CN111800039B - Rotor position information confirming method, vector control method and device of synchronous motor - Google Patents

Rotor position information confirming method, vector control method and device of synchronous motor Download PDF

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Publication number
CN111800039B
CN111800039B CN202010569637.8A CN202010569637A CN111800039B CN 111800039 B CN111800039 B CN 111800039B CN 202010569637 A CN202010569637 A CN 202010569637A CN 111800039 B CN111800039 B CN 111800039B
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current
rotor position
synchronous motor
response
rotor
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CN111800039A (en
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祝远宁
徐常升
程海珍
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Gree Green Refrigeration Technology Center Co Ltd of Zhuhai
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Gree Green Refrigeration Technology Center Co Ltd of Zhuhai
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    • 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
    • H02P6/20—Arrangements for starting
    • 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
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/14—Estimation or adaptation of machine parameters, e.g. flux, current or voltage
    • H02P21/16—Estimation of constants, e.g. the rotor time constant
    • 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
    • H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
    • H02P21/34—Arrangements for starting
    • 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
    • H02P25/00—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details
    • H02P25/02—Arrangements or methods for the control of AC motors characterised by the kind of AC motor or by structural details characterised by the kind of motor
    • H02P25/022—Synchronous motors
    • H02P25/024—Synchronous motors controlled by supply frequency
    • H02P25/026—Synchronous motors controlled by supply frequency thereby detecting the rotor position
    • 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
    • H02P27/00—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage
    • H02P27/04—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage
    • H02P27/06—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters
    • H02P27/08—Arrangements or methods for the control of AC motors characterised by the kind of supply voltage using variable-frequency supply voltage, e.g. inverter or converter supply voltage using dc to ac converters or inverters with pulse width modulation
    • 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
    • H02P6/18—Circuit arrangements for detecting position without separate position detecting elements
    • 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
    • H02P2205/00—Indexing scheme relating to controlling arrangements characterised by the control loops
    • H02P2205/01—Current loop, i.e. comparison of the motor current with a current reference

Abstract

The invention provides a rotor position information confirming method, a vector control method and a vector control device of a synchronous motor. Wherein the method comprises the following steps: acquiring sampling current of a synchronous motor, wherein alternating current voltage is injected into a d axis of the synchronous motor; determining a real part of a positive sequence current of a response current in a target coordinate system based on the sampling current, wherein the response current is a current generated in response to the alternating voltage; and determining the current rotor position difference according to the incidence relation between the real part and the rotor position difference. The embodiment of the invention has the effects of accurately and timely tracking the position of the rotor, reducing/avoiding the shaking of the rotating speed, smoothly controlling, reducing the cost and the like.

Description

Rotor position information confirming method, vector control method and device of synchronous motor
Technical Field
The invention relates to the field of synchronous motors, in particular to a method for confirming rotor position information, a method and a device for vector control of a synchronous motor.
Background
The existing starting technology of the permanent magnet synchronous motor without the position sensor mainly comprises the following three types:
firstly, the phase current signals of the motor are acquired simultaneously by generating periodic square wave current signals with frequency changing linearly and taking 360-degree electrical angles as cycles. A. B, C only two phases are conducted in the positive half period and the negative half period of each period, and the conduction angle is 120 degrees. And performing proportional integral operation on the phase current signal and the square wave current signal to obtain an operation result, performing power linear amplification, and finally sending the signal after the power linear amplification to an external permanent magnet synchronous motor to complete motor driving. The control strategy has the defects that the positioning of the motor rotor is not accurate enough, the polarity judgment is wrong, and the starting failure rate is high when the motor parameter changes under some severe working conditions.
The second is a control method of smooth start. The permanent magnet synchronous motor is set to a constant torque operation mode or a constant rotational speed operation mode after being started. The smooth start control method comprises open-loop control and closed-loop control, and q-axis current drive is utilized. The disadvantage of this method is that the way in which the rotor is positioned and how the position of the rotor can be found is not given precisely. And the maximum q-axis given current is calculated according to the maximum value of the motor torque, when the motor parameter changes or the torque (load) changes, the safe q-axis current cannot be given, and the possibility of destructively damaging the motor, which cannot be started or demagnetized, exists.
And thirdly, a starting control method of the permanent magnet synchronous motor without the position sensor based on the assumed rotation coordinate method has the advantages that the situation that the internal temperature is not changed when the motor is just started is considered, the back electromotive force constant of the motor is still a design value at the moment, and the amplitude of the voltage vector is almost in direct proportion to the rotation speed of the motor during no-load starting. The rotation speed estimation correction limiting value in the assumed rotation coordinate method is adjusted by using the point, so that the non-speed smooth starting of the permanent magnet synchronous motor can be realized in the algorithm control adopting the speed and current double closed loop without the switching process of two control algorithms. The control method has the defects that the control method is only suitable for starting in a normal state, when the motor runs for a period of time, the internal temperature is changed, the motor parameters are changed, the control method strongly depends on the starting of the motor parameters, the general adaptability is not high, and the starting success rate cannot be ensured.
At present, experts and researchers in various fields have a spice, such as an observer/estimator-based method, a kalman filter method, a back emf method, a PWM/SVPWM method and a signal injection method, based on the research of sensorless starting of a permanent magnet synchronous motor, but most of the researches are realized based on a permanent magnet synchronous motor mathematical model, have strong dependence on motor parameters, and extract components of rotor position information after coordinate change according to a stator voltage equation and a flux linkage equation to perform tracking control. The algorithms are not strong in adaptability and high in robustness to changes of motor parameters, operating environments or working conditions, and positioning failure and reverse rotation are caused easily due to rotor position positioning errors and rotor position information update failure, so that the conditions of starting failure and damage to a compressor mechanism occur, or the conditions of step loss and stall occur after the starting is successful. Taking a permanent magnet synchronous motor applied to an air conditioner and a refrigerator compressor as an example, an air conditioner user can start and stop operation intentionally or unintentionally in the using process, the refrigerator can also continuously start and stop operation in the switching process of a defrosting period and a refrigerating period, and the user experience is directly influenced by the smoothness and the success rate of starting.
Disclosure of Invention
The present invention is directed to solving the problems associated with the prior art described above. The invention provides a method for confirming rotor position information on one hand and a method and a device for controlling a synchronous motor vector on the other hand. The scheme provided by the invention can accurately and timely track the position of the rotor, reduce/avoid the shaking of the rotating speed, realize smooth control, realize low cost and the like.
According to a first aspect of the present invention, there is provided a method for confirming rotor position information, including:
acquiring sampling current of a synchronous motor, wherein alternating current voltage is injected into a d axis of the synchronous motor;
determining a real part of a positive sequence current of a response current in a target coordinate system based on the sampling current, wherein the response current is a current generated in response to the alternating voltage;
and determining the current rotor position difference according to the incidence relation between the real part and the rotor position difference.
According to a second aspect of the present invention, there is provided a vector control method for a synchronous motor, comprising:
injecting alternating current voltage into a d axis of the synchronous motor;
determining a current rotor position difference using the method of any one of claims 1-6;
determining a current rotor position and a current rotor angular frequency based on the current rotor position difference and a set value;
carrying out vector control on the motor according to the set value, the current rotor position and the current rotor angular frequency;
wherein the set values include a rotor position set value and a rotor angular frequency set value.
According to a third aspect of the present invention, there is provided a rotor position observer including:
the current sampling module is used for acquiring sampling current of the synchronous motor, wherein alternating voltage is injected into a d axis of the synchronous motor;
a current processing module for determining a real part of a positive sequence current of a response current in a target coordinate system based on the sampling current, wherein the response current is a current generated in response to the alternating voltage;
and the position difference determining module is used for determining the current rotor position difference according to the incidence relation between the real part and the rotor position difference.
According to a fourth aspect of the present invention, there is provided a vector control device for a synchronous motor, comprising:
the voltage injection module is used for injecting alternating-current voltage into a d axis of the synchronous motor;
a rotor position observer according to a third aspect of the present invention; and
and the vector control module is used for carrying out vector control on the synchronous motor based on the rotor position information determined by the rotor position observer.
By adopting the related embodiment of the invention, the rotor position information is determined by utilizing the incidence relation between the rotor position difference and the real current part under the specific condition and the characteristic that the rotor position difference is insensitive to the change of the motor parameters, and the invention has the effects of accurately and timely tracking the rotor position, reducing/avoiding the rotating speed jitter, smoothly controlling, lowering the cost and the like.
Drawings
In order to more clearly illustrate the technical solution of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic flow diagram of a method of rotor position information validation according to one embodiment of the present invention;
FIG. 2 is a flow chart diagram of a method of vector control of a synchronous machine according to one embodiment of the present invention;
FIG. 3 is a flow chart diagram of a method of vector control of a synchronous machine according to one embodiment of the present invention;
FIG. 4 is a block diagram of a rotor position observer according to one embodiment of the invention;
FIG. 5 is a block diagram of a synchronous motor vector control apparatus according to an embodiment of the present invention;
FIG. 6 is a diagram illustrating an angle tracking effect according to a prior art;
FIG. 7 is a diagram illustrating the effect of angle (error) tracking according to a prior art;
FIG. 8 is a graph illustrating the tracking effect of rotational speed according to a prior art;
FIG. 9 illustrates a graph of the tracking effect of rotational speed according to an embodiment of the invention;
FIG. 10 illustrates an angle tracking effect diagram according to an embodiment of the invention;
FIG. 11 is a schematic diagram illustrating the effect of angular error tracking according to an embodiment of the present invention;
FIG. 12 illustrates a phase A current waveform at the moment of start-up of a scheme according to an embodiment of the invention;
FIG. 13 illustrates measured A-phase current waveforms at start-up under harsh conditions according to one prior art technique;
fig. 14 is a graph of an implant voltage waveform for the d-axis according to one embodiment of the invention.
Detailed Description
As used herein, the terms "first," "second," and the like may be used to describe elements of exemplary embodiments of the invention. These terms are only used to distinguish one element from another element, and the inherent features or order of the corresponding elements and the like are not limited by the terms. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms, such as those defined in commonly used dictionaries, are to be interpreted as having a meaning that is consistent with their context in the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Those skilled in the art will understand that the devices and methods of the present invention described herein and illustrated in the accompanying drawings are non-limiting exemplary embodiments and that the scope of the present invention is defined solely by the claims. Features illustrated or described in connection with one exemplary embodiment may be combined with features of other embodiments. Such modifications and variations are intended to be included within the scope of the present invention.
Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, a detailed description of related known functions or configurations is omitted to avoid unnecessarily obscuring the technical points of the present invention. In addition, the same reference numerals refer to the same circuits, modules or units throughout the description, and repeated descriptions of the same circuits, modules or units are omitted for brevity.
Further, it should be understood that one or more of the following methods or aspects thereof may be performed by at least one control unit or controller. The term "control unit" or "controller" may refer to a hardware device that includes a memory and a processor. The memory is configured to store program instructions, and the processor is specifically configured to execute the program instructions to perform one or more processes that will be described further below. Moreover, it is to be understood that the following method may be performed by an apparatus comprising a control unit in combination with one or more other components, as will be appreciated by one of ordinary skill in the art.
Fig. 1 is a schematic flow diagram of a rotor position information confirming method according to an embodiment of the present invention, and referring to fig. 1, the method includes:
100: and acquiring the sampling current of the synchronous motor. Wherein an alternating voltage is injected into a d-axis of the synchronous motor. Exemplary, as shown in fig. 14, is a graph of the injection voltage waveform for the d-axis.
In this embodiment, an ac voltage is injected into the d-axis (the response current generated on the q-axis is very small and negligible), and the frequency of the injected voltage can be determined according to the switching frequency of the power switching tube selected by hardware, and needs to be lower than the switching frequency of the inverter to ensure that the injected frequency is lower than the fundamental frequency. Thus, the current response of the injection voltage can be accurately extracted subsequently.
102: and determining the real part of the positive sequence current of the response current in the target coordinate system based on the sampling current. Wherein the response current is a current generated in response to the alternating voltage.
104: and determining the current rotor position difference according to the incidence relation between the real part and the rotor position difference.
The inventor of the invention finds that the real part of the positive sequence current of the response current in the target coordinate system has a correlation with the rotor position difference. Therefore, the present embodiment can determine the rotor position difference by analyzing the response current.
By adopting the rotor position information confirming method provided by the embodiment, the rotor position difference is determined by analyzing the response current generated in response to the d-axis injection voltage. The method is independent of motor parameters, and can overcome or weaken various defects of the method based on the motor parameters.
For example, when the permanent magnet synchronous motor is applied to an air conditioner or a refrigerator, the motor is frequently turned on and off. In the conventional scheme, when the working conditions (including pressure, temperature, load and the like) change greatly and the load changes in the operation process, the rotor position without the position sensor is easy to have larger deviation in positioning, the rotor position angle is not tracked timely or the tracking is wrong, so that the rotating speed is greatly shaken (refer to the figure)6 and 7), overshoot or large jitter at the starting moment is easy to occur, and the rotation speed convergence has periodic regulation (see fig. 8). Wherein, fig. 6 and 7 are schematic diagrams of the angle tracking effect of the prior art, thetarRepresenting the actual rotor position angle, thetasRepresenting the measured rotor position angle. FIG. 8 is a diagram illustrating the effect of the prior art speed tracking, ωrRepresenting actual rotor speed, ωsRepresenting the measured rotor speed.
The scheme provided by the embodiment of the invention has good rotating speed tracking effect, does not have the overshoot condition and is almost close to the ideal rotating speed tracking state (see figure 9). And the rotor position angle is updated timely, and the position angle of the rotor can be quickly positioned for synchronous tracking even under heavy load or severe working conditions (see fig. 10 and 11). Fig. 9 shows a rotation speed tracking effect diagram of the embodiment of the present invention, fig. 10 shows an angle tracking effect diagram of the embodiment of the present invention, and fig. 11 shows an angle error tracking effect diagram of the embodiment of the present invention.
For another example, in the conventional three-stage starting method, after the working condition changes in practical application, repeated positioning (as shown in fig. 13, an actually measured a-phase current waveform when the starting is performed under a severe working condition in the prior art) is likely to occur, or positioning errors occur, which may cause damage to the motor structure. By adopting the embodiment of the scheme, the position of the rotor can be quickly extracted (see fig. 9, 10 and 12), and the problems that the permanent magnet synchronous motor is easy to reverse and damage the structure at the starting moment are solved. Fig. 12 is a waveform diagram of a phase a current at the starting moment of the scheme according to the embodiment of the present invention. As can be seen from fig. 12, the rotor position angle can be corrected at the starting moment by using the embodiment of the invention, and the open loop operation can be smoothly performed.
In addition, the relevant scheme of the embodiment of the invention extracts the position angle information of the rotor based on the current response, has quick response, can quickly converge when reaching the given rotating speed, and has good stability. Overshoot and oscillation are not easy to occur, and smooth control can be realized at the starting moment. Therefore, the problems of strong jitter and large rotating speed error at the moment of starting the permanent magnet synchronous motor are solved. Is beneficial to realizing accurate, smooth and stable starting.
In addition, because the excitation magnetic field of the injected voltage vector signal is aligned with the rotor magnetic field, torque variation cannot occur, and torque pulsation cannot be generated, so that the problem of jitter in the starting process can be solved well, the smooth starting of the air conditioner and the refrigerator compressor is ensured, the success rate is high, the starting performance is good, and a user can have good product experience.
In addition, the scheme provided by the embodiment of the invention can realize novel starting with high success rate only by changing the current sampling calculation mode and FOC (magnetic field orientation control) on the basis of the original hardware. The realization mode is simple, and the maintenance is convenient.
Optionally, in an implementation manner of this embodiment, the process 100 is implemented by: and carrying out clark conversion on the stator three-phase current of the synchronous motor to obtain the stator two-phase current. The stator two-phase current is a current in an α - β coordinate system or a resultant current based on the current in the α - β coordinate system.
Optionally, in an implementation manner of this embodiment, the process 100 is implemented by: and carrying out clark conversion on the stator three-phase current of the synchronous motor to obtain the stator two-phase current. The stator two-phase current is a current in an α - β coordinate system or a resultant current based on the current in the α - β coordinate system. Further, process 100 may also include: the stator two-phase currents are adjusted based on the previous rotor position estimate, which may more quickly bring the rotor position difference closer to 0. Wherein the previous position estimate is determined based on a previous rotor position difference and a rotor position setpoint, the previous rotor position difference being determined based on a previous sampled current.
Optionally, in an implementation manner of this embodiment, the process 102 is implemented by: filtering the sampling current to obtain a positive sequence current of the response current; and converting the positive sequence current of the response current into a rotating coordinate system to obtain the positive sequence current under the rotating coordinate system, and determining the real part of the positive sequence current. Wherein the filtering process passes a signal defining a frequency as an injection frequency (a fundamental frequency, a carrier frequency, an injection frequency, etc. exist in the current), and filters out a negative sequence current, thereby leaving only a positive sequence current containing rotor position difference information. The positive sequence current is converted to a rotating coordinate system (d-q coordinate system) to obtain the magnitude of the real part, which is proportional to the rotor position difference.
Specifically, the correlation between the real part and the rotor position difference satisfies: y is k · x, where y represents the real part, x represents the rotor position difference, and k is a constant related to a parameter of the alternating voltage. The inventors have discovered and utilized this correlation to determine/track rotor position differences in a manner that is independent of motor parameters and achieves at least one of the aforementioned benefits. For a detailed description of the association, refer to the following.
Optionally, in an implementation manner of this embodiment, after determining the current rotor position difference, the method further includes: and judging whether the current rotor position difference is 0, if not, adjusting the stator three-phase current of the synchronous motor in the direction of enabling the current rotor position difference to be 0. Furthermore, the sampling current can be continuously acquired and the process can be repeated for 100-104 times based on the newly acquired sampling current until the rotor position difference is 0.
Those skilled in the art will appreciate that validation of rotor position information is a process of cyclic adjustment validation. In this implementation, in the k-th loop adjustment, when it is determined that the current rotor position difference is not 0, the obtained k-th rotor position estimation value may be fed back to the subsequent sampling current. Because the k-th rotor position estimation value contains the current rotor position information in the adjusting process, the value of the position angle of the sampling current can be quickly adjusted in the subsequent circulation adjustment, so that the adjusting times can be reduced, and the correction of the rotor position angle error can be quickly responded. The principle is that the value of the k time can be known to be larger or smaller through the estimated value of the k time rotor position. And then, the position angle of the sampling current can be compared and corrected, so that in the (k + 1) th circulation adjustment, the corrected sampling current is processed by modules such as a band-pass filter and the like, the position angle is processed, and the (k + 1) th rotor position difference is obtained. This way the rotor position difference is favoured to be 0 quickly.
Fig. 2 is a flow chart illustrating a vector control method of a synchronous machine according to an embodiment of the present invention, and referring to fig. 2, the method includes:
200: an alternating voltage is injected into the d-axis of the synchronous machine. The frequency of the injection voltage can be determined according to the switching frequency of the power switching tube selected by hardware, and needs to be lower than the switching frequency of the inverter to ensure that the injection frequency is lower than the fundamental frequency. Thus, the current response of the injection voltage can be accurately extracted subsequently.
202: a current rotor position difference is determined. Specifically, please refer to the embodiment and implementation manner shown in fig. 1, which are not described herein again.
204: based on the current rotor position difference and a set point, a current rotor position and a current rotor angular frequency (equivalent to a current rotor angular velocity) are determined. Wherein the set values include a rotor position set value and a rotor angular frequency set value.
206: and carrying out vector control on the motor according to the set value, the current rotor position and the current rotor angular frequency.
With the present embodiment, vector control can be performed on the synchronous motor, and the technical effects described in the embodiment shown in fig. 1 are achieved.
Alternatively, in this embodiment, the process 204 may employ existing vector control logic, which will be described in detail in the embodiment shown in fig. 3. Fig. 3 is a flowchart illustrating a vector control method of a synchronous machine according to an embodiment of the present invention, and referring to fig. 3, the method includes:
300: a voltage vector is injected. The frequency signal of the injected voltage acts on the d-axis, while the response current generated on the q-axis is small and negligible. The switching frequency of the power switching tube selected by hardware is determined to be lower than the switching frequency of the inverter so as to ensure that the injection frequency is lower than the fundamental frequency, thereby ensuring that the current response of the injection frequency is accurately extracted.
301: the sampling current is obtained. For example, the lower arm current of the power switch tube is sampled by means of single resistance sampling. Specifically, as shown in the figure, three-phase currents ia, ib, and ic output by the three-phase inverter bridge are first obtained (for example, ic is determined according to ia + ib + ic ═ 0). Then, CLARK transformation is carried out on ia, ib and ic to obtain i alpha and i beta under an alpha-beta coordinate system. The resultant current is determined based on i α and i β.
302: and performing exponential transformation on the sampling current. An estimated position angle may be obtained at this time, and as previously described, the estimated position angle of the sampled current may be adjusted based on the previously determined position estimate to increase the speed at which the rotor position difference is 0.
303: the current is (fundamental frequency, carrier frequency, injection frequency, etc. existing in the current) is input to a band-pass filter for filtering, so that a signal with the frequency of the injection signal passes through, and a negative sequence current in the signal is filtered out, and only a positive sequence current is left.
304: and performing angle transformation on the positive sequence current to obtain the positive sequence current in a rotating coordinate system, and determining the partial size of the positive sequence current. The actual part contains information on the rotor position difference (this will be described in detail later).
305: and processing KP proportional gain and KI integral gain by using a PI controller.
306: the output signal of the PI controller is processed by an oscillator to convert the rotor position difference signal into an estimated rotor position angle θ s.
Then, on the one hand, the motor vector is adjusted according to the set sub-position angle θ r and the estimated rotor position angle θ s, which is the prior art and will not be described herein. On the other hand, the rotor position difference information may be fed back to the current sample of 301 to quickly correct the rotor position difference information.
In the embodiment, the PARK transformation, namely the PARK transformation, projects the three-phase a, b and c currents of the stator onto the direct axis (d axis) and the quadrature axis (q axis) rotating along with the rotor and the zero axis (0 axis) perpendicular to the dq plane, so that the diagonalization of the stator inductance matrix is realized, and the operation analysis of the synchronous motor is simplified. I.e. the abc-coordinate system is transformed to the dq-coordinate system. Similarly, inverse PARK transforms the dq coordinate system to the abc coordinate system.
SVPWM is a short term of Space Vector Pulse Width Modulation (Space Vector Pulse Width Modulation), and is a Pulse Width Modulation wave generated by a specific switching mode composed of six power switching elements of a three-phase power inverter, and can make an output current waveform as close to an ideal sinusoidal waveform as possible.
CLARK transformation, namely transforming the three-phase current of a, b and c into a stationary alpha and beta coordinate system.
IPMSM: a permanent magnet synchronous motor.
Optionally, in an implementation manner of this embodiment, the sampled current may be input to the DSP module after being amplified, so as to perform the processing of 302-306.
The correlation between the real part and the rotor position difference mentioned in the embodiments of the present invention can be verified by the following logic:
1) injection angular frequency of omega0Amplitude of V0The estimated voltage vector V of the rotor coordinate system into the motoriCan be expressed as: vi＝V0cos(ω0t)
2) Voltage vector V in stator reference frames(ωsTo estimate the angular frequency of the rotor coordinate system) can be expressed as:
Figure BDA0002549065160000101
3) referencing the stator with a voltage vector V in a coordinate systemsVoltage vector V transformed to rotor reference framer(ωrFor the actual rotor coordinate system angular frequency) can be expressed as:
Figure BDA0002549065160000102
4) the real part and the imaginary part of the voltage on the d axis and the q axis, which are equivalent to the voltage drop of the leakage inductance of the d axis and the q axis on the rotor coordinate system, can be expressed as follows:
Figure BDA0002549065160000103
Ldσ: d-axis inductance leakage inductance, Lqσ: q-axis inductance leakage inductance
5) The injection of the voltage vector signal into the stator of the motor results in a corresponding current response at the rotor, which can be expressed as:
Figure BDA0002549065160000104
Figure BDA0002549065160000105
6) converting the current response in the rotor coordinate system to the stator coordinate system can be expressed as:
Figure BDA0002549065160000111
7) the resultant current vector in the stator coordinate system can be expressed as:
Figure BDA0002549065160000112
wherein L is0＝Ldσ+Lqσ，L1＝Lqσ-Ldσ
8) Extracting positive sequence i from synthesized stator current phasorspAnd a negative sequence current isnIt can be expressed as:
Figure BDA0002549065160000113
Figure BDA0002549065160000114
9) rotor position information exists in positive sequence current of rotating reference coordinate system
Figure BDA0002549065160000115
And (3) performing coordinate transformation on the stator positive sequence current, and expressing as:
Figure BDA0002549065160000116
10) in actual operation, (ω)r-ωS) Is a very small value, the real part of the positive sequence current vector in the rotating coordinate system can be expressed as:
Figure BDA0002549065160000117
wherein Δ θ ═ θr-θs)＝(ωr-ωS)t
The accuracy and the availability of the correlation relationship between the real part and the rotor position difference found by the invention can be verified according to the analysis. Meanwhile, the practical use significance of the embodiment related to the invention can be determined according to the comparison in the foregoing and the provided figures related to the beneficial effects.
Fig. 4 is a block diagram of a rotor position observer according to an embodiment of the invention, and referring to fig. 4, the rotor position observer includes a current sampling module 40, a current processing module 42, and a position difference determining module 44. The details will be described below.
In this embodiment, the current sampling module 40 is configured to obtain a sampled current of the synchronous motor, wherein an ac voltage is injected into a d-axis of the synchronous motor, so that the sampled current carries a response current of the ac voltage and a normal current for controlling the motor. The frequency of the alternating voltage is less than the fundamental frequency.
Specifically, the current sampling module 40 may perform clark conversion on the stator three-phase current of the synchronous motor to obtain the stator two-phase current. Or further, the current sampling module 40 may adjust the stator two-phase current based on a prior rotor position estimate, which may more quickly bring the rotor position difference closer to 0. Wherein the previous position estimate is determined based on a previous rotor position difference and a rotor position setpoint, the previous rotor position difference being determined based on a previous sampled current.
In the present embodiment, the current processing module 42 is configured to determine a real part of a positive sequence current of a response current in a target coordinate system based on the sampled current, wherein the response current is a current generated in response to the alternating voltage.
Optionally, in an implementation manner of this embodiment, as shown in fig. 4, the current processing module 42 may include: the filtering submodule is used for filtering the sampling current to obtain a positive sequence current of the response current; and the conversion submodule is used for converting the positive sequence current of the response current into a rotating coordinate system, obtaining the positive sequence current in the rotating coordinate system and determining the real part of the positive sequence current. Or, further, the current processing module may further include a current adjustment sub-module for adjusting the sampled current based on a previous rotor position estimate.
In this embodiment, the position difference determining module 44 is configured to determine the current rotor position difference according to the correlation between the real part and the rotor position difference. The correlation between the real part and the rotor position difference satisfies y ═ k · x, where y denotes the real part, x denotes the rotor position difference, and k is a constant related to the parameter of the ac voltage (see the verification logic above).
Optionally, in an implementation manner of this embodiment, the rotor position observer is further configured to determine whether a current rotor position difference is 0 after obtaining the current rotor position difference, adjust the stator three-phase current of the synchronous motor in a direction that the current rotor position difference is 0 if the current rotor position difference is not 0, and feed back the current rotor position difference to the sampling current module so as to adjust the subsequent sampling current.
Fig. 5 is a block diagram of a synchronous motor vector control apparatus according to an embodiment of the present invention, and referring to fig. 5, the synchronous motor vector control apparatus includes: and a voltage injection module 50 for injecting an alternating voltage into the d-axis of the synchronous machine. For the specific logic, please refer to the foregoing description. A rotor position observer 52 for confirming rotor position information based on the response current of the voltage injection module 50. For a description of the rotor position observer 52, reference is made to fig. 4. And a vector control module 54 for performing vector control on the synchronous motor based on the rotor position information determined by the rotor position information confirming module. For the control logic of the vector control module 54, refer to the embodiment shown in fig. 3. And are not described in detail herein.
For descriptions of related terms, explanations, specific processing logic, technical effects, and the like in the device embodiments, please refer to the corresponding descriptions in the method embodiments, which are not repeated herein.
The drawings referred to above and the detailed description of the invention, which are exemplary of the invention, serve to explain the invention without limiting the meaning or scope of the invention as described in the claims. Accordingly, modifications may be readily made by those skilled in the art from the foregoing description. Further, those skilled in the art may delete some of the constituent elements described herein without deteriorating the performance, or may add other constituent elements to improve the performance. Further, the order of the steps of the methods described herein may be varied by one skilled in the art depending on the environment of the process or apparatus. Therefore, the scope of the present invention should be determined not by the embodiments described above but by the claims and their equivalents.
While the invention has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims (12)

1. A method for confirming rotor position information of a synchronous motor, comprising: acquiring sampling current of a synchronous motor, wherein alternating current voltage is injected into a d axis of the synchronous motor; determining a real part of a positive sequence current of a response current in a target coordinate system based on the sampling current, wherein the response current is a current generated in response to the alternating voltage; determining the current rotor position difference according to the incidence relation between the real part and the rotor position difference;
the frequency of the alternating voltage is less than the fundamental frequency.
2. The method of claim 1, wherein determining the real part of the positive sequence current of the response current in the target coordinate system based on the sample current comprises: filtering the sampling current to obtain a positive sequence current of the response current; and converting the positive sequence current of the response current into a rotating coordinate system to obtain the positive sequence current under the rotating coordinate system, and determining the real part of the positive sequence current.
3. The method of claim 2, wherein the correlation of the real part to the rotor position difference is: y is k · x, where y represents the real part, x represents the rotor position difference, and k is a constant related to a parameter of the alternating voltage.
4. The method of claim 1, wherein the obtaining a sampled current of a synchronous machine comprises: and carrying out clark conversion on the stator three-phase current of the synchronous motor to obtain the stator two-phase current.
5. The method of claim 4, wherein obtaining the sampled current of the synchronous machine further comprises: the stator two-phase current is adjusted based on a previous rotor position estimate.
6. The method of claim 1, wherein an excitation magnetic field of the voltage vector signal of the d-axis injected alternating voltage is aligned with a rotor magnetic field.
7. The method according to any one of claims 1 to 6, further comprising: and judging whether the current rotor position difference is 0, if not, adjusting the stator three-phase current of the synchronous motor in the direction of enabling the current rotor position difference to be 0.
8. A vector control method of a synchronous machine, the method comprising: injecting alternating current voltage into a d axis of the synchronous motor; determining a current rotor position difference using the method of any one of claims 1-7; determining a current rotor position and a current rotor angular frequency based on the current rotor position difference and a set value; carrying out vector control on the motor according to the set value, the current rotor position and the current rotor angular frequency; wherein the set values include a rotor position set value and a rotor angular frequency set value.
9. A rotor position observer, comprising: the current sampling module is used for acquiring sampling current of the synchronous motor, wherein alternating voltage is injected into a d axis of the synchronous motor, and the frequency of the alternating voltage is smaller than the fundamental frequency; a current processing module for determining a real part of a positive sequence current of a response current in a target coordinate system based on the sampling current, wherein the response current is a current generated in response to the alternating voltage; and the position difference determining module is used for determining the current rotor position difference according to the incidence relation between the real part and the rotor position difference.
10. The rotor position observer according to claim 9, wherein the current processing module comprises: and the conversion sub-module is used for converting the positive sequence current of the response current into a rotating coordinate system, obtaining the positive sequence current in the rotating coordinate system and determining the real part of the positive sequence current.
11. The rotor position observer according to claim 10, wherein the current processing module, while including the filtering submodule and the converting submodule, further includes: and the current adjusting submodule is used for adjusting the sampling current according to the estimated value of the previous rotor position.
12. A vector control apparatus of a synchronous machine, characterized by comprising: the voltage injection module is used for injecting alternating-current voltage into a d axis of the synchronous motor; a rotor position observer according to any one of claims 9-11; and the vector control module is used for carrying out vector control on the synchronous motor based on the rotor position information determined by the rotor position observer.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101358989A (en) * 2008-09-12 2009-02-04 长江三峡能达电气有限责任公司 Method for measuring rotate speed of synchronous generator based on circulation method
CN101714844A (en) * 2009-11-10 2010-05-26 哈尔滨工业大学 Method for detecting initial position of magnetic pole of rotor of built-in permanent magnetic synchronous motor
CN109067283A (en) * 2018-07-27 2018-12-21 江苏大学 A kind of permanent-magnetic synchronous motor rotor initial position identification system and method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2944659B1 (en) * 2009-04-21 2011-04-01 Schneider Toshiba Inverter METHOD FOR DETERMINING THE POSITION OF THE FLOW VECTOR OF AN ENGINE

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101358989A (en) * 2008-09-12 2009-02-04 长江三峡能达电气有限责任公司 Method for measuring rotate speed of synchronous generator based on circulation method
CN101714844A (en) * 2009-11-10 2010-05-26 哈尔滨工业大学 Method for detecting initial position of magnetic pole of rotor of built-in permanent magnetic synchronous motor
CN109067283A (en) * 2018-07-27 2018-12-21 江苏大学 A kind of permanent-magnetic synchronous motor rotor initial position identification system and method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
Initial rotor position detection in PMSM based on low frequency harmonic current injection;Duro Basic et al.;《Proceedings of 14th International Power Electronics and Motion Control Conference EPE-PEMC 2010》;20101021;第2页第2栏第3段-第5页最后1段 *
基于旋转坐标系解调的内置式永磁同步电机旋转高频注入法位置观测;刘善宏 等;《电工技术学报》;20200229;第35卷(第4期);第708-716页 *

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