WO2019081600A1

WO2019081600A1 - Model-based determination and evaluation of functional states of a sensorless electromagnetic actuator

Info

Publication number: WO2019081600A1
Application number: PCT/EP2018/079204
Authority: WO
Inventors: Rolf Hermann; Nail Sabitov; Vladimir Kireev
Original assignee: Ilmenauer Mechatronik GmbH
Priority date: 2017-10-25
Filing date: 2018-10-24
Publication date: 2019-05-02
Also published as: DE102017125005B3

Abstract

The invention relates to a method for model-based determination and evaluation of functional states of a sensorless electromagnetic actuator (3) with at least one movable armature (4), the method comprising the following steps: - providing a reference characteristic curve (K1), - detecting a current i(t) and a voltage u(t) of an exciter circuit (8) of the electromagnetic actuator (3), - calculating at least one modelled characteristic curve (K1') by means of a model (11) and the at least one reference characteristic curve (K1), wherein the model (11) forms the at least one modelled characteristic curve (K1') by an adaptation with at least one hysteresis modelling (M1) depending on the measured current i(t) and the measured voltage u(t) of the reference characteristic curve (K1), and - evaluating and determining the functional states by comparing the measurement signals (i(t), u(t)) with the at least one modelled characteristic curve (K1').

Description

Model-based identification and evaluation of functional competent ^¬ a sensorless electromagnetic actuator

The invention relates to a method for model-based Be ^¬ humor and evaluation of functional states of a sensorlo ^¬ sen electromagnetic actuator, in particular a complex, electromagnetic actuator, and a device for operating at least of such a sensor-less electromagnetic

Actor.

Electromagnetic actuators are known from the prior art in different embodiments. Often, electromagnetic actuators are equipped with sensors that are used for functional testing. Such a

Electromagnetic actuator is previously known for example from DE 10 2009 042 777 AI, which has a current measuring device and a magnetic field sensor. During operation of the electromagnetic actuator, the measured data are compared with stored values of a characteristic to determine an anchor position.

DE 10 2011 075 935 B4 discloses a method and an on ^¬ direction for the determination of functional states of an electro ^¬ magnetic actuator, through the test sensorless Funktionsüber- of the electromagnetic actuator is realized which, upon detection and analysis of measurement data for Feldgrö ^¬ SEN , such as a magnetic flux density or a magnetic field strength, verz waives. For this purpose, the ^chain- linked magnetic flux is detected by means of the current and voltage measurement in the excitation circuit of the magnetic field, and functional states are determined on the basis of a comparison between a magnetic reference characteristic curve and an actual characteristic curve. A method and apparatus for operating a elekt ^¬ romagnetischen actuator are known from DE 10 2008 054 877 AI before ^¬ known, comprising a mathematical model which with ^¬ means of the measured in the exciter circuit current and voltage values information about a motion and / or expansion

determined.

A disadvantage of this prior art is that electromagnetic actuators have te sensorbasier ^¬ a great need for installation space and additional connection lines for the sensor or sensors are required. Sensors are sensitive to environmental and operating conditions and are therefore error-prone.

Sensorless electromagnetic actuators, on the other hand, allow a reduction in the required installation space, but such systems are often sensitive to environmental and environmental factors

Operating conditions of the electromagnetic actuator and are susceptible to errors, especially with regard to wear.

The aim of the present invention is to provide a method for the model-based determination and evaluation of

Functional states of a sensorless electromagnetic

Actuator, in particular a complex, electromagnetic actuator, and a device for operating at least one such sensorless electromagnetic actuator

to provide the relevant operating sizes of the

electromagnetic actuator by comparing the

Measured quantities current and voltage can be determined with a stored in a control and evaluation unit model of the electromagnetic actuator without the use of a sensor.

The inventive method for model-based determination and evaluation of functional states of a sensorless elekt ^¬ romagnetischen actuator, in particular a complex, electro ^¬ magnetic actuator with the features of claim 1, has compared to the prior art has the advantage that a Po ^¬ sitionerkennung and control, force control, speed measurement and control, Hysteresekompensati ^¬ on, ZuStandsüberwachung, noise reduction and wear control can be realized. this will

According to the invention achieved in that the method for

Determining and evaluating functional states of a

sensorless electromagnetic actuator having at least one movable armature providing at least one

Reference characteristic, the detection of a current and a

Voltage in an exciter circuit of the electromagnetic actuator, the calculation of at least one modeled characteristic curve by means of a model, wherein the model forms the at least one modeled characteristic curve by an adaptation with at least one hysteresis modeling function of the measured current and the measured voltage and the reference characteristic, and the evaluation and determining the functional states by comparing the measured signals with the at least one model based on the characteristic curve comprises. This provides a process which is insensitive to environmental and operational conditions for the model-based determination of the functional states of an electromagnetic actuator which reliably permits permanent status and wear monitoring, permits miniaturization of the electromagnetic actuator and, due to force regulation and / or speed measurement and regulation allows a low-wear application of the electromagnetic actuator.

The dependent claims show preferred developments of

Invention.

Preferably, a reference characteristic is provided. The reference characteristic describes the chained one electromagnetic flux as a function of the current in the excitation circuit and the position of the armature.

In one embodiment of the invention, it is provided that the reference characteristic is stored as a tabular function in the model. This results in the advantage that in the normal operating state of the electromagnetic actuator no additional adjustment must be performed. According to a further advantageous embodiment of the

The present invention provides that the modeled characteristic curves by means of the model as a function of the current and voltage measured in the excitation circuit and a

Temperature to be calculated. The temperature has one

significant influence on the operating behavior of the

electromagnetic actuator, since especially the winding ^¬ resistance and possibly. the friction ^™ acting on the anchor and counterforce are strongly dependent on it. Moreover, it is advantageous if the model a spring ^¬ modeling and / or a Reibmodellierung and / or a zmodell In ^¬ pulserhaltungssat and / or comprises a hydrodynamic model, whereby the behavior of the electromagnetic actuator is modeled. The complete simulation of the electromagnetic actuator in the model allows, for example, a position detection and control, as well as a force control, a speed measurement and control, through which the armature can be operated particularly low wear, and the generation of noise, for example, the sudden

Closing or opening a valve can be reduced.

Furthermore, it has proven to be advantageous that a hysteresis modeling is implemented. The hysteresis model allows the connection with physical parameters of the magnetic material of the electromagnetic actuator and allows calculation of hysteresis loops for

Magnetic flux and force courses as a function of

Excitation current and from the anchor position. In a particular embodiment of the invention is pre ^¬ see that the model for a Nullpunktversat into account at least one characteristic. The zero offset z of the reference characteristic or the modeled characteristic of the

interlinked magnetic flux in response to the current and the position is to the bias and the Restmag ^¬ netkraft by remanence Br of the magnetic material into account ^¬ term. They depend only on the VorbeStrömung and remain from the second switching or. Bestrungszyklus almost constant. According to a further advantageous embodiment of the invention, the constricting vorlie ^¬ certain functional states comprise a position and / or force of the armature, and / or a speed of the armature and / or detection of

Error conditions and / or a wear control.

Furthermore, it is particularly advantageous when the functional states stands with the aid of the model during operation of the electromagnetic actuator, ^¬ rule at the same time or are calculated at different times. In the case of a simultaneous determination and evaluation of the functional states, it is also possible, in the manner of a control-related observer, to verify functional states which can not be measured during normal operation of the electromagnetic actuator. Thus, a detection of the functional states in actuators whose anchor is not directly accessible due to the operational and / or environmental conditions, only by the control-technical observer possible. According to a further advantageous embodiment of the present invention, the reference characteristic

genus specific (averaged for all actuators of the same type) and / or lot specific (averaged over a

Production charge). This generic or batch specific reference characteristic allows one

Adaptation to the specific and individual characteristics of the electromagnetic actuator used, which makes the model the individual electromagnetic or mechanical

Characteristics of the electromagnetic actuator, in particular a material or processing quality, is fair. At a certain level of dispersion is an individual

Reference characteristic curve for each individual actuator under defined conditions (temperature, mounting position, counterforce).

Furthermore, the present invention relates to a device for operating at least one such sensorless

electromagnetic actuator with an armature comprising at least one control and evaluation unit which is connected by means of an exciter circuit with the electromagnetic actuator, wherein in the control and evaluation unit a model is deposited, wherein the control and evaluation unit a current I and a voltage U of the exciter circuit of the

detected electromagnetic actuator, the model

at least one reference characteristic is provided and wherein the control and evaluation unit by means of the model a modeled characteristic during operation of the electromagnetic actuator for determining the or the functional states

calculated. The functional states are based on a

Comparison determined between the at least one modeled and a metrologically determined characteristic. In addition, it is particularly advantageous when a

Temperature sensor is provided, and that by the Temperature sensor is the temperature of the electromagnetic actuator detected, reducing the influence of temperature on the

Operating behavior of the electromagnetic actuator can be compensated. In operation, the actuator temperature can

Are resistance measurement of the excitation winding ^™ based on the current and voltage values detected periodically (Reu = U / I, this case voltage and current during the resistance measurement must preferably remain constant). Since the winding resistance due to production greater fluctuations can be subject to an adjustment of the starting temperature of the actuator with the Fühlertem ^¬ temperature in the thermally stable state is necessary.

Hereinafter, a preferred embodiment of

Invention with reference to the accompanying drawings

Detail described. In the drawing is:

Figure 1 is a schematic representation of the invention

Device with a Steuer ^™ and evaluation unit, by an excitation circuit with a

electromagnetic actuator is connected,

Figure 2 is a simplified block diagram of a first

Embodiment according to FIG. 1,

Figure 3 is a simplified block diagram of a second

Embodiment of Figure 1 with an additional temperature sensor, and Figure 4 is a simplified representation of a reference characteristic of the concatenated magnetic flux as a function of a measured current in the excitation circuit and the position of the armature of the electromagnetic actuator, and a modeled by a mathematical model modeled characteristic. Preferred embodiment of the invention

Hereinafter, a device 1 according to two preferred embodiments of the invention will be described in detail with reference to Figures 1 to 3.

The device 1 comprises a control and evaluation unit 5, an electromagnetic actuator 3 and an electrical excitation circuit 8, through which the electromagnetic actuator 3 is electrically connected to the control and evaluation unit 5. The electromagnetic actuator 3 has at least one coil L for generating a magnetic field. According to the specific embodiment, the electromagnetic actuator 3 also has a movable armature 4, whose one position δ is variable depending on the generated magnetic field. The electromag ^¬ netic actuator 3, for example, in a solenoid valve for actuating the valve element for regulating a gas or liquid supply or the like, is used.

The control and evaluation unit 5 and the electromagnetic ^¬ cal actuator 3 are spaced - so spatially separated

arranged to each other, whereby by the control and

Evaluation unit 5 of the electromagnetic actuator 3 by means of electrical AnSteuergrößen, namely a current I and a voltage U, is driven. The excitation circuit 8 is formed from at least one electrical line 7, which transmits the electrical AnSteuergrößen and through which the armature 4 in a movement or. Extension to a position δ

is transferred. A corresponding movement or extension is symbolized by the arrow.

As shown in Figure 2, detects the control and

Evaluation unit 5 the current i (t) and the voltage u (t) time resolved, wherein the temporal resolution is chosen sufficiently high to the adjustment of the armature 4 of the

sufficiently dissolve electromagnetic actuator 3.

For model - based determination and evaluation of

Function states of the electromagnetic actuator 3, a current i (t) and a voltage u (t) in the excitation circuit 8 of the magnetic field as a function of time t measured. In a known electrical resistance R is from the

measured quantities for the current i (t) and the voltage u (t) by means of the equation

άΨ

u (t) = i (t) x R + - the concatenated magnetic flux Ψ (i, δ) determines which of the current I and the position δ of the armature 4 is dependent.

To determine the concatenated magnetic flux Ψ in

Dependence on the current I and the position δ is the voltage u (t) and the current i (t) in the excitation circuit 8 of

Magnetic field detected by a suitable measuring device in the control and evaluation unit 5.

The acquired measurement data or measurement series u (t) and i (t) are then integrated according to the above-mentioned equation by means of a suitable numerical method in order to calculate the concatenated magnetic flux Ψ.

Analogous to the detection and calculation of the chained magnetic ^¬ flow of the electromagnetic actuator 3 of the continuous operation, a reference characteristic Kl is in one

Calibration determines which the chained magnetic flux Ψ in a known or. standardized environment as a function of the current I in the excitation circuit and the position of the armature 4 describes. Such a reference characteristic Kl can be seen in FIG.

During calibration, one or more functional generic and / or batch-specific electromagnetic

Actuators 3 selected and measured to a batch and / or genus typical magnetic reference characteristic Kl zu

determine .

In addition, other Modellpa ^¬ parameters such as eddy currents, heat, friction and reaction forces for a mathematical model 11 are determined during calibration. The mathematical model 11 is created with a simulation system such as MATLAB-Simulink and stored in the control and evaluation unit 5 of the respective device 1. The reference characteristic Kl is stored as a tabular function on a storage medium 10 in the control and evaluation unit 5 and serves in addition to the measured current i (t) and the voltage u (t) as input to the mathematical model 11, based on which the modeled characteristics

Kl 'is calculated.

The mathematical model 11 comprises at least one hysteresis ^¬ modeling Ml. Furthermore, the mathematical model 11 may include an eddy current modeling M2, a Reibmodellierung M3, a spring model M4, a pulse conservation model M5 and / or a hydrodynamic model M6 to play recreate the best possible way the electromagnetic actuator 3 of a Magnetven ^¬ TILs in ^¬. Modular-the mathematical ^¬ specific model 11 can be adapted to the area of application of the electromagnetic actuator 3, so that the mathematical model 11 different modules and expansion stages depending on the type of desired and regulated size and the functional state to be detected possesses. A network with its own constant and changeable

Parameter describes in model 11 the individual

Modeling M, to map the behavior of the operation of the electromagnetic actuator 3 realistic and to capture the operating size on the basis of the modeled characteristic Kl ^Λ . The modeled characteristics Kl ^λ corresponds to an approximation of the reference characteristic curve Kl obtained during the calibration to the real ambient conditions.

During operation of the electromagnetic actuator 3, the functional states in the control and evaluation unit 5 are calculated at the same time. The functional states comprise δ the position, speed and acceleration of the armature 4. In the terminology of control technology is the control ^™ and Auswer ^¬ processing unit 5 thus an "observer". Can In addition to the functional states fault conditions by comparing the measured quantities can be detected with the predetermined variables specified by the modeled characteristic curve K ¹

Position as well as jamming in one position.

In particular, the simultaneous or. in real time

Calculation of the functional states allows a position, force and speed control of the armature 4 and thus the determination of the dynamic characteristics of the armature 4 at each time of movement. Such a controlled and CONTROL ^¬ profiled armature 4 can be braked, for example, prior to reaching an end position, in order to reduce an abrupt deceleration in case of impact with a stop. Due to the active control of the armature 4 collision noise and the

Wear of the affected components can be reduced. A development of the device 1 according to the invention is shown in Figure 3, wherein the same or functionally identical parts with the same reference characters as in the first

From management game are designated.

The device 1 according to figure 3 further comprises a temperature ^¬ turfühler 9 by which the temperature is detected T of the electromagnetic actuator. 3 Due to the temperature sensor 9 and the continuous detection of the temperature i9 (t), the temperature influence in the mathematical model 11 can be taken into account. For example, the viscosity of the medium surrounding the armature 4 is highly temperature-dependent. For this purpose, the temperature does not necessarily have to be detected directly at the electromagnetic actuator 3. The size of the electromagnetic actuator 3 is thus kept small.

As inputs of the mathematical model 11, the current i (t), the voltage u (t), the temperature $ (t) and the reference characteristic Kl are provided according to this exemplary embodiment.

The figure 4 is shown in a simplified reference characteristic curve Kl, as well as the calculated by means of the mathematical model 11 first modeled characteristic Kl ^Λ. The batches ^™ and or gattungsspez ifische reference magnetic characteristic Kl of the concatenated magnetic flux Ψ in dependence on the current I and the position δ of the actuator 4 is shown in Figure 4 as a solid line, during which the calculated by means of the mathematical model 11 modeled characteristic Kl ^Λ dashed is shown and the mathematical model 11 takes into account a Nullversversat z of the first characteristic. The course of the magnetic reference characteristic Kl and the modeled characteristic curve Kl ^Λ corresponds to the course of the electromagnetic actuator, wherein the armature 4 of a first

Position 51 is moved to a second position 52.

The reference characteristic Kl resp. the modeled characteristic Kl ^λ of the concatenated magnetic flux can be divided into four From ^¬ sections AI, A2, A3 and A4, one wherein the first portion Al of the first anchor position 51 corresponds to, the Ab ^¬ section A2 a tightening operation of the armature 4 between the first Position 51 and the second position 52, the third portion of the second position 52 and the fourth portion A4 a Ab ^¬ falling operation of the armature 4, in which the armature 4 changes back from the second position 52 to the first position 51.

The second section A2 and the fourth section A4 represent, for example, in a solenoid valve operated with an electromagnetic actuator 3, the opening and closing of the valve. In section AI, the valve is closed, and in the

Section A3 opened, the waste process is typically caused by a return spring.

By comparing the measured quantities with the

Modeled characteristic curve Kl ^Λ on the one hand, the position of the armature 4 can be uniquely determined, on the other hand, for example, error conditions can be determined uniquely.

Thus, a method for model-based determination and evaluation of function can according to the invention states of a sensor ^¬ loose electromagnetic actuator 3 and an apparatus 1 with such a sensor-less electromagnetic actuator are provided 3 which is a position detection and control, a force control of the armature, a VELOCITY capability measurement and control of the armature 4, as well as egg ^¬ ne hysteresis compensation, a condition monitoring, a

Noise reduction and wear control. List of Reference Numerals 1 Device

3 electromagnetic actuator

4 anchors

5 control and evaluation unit

7 line

8 exciter circuit

9 temperature sensors

10 memory

11 mathematical model Ψ chained magnetic flux

I electricity

U voltage

T temperature

i (t) current (as a function of time) u (t) voltage (as a function of time) d (t) temperature (as a function of time] δ position

Claims

claims

Method for the model-based determination and evaluation of functional states of a sensorless

electromagnetic actuator (3) with at least one movable armature (4) comprising:

Providing at least one reference characteristic (Kl),

Detecting a current i (t) and a voltage u (t) of an exciter circuit (8) of the electromagnetic actuator (3),

- Calculation of at least one modeled

Characteristic (Kl ^Λ ) by means of a model (11) and the at least one reference characteristic (Kl), wherein the model (11) the at least one modeled characteristic (KP) by an adjustment with at least one

Hysteresis modeling (Ml) as a function of the measured current i (t) and the measured voltage u (t) and the at least one reference characteristic (Kl) forms, and

Evaluation and determination of the functional states by comparing the characteristic curve determined from the measurement signals (i (t), u (t)) with at least one modeled characteristic curve (Kl ^Λ ).

A method according to claim 1, characterized in that a reference characteristic (Kl) is provided, and that the reference characteristic (Kl) describes the interlinked magnetic flux (Ψ) in dependence on the current (I) and the position (δ) of the armature (4) , 3. The method according to claim 2, characterized in that the reference characteristic (Kl) as tabular /

analytical function is described in the model (11). Method according to one of the preceding claims, characterized in that the model (11) by measuring current i (t), voltage u (t) and / or a temperature θ (t) is adjusted.

Method according to one of the preceding claims, characterized in that the model (11) incorporating a vortex flow modeling (M2) and / or

Friction modeling (M3) and / or a spring modeling (M4) and / or a momentum conservation model (M5) and / or a hydrodynamic model (M6) is formed.

Method according to one of the preceding claims, characterized in that the model (11) has a

Zero point offset of the at least one modeled

Characteristic (Kl ^Λ ,) includes.

Method according to one of the preceding claims, characterized in that the functional states include a position (δ), and / or a force, and / or a speed and / or a fault condition of the armature (4) b z w. include.

Method according to one of the preceding claims, characterized in that the functional states during operation of the actuator (4) offset at the same time or in time

are calculated.

Method according to one of the preceding claims, characterized in that the at least one

Reference characteristic (Kl) is genre-specific and / or batch-specific and / or copy-specific. Device (1) for operating at least one sensorless electromagnetic actuator (3) with an armature (4) according to a method according to one of claims 1 to 9

full :

- At least one Steuer ^™ and evaluation unit (5), which is connected by means of an exciter circuit (8) with the at least one electromagnetic actuator (3), wherein the control and evaluation unit (5) has a

Current i (t) and a voltage u (t) of an exciter circuit (8) of the electromagnetic actuator (3) detected,

- Wherein a reference characteristic (Kl) on a

Storage medium (10) for the control and

Evaluation unit (5) is provided.

11. The device according to claim 10, characterized

a temperature sensor (9) is provided, and that the temperature ( ^■ &) of the electromagnetic actuator (3) is detected by the temperature sensor (9).