DE102011001610A1 - Method for actuating magnetic coil device, involves determining characterizing voltage ratio between current paths for magnetic coil current and between current paths for reference current based on sample values of measured voltage drops - Google Patents

Abstract

The method involves measuring voltage drops (Eri) along current paths for reference current (Ir). Voltage drops (Esj) are measured along current paths for magnetic coil current (Is). Mean values of the respective measured voltage drops are calculated. Sample values of the respective mean values are selected within respective time slots. A characterizing voltage ratio (E) between the paths for the coil current and between the paths for the reference current is determined based on each sample value or a mean value of the selected sample values. An independent claim is also included for a device for controlling a magnetic coil device.

Description

The proposed invention relates to the technical field of electrical engineering, in particular to special features of semiconductor circuits for the control of solenoids (magnetic coils). Shown is a tricky method to control the movements of the moving parts (armature) and to track their current position within the magnetic coils. In this invention, current mirroring and sampling of voltage drops at different times on parallel connected transistors are used to conduct the solenoid current. These transistors are used for coil current control by pulse width modulation (PWM). The invention allows improved accuracy and speed for electromechanically controlled systems. It makes it possible to detect misbehavior such as by blocking the armature (the moving part of the solenoid) within the solenoid coil.

Magnetic coil drivers are used in many applications, such as dispensing fluids, valves and magnetic switches. To control such solenoid coils, the use of PWM signals is more advantageous over that of DC. The PWM signal in this invention can be easily generated by a central processing unit (CPU). The current control is facilitated. The PWM duty cycle determines the value of the current through the solenoid coil and thus causes the movement of the armature within the coil. The maximum current through the solenoid is required at the beginning of the relative movement of the armature relative to the same, in particular during the transition to the active position. Due to the movement of the armature, the inductance of the solenoid changes, also due to the new relative position of the armature relative to the coil.

STATE OF THE ART

Various proposals for solenoid control can be found in the literature: Patent US 7,740,225 "Self Adjusting Solenoid Driver and Method" proposes a method of automatically adjusting the driver output, compensating for the supply voltage drift. The driver circuit generates an output signal for the solenoid having a time dependent component which is a function of the supply voltage. For example, this component may be the peak current duration. As a result, the driver automatically adapts to the supply voltage and can also be used with different supplies. Furthermore, this patent mentions a method in which the driver circuit provides an output signal as a function of the supply voltage.

US 7,161,787 Low Power Solenoid Driver Circuit, a low power solenoid driver, uses a control signal whose dependency provides the solenoid with two different energy levels, a higher "set level" and a lower "hold level". The generation of these two levels is ensured by the control signal, so that the "set level" always applies when the coil current is activated. Unwanted temporal fluctuations of the signal are thereby minimized.

US 6,175,484 "Energy Recovery Circuit Configuration for Solenoid Injector Driver Circuits" describes that the induced energy in the coil is reused in the passive behavior by coupling several solenoids together. These are switches for higher voltages.

US 4,729,056 describes a "Solenoid Driver Control Circuit with Initial Boost Voltage", that is, a solenoid drive circuit with short response times and minimized power dissipation and with low stress on the circuit.

US 5,703,748 "Solenoid Driver Circuit and Method" allows a reduction in the speed of the moving armature. patent US 6,061,224 shows a "PWM Solenoid Driver" so a driver with pulse width modulation. This saves energy by reducing the signal pulse width during the transition phase between two end positions of the armature of the coil.

Compensation of drift, reduction of signal fluctuations and energy loss, as well as speed improvement are thus the different viewpoints in the known publications of the invention. These are more or less different additional requirements placed on the circuits.

In US 4,604,675 a "Fuel Injection Solenoid Driver Circuit" uses a solenoid driver for injection pumps, a storage capacitor for energy, and details to reduce thermal losses. Different ways to reduce the magnetic coil current have been described in the patent literature. If the coil armature has reached the target position, the coil current is reduced, for. In US 5,347,419 "A Current Limiting Solenoid Drive", in US 6,469,885 "A Power Saving Circuit for Solenoid Driver" and in US 4,890,188 "A Solenoid Driver System".

It is important to have a precise knowledge of the position of the armature within the solenoid coil. Thereby Energy can be saved through power reduction. The position of the armature can be determined via the induction change. A known method for inductance determination is based on the control with a reference current over a specific period of time and a subsequent phase for determining the fall time of the current value. The differences in the recorded current consumption times serve to inform about the anchor position, since there is a dependence on the inductance. Is in US 5,053,911 Solenoid Closure Detection disclosed.

U.S. Patent 5,784,245 "Solenoid Driver and Method for Determining Solenoid" describes the use of two reference current pulses, one in the "off" state. the other in the "on" state of two reference current pulses of the solenoid coil. The duration of the current decay phases and the ratio of these time periods are calculated. Based on this ratio, the anchor position can be determined via calibration tables or calculation.

Fiction BACKGROUND

The aim of such inventions is to provide a method of accurately determining the current through a solenoid and detecting the exact position of the armature within it. For the coil current detection, for example, the voltage drop across a known ohmic resistance could be measured, then amplified and finally further processed.

In the invention disclosed herein, a more accurate method for determining the solenoid current is proposed. It combines the known methods of current mirroring and the detection of voltage drops on the one hand small transistors which are connected to a reference current source, and on the other hand to larger power transistors which are connected via the magnetic coil to the supply voltage. The measured voltage drops between the source (or collector) and drain (or emitter) terminals of the transistors are sampled at specific time slots. This results in a unique signature of the solenoid and this signature correlates to a particular armature position relative to the solenoid.

Furthermore, an error detection is possible. The signature of the solenoid reflects the shape of the current curve over time. This shape is roughly detected via the voltage drops across the driver transistors for the solenoids during the current "ON" phase of the PWM signal, which PWM signal is applied to the gate (or base) terminals and turns on the defined current. The signature depends on the one hand on the properties of the magnetic coil (the coil inductance, the coil resistance), and on the other hand on the anchor position, which changes these sizes.

Accurate measurement and analysis of this signature using preferably a microprocessor is the core object of the invention. The approximate detection of the current curves via sample and hold technique (sample and hold method). In this case, a value table of several samples is formed over time, which compares with stored values z. B. allows a calibration cycle.

If the measurement of a voltage drop using a known resistance used to determine the coil current, would result in addition to the power loss caused thereby undesirable heat generation. In addition, the integration of accurate resistances is not easy and requires trimming in production. Consequently, such a solution is unsuitable, especially in higher power applications.

OBJECT OF THE INVENTION

Based on the prior art, a new method has been sought to drive a magnetic coil with a movable armature, with higher speed and positioning accuracy with the lowest possible energy consumption to improve performance should contribute. Possible errors should be detected early to avoid possible damage or consequential damage in good time. The value of the current density should be kept as constant as possible, but also be adaptable to a large current amplitude range. The current position of the armature or moving part through the solenoid coil should be determined as accurately as possible. A simple control principle was sought, which allows both the PWM control with micro-process control but also allows closed-loop control. Changes in the supply, for example due to the battery condition or due to different applied supply voltages within a range, changes due to changing ambient temperatures should also be taken into account, as well as production-related fluctuations of the system characteristics. The influence of all these parameters should be minimized.

THE INVENTION

The above objects of the invention have been achieved according to the claims set forth. For this purpose, the developed method for driving magnet coil devices shows the following elements:
Current from a reference current source is passed through at least one current path addressed by a number N ₁ components. The components serve for the simultaneous pulse width modulation of the current and are electrically connected in parallel. Each component of the subpaths selected by the driver is opened synchronously for a first selectable period of time and closed synchronously for a second selectable period of time. Unnecessary paths are closed the entire time. Simultaneously with the pulse width modulation of the reference current, the pulse width modulation of the magnetic coil current is carried by conduction of this current by an equal or similar number of addressable by further N ₂ components parallel current paths. Again, the addressed paths are opened synchronously at the same time for the first selectable period of time and closed synchronously for the second selectable period of time and unnecessary paths are closed the entire time.

Along all the parallel current paths for the reference current on the one hand and for the coil current on the other hand, the voltage drops across the components serving for the modulation are measured and averages are formed.

The average value for the reference current voltage drop is sampled and buffered within at least one selected time slot of the entire pulse period. The average value for the coil current is also sampled and buffered within at least two selected time slots. All samples are taken cyclically, but at least in two periods of the pulse width signal.

The sample values for the coil current-related voltage drop average value at the modulating components serve as a characterizing vector for the electrical properties of the coil, as a function of the position and velocity of the magnet coil core. The values of this signature thus obtained, given by the sample vector, are used by a control device for pulse width control or for the detection of magnetic coil malfunction. Sample values for the coil current determining voltage drop are averaged and the ratio to that of the reference current path determined. Thus, reference current and coil current can be determined and more precisely controlled.

A special feature of the method is given by the fact that current mirroring for multiplying the reference current of the setting of a defined coil current is used. For this purpose, each addressed path for the reference current is assigned a multiply wider path for the coil current. These mutually associated path pairs each have the same ratio of the path widths to each other at a given common length.

It may be advantageous to assign more than one coil current path to each reference current path.

To form the samples, a known sample-and-hold technique is preferably used, wherein the voltage values of the PWM modulated paths are latched as averaged signals in at least one capacitive element by means of switching elements. In this case, control signals serve, for example, from a microcontroller to select the time slots within the PWM signal period.

For the method, it is favorable that at least two voltage patterns from two time windows are detected in succession and then evaluated in parallel.

An analog-to-digital conversion is advantageously used in order to be able to store the detected voltage patterns, which are present in analogy in the storage capacitors, in digital registers and to further process them as a result of digital processing.

Microprocessor processing is used to acquire the signature (a state-characterizing representation) by storing in registers related to each other, and to allow analysis of the acquired samples, for example, by software. In particular, the voltage relationship between the voltages on the modulating elements of the paths for the coil current and the voltage drop across the reference current path is also determined using stored weighted reference values determined either by calibration or calculation or from simulation results, preferably by digital calculation.

Via a microprocessor, the pulse width over the modulating elements is advantageously determined by control signals at their inputs. These modulating elements turn on the current paths for a certain period of time and the rest of the time. As a result, the average current value is varied by the magnetic coil, so regulated the current increase and the current drop.

A selection of the involved paths is expediently selected via control signals. This selection thus serves to determine the total current density within the paths.

Beyond the method described above, the apparatus for carrying out the method is described.

• 1) eine Referenzstromquelle für den Referenzstrom,
• 2) mindestens zwei parallele Transistor-Kanäle für den Referenzstrom mit Steuer-Gate- oder Basisanschlüssen zur Deaktivierung oder Ansteuerung durch Pulsbreitenmodulation, wobei die Transistorkanäle unterschiedliches Breite zu Längeverhältnis aufweisen,
• 3) zumindest ebenso viele Transistorkanäle zur Kontrolle des Magnetspulenstroms, wobei jeder Transistorkanal einem der parallelen Transistorkanäle für den Referenzstrom zugeordnet ist. Es können auch mehrere Magnetstrom-Transistorkanäle einem Referenzstrom-Transistorkanal zugeordnet sein. Die Zuordnung erfolgt dadurch, dass die Gate- oder Basisanschlüsse mit demselben PWM Ansteuer(oder Deaktivierungs-)signal verbunden sind. Das Breite zu Längeverhältnis der Magnetstromtransistorenkanäle ist ein konstantes Vielfaches des Breite zu Längenverhältnisses der Referenztransistorkanäle,
• 4) Spannungsabgreifstrukturen an jedem Transistor für den Referenzstromanteil und an jedem Transistor für die Spulenstromanteile,
• 5) Vorrichtungen zur Mittelung der Spannungswerte an den Transistoren für den Referenzstromanteil und der Spannungswerte an den Transistoren für die Spulenstromanteile,
• 6) Sample- und Hold-Strukturen vorzugsweise mit Operationsverstärker, Speicherkondensatoren (C₁, C₂, ..., C_k, C_D) und Analogschaltern zur Erfassung der Signatur, welche eine Anzahl zeitliche Abfolge von Abtastwerten während einer PWM-Periode darstellt,
• 7) einen Zeitgeber und Auswahlblock. Dieser steuert die Gate- bzw. Basisanschlüsse der Transistoren jedes Strompfades für den Referenzstrom oder den Magnetspulenstrom derart, dass der zugehörige Transistorkanal hochohmic gesperrt ist oder über Pulsbreitensignale (PWM) geöffnet und geschlossen wird. Die Auswahl entscheidet die Höhe der Stromdichte erlaubt dadurch den gewünschten Mittelwert des Magnetspulenstromes mehr oder weniger rasch zu erreichen, und um die Zeitschlitze für die Erfassung der Samples mithilfe der Analogschalter über Steuerleitungen (c_t1, c_t2, ... c_tk, c_tr) zu bestimmen,
• 8) einen Evaluierungsblock. Dieser erlaubt es, aus den erfassten Spannungswerte-Vektoren (A_t1, A_t2, ..., A_tk) – als Signatur für die aktuelle Position des Magnetspulen-Ankers bei einer gegebenen Geschwindigkeit – gegenüber gespeicherten Referenz-Signaturen,
• 9) einen Rechenblock (53) für das Verhältnis (E) zwischen Abtastwerten (A_t1, A_t2, ..., A_tk) der Spannungsabfälle (e_sj) bei zumindest einigen Transistoren für die Spulenstrompfade, wobei die Spannungsabfälle durch eine Vorrichtung (51) gemittelt werden, einerseits und mit zumindest einem Abtastwert (D) des Spannungsabfalls der Referenzstrompfade andererseits,
• und 10) einen Mikroprozessor.

This therefore has the following components:

• 1) a reference current source for the reference current,
• 2) at least two parallel transistor channels for the reference current with control gate or base terminals for deactivation or control by pulse width modulation, wherein the transistor channels have different width to length ratio,
• 3) at least as many transistor channels for controlling the solenoid current, each transistor channel being associated with one of the parallel transistor channels for the reference current. It is also possible to assign a plurality of magnetic current transistor channels to a reference current transistor channel. The assignment is made by connecting the gate or base terminals to the same PWM drive (or disable) signal. The width to length ratio of the magnetic current transistor channels is a constant multiple of the width to length ratio of the reference transistor channels,
• 4) voltage tap patterns on each transistor for the reference current component and on each transistor for the coil current components,
• 5) means for averaging the voltage values at the transistors for the reference current component and the voltage values at the transistors for the coil current components,
• 6) sample and hold structures, preferably with operational amplifiers, storage capacitors (C ₁ , C ₂ ,..., C _k , C _D ) and analog signature detection switches, which represent a number of time series of samples during a PWM period .
• 7) a timer and selection block. This controls the gate or base terminals of the transistors of each current path for the reference current or the magnetic coil current such that the associated transistor channel is hochohmic locked or opened and closed via pulse width signals (PWM). The choice decides the amount of current density allowed to reach the desired mean value of the solenoid current more or less quickly, and the time slots for the detection of the samples using the analog switches via control lines (c _t1 , c _t2 , ... c _tk , c _tr ) to determine
• 8) an evaluation block. This allows, from the detected voltage value vectors (A _t1 , A _t2 , ..., A _tk ) - as a signature for the current position of the solenoid coil at a given speed - against stored reference signatures,
• 9) a computational block ( 53 ) for the ratio (E) between samples (A _t1 , A _t2 , ..., A _tk ) of the voltage _drops (e _sj ) in at least some transistors for the coil current paths, the voltage drops being caused by a device ( 51 ) are averaged, on the one hand, and with at least one sample (D) of the voltage drop of the reference current paths on the other hand,
• and 10) a microprocessor.

The invention is explained in more detail by the following examples:

1 Namely, the two main functional blocks show the power module 11 and the scanning module 12 , These are normally connected to a digital block for evaluation and control tasks.

2 shows a possible realization of the power module 11 out 1 with n-type transistors to control the two different currents with PWM signals.

3 shows a possible structure of the scanning module 12 out 1 consisting of the blocks for averaging 31 . 32 , the scanning unit 33 and the block 34 for the further processing of the samples.

4 shows a possible realization of the scanning unit 33 from 3 with operational amplifier OPAMP in voltage follower circuit with input capacitor and output capacitors as well as the required switches.

5 is a block diagram of the possible structure for the block 34 for the further processing of the samples 3 with three blocks: one block 51 for averaging two sampled voltage drops representative of the coil current; a second block 52 to perform the signature check to generate either a valid signature or an error signal and a third block 53 for determining the ratio between the averaged, solenoid current-based voltage drop samples and the sample from the reference current path.

6 shows a typical timing diagram of the control signals 3 . 4 . 5 . 6 at the inputs of the sampling switches, at the control terminal of the transistors 1 and the timing diagram at the output of the averaged voltage drop 2a due to the coil current and the voltage drop 2 B due to the mirrored current to the switched-off reference current path.

The proposed invention is essentially through the blocks 11 and 12 as in 1 shown solved. A pulse width modulation signal PWM controls the two currents I _r and I _s in the power module 11 , A current is the reference current I _r which originates from a defined current source. The other current is the solenoid current I _s . This path connects the positive supply voltage across the coil and the modulating elements to the negative power ground. The outputs of the power module 11 are the voltage signals e _ri , e _sj which represent an image of the current _therealong along the modulating elements.

Some of these voltage signals belong to the reference current I _r and form the voltage drops e _ri along the modulating elements, such as switches for the reference current. The remaining voltage signals belong to the solenoid current I _s and form the voltage _drops e _sj along the modulating elements, for. B. switch for the coil current.

In 2 is a possible circuit of the power module 11 shown, the n-type N ₁ transistors T _r1 , T _r2 , ..., T _rN1 , for example, NMOS transistors used to connect the reference _current source to the reference ground terminal; and it uses N ₂ transistors T _s1 , T _s2 , ..., T _{sN2 of the} same type to connect the solenoid _current to the ground (power ground). The N ₁ (or N ₂ ) transistors are connected in parallel with each other at their drain and source terminals. The associated control gates are connected to the signals c _r1 , c _r2 ,... C _ri ,... C _rN1 for the reference _{current side} and to the signals c _s1 , c _s2 ,... C _si , _{sN2 is connected} for the power current side of the coil supply. It is important that each reference transistor T _r1 , T _r2 ,..., T _{rN1 has} a corresponding power transistor T _s1 , T _s2 ,..., T _sN2 for the coil current, which has a multiple Q in its dimensioning M _si = i · Q = Mri · Q, where M _ri = i and i = 1, 2, 3, ...

M usually represents a certain ratio of width to length of the transistor channel, and the smallest transistor has the value M = 1. This makes it possible for the same signal at the terminal s _ri and the connection s _pi the current of one path to the the other path is mirrored, where the amplitude of the mirrored current is proportional to the ratio of the transistor dimensions M _si / M _ri = Q.

The source terminals of a portion of the transistors T _r1 , T _r2 , ..., T _rN1 are connected to reference ground GND _r and the associated drain terminals are connected to the reference _current source I _r . At each modulating transistor T _r1 , T _r2 ,..., T _rN1 , a voltage drop e _ri between drain and source is detected by means of small switches sw _{r1 +} , sw _r1- , sw _{r2 +} , sw _{r2 +} , sw _r2- , ... sw _{rN1 +} , sw _N1- . Tapped.

Likewise, the voltage _drops e _sj at the transistors T _s1 , T _s2 , ..., T _{sN2 become} over the switches sw _{s1 +} , sw _s1- , sw _{s2 +} , sw _{s2 +} , sw _s2- , ..., sw _{sN2 +} , sw _sN2 tapped. These transistors conduct the coil current I _s . The transistors connect the coil to ground GND _p . The modulating signals c _r1 , c _r2 , ... c _ri , ... c _rN1 and c _s1 , c _s2 , ... c _si , ... c _sN2 determine which transistors are used and with the pulse width modulation signal on whose control input is acted upon.

These output signals e _ri , e _{sj of} the power _module 11 are used as input signals to the scanning module 12 guided. In this scanning module 12 Further steps of the invented method are performed. These are in 3 shown. First, the voltage drops e _ri , e _{sj of} the power _module in the blocks 31 . 32 averaged. In the block 31 the signal S is formed, which maps the time-dependent voltage signal between the drain and source terminals of the coil driving transistors and in the block 32 R is the time-dependent voltage signal between the drain and source terminals of the transistors for modulation of the reference current is formed. In the scanning unit 33 the two signals S, R are sampled in certain time windows. One possible scenario of these signals is in 6 shown using the pulses 3 . 4 . 5 and 6 , The scanning unit 33 in 3 shows the associated input _terminals c _t1 , c _t2 , ..., c _{tk of} the pulses for sampling the S signal and c _tr for the R signal. Advantageously it is the signals 3 . 4 . 5 while PWM in "ON" status and pulses 6 while PWM is timing in the "OFF" state.

The result is the output signals of the scanning unit 33 , as in 3 shown, the signals A _t1 , A _t2 , ..., A _{tk of} the sampled amplitudes of the input signal S at k different times and the additional signal D representing the sampled reference signal R.

In 6 the sampling times are shown in relation to the PWM signal.

One possible implementation of the sampling unit is in 4 which shows an operational amplifier OPAMP in voltage follower circuit with a gain of 1. A capacitor C _s is at the defined times (during the sampling 3 . 4 . 5 and 6 ) is loaded to the value of the average voltage drops S or R. This value is also stored in the capacitors C ₁ , C ₂ ,..., C _k and C _D by means of the switches s _t1 , s _t2 ,..., S _tk and s _tr and the OPAMP during the same times.

This results in the analog values A _t2 , ..., A _tk and D in the capacitors, which then in the in the further processing unit 34 in 3 be provided for further processes. This unit evaluates the validity of the amplitude vector, for example by comparison with reference values. Then it will be either an error signal F or the signature value valid signal to the control unit 35 which may be a central processing unit CPU.

The signal processing of the CPU includes the control of the pulse width modulation signals for the control inputs cr1, cr2, ... cri, ... crN1 and cs1, cs2, ... csi, ... csN2. A second signal of the processing unit 34 is the ratio E between a value of the voltage drops At1, At2, ..., Atk related to all or some coil current in the form of an average value Am and the signal D (E = Am / D). The modules of the finishing unit 34 out 3 are in 5 shown.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

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Claims (10)

Method for driving magnetic coil devices, characterized in that it comprises the following steps: a. synchronous pulse width modulation (PWM) of an electrical current which is _fed from a reference current source with a specific reference current (I _r ) through at least one current path addressed via components (T _r1 , T _r2 , T _rN1 ) from a number N ₁ selectable parallel current paths, k ₁ addressed current paths for a first selectable period of time (T ₁ ) are opened synchronously and closed synchronously for a second selectable period of time (T ₂ ), and from the N ₁ current paths N ₁ - k ₁ unaddressed current paths for the two periods (T ₁ + T ₂ ) are closed; b. Synchronous pulse width modulation of a magnetic coil current (I _s ) by channeling the same through at least one of a number of N ₂ over components (T _s1 , T _s2 , ..., T _sN2 ) addressable parallel current paths, k ₂ addressed paths simultaneously for first selectable period of time (T ₁₎ are synchronously opened and closed synchronously (T ₂₎ for the second selectable period of time, and from the N ₂ flow paths unaddressed N ₂ - k ₂ flow paths during two time periods (T ₁ + T ₂₎ are closed ; c. Measuring all voltage drops (e _ri ) along the N ₁ current paths for the reference current (I _r ) and thus along the modulating components (T _r1 , T _r2 , ..., T _rN1 ) and forming a first average value (R) thereof, and Measuring all the voltage _drops (e _sj ) along the N ₂ current paths for the magnetic coil and thus along the modulating components (T _s1 , T _s2 , ..., T _sN2 ) for the solenoid _current and forming a second average value (S) thereof, detecting a first sample value (D) of the first average value (R) within at least one selected time slot □ t _i ( 6 ) and detecting at least two samples (A _t1 , A _t2 , ..., A _tk ) of the second average value (S) within at least two selected time slots □ t _j ( 3 . 4 . 5 ) - all samples repeated within at least two periods with T ₁ + T ₂ = T of the pulse width modulation signal (PWM); d. Use of the samples (A _t1 , A _t2 , ..., A _tk ) as a characterizing vector for the electrical properties of the coil as a function of position and speed of the magnet coil core and use of this signature (A _t1 , A _t2 , ..., A _tk ) for pulse width control or to detect malfunction (F / V) of the magnetic coil; e. Using an average value of at least two of the measured voltage drop samples of the coil current paths (e _sj , A _t1 , A _t2 , ..., A _tk ) and either using a selected voltage drop sample (e _ri , D) or using an average value of two selected voltage drop samples (e _ri , D) of the reference current paths to determine a characterizing voltage ratio (E) between the paths for the coil current (I _s ) on the one hand and the paths for the reference current (I _r ) on the other. A method according to claim 1, characterized in that the current mirroring method for multiplying the reference current (I _R ) is used to obtain a defined coil current (I _S ), wherein each addressed path k _1i of N ₁ paths for the reference _current by a multiple wider Path k _2i of N ₂ paths is assigned to the coil current, so that these associated path pairs have the same ratio (Q) of the path widths for a given common length (L). Method according to claim 1 or 2, characterized in that more than one coil current path is assigned for each reference current path. Method according to one of claims 1 to 3, characterized in that a sample-and-hold technique is used to voltage values (e _ri , e _sj ) of the pulse width modulated paths as averaged signals (R, S) in at least one capacitive element (C _s , C ₁ , C ₂ , ..., C _k , C _D ) via switching elements (s _t1 , s _t2 , ..., s _tk and s _tr ) to be _buffered and their control signals (C _t1 , c _t2 , ..., c _tk , and c _tr ) for selected time slots. A method according to claim 4, characterized in that at least two voltage patterns from two time windows in succession detected, then evaluated in parallel. Method according to one of Claims 4 or 5, characterized in that analog-digital conversion is used in order to be able to store the detected voltage patterns in digital registers and process them further as a result of digital processing. Method according to one of claims 1 to 6, characterized in that microprocessor processing is used for signature formation and analysis of the acquired samples (A _t1 , A _t2 , ..., A _tk ) and by forming the voltage ratio between the voltages at the modulating elements (T _s1 , T _s2 , ..., T _sN2 ) of the paths for the coil current and the voltage drop across the reference current path also using stored weighted reference values determined either by calibration or calculation or from simulation results. A method according to claim 7, characterized in that microprocessor signal generation for pulse width control at the inputs (c _r1 , c _r2 , ... c _ri , ... c _rN1 ; c _s1 , c _s2 , ... c _si , .. c _sN2 ) of the modulating elements (T _s1 , T _s2 , ..., T _sN2 , T _r1 , T _r2 , ..., T _rN1 ) Switching the current paths by controlling the ratio of T ₁ to T ₁ + T _{2 is} used to determine the rise phase and fall phase of the current level. A method according to claim 8, characterized in that a selection of the involved paths via control signals (c _r1 , c _r2 , ... c _ri , ... c _rN1 , c _s1 , c _s2 , ... c _si , ... c _sN2 ) is selected, and thus serves to determine the total current _density within the paths. Device for controlling magnetic coil devices, characterized in that it comprises the following components: a. a reference current source for the reference current (I _r ), b. at least two parallel transistor channels (T _r1 , T _r2 ,..., T _rN1 ) for the reference _current (I _r ) with control gate connections (c _r1 , c _r2 ,... c _ri ,... c _rN1 ) for disabling or driving with pulse width modulation, and wherein the transistor channels have different width to length ratio, c. at least two parallel transistor _channels (T _s1 , T _s2 , ..., T _sN2 ) for controlling the solenoid _current (I _s ), each transistor _{channel or channels} being respectively associated with one of the parallel transistor channels for the reference _current , by their gate - or base terminals (c _s1 , c _s2 , ... c _si , ... c _sN2 ) are connected to the same PWM drive (or deactivation) signal, and whose width to length ratio (M _si ) is a constant multiple (Q) is the width to length ratio (M _ri ) of the reference transistor channels, i. Voltage _{tapping structures} (sw _{r1 +} , sw _r1- , sw _{r2 +} , sw _{r2 +} , sw _r2- , ..., sw _{rN1 +} , SW _N1- ) on each transistor (T _r1 , T _r2 , ..., T _rN1 ) for the reference _{current component} and at each transistor (T _s1 , T _s2 , ..., T _sN2 ) for the coil current _components , e. Devices ( 31 . 32 ) for the averaging of the voltage _values at the transistors (T _r1 , T _r2 ,..., T _rN1 ) for the reference current component and the voltage _values at the transistors (T _s1 , T _s2 ,..., T _sN2 ) for the coil current _components , f , Sample and hold structures ( 33 ) preferably with operational amplifier (OPAMP), storage capacitors (C ₁ , C ₂ , ..., C _k , C _D ) and analog switches for detecting the signature, which represents a number of time series of samples during a PWM period, g. a timer and selection block ( 35 ) to the gate terminals (c _s1 , c _s2 , ... c _si , ... c _sN2 , c _r1 , c _r2 , ... c _ri , ... c _rN1 )) of the transistors To drive signals to either high-impedance lock the path or to form pulse width signals (PWM) to set different current densities, thereby regulating the mean value of the coil current (I _S ) and the time slots for sampling the samples using the analog switches via control lines (c _t1 , c _t2 , ... c _tk , c _tr ) h. an evaluation block ( 52 ) for comparing the detected voltage value vector (A _t1 , A _t2 , ..., A _tk ) - as a signature for the current position of the solenoid coil at a given speed - to stored reference signatures, i. a computational block ( 53 ) for the ratio (E) between samples (A _t1 , A _t2 , ..., A _tk ) of the voltage _drops (e _sj ) in at least some transistors for the coil current paths, the voltage drops being caused by a device ( 51 ) are averaged, on the one hand, and with at least one sample (D) of the voltage drop of the reference current paths on the other hand, j. and a microprocessor.

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