Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
  • H02P6/00—Arrangements for controlling synchronous motors or other dynamo-electric motors using electronic commutation dependent on the rotor position; Electronic commutators therefor
  • H02P6/14—Electronic commutators
  • H02P6/16—Circuit arrangements for detecting position
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01D—MEASURING NOT SPECIALLY ADAPTED FOR A SPECIFIC VARIABLE; ARRANGEMENTS FOR MEASURING TWO OR MORE VARIABLES NOT COVERED IN A SINGLE OTHER SUBCLASS; TARIFF METERING APPARATUS; MEASURING OR TESTING NOT OTHERWISE PROVIDED FOR
  • G01D5/00—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable
  • G01D5/12—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means
  • G01D5/244—Mechanical means for transferring the output of a sensing member; Means for converting the output of a sensing member to another variable where the form or nature of the sensing member does not constrain the means for converting; Transducers not specially adapted for a specific variable using electric or magnetic means influencing characteristics of pulses or pulse trains; generating pulses or pulse trains
• • G—PHYSICS
  • G05—CONTROLLING; REGULATING
  • G05B—CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS
  • G05B19/00—Programme-control systems
  • G05B19/02—Programme-control systems electric
  • G05B19/18—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form
  • G05B19/19—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path
  • G05B19/27—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path using an absolute digital measuring device
  • G05B19/31—Numerical control [NC], i.e. automatically operating machines, in particular machine tools, e.g. in a manufacturing environment, so as to execute positioning, movement or co-ordinated operations by means of programme data in numerical form characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path using an absolute digital measuring device for continuous-path control

Definitions

• the invention relates to an electronically commutated electric motor.
• the electronically commutated electric motor has a stator and a particular permanent magnetic rotor formed.
• the electric motor also has a control unit, which is operatively connected to the stator and designed,
• the electric motor also has at least one rotor position sensor which is designed to detect a rotor position, in particular an angular position, of the rotor and to generate a rotor position signal representing the rotor position.
• the control unit is designed to generate the control signals in dependence on the rotor position signal.
• an electric motor in which a rotor position of a rotor is determined by means of a sensor and an oscillator synchronized to the output signal of the sensor.
• the rotor position is derived between detection positions of the output signal by means of a vibration of the oscillator.
• the problem with fast-rotating electronically commutated electric motors is that during operation of the electric motor the rotor position detection must be carried out with a high detection frequency if a frequent change of a commutation phase occurs during one rotor revolution. pattern.
• the control unit of the electric motor then has to have a correspondingly high computing capacity.
• the control unit of the electronically commutated electric motor of the aforementioned type is designed to sample and quantize the rotor position signal and to generate a digital prediction rotor position signal.
• the digital prediction rotor position signal forms a temporal data stream which corresponds to the sampled and quantized rotor position signal and comprises at least one or a plurality of future rotor position values that lead beyond the rotor position signal in time.
• the so predicted rotor position for commutation of the electric motor are available before the rotor position sensor, in particular an angle sensor, after conversion of an example analog rotor position signal in a digital rotor position signal, the rotor position signal so converted can provide for further signal processing available.
• the rotor position sensor is preferably an angle sensor.
• the angle sensor is, for example, a giant magneto-resistive sensor (GMR sensor) or an anisotropic magnetoresistive sensor (AMR sensor).
• the electric motor has, for example, a plurality of Hall sensors, which are each designed to generate an analog rotor position signal.
• the angle sensor in particular the GMR sensor or AMR sensor, is designed to generate a time-continuous, analog rotor position signal. An angular resolution of the angle sensor is then determined by a sampling rate of an analog-to-digital converter which converts the analog rotor position signal analog-to-digitally.
• the prediction rotor position signal may be formed, for example, by a predetermined number of rotor position values, wherein the rotor position values are updated with each new rotor position value detected by the angle sensor and, more preferably, additionally converted by an analog-to-digital converter according to the FIFO principle. This can advantageously be done with non-stationary motion patterns, the commutation of the electric motor. For example, during a rotor revolution, the control unit may turn a variety of mutually different Kommut réellesmuster apply to the stator.
• control unit is designed to generate the digital prediction rotor position signal by means of an approximation function as a function of the rotor position signal as the output function to be approximated.
• the approximation function is a polynomial, in particular at least second degree or exactly second or third degree.
• Further advantageous embodiments of an approximation function are a spline function or an exponential function.
• control unit has a timer, and is designed to commutate the stator, in particular by means of the commutation pattern, as a function of a time signal generated by the timer and as a function of the prediction rotor position signal.
• the stator can advantageously be commutated to a time determined according to the approximation function after a time signal generated by the timer, for example a time interval thus formed, has elapsed.
• control unit may be designed to determine the commutation time by means of linear interpolation between two, in particular successive, preferably future, rotor position values of the prediction rotor position signal.
• the invention also relates to a method for operating an electronically commutated electric motor, in particular of the electric motor described above.
• a rotor position is detected by means of a rotor position sensor and a rotor position signal corresponding to the rotor position is generated.
• the rotor position signal is preferably sampled and quantized, and a particularly digital prediction rotor position signal forming a temporal data stream is generated.
• the prediction rotor position signal represents the sampled and quantized rotor position signal and includes at least one or a plurality of future rotor position values that extend beyond the rotor position signal.
• the digital prediction rotor position signal is dependent on further detected by means of the rotor position sensor
• the digital prediction rotor position signal is generated as an output function by forming an approximation function as a function of the rotor position signal.
• the output function is the function to be approximated, which can form support points for generating the approximation function.
• the prediction rotor position signal can also be transmitted via a signal transmitted through the interpolation points.
• the prediction rotor position signal can also be transmitted via a signal transmitted through the interpolation points.
• the approximation function is preferably a polynomial function of the second or third degree.
• a commutation of the stator takes place as a function of the prediction rotor position signal after the passage of a time interval, wherein the
• Expiry corresponds to a predetermined Kommut réelleszeittician.
• the commutation preferably takes place by means of at least one, preferably predetermined, commutation pattern.
• the commutation can advantageously already take place prior to the presence of a rotor position value generated by means of the rotor position sensor.
• the sequence of the time interval is preferably determined by means of linear interpolation between two rotor position values of the prediction rotor position signal.
• the control unit has only adders as arithmetic operators for the linear interpolation. It is also conceivable to determine the future rotor position value as a function of the approximation function. The multiplications necessary for this can advantageously be effected by a correspondingly fast arithmetic unit.
• the control unit is controlled, for example, by a control program which is stored on a data carrier and inserted together with the data carrier
• the invention also relates to a control unit according to the above-described type for an electric motor of the type described above.
• the control unit then has no rotor and no stator and is designed to be connected to a stator of an electric motor.
• Figure 1 shows an embodiment of an electronically commutated electric motor with the control unit according to the invention
• FIG. 2 shows a method for operating the electric motor shown in FIG. 1;
• FIG 3 shows a diagram which illustrates the operation of the electric motor shown in Figure 1 and the method shown in Figure 2.
• FIG. 1 shows-schematically-an exemplary embodiment of an electronically commutated electric motor 1.
• the electric motor 1 has a stator 10 with three stator coils, namely a stator. torspule 12, a stator coil 14 and a stator coil 16 on.
• the stator 10 also has an angle sensor which can generate an example analog rotor position signal.
• the angle sensor 18 is designed to detect a rotor position of a rotor 1 1 of the electric motor 1.
• the angle sensor 18 is connected by means of a connection 50 to a control unit 30 of the electric motor 1.
• the control unit 30 has an analog-to-digital converter 27 which is connected on the input side to the connection 50 and thus to the angle sensor 18.
• An angular resolution of the angle sensor is determined by a sampling rate of the analog-to-digital converter in the case of the analog, in particular time-continuously formed rotor position signal.
• the analog-to-digital converter 27 is connected on the output side via a connecting line 54 to a polynomial generator 29.
• the analog-to-digital converter 27 is designed to sample the rotor position signal received on the input side via the connection 50 and to generate a temporal sequence of sampling values, which respectively represent an amplitude value of the rotor position signal.
• the analog-to-digital converter 27 is connected on the output side via a connecting line 54 to a polynomial generator 29.
• the polynomial generator 29 is designed to generate an approximation function, which at least approximately represents a curve represented locally by the sampled values, as a function of the sampled values received via the connecting line 54 -the rotor position of the rotor 11.
• the polynomial generator is preferably designed to generate the approximation function by means of a method of least square error.
• the approximation function is preferably a polynomial, in particular a polynomial of the second or third degree. It is also conceivable - especially as a function of the required computing time of the polynomial generator - a polynomial more than third degree.
• the polynomial generator 29 is designed to determine polynomial coefficients of the previously determined approximation function, in particular of the polynomial, and to output these on the output side via a connecting line 56 to a coefficient memory 32.
• the polynomial generator 29 has, for example, an FIR filter for each polynomial coefficient, in this exemplary embodiment three exemplary FIR filters 36, 38 and 39.
• the coefficient memory 32 is designed to store the polynomial coefficients generated by the polynomial generator 29.
• the coefficient memory 32 is connected on the output side via a connecting line 58 to a predictor 34.
• the predictor 34 is designed to read out the coefficients stored in the coefficient memory 32 via the connecting line 58, and to generate a temporally successive data stream representing rotor position values and output this via the connecting line 60 to a control unit 42 on the output side.
• the data stream comprises temporally successive future rotor position values-shown in dotted lines in this exemplary embodiment-which each represent a future rotor position not yet detected by the angle sensor 18. That one- tenstrom forms in this embodiment, the aforementioned prediction rotor position signal.
• n sample, integer or number ⁇ 1;
• T a sampling period
• the control unit 42 is connected to a timer 40 and is designed to commutate the stator 10 at least in dependence on the prediction rotor position signal received via the connection line 60.
• the control unit 42 is connected on the output side via a connection 53 to a power output stage 25 of the electric motor 1.
• the control unit 42 is designed to control the power output stage 25 for generating a rotating magnetic field by means of the stator coils 12, 14 and 16.
• the power output stage 25 is the output side via a connection 52 with the stator 10, and there connected to the stator coils 12, 14 and 16.
• the control unit 42 is designed to precisely determine the commutation times for commutating the stator 10 as a function of the particular high-resolution time signal received by the timer 40.
• the polynomial generator 29 can advantageously have a finite impulse response (FIR) filter for each polynomial coefficient of the polynomial coefficients held in the coefficient memory 32.
• FIR finite impulse response
• the control unit 42 is also connected on the input side via the connecting line 54 to the analog-to-digital converter 27 and can receive the digitized rotor position signal from the analog-to-digital converter.
• the control unit 42 is configured to determine the rotor position values calculated by the predictor 34 by means of linear interpolation between two consecutive prediction values for commutation of the stator coils and to correspondingly control the power output stage 35 for commutating the stator coils.
• the polynomial generator 29 and the predictor 34 are jointly formed by a plurality of FIR filters, wherein an FIR filter is formed for each, in particular future, rotor position value. As a result, for example, two FIR filters are available for two future rotor position values.
• the coefficient memory 32 may be omitted in this embodiment.
• FIG. 2 shows an exemplary embodiment of a method for commutating an electronically commutated electric motor.
• a rotor position of a rotor of the electronically commutated electric motor is detected in a step 70, in particular by means of an angle sensor, and a rotor position signal is generated which represents at least one rotor position of the rotor.
• the rotor position signal is transmitted by means of an analogue
• Digital converter digitized and generates a digitized rotor position signal.
• a polynomial is generated which at least approximately approximates the digitized rotor position values.
• polynomial coefficients which represent the previously formed polynomial are buffered.
• a polynomial is formed by means of a predictor as a function of the previously generated polynomial coefficients and a data stream is generated depending on the polynomial, which includes rotor position values in a time range in which the rotor position values detected by the angle sensor lie, and in addition future rotor position values which have not yet been detected by the angle sensor and / or are not yet represented by the signal generated by the analog-to-digital converter 24.
• a commutation pattern is selected, for example from a plurality of commutation patterns held in stock, and in a step 82 the stator is supplied with the commutation pattern.
• FIG. 3 shows a diagram 90.
• the diagram 90 has a time axis 91 and an amplitude axis 92.
• Diagram 90 shows a curve 95 which connects samples 101, 102, 104, 106, 108, 110 and 112 together.
• the curve 95 corresponds to a polynomial which has been generated, for example, by means of the polynomial generator 29 shown in FIG. 1, and which represents a rotor position profile.
• the polynomial 95 is a third degree polynomial in this embodiment.
• the rotor position value 101 has been detected by the angle sensor, for example by the angle sensor 18 shown in FIG.
• the time interval 96 represents a sampling period of an analog-to-digital converter, for example of the analog-to-digital converter 27 illustrated in FIG.
• the rotor position values 100, 102, 104, 106, 108 1, 10 and 1 12 are spaced from the preceding and subsequent rotor position values by the time interval 96, respectively.
• the rotor position value 101 follows the rotor position value 100 after the time interval 98.
• the rotor position value 103 follows the rotor position value 102 after the time interval 98.
• the time interval 98 represents a computing time that the analog-to-digital converter requires to digitize the rotor position signals transmitted by the angle sensor perform.
• the control unit for further signal processing and for controlling the commutation times, the control unit-for example, the control unit 30 in FIG. 1 -is available in digitized form later-delayed in this example by the time interval 98-as it is from the Angle sensor have been detected. Shown are the commutation times 1 15 and 1 17. The commutation 1 15 is spaced from the rotor position value 102 by the time interval 99. The time interval 99 is shorter than the time interval 98, so that the commutation time 15 takes place after the presence of the digital rotor position value 103 - which corresponds to the rotor position of the rotor position value 102.
• a sampling frequency for detecting a rotor position of the rotor may be lower than without prediction using the predictor polynomial.
• the rotor position values 100, 102, 104, and 106 have been detected by the angle sensor, the rotor position value 108, the rotor position value 110, and the rotor position value 112 may have been generated using the predictor polynomial.
• the control unit for example, the control unit 42 in Figure 1, the rotor position values generated by the predictor 108, 1 10 and 1 12 with those detected by the angle sensor rotor position values 109, 1 1 1 and 1 13th compare and use to form another polynomial curve of the predictor polynomial.

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• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Control Of Motors That Do Not Use Commutators (AREA)
• Human Computer Interaction (AREA)
• Manufacturing & Machinery (AREA)
• Automation & Control Theory (AREA)

Priority Applications (4)

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Publications (1)

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Family Applications (1)

Country Status (7)

Cited By (1)

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Citations (4)

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• 2009
  • 2009-08-17 DE DE200910028590 patent/DE102009028590A1/de not_active Withdrawn
• 2010
  • 2010-07-27 KR KR1020127004193A patent/KR20120041766A/ko not_active Application Discontinuation
  • 2010-07-27 CN CN201080036344.8A patent/CN102474210B/zh active Active
  • 2010-07-27 WO PCT/EP2010/060828 patent/WO2011020681A1/de active Application Filing
  • 2010-07-27 JP JP2012525115A patent/JP5479592B2/ja not_active Expired - Fee Related
  • 2010-07-27 EP EP10734756A patent/EP2467929A1/de not_active Withdrawn
• 2012
  • 2012-02-10 IN IN1258DEN2012 patent/IN2012DN01258A/en unknown

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