Method for operating a resonance-measuring system and respective resonance system

Patent metadata

Field	Value
Publication number	US-10151728-B2
Application number	US-201314419323-A
Country	US
Kind code	B2
Filing date	Jun 17, 2013
Priority date	Jun 18, 2012
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

A method for operating a resonant measurement system has at least one: adjustment device, electric actuation device, electromagnetic vibration generator, vibrating element, and vibration recorder. The adjustment device generates an output signal to trigger the electric actuation device, the electric actuation device provides an electric excitation signal to the electromagnetic drive, the electromagnetic drive excites the vibrating element to the same vibration in at least one normal mode, and the excited vibration is sensed by the vibration recorder and is output as an output signal. To approach, maintain and readjust a resonant point as an operating point of the resonant measurement system, the phase difference between the output signal of the vibration recorder and the adjustment device output signal is acquired, an adjustment deviation is calculated from a predefined phase difference and the acquired phase difference, and the adjustment deviation provided to the adjustment device as an input signal.

First claim

What is claimed is:

1. Method for operating a resonance-measuring system having at least one controller, at least one electric setting device, at least one electromagnetic drive with a drive coil, at least one oscillation element and at least one oscillation sensor, comprising the steps of:
using said at least one controller to generate a controller output signal u 1 for controlling the electric setting device, wherein the at least one electric setting device provides a voltage u s as an electric excitation signal u 2 for exciting the electromagnetic drive, and wherein the voltage u 2 is applied as a terminal voltage of the drive coil of the electromagnetic drive,
using the electric setting device to provide an electric excitation signal u 2 for exciting the electromagnetic drive,
using the electromagnetic drive to excite the oscillation element into oscillation in at least one natural mode,
detecting the excited oscillation of the oscillation element with the oscillation sensor and outputting the detected excited oscillation as at least one output signal y based on the excited oscillation detected,
using an electronic circuit for determining a controller-oscillation-sensor-phase-difference between the output signal of the oscillation sensor and the controller output signal u 1 in a control loop on the basis of the output signal and a measured controller output signal,
using a digital signal processor for calculating a control deviation e using a predetermined phase difference and the determined controller-oscillation-sensor-phase-difference,
separately determining a controller-drive-phase-difference on the basis of the measured controller output signal u_ 1 and a measured current in the coil of the electromagnetic drive, and using the controller-drive-phase-difference Δφ(i s , u 1 ) as the predetermined phase difference, and
providing the control deviation to the controller as an input signal of a control loop for ongoing control of the electric setting device so to adjust excitation of the oscillation element into oscillation close to the resonance point of the resonance-measuring system based on the controller-oscillation-sensor-phase difference.

2. Method according to claim 1 , wherein the predetermined phase difference is chosen such that the oscillation element is excited to oscillation in at least one natural mode in resonance or near a point of resonance.

3. Method according to claim 1 , wherein the determined controller-drive-phase-difference is filtered with a low-pass filter having a time constant in a seconds range.

4. Method according to claim 3 , wherein a harmonic base signal is generated by the controller as the controller output signal u 1 for determining at least one of the controller-oscillation-sensor-phase-difference and the controller-drive-phase-difference Δφ(i S , u 1 ), wherein each phase difference is determined using demodulation of each signal y, i s of interest with the harmonic base signal and a further harmonic base signal, orthogonal to the first harmonic base signal, provided by the controller.

5. Method according to claim 1 , wherein one of mass flow rate, density and fill level is determined from an output of the system.

6. Resonance-measuring system, comprising:
an electromagnetic drive,
at least one controller,
at least one electric setting device,
at least one oscillation element, and
at least one oscillation sensor,
wherein the controller is configured for generating a controller output signal for controlling the electric setting device,
wherein the electric setting device is adapted to provide an electric excitation signal for exciting the electromagnetic drive,
wherein the electromagnetic drive is configured for exciting the oscillation element into oscillation in at least one natural mode,
wherein the oscillation sensor is configured for detecting excited oscillation of the oscillation element and for outputting at least one output signal, and
wherein a control loop is formed on the basis of the output signal and the controller output signal in such a manner that a controller-oscillation-sensor-phase-difference between the output signal of the oscillation sensor and the controller output signal determined on the basis of the controller output signal and the current in the coil of the electromagnetic drive and controls the electric setting device so to adjust excitation of the oscillation element into oscillation close to the resonance point of the resonance-measuring system.

7. Resonance-measuring system according to claim 6 , wherein the electric setting device is a voltage-controlled voltage transformer.

8. Resonance-measuring system according to claim 6 , wherein the system is a Coriolis mass flowmeter.

9. Method for operating a resonance-measuring system having at least one controller, at least one electric setting device, at least one electromagnetic drive with a drive coil, at least one oscillation element and at least one oscillation sensor, comprising the steps of:
using said at least one controller to generate a controller output signal for controlling the electric setting device,
using the electric setting device to provide an electric excitation signal for exciting the drive coil of the electromagnetic drive, wherein the electric setting device provides a voltage us as an electric excitation signal for exciting the electromagnetic drive, and wherein the voltage us is applied as a terminal voltage of the drive coil of the electromagnetic drive,
using the electromagnetic drive to excite the oscillation element into oscillation in at least one natural mode,
detecting the excited oscillation of the oscillation element with the oscillation sensor and outputting the detected excited oscillation as at least one output signal y based on the excited oscillation detected,
using an electronic circuit for determining a controller-oscillation-sensor-phase-difference between the output signal of the oscillation sensor and the controller output signal u 1 in a control loop on the basis of the output signal and a measured controller output signal,
using a digital signal processor for calculating a control deviation e using a predetermined phase difference and the determined controller-oscillation-sensor-phase-difference,
determining a controller-drive-phase-difference between a state variable of the electromagnetic drive and the controller output signal on the basis of the measured controller output signal and a measured current in the coil of the electromagnetic drive,

and separately calculating the predetermined phase difference Δφ S1 using the determined controller-drive-phase-difference and an additional predetermined phase difference Δφ S2 ,
using the current of the drive coil as the state variable of the electromagnetic drive,
providing the control deviation to the controller as an input signal of a control loop for ongoing control of the electric setting device so to adjust excitation of the oscillation element into oscillation close to the resonance point of the resonance-measuring system.

10. Method according to claim 9 , wherein the determined controller-drive-phase-difference is filtered with a low-pass filter having a time constant in a seconds range.

11. Method according to claim 9 , wherein a harmonic base signal is generated by the controller as the controller output signal for determining at least one of the controller-oscillation-sensor-phase-difference and the controller-drive-phase-difference, wherein each phase difference is determined using demodulation of each signal, is of interest with the harmonic base signal and a further harmonic base signal, orthogonal to the first harmonic base signal, prov

Assignees

• Krohne Messtechnik Gmbh

Inventors

• Kolahi Kourosh
• Storm Ralf
• Poremba Andreas

Classifications

• G01F1/8436

  signal processing · CPC title

• G01F1/8468

  vibrating measuring conduits · CPC title

• G01N11/10

  by moving a body within the material · CPC title

• G01F1/8422 Primary

  exciters · CPC title

• G01F1/8431

  electronic circuits · CPC title