CN101174154A - Control method for angle and position of direct current electric motor - Google Patents

Abstract

An angular position control method for a DC motor rotor shaft. The DC motor includes a plurality of coils with impedance different from that of the other set of coils. The method includes the following steps of: measuring the output current of the motor, identifying the converted pulse according to the variable component of motor current, identifying the reference pulse in the conversion pulse, the value of which is higher than the other pulse, controlling the angular position of rotor shaft through account conversion pulse, calibrating the angular position of rotor shaft according to the reference pulse. And the method is capable of ascertaining the rotor angular position accurately through measuring the output current of motor.

Description

The control method of angle and position of direct current electric motor

Technical field

The present invention relates to a kind of direct current motor with rotor angular position control device; And the control method of the rotor angular position of this motor.

The present invention can be used for driving the motor of mobile vehicular apparatus, such as automobile door glass elevator, and the motor of trapdoor, or seat driving motor.

Background technology

This direct current motor self is well-known.Fig. 1 shows direct current motor.Direct current motor 1 generally includes the framework 2 of stator and is installed on the interior rotor 3 of stator.This rotor 3 comprises and gear 5 engaged worm 4, this gear be connected such as the reel that drives cable.According to the motor of not shown another kind of type, gear can driving with tooth bar or sector gear but not the pinion wheel that drum is cooperated mutually.Motor also comprises the coil that connects mutually with armature spindle 9; Each coil 6 is connected with a pair of thin slice of rectifier 7.Some brushes 8 (generally being two) are used for setting up continuous the contacting of described a pair of thin slice with rectifier 7 at the rotary course that armature spindle 9 is driven.These brushes 8 connect the power supply (not shown) by electric current and are used for giving by electric current coil 6 power supplies of rotor.Therefore, give every pair of coil 6 power supplies continuously, so that make the coil former 2 interior rotors 3 of stator respond to rotation by electric current.The electronic technology (not shown) of controlling also can be associated with motor.For this reason, default usually Printed Circuit Card and comprise being electrically connected and microcontroller of (wherein having) and rectifier brush.

Therefore, as shown in Figure 2, direct current motor can be illustrated by circuit.Be scattered in two circuit branch with coil that rotor connects mutually and each coil has given impedance (resistance and inductance).Therefore, when rotor rotated, alternating current flow through each coil.Therefore, the electric current of motor output has continuous component, in the application of automobile door glass elevator motor, is about 7 amperes usually, and has the variable componenent that is consistent with conversion to the brush on the rectifier thin slice of coil power supply.According to the quantity and the power of electric motor of motor winding, the variable componenent of motor output current is about 0.1A to 1A.

In addition, in motor, the information that often needs control and the rotation of acquisition armature spindle is such as motor revolution, rotational speed, sense of rotation and angle position.In order to ensure its function (such as glass automatic lifting, anti-pinch or other), for the electronic technology of the Motor Control of automobile door glass elevator, these information are particularly necessary.

For the information (such as spinner velocity or sense of rotation) of the rotation aspect of determining motor rotor shaft, use one or more Hall effect sensors known.Magnet ring is arranged on the armature spindle and the rotary magnetic field of the rotation associated of propagation and armature spindle.One or more Hall effect sensors are used to measure the intensity in magnetic field.The Hall effect sensor can be arranged on and approach magnet ring, if or it have guide the magnetic field of ring the direct traffic element of sensor into just can be away from magnet ring.According to the different magnetic field grade that ring is propagated, by measuring the electromagnetic field variable that rotates, each sensor provides to be developed and is used to confirm the rotational speed of armature spindle and the electronic signal of motor sense of rotation and angle position.For example, file EP-A-1146318 has described the automobile door glass elevator motor that comprises the Hall effect sensor that is used to measure spinner velocity and sense of rotation.

The Hall effect sensor provides gratifying result in the control of rotor angular position, still, the use cost of these parts is higher.In addition, the location of Hall effect sensor must be extremely accurate, and this makes that the assembly technology of motor is complicated.

Therefore need a kind of control system that can avoid using the rotor angular position of Hall effect sensor.

For this reason, can be by the variation that detects the motor output current be counted in the conversion of the brush on the thin slice of rectifier and the revolution of motor rotor.

But when motor moved, the control of rotor angular position not only should accurately also should be absolute, that is, stop and motor when restarting at motor, and rotor angular position can not be lost.So far, it is impossible only obtaining such degree of accuracy based on the measurement of motor output current.In fact, when motor stopped and restarting, the electric current that is caused by the conversion of the brush on the rectifier thin slice changed the electric current that is activated or stops and calling and covered.

Motor output current (the I that Fig. 3 shows motor stable state in the prior art when stopping then _Moteur), motor current variable componenent (I _Variable) and the rectifier thin slice on the curve map of the pulse (commutation pulse) that causes of the conversion of brush.Each motor winding has same as volume, therefore has same resistance value.Therefore power supply changes (I to the representational electric current of the conversion of the brush of coil _Variable) obviously identical on intensity.Fig. 7 is the motor curve map that Fig. 3 amplifies when stopping.

Can be observed, under stable state (a-quadrant of Fig. 3 and Fig. 7), the fluctuation of motor current is regular and with respect to continuous component clearly.Therefore each fluctuation of electric current can be detected and be identified as commutation pulse.These pulses are counted by the control electronic technology that can infer the armature spindle angle position.But when assigning the ceasing and desisting order of motor, the motor output current descends suddenly, but rotor so does not suddenly stop the rotation.In the area B of Fig. 3 and Fig. 7, covered by reverse (during the motor short circuit) of electric current with the fluctuations in discharge that the brush conversion is consistent; Therefore lose the angle position of rotor.The zone C of Fig. 3 and Fig. 7 has shown the reverse of motor; The variation of electric current once more with can be consistent by the conversion that electronic unit detected, but (in area B) lost in advance in the angle position of rotor, the counting of these pulses provides the angle position of fict displacement.The region D of Fig. 3 and Fig. 7 shows stopping fully of motor; Continuous and the variable componenent vanishing and not representative for the rotation of rotor of motor by the detected pulse of electronic unit.

Can reach a conclusion from Fig. 3 and Fig. 7, the motor of assigning cease and desist order cause the number of pulses of being counted by the Motor Control electronic unit and and the real angle position of rotor between displacement.Motor full lock state stops also to cause such displacement, and strong rising of the electric current of full lock state covered last commutation pulse.

Fig. 4 shows in the prior art, motor start-up then under stable state, motor output current (I _Moteur), motor current (I _Variable) variable componenent and the curve map of the pulse (commutation pulse) of the conversion of the brush on the rectifier thin slice.

When the motor start-up rotor began to rotate, powerful electric current called (area E) and has covered the electric current that the pulsion phase with brush on the rectifier thin slice meets and change.Therefore, even when motor is got back under the stable state (regional A '), again can not control the angle position of armature spindle based on the counting of the control electronic technology of the commutation pulse of motor current fluctuation, because (area E) angle position has been lost when motor is restarted.The rotor angular position of being inferred by the electronic unit in the regional A ' has displacement with respect to its physical location.After motor a plurality of stopped and restarting, automatic function is lost and endangered to rotor angular position fully, such as the utilization of anti-pinch.

Summary of the invention

The present invention overcomes the obstacle in the prior art, and provide a kind of control device of motor rotor angle position of the measurement based on the motor output current, so that remove the Hall effect sensor, but the present invention, the number of times no matter motor stops and restarting can keep the accurately also measurement of absolute position of rotor angle.

For this reason, the invention provides a kind of direct current motor that has a pair of rotor winding at least, this rotor winding has the resistance value different with other right coils, that is, different from the volume number.This different a pair of coil makes it to sense the electric current obviously bigger than other coils to be changed, and the mark that is used for electronic unit is so that the calibration rotor angular position.Therefore, by the easy measurement of motor output current, can accurately determine the angle position of rotor.

More specifically, the present invention relates to a kind of angle position control method of dc motor rotor axle, this direct current motor comprises many to coil, and at least one pair of coil is different with other right coil impedances, and this method may further comprise the steps:

-measurement motor output current;

-based on the electric electromechanics flow measurement, the identification commutation pulse;

-being identified in the basic pulse in the commutation pulse, these basic pulses are associated with the conversion of given a pair of coil;

-by being counted, commutation pulse controls the armature spindle angle position;

-based on the angle position of this basic pulse calibration armature spindle.

According to feature, this method comprises that also the filtration step of motor current is so that identification commutation pulse and basic pulse.

According to feature, the calibration steps of armature spindle angle position is that the quantity of the commutation pulse that adjustment counts out makes by the quantity of the commutation pulse that count down to from a basic pulse to another basic pulse, is the multiple of motor winding logarithm.

According to embodiment, this method also comprises the steps:

The angle position of the armature spindle that-memory is calibrated on last basic pulse that is identified;

-commutation pulse after last basic pulse that is identified is counted;

-memory is between in the end basic pulse that is identified and motor output current make zero

The commutation pulse quantity that counts out.

According to embodiment, this method also comprises the steps:

-just begin to count commutation pulse up to identifying first basic pulse in case measure the non-zero current of motor output;

-by being adjusted at the angle position that the number of pulses that count down between last basic pulse that is identified and first basic pulse that is identified is calibrated armature spindle, count as follows:

${\left(N_{\mathrm{pulse}}\right)}_{\mathrm{cal}}=\mathrm{Ncoil}\×E(\frac{\mathrm{Nstop}+\mathrm{Nstart}}{\mathrm{Ncoil}}+\mathrm{0,5});$

Wherein:

N _Coil, the motor winding logarithm;

N _Stop, the commutation pulse quantity that between last basic pulse of motor and motor stop, being count down to;

N _Start, from motor start-up up to commutation pulse quantity that first basic pulse count down to;

E, the mathematical operator of " asking whole ".

The invention still further relates to a kind of motorized system of vehicle sash, comprise direct current motor, this Dyn. comprises: many to coil, at least one pair of coil has the resistance value different to coil with other; And the electronic unit that control method is moved according to the present invention.

Description of drawings

By reading embodiments of the present invention detailed description afterwards, other features and advantages of the present invention are manifested, and only provide exemplary also reference accompanying drawing as follows:

-Fig. 1 described, the synoptic diagram of direct current motor;

-Fig. 2 described, with the electrical schematic diagram of motor equity;

-Fig. 3 described, showed when the motor stable state stops then in the prior art

Motor output current (I _Moteur), the variable componenent (I of motor current _Variable) and the thin slice of rectifier on the curve map of pulse (commutation pulse) of conversion of brush;

-Fig. 4 described, was motor start-up in the prior art to be shown then during stable state

Motivation output current (I _Moteur), the variable componenent (I of motor current _Variable) and the thin slice of rectifier on the curve map of pulse (commutation pulse) of conversion of brush;

-Fig. 5 is the motor output current (I that illustrates according to the present invention when the motor stable state stops then _Moteur), the variable componenent (I of motor current _Variable) and the thin slice of rectifier on the curve map of pulse (commutation pulse) of conversion of brush;

-Fig. 6 is that according to the present invention motor start-up motor output current (I during stable state then is shown _Moteu), the variable componenent (I of motor current _Varjable) and the thin slice of rectifier on the curve map of pulse (commutation pulse) of conversion of brush;

-Fig. 7 described, the zoomed-in view of the curve map of Fig. 3.

Embodiment

According to the present invention, motor comprise connect mutually with armature spindle and make the many of rotor induction rotation by the electric current sustainable supply to coil.Every pair of coil is connected with a pair of thin slice of rectifier respectively; Driving by armature spindle in the rotary course of rectifier, some brush set up with the thin slice of rectifier continue contact.Each coil has given resistance value (R.L), and one of them is different with the resistance value of other right coils to the resistance value of coil.

Therefore, the same motor of coil around volume is opposite with having in the prior art, and it is different from other coils the volume number to have at least a pair of coil to have in the coil of motor of the present invention.What at least one pair of coil in the motor of the present invention was different during in the conversion of its brush, can cause that different electric currents changes around the volume number.Therefore, opposite with the motor in the prior art, motor in the prior art has the output current of variable componenent, this current fluctuation intensity is stable (Fig. 3 and Fig. 4) obviously, and motor according to the present invention has the output current of variable componenent and has the current peak of regular intervals in current fluctuation (Fig. 5 and Fig. 6).Be designated as electronic unit mark that this current peak of basic pulse is used to control subsequently so that calibration measurement motor rotor shaft angle position, following will being explained in more detail.

According to the present invention, it is different from other the volume number that motor has at least a pair of coil to have, and is favourable but every pair of coil has with other to the different resistance value of coil.In fact, the applicant points out, the distribution of many resistance values to coil can cause the variation of motor output current, and its electric current changes in the pulse of good each conversion of identification (brush from a pair of coil to another to coil) and can be well the current peak of basic pulse to be positioned.In fact, coil influences each other and does not have and this unique resistance value linear dependence to coil of powering in this time t at given time t built-in motor output current.

For example, in the prior art, having 5 pairs every pair has 18 motor of coil around the volume circle that output current is provided, as shown in Fig. 3 and Fig. 4.According to the present invention, the applicant has simulated motor with five pairs of coils that have around the volume number of turn 13,12,23,19 and 12.Fig. 5 and Fig. 6 show this motor output current.Certainly, can consider that the another kind that carries out around volume distributes between coil, and motor can comprise the coil logarithm that is not five.

Motor of the present invention can be connected with being applicable to the control electronic unit that receives the measurement of motor output current.This electronic unit also can comprise and is applicable to that the electric current measured of explanation changes and be applicable to the microcontroller of the accurate angle position of counting armature spindle.According to the present invention, the control method of this motor rotor shaft angle position is by the electronic unit operation that is associated with motor, with reference to describing in detail among Fig. 5 and Fig. 6.

Motor output current I _MoteurMeasured and be delivered to electronic unit.Variable componenent I _VariableCan extract by suitable filter type.This variable componenent has makes electronic unit can discern the current fluctuation of the pulse (commutation pulse) of conversion, is consistent through the rectifier thin slice with brush, as previously discussed at every turn.

Electronic unit is applicable to the basic pulse with regular intervals 10 that is identified in the commutation pulse in addition.When the conversion of the given a pair of coil in motor winding, this basic pulse occurs; Equating of commutation pulse between the number of times that this basic pulse occurs regularly once more and two the continuous basic pulses to determined number.This basic pulse 10 is discerned by electronic unit, because its be associated at motor output current peak value, it is big that the fluctuation of the variable componenent of these peakedness ratio output currents is wanted, and as mentioned above, these current peaks form because of the special distribution around volume between how right motor winding.Certainly, any distributing around volume of other between coil can be by suitable filtration treatment consideration so that discern basic pulse.In fact, a pair of coil has the resistance value different with other coil (different around the volume number of turn) just is enough to produce in the variable componenent at electric current at least one fluctuation different with other.

In Fig. 5 and the embodiment shown in Figure 6, a basic pulse 10 (because the motor of simulating in embodiment comprises five pairs of coils) appears in per five commutation pulses.Electronic unit therefore not only detection reference pulse 10 can also in detection subsequently, be confirmed by four commutation pulses between two continuous basic pulses.Suitable filtration unit can be discerned commutation pulse and basic pulse.For example, commutation pulse is discerned by the filtration of the variable componenent of motor output, and basic pulse is by discerning with the filtration of the output current of continuous component.

At least (regional A) commutation pulse is systematically discerned under the motor steady operational status, and electronic unit can be controlled the angle position of armature spindle by the counting commutation pulse, because the rotation that manifests directly with armature spindle of these conversions interrelates.In addition, according to the present invention, because calibration is based on basic pulse, the angle position control of this armature spindle is accurate.

In fact, as mentioned above, basic pulse appears in the commutation pulse regularly, because this basic pulse is consistent with a pair of thin slice of brush through given rectifier.Therefore, the angle position of calibration armature spindle is to adjust the quantity of the commutation pulse that counts out, so that the multiple of the logarithm of motor winding always of the quantity from a basic pulse to the commutation pulse of another basic pulse.

Especially, described such as Fig. 3 and Fig. 4 under the situation that the counting of commutation pulse is disturbed consumingly when motor stops or starting,, in case recognize basic pulse when starting, the angle position of armature spindle just still can be calibrated.

Motor stops (Fig. 5), and electronic unit is applicable to last basic pulse 11 of identification because more than four commutation pulse after this basic pulse, and do not have new basic pulse to occur.This last basic pulse 11 makes last known accurate angle position of electronic unit memory armature spindle, and this known rearmost position in the end is calibrated on a basic pulse that is identified 11.

Commutation pulse after the basic pulse that last is identified at this is counted by electronic unit, and controversial shift error is possible with reference to Fig. 3.Then, the quantity N of the electronic unit memory commutation pulse that counts out between last basic pulse that is identified and motor stop fully _Stop, promptly the motor output current makes zero.

(Fig. 6) commutation pulse N during motor start-up _StartBy electronic unit counting, from non-vanishing electric current that motor output occurs to recognizing first basic pulse 12.As shown in Figure 4, the commutation pulse quantity N during startup _StartCalling of big electric current during by motor start-up and makeing mistakes.

According to the present invention, yet, stop and starting in the period at motor, electronic unit is by being adjusted at the number of pulses that is counted out between last basic pulse 11 that is identified and first basic pulse 12 that is identified, reach and calibrate the armature spindle angle position again, so that the quantity of the commutation pulse that the counts out multiple of motor winding logarithm always.

For example, electronic unit can be carried out following calculating to be adjusted at the quantity that stops with the commutation pulse that section occurs start-up time:

${\left(N_{\mathrm{pulse}}\right)}_{\mathrm{cal}}=\mathrm{Ncoil}\×E(\frac{\mathrm{Nstop}+\mathrm{Nstart}}{\mathrm{Ncoil}}+\mathrm{0,5});$

Wherein:

N _Coil,, motor winding logarithm, N _Coil〉=2;

N _Stop, in the end after basic pulse 11, the commutation pulse quantity that counts out when motor stops;

N _Start, motor start-up is up to the commutation pulse quantity that counts out of first basic pulse 12; And

E represents the mathematical operator of " asking whole ".

Adjustment (the N of the commutation pulse quantity that between stopping and starting, occurs _Pulse) _CalBe achieved, error is lower than half wheel of rotor.In fact, in the time period of the peak value of the electric current that stops or starting (about 5 to 10ms), motor can not change sense of rotation and get back to original sense of rotation, and the electrical machinery time constant is 25ms approximately.Therefore, detected pulse certainly with before ceasing and desisting order and the rotation of the startup command armature spindle that direction is consistent afterwards be consistent.

Therefore, but method high precision of the present invention ground control armature spindle angle position.Therefore the electronic unit that is associated with motor also can accurately control the revolution of motor by the counting of commutation pulse and basic pulse; The motor rotational speed can be controlled by the frequency of occurrences of commutation pulse and basic pulse.Therefore the automatic function that is associated with motor does not have additional components (such as the Hall effect sensor) can move yet.

Certainly, the present invention is not limited to the exemplary described embodiment with reference to accompanying drawing; Especially, the distribution around volume of the circle between coil logarithm and coil can change.According to the motor output current value and according to the distribution around volume of coil, select the filtering function of electronic unit.In fact, current peak intensity that is associated with basic pulse and the current fluctuation intensity that is associated with commutation pulse have been determined in many distribution to the impedance between the coil.

Claims (6)

1. the angle position control method of a dc motor rotor axle, described direct current motor comprises many to coil (6), at least one pair of coil is different with other right coil impedances, said method comprising the steps of:

Measure the output current (I of described motor _Moteur);

Based on the measurement of motor current, the identification commutation pulse;

Be identified in the basic pulse (10) in the commutation pulse, described basic pulse is associated with the conversion of given a pair of coil;

Control the angle position of armature spindle by the counting commutation pulse;

Based on basic pulse, the angle position of calibration armature spindle.

2. method according to claim 1 also comprises the filtration step of motor current, so that discern commutation pulse and basic pulse.

3. method according to claim 1 and 2, wherein, the calibration steps of described armature spindle angle position is that the quantity of adjusting the feasible commutation pulse that count down to from a basic pulse to another basic pulse of quantity of the commutation pulse that counts out is the multiple of motor winding logarithm.

4. according to a described method in the claim 1 to 3, also comprise the steps:

The armature spindle angle position of calibration is gone up in memory at last basic pulse (11) that is identified;

Last basic pulse (11) commutation pulse afterwards that counting is being identified;

Memory is the commutation pulse quantity (N that counts out between making zero of a basic pulse that is identified (11) and motor output current in the end _Stop).

5. method according to claim 4 also comprises the steps:

Begin to count commutation pulse (N once the non-zero current that measures motor output _Start) up to recognizing first basic pulse (12);

By being adjusted at the angle position that the number of pulses that count down between last basic pulse that is identified (11) and first basic pulse that is identified (12) is calibrated armature spindle, count as follows:

${\left(N_{\mathrm{pulse}}\right)}_{\mathrm{cal}}=\mathrm{Ncoil}\×E(\frac{\mathrm{Nstop}+\mathrm{Nstart}}{\mathrm{Ncoil}}+\mathrm{0,5});$

N _Coil, the motor winding logarithm;

N _Stop, the commutation pulse quantity that between last basic pulse of motor (11) and motor stop, being count down to;

N _Start, the commutation pulse quantity that is count down to up to first basic pulse (12) from motor start-up;

E, the mathematical operator of " asking whole ".

6. the motorized system of a vehicle sash comprises direct current motor, and this Dyn. comprises: many to coil, at least one pair of coil has the resistance value different to coil with other; And according to each described electronic unit that control method is moved in the claim 1 to 5.

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