity. By intentionally creating rest phases where disturbances can be cleanly observed and characterized without flow interference, the system transforms measurement contamination into a source of calibration data that improves overall measurement accuracy.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

2Productivity

If electrode voltage measurements are used during transient phases, then productivity is improved by reducing time losses, but measurement precision deteriorates due to disturbances

Engineering Contradiction:
Improveflow measurement availabilityVSAvoidelectrode voltage accuracy during transients
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The patent implements feedback by using disturbance characteristics measured during rest phases to dynamically correct electrode voltage measurements taken during feed phases. The system continuously updates compensation parameters based on rest phase observations and applies these corrections to feed phase measurements, enabling accurate measurements during previously unusable transient periods.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The patent applies parameter changes by dynamically adjusting measurement compensation parameters (offsets, gains, time constants) based on conditions observed during rest phases. The system modifies how electrode voltages are interpreted during feed phases by applying corrections derived from rest phase disturbance characterization, enabling accurate measurements during transient conditions.

Inventive Principle:
Principle #35Parameter changes

3Loss of time

If the duration of feed phases is reduced to minimize time losses, then loss of time decreases, but measurement precision worsens due to insufficient steady state establishment

Engineering Contradiction:
Improvetime loss waiting for steady stateVSAvoidflow measurement accuracy
Core Design Contradiction:
Loss of timeVSMeasurement precision

Solution Approach 1:

The patent applies preliminary action by pre-characterizing disturbance parameters during rest phases before feed phase measurements begin. This advance preparation allows the system to use shorter feed phases because the compensation parameters are already determined, eliminating the need to wait for complete steady state establishment while maintaining measurement precision.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent enables continuous useful action by removing the idle waiting period for steady state establishment. By applying disturbance compensation based on rest phase measurements, the system can continuously perform accurate flow measurements during feed phases without interruption or waiting, maximizing productivity while maintaining precision.

Inventive Principle:
Principle #20Continuity of useful action

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

This approach minimizes time losses by enabling the use of electrode voltage measurements during transient phases, improving the signal-to-noise ratio and reducing the duration of feed phases available for flow measurement.

Implementation Method 1

a magnet system with at least one coil system for generating a magnetic field in the medium, the magnetic field being essentially perpendicular to a measuring tube axis, the magnetic field being produced by applying an electrical coil voltage to the coil system

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

at least one pair of measuring electrodes arranged in the measuring tube for detecting an electrode voltage induced by the magnetic field in the medium, which electrode voltage is essentially proportional to the flow rate and to the field strength of the magnetic field, the electrode voltage being caused by charge carrier separation, which is caused by the flow of the medium through the magnetic field

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP3559603B1Method for operating a magnetic/inductive flow meter and magnetic/inductive meter
Publication Date: 2021.08.25 ENDRESS HAUSER FLOWTEC AG
  • EP3559603B1 patent drawingFigure 1
  • EP3559603B1 patent drawingFigure 2
  • EP3559603B1 patent drawingFigure 3

AI summary

The invention relates to a method (100) for operating a magnetic/inductive flow meter for measuring the flow rate or the volumetric flow of a medium in a measuring tube (10) and to such a flow meter, wherein the medium is acted upon by magnetic fields of different polarity and field strength, wherein the alternation between magnetic fields causes a voltage pulse in the medium, wherein a voltage pulse during a phase without a magnetic field is used for calculation of a correction of an electrode voltage characteristic.