CN111342726B - Direct torque control method and system for permanent magnet synchronous motor - Google Patents
Direct torque control method and system for permanent magnet synchronous motor Download PDFInfo
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- H—ELECTRICITY
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- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/12—Stator flux based control involving the use of rotor position or rotor speed sensors
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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
- H02P21/00—Arrangements or methods for the control of electric machines by vector control, e.g. by control of field orientation
- H02P21/13—Observer control, e.g. using Luenberger observers or Kalman filters
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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
- 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
- H02P21/141—Flux estimation
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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
- 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
- H02P21/20—Estimation of torque
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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
- 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
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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
- 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
- H02P27/12—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 pulsing by guiding the flux vector, current vector or voltage vector on a circle or a closed curve, e.g. for direct torque control
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- 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
- H02P6/10—Arrangements for controlling torque ripple, e.g. providing reduced torque ripple
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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
- H02P2205/00—Indexing scheme relating to controlling arrangements characterised by the control loops
- H02P2205/05—Torque loop, i.e. comparison of the motor torque with a torque reference
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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
- H02P2205/00—Indexing scheme relating to controlling arrangements characterised by the control loops
- H02P2205/07—Speed loop, i.e. comparison of the motor speed with a speed reference
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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
- H02P2207/00—Indexing scheme relating to controlling arrangements characterised by the type of motor
- H02P2207/05—Synchronous machines, e.g. with permanent magnets or DC excitation
- H02P2207/055—Surface mounted magnet motors
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Abstract
The invention provides a direct torque control method of a surface-mounted permanent magnet synchronous motor with constant switching frequency, which comprises the following steps: acquiring three-phase stator currents of a motor at the current moment k to perform coordinate transformation; measuring the rotor position of the motor at the current moment k to obtain a rotating speed signal, and obtaining an electromagnetic torque given value through a speed controller; calculating to obtain a stator flux linkage vector and an electromagnetic torque of the motor at the current moment k; acquiring the relation between the electromagnetic torque increment of the motor and the reference voltage vector of the current moment k and the relation between the stator flux linkage increment and the reference voltage vector of the current moment k in one control period; calculating to obtain a reference voltage vector required to be output according to the electromagnetic torque error and the stator flux linkage error of the motor; the space vector modulation module outputs a required driving signal so that the switching frequency of the inverter is kept constant. The method ensures the rapidness of motor torque response, and has simple and clear control structure and easy realization.
Description
Technical Field
The invention relates to the field of industrial automation, in particular to a direct torque control method and system for a surface-mounted permanent magnet synchronous motor with constant switching frequency.
Background
Direct torque control is a commonly used control method for surface-mounted permanent magnet synchronous motors. The traditional direct torque control method takes motor torque and stator flux linkage as control objects, and selects corresponding output voltage vectors from a switch table by judging the deviation between the current motor torque and stator flux linkage and corresponding given values and combining the sector where the stator flux linkage is located. The motor torque and stator flux linkage fluctuation is large because the motor can only select from limited effective voltage vectors and the amplitude of the output voltage vector is constant, and meanwhile, the loss and noise of a control system are increased because the switching frequency of an inverter is not constant, and the operation performance of the motor control system is influenced.
By using the space voltage vector modulation technology, a voltage vector with continuously variable amplitude and angle can be output, and constant switching frequency can be further obtained by reasonably controlling the switching-on sequence of the switch. Therefore, the space voltage vector modulation is used for replacing a switching table, and the defects of large fluctuation of torque and stator flux linkage and non-constant switching frequency existing in the traditional direct torque control can be effectively overcome. In the conventional direct torque control of a surface-mounted permanent magnet synchronous motor based on space voltage vector modulation, a PI controller is generally required to obtain an output reference voltage vector, but the PI controller can impair the rapidity of motor torque response, and optimal controller parameters are not easy to determine.
Disclosure of Invention
The present invention is made to solve the above problems, and an object of the present invention is to provide a method and a system for controlling direct torque of a surface-mounted permanent magnet synchronous motor with constant switching frequency.
The invention provides a direct torque control method of a surface-mounted permanent magnet synchronous motor with constant switching frequency, which is characterized by comprising the following steps of: step 1, collecting three-phase stator current i of a motor at current moment k sa (k)、i sb (k)、i sc (k) Obtaining the current i of the current moment k on a two-phase static coordinate system through coordinate transformation sα (k)、i sβ (k) The method comprises the steps of carrying out a first treatment on the surface of the Step 2, measuring the rotor position of the motor at the current moment k, further obtaining a rotating speed signal, and obtaining an electromagnetic torque given value through a speed controller
Step 3, calculating to obtain a stator flux linkage vector psi of the motor at the current moment k according to a stator flux linkage current model of the motor and an electromagnetic torque equation s (k) Electromagnetic torque T e (k) The method comprises the steps of carrying out a first treatment on the surface of the Step 4, obtaining a control period T of the motor according to a dynamic mathematical model of the motor on a two-phase static coordinate system s Medium electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) Is, and stator flux linkage delta phi s Reference voltage vector u for i and current time k s (k) Is a relationship of (2); step 5, calculating to obtain the reference voltage vector which needs to be output according to the electromagnetic torque error and the stator flux linkage error of the motor>
Furthermore, the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency provided by the invention has the following characteristics: the coordinate transformation in the step 1 is Clarke coordinate transformation:
furthermore, the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency provided by the invention has the following characteristics: the stator flux linkage current model in the step 3 is as follows:
ψ s ＝ψ r +L s i s (2)
in the formula (2), ψ s Is stator flux linkage vector, ψ r Is the rotor flux linkage vector, L s I is the stator inductance s For stator current vectors，
On a two-phase stationary coordinate system with a horizontal axis alpha and a vertical axis beta, the stator flux linkage component ψ for the current time k sα (k)、ψ sβ (k) The method meets the following conditions:
in the formula (3), θ r I is the included angle between the flux linkage vector of the rotor and the alpha axis sα (k)、i sβ (k) As a component of the stator current, a stator flux component ψ sα (k)、ψ sβ (k) The stator flux linkage vector psi of the motor at the current moment k can be obtained s (k)。
Furthermore, the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency provided by the invention has the following characteristics: wherein, the electromagnetic torque equation in the step 3 is:
in the formula (4), T e For electromagnetic torque, n p For the pole pair number of the motor, the symbol x represents the vector cross multiplication operation, and the stator flux linkage vector psi of the current moment k is substituted in the formula (4) s (k) Stator current vector i at current time k s (k) The electromagnetic torque T of the motor at the current time k can be obtained e (k)。
Furthermore, the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency provided by the invention has the following characteristics: wherein, in step 4, the motor is controlled in a control period T s Medium electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) The relationship acquisition process of (1) is as follows:
in a two-phase stationary coordinate system, a stator flux linkage vector psi is used s And stator current vector i s As a state variable, the state equation of the motor is expressed as:
in the formulas (5) and (6), R s Is stator resistance L s Is the stator inductance, ω is the rotor electrical angular velocity, ψ r For the rotor flux linkage vector, j is the virtual axis operator, u s As a vector of the voltages,
discretizing the state equation of the motor to represent one control period of the motor control system as T s The stator flux linkage and stator current discrete equation at time k+1 is expressed as:
ψ s (k+1)＝ψ s (k)+(u s (k)-R s i s (k))T s (7)
in the formulas (7) and (8), psi s Stator flux linkage vector, ψ, at time (k+1) is k+1 s (k) For the stator flux linkage vector at the current time k, u s (k) I is the reference voltage vector of the current moment k s (k) For the stator current vector at the present moment k, i s Stator current vector at time k+1, ψ, is (k+1) r (k) For the current moment k the rotor flux linkage vector,
discretizing the electromagnetic torque equation, then the electromagnetic torque T at the moment k+1 e (k+1) is represented by the following formula (9):
in a control period T s In the electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) The relationship of (2) is expressed as:
in the formula (10), T e (k) For the electromagnetic torque at the current moment k, T e An electromagnetic torque at time (k+1) is k+1, u s (k) Is the reference voltage vector at the current instant k.
Furthermore, the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency provided by the invention has the following characteristics: in step 5, a reference voltage vector u is applied s (k) Under the action of (1), the stator flux linkage vector psi of the motor at time k+1 s (k+1) and electromagnetic torque T e (k+1) should satisfy:
in the formulas (15) (16),
for the electromagnetic torque set value, ">
For a given value of the stator flux linkage,
then, in a control period T s In the electromagnetic torque increment deltat e And stator flux linkage increment delta phi s I) should satisfy:
in the formula (17), T error Representing electromagnetic torque error, ψ error Indicating the flux linkage error of the stator,
combined formula [ ]17 (10), (14) for reference voltage vector u s (k) And solving.
When (when)
When (I)>
(18)
When (when)
When (I)>
(19)
Wherein δ=θ s -θ r (20)
Further, an output reference voltage vector to be satisfied is obtained
Amplitude +.>
And angle->
Respectively is
Furthermore, the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency also comprises the following steps ofCharacteristics of the sample: wherein, when the reference voltage vector u of the current moment k s (k) Amplitude |u s (k) The I satisfies the following: i u s (k)|≥u smax At the time, |u s (k)|＝u smax ，u smax The maximum voltage which can be output by the space vector modulation module.
The invention also provides a direct torque control system of the surface-mounted permanent magnet synchronous motor with constant switching frequency, which is applied to the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency, and has the following characteristics: wherein, characterized by, include: the system comprises a three-phase voltage source inverter, a surface-mounted permanent magnet synchronous motor, a position sensor, a rotating speed signal acquisition module, a current sensor, a coordinate transformation module, an electromagnetic torque and stator flux linkage observation module, a speed controller, a reference voltage vector calculation module and a space vector modulation module, wherein the current sensor is used for acquiring three-phase stator currents of the motor; the coordinate transformation module is used for carrying out coordinate transformation on the three-phase stator current to obtain current on a two-phase static coordinate system; the position sensor is used for measuring the rotor position theta of the motor; the rotating speed signal acquisition module obtains the output rotating speed omega r The method comprises the steps of carrying out a first treatment on the surface of the The electromagnetic torque and stator flux linkage observation module is used for solving theta r 、θ s The reference voltage vector calculation module is used for obtaining the required reference voltage vector
Angle and amplitude of (a); the speed controller is used for outputting electromagnetic torque set value +.>
The space vector modulation module is used for vector +.>
Modulated to produce a drive signal.
The invention has the following functions and effects:
the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency acquires the relation between the increment of electromagnetic torque and stator flux linkage and the output voltage vector by analyzing the discrete expression of the torque and stator flux linkage so as to directly calculate the required output reference voltage vector to compensate the torque and stator flux linkage error and output the required driving signal through the space vector modulation module.
The invention directly obtains the required output reference voltage vector through the electromagnetic torque and the stator flux linkage error, avoids indirectly obtaining the output voltage vector through the PI controller in the traditional method, ensures the rapidity of motor torque response, and has simple and clear control structure and easy realization. The space vector modulation module modulates the output reference voltage vector, so that constant switching frequency is obtained, and torque and stator flux linkage fluctuation are reduced.
Drawings
FIG. 1 is a block diagram of a permanent magnet synchronous motor direct torque control system with constant switching frequency in an embodiment of the invention;
FIG. 2 is a flow chart of a method for direct torque control of a permanent magnet synchronous motor with constant switching frequency in an embodiment of the invention;
FIG. 3 is a graph of the relationship between voltage vectors, stator flux linkages and rotor flux linkages on a two-phase stationary coordinate system;
FIG. 4 is a response waveform of a conventional control method for operation of a surface-mounted permanent magnet synchronous motor, wherein (a) is a motor speed waveform, (b) is a motor torque waveform, and (c) is a motor stator flux linkage waveform;
fig. 5 shows response waveforms of operation of the surface-mounted permanent magnet synchronous motor according to an embodiment of the present invention, where (a) is a motor speed waveform, (b) is a motor torque waveform, and (c) is a motor stator flux linkage waveform.
Detailed Description
In order to make the technical means, creation characteristics, achievement purposes and effects realized by the invention easy to understand, the following embodiments are combined with the accompanying drawings to realize the direct torque control method and system for the surface-mounted permanent magnet synchronous motor with constant switching frequency.
< example >
As shown in fig. 1, an embodiment of the present invention provides a direct torque control system for a surface-mounted permanent magnet synchronous motor with constant switching frequency, which is applied to implement a direct torque control method for a surface-mounted permanent magnet synchronous motor with constant switching frequency, and the system includes: a three-phase voltage source inverter 11, a surface mounted permanent magnet synchronous motor (SPMSM) 12, a position sensor 13, a rotating speed signal acquisition module 14, a current sensor 15, a coordinate transformation module 16, a torque and stator flux linkage observation module 17, a speed controller 18, a reference voltage vector calculation module 19 and a space vector modulation module 20.
As shown in fig. 1 and fig. 2, the direct torque control method for the surface-mounted permanent magnet synchronous motor with constant switching frequency provided by the embodiment of the invention comprises the following steps:
step 2, as shown in fig. 1, the position sensor 13 is used to measure the rotor position (represented by the included angle θ) of the motor at the current time k, and the rotational speed signal acquisition module is used to implement the derivative operation of θ to the time t, so as to obtain the rotational speed signal (represented by the rotor angular velocity ω) r Indicated) and the electromagnetic torque setpoint is obtained by the speed controller 18
In FIG. 3 +.>
Representing a given value of the angular velocity of the rotor.
3-1) determining the stator flux vector psi of the motor at the current moment k by a stator flux current model s (k)：
The stator flux linkage current model is:
ψ s ＝ψ r +L s i s (2)
in the psi- s Is stator flux linkage vector, ψ r Is the rotor flux linkage vector, L s I is the stator inductance s For the stator current vector to be a vector,
fig. 3 is a graph of the relationship between the voltage vectors, stator flux linkage and rotor flux linkage on a two-phase stationary coordinate system. θ r Is the included angle between the magnetic linkage of the rotor and the alpha coordinate axis, theta s The angle between the stator flux linkage and the alpha coordinate axis is delta, the angle between the stator flux linkage and the rotor flux linkage is delta, and the angle between the voltage vector and the stator flux linkage is gamma.
As shown in fig. 3, in a two-phase stationary coordinate system with α as the horizontal axis and β as the vertical axis, the stator flux linkage component ψ for the current time k sα (k)、ψ sβ (k) The method meets the following conditions:
wherein L is s Is the stator inductance, theta r I is the included angle between the flux linkage vector of the rotor and the alpha axis sα (k)、i sβ (k) Is a component of the stator current.
From stator flux linkage component ψ sα (k)、ψ sβ (k) The stator flux linkage vector psi of the motor at the current moment k can be obtained s (k)。
3-2) passing electromagnetic torque forceSolving the electromagnetic torque T of the motor at the current moment k e (k)：
The electromagnetic torque equation is:
wherein T is e Is electromagnetic torque, ψ s I is the stator flux linkage vector s N is the stator current vector p For the motor pole pair number, the symbol x represents a vector cross multiplication operation. i.e s (k) Component i of the current which can pass through the stator sα (k)、i sβ (k) Obtaining the product.
Substituting the stator flux linkage vector psi of the current moment k in the formula (4) s (k) Stator current vector i at current time k s (k) The electromagnetic torque T of the motor at the current time k can be obtained e (k)。
Step 4, obtaining a control period T of the motor according to a dynamic mathematical model of the motor on a two-phase static coordinate system s Medium electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) Is, and stator flux linkage delta phi s Reference voltage vector u for i and current time k s (k) Is a relationship of (3).
4-1) the motor is operated in a control period T s In the electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) The relationship acquisition process of (1) is as follows:
in a two-phase stationary coordinate system, a stator flux linkage vector psi is used s And stator current vector i s As a state variable, the state equation of the motor is expressed as:
in the formulas (5) and (6),R s is stator resistance L s Is the stator inductance, ω is the rotor electrical angular velocity, ψ r For the rotor flux linkage vector, j is the virtual axis operator, u s As a vector of the voltages,
discretizing the state equations (5) and (6) of the motor to represent one control period of the motor control system as T s The stator flux linkage and stator current discrete equation at time k+1 is expressed as:
ψ s (k+1)＝ψ s (k)+(u s (k)-R s i s (k))T s (7)
in the formulas (7) and (8), psi s Stator flux linkage vector, ψ, at time (k+1) is k+1 s (k) For the stator flux linkage vector at the current time k, u s (k) I is the reference voltage vector of the current moment k s (k) For the stator current vector at the present moment k, i s Stator current vector at time k+ 1, ψ, is (k+1) r (k) For the current moment k the rotor flux linkage vector,
discretizing the electromagnetic torque equation (4), and combining the equation (7) (8), the electromagnetic torque T at the time of k+1 e (k+1) is represented as:
further, in a control period T s In the electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) The relationship of (2) is expressed as:
wherein T is e (k) For the electromagnetic torque at the current moment k, T e An electromagnetic torque at time (k+1) is k+1, u s (k) For the current time kAnd (5) a reference voltage vector.
4-2) the machine operates in a control period T s In the stator flux linkage increment delta phi s Reference voltage vector u for i and current time k s (k) The relationship acquisition process of (1) is as follows:
the stator flux linkage magnitude equation is expressed as:
in the formula, |ψ s The I is the magnitude of the stator flux linkage, the sign is the dot product operation of the vector,
discretizing the stator flux linkage amplitude equation row to represent one control period of the motor control system as T s The stator flux linkage amplitude at time k+1 is expressed as:
in the psi- s (k+1) is a stator flux linkage vector at time k+ 1, symbol is a dot product operation of the vector,
due to the fact that in one control period T s The increment of the stator flux linkage amplitude is small relative to the stator flux linkage amplitude, approximately satisfying: i psi s (k)|+|ψ s (k+1)|≈2|ψ s (k)| (13)
In the formula, |ψ s (k) The I is the amplitude of the stator flux linkage at the current moment k, and the I psi is the amplitude of the stator flux linkage at the current moment k s (k+1) | is the magnitude of the stator flux linkage at time k+ 1, and controls the period T s The square term of (2) is very small and negligible.
Then in one control period T according to equation (2) (7) s In the stator flux linkage increment delta phi s Reference voltage vector u for i and current time k s (k) The relationship of (2) is expressed as:
step 5, calculating the reference voltage vector to be output according to the electromagnetic torque error and the stator flux linkage error of the motor by a reference voltage vector calculation module 19
The method comprises the following steps:
in applying the reference voltage vector u s (k) Under the action of (1), the stator flux linkage vector psi of the motor at time k+1 s (k+1) and electromagnetic torque T e (k+1) should satisfy:
in the method, in the process of the invention,
for the electromagnetic torque set value, ">
For a given value of the stator flux linkage,
then, in a control period T s In the electromagnetic torque increment deltat e And stator flux linkage increment delta phi s I) should satisfy:
wherein T is error Representing electromagnetic torque error, ψ error Indicating the flux linkage error of the stator,
combining equations (17), (10), (14), for reference voltage vector u s (k) And solving.
Since the magnitude of the stator flux linkage increases when the reference voltage vector is at an angle gamma of-90 deg. to +90 deg. to the stator flux linkage; when the included angle gamma is in other ranges, the amplitude of the stator flux linkage is reduced, so that the following can be obtained:
when (when)
When (I)>
(18)
When (when)
When (I)>
(19)
Wherein δ=θ s -θ r (20)
Further, an output reference voltage vector to be satisfied can be obtained
Amplitude +.>
And angle->
Respectively is
Wherein when the amplitude |u s (k)|≥u smax At the time, |u s (k)|＝u smax ，u smax For space vector modulation moduleThe maximum voltage that can be output.
< simulation experiment results and analysis >
The direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency and the traditional direct torque control method of the motor are adopted for testing respectively. 4-5, FIG. 4 is a response waveform of the operation of the conventional control method surface-mounted permanent magnet synchronous motor 1000r/min, wherein 4 (a) is a motor rotation speed waveform, 4 (b) is a motor torque waveform, and 4 (c) is a motor stator flux linkage waveform; fig. 5 is a response waveform of the operation of the surface-mounted permanent magnet synchronous motor 1000r/min in the embodiment of the present invention, wherein 5 (a) is a motor rotation speed waveform, 5 (b) is a motor torque waveform, and 5 (c) is a motor stator flux linkage waveform.
As can be seen from fig. 4, in the conventional control method, the motor running torque and stator flux linkage fluctuation are both large; in the control method of the invention, as can be seen from fig. 5, the motor speed response is fast, the motor torque and stator flux linkage fluctuation are obviously reduced, the torque output is smooth and dynamic, the response is fast, and the system performance is good.
The above embodiments are preferred examples of the present invention, and are not intended to limit the scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.
Claims (3)
1. The direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency is characterized by comprising the following steps of:
step 1, collecting the motor in the following stepsThree-phase stator current i at current time k sa (k)、i sb (k)、i sc (k) Obtaining the current i of the current moment k on a two-phase static coordinate system through coordinate transformation sα (k)、i sβ (k) The coordinate transformation is a Clarke coordinate transformation:
step 2, measuring the rotor position of the motor at the current moment k, further obtaining a rotating speed signal, and obtaining an electromagnetic torque given value through a speed controller
Step 3, calculating to obtain a stator flux linkage vector psi of the motor at the current moment k according to a stator flux linkage current model of the motor and an electromagnetic torque equation s (k) Electromagnetic torque T e (k)，
The stator flux linkage current model is as follows:
ψ s ＝ψ r +L s i s (2)
in the formula (2), ψ s Is stator flux linkage vector, ψ r Is the rotor flux linkage vector, L s I is the stator inductance s For the stator current vector to be a vector,
on a two-phase stationary coordinate system with a horizontal axis alpha and a vertical axis beta, the stator flux linkage component ψ for the current time k sα (k)、ψ sβ (k) The method meets the following conditions:
in the formula (3), θ r I is the included angle between the flux linkage vector of the rotor and the alpha axis sα (k)、i sβ (k) Is a component of the stator current; from stator flux linkage component ψ sα (k)、ψ sβ (k) The stator flux linkage vector psi of the motor at the current moment k can be obtained s (k)；
The electromagnetic torque equation is:
in the formula (4), T e For electromagnetic torque, n p For the pole pair number of the motor, the symbol x represents a vector cross multiplication operation,
substituting the stator flux linkage vector psi of the current moment k in the formula (4) s (k) Stator current vector i at current time k s (k) The electromagnetic torque T of the motor at the current time k can be obtained e (k)；
Step 4, obtaining a control period T of the motor according to a dynamic mathematical model of the motor on a two-phase static coordinate system s Medium electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) Is, and stator flux linkage delta phi s Reference voltage vector u for i and current time k s (k) Is a relationship of (2);
the motor being operated in a control period T s Medium electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) The relationship acquisition process of (1) is as follows:
in a two-phase stationary coordinate system, a stator flux linkage vector psi is used s And stator current vector i s As a state variable, the state equation of the motor is expressed as:
in the formulas (5) and (6), R s Is stator resistance L s Is the stator inductance, ω is the rotor electrical angular velocity, ψ r For the rotor flux linkage vector, j is the virtual axis operator, u s As a vector of the voltages,
discretizing the state equation of the motor to represent one control period of the motor control system as T s The stator flux linkage and stator current discrete equation at time k+1 is expressed as:
ψ s (k+1)＝ψ s (k)+(u s (k)-R s i s (k))T s (7)
in the formulas (7) and (8), psi s Stator flux linkage vector, ψ, at time (k+1) is k+1 s (k) For the stator flux linkage vector at the current time k, u s (k) I is the reference voltage vector of the current moment k s (k) For the stator current vector at the present moment k, i s Stator current vector at time k+1, ψ, is (k+1) r (k) For the current moment k the rotor flux linkage vector,
discretizing the electromagnetic torque equation, then the electromagnetic torque T at the moment k+1 e (k+1) is represented by the following formula (9):
further, in a control period T s In the electromagnetic torque increment deltat e Reference voltage vector u with current time k s (k) The relationship of (2) is expressed as:
in the formula (10), T e (k) For the electromagnetic torque at the current moment k, T e An electromagnetic torque at time (k+1) is k+1, u s (k) A reference voltage vector of the current moment k;
stator flux linkage increment delta phi s Reference voltage vector u for i and current time k s (k) Relation acquisition of (a)The process is as follows:
the stator flux linkage magnitude equation is expressed as:
in the formula (11), i ψ s The I is the magnitude of the stator flux linkage, the sign is the dot product operation of the vector,
discretizing the stator flux linkage amplitude equation row to represent one control period of the motor control system as T s The stator flux linkage amplitude at time k+1 is expressed as:
in the formula (12), ψ s (k+1) is a stator flux linkage vector at time k+1, symbol is a dot product operation of the vector,
due to the fact that in one control period T s The increment of the stator flux linkage amplitude is small relative to the stator flux linkage amplitude, approximately satisfying:
|ψ s (k)|+|ψ s (k+1)|≈2|ψ s (k)| (13)
in formula (13), i ψ s (k) The I is the amplitude of the stator flux linkage at the current moment k, and the I psi is the amplitude of the stator flux linkage at the current moment k s (k+1) | is the magnitude of the stator flux linkage at time k+1, and controls the period T s The square term of (2) is very small and can be ignored, according to equation (2) (7), then in a control period T s In the stator flux linkage increment delta phi s Reference voltage vector u for i and current time k s (k) The relationship of (2) is expressed as:
step 5, calculating to obtain a reference voltage vector to be output according to the electromagnetic torque error and the stator flux linkage error of the motor
In applying the reference voltage vector u s (k) Under the action of (1), the stator flux linkage vector psi of the motor at time k+1 s (k+1) and electromagnetic torque T e (k+1) should satisfy:
T e (k+1)＝T e * (15)
in the formulas (15) (16),
for the electromagnetic torque set value, ">
For a given value of the stator flux linkage,
then, in a control period T s In the electromagnetic torque increment deltat e And stator flux linkage increment delta phi s The i should satisfy:
in the formula (17), T error Representing electromagnetic torque error, ψ error Indicating the flux linkage error of the stator,
combining equations (17), (10), (14), for reference voltage vector u s (k) Solving;
when (when)
When (I)>
When (when)
When (I)>
Wherein δ=θ s -θ r (20)
Further, an output reference voltage vector to be satisfied is obtained
Amplitude +.>
And angle->
Respectively is
Wherein θ s The angle between the stator flux linkage and the alpha coordinate axis is shown, delta is the angle between the stator flux linkage and the rotor flux linkage, and gamma is the angle between the voltage vector and the stator flux linkage;
step 6, the space vector modulation module is used for vector reference voltage
Modulating to generate a driving signal to drive the motor to operate so as to enable the switching frequency of the inverterAnd remain constant.
2. The direct torque control method for the surface-mounted permanent magnet synchronous motor with constant switching frequency as claimed in claim 1, wherein the method comprises the following steps of:
wherein, when the reference voltage vector u of the current moment k s (k) Amplitude |u s (k) The I satisfies the following: i u s (k)|≥u smax At the time, |u s (k)|＝u smax ，u smax The maximum voltage which can be output by the space vector modulation module.
3. A direct torque control system of a surface-mounted permanent magnet synchronous motor with constant switching frequency, which is applied to the direct torque control method of the surface-mounted permanent magnet synchronous motor with constant switching frequency as claimed in any one of claims 1 to 2, and is characterized by comprising the following steps: the three-phase voltage source inverter, the surface-mounted permanent magnet synchronous motor, the position sensor, the rotating speed signal acquisition module, the current sensor, the coordinate transformation module, the electromagnetic torque and stator flux linkage observation module, the speed controller, the reference voltage vector calculation module and the space vector modulation module,
the current sensor is used for collecting three-phase stator currents of the motor;
the coordinate transformation module is used for carrying out coordinate transformation on the three-phase stator current to obtain current on a two-phase static coordinate system;
the position sensor is used for measuring the rotor position theta of the motor;
the rotating speed signal acquisition module obtains the output rotating speed omega r ；
The electromagnetic torque and stator flux linkage observation module is used for solving theta r 、θ s The amplitude of the stator flux linkage and the electromagnetic torque,
the reference voltage vector calculation module is used for obtaining the required reference voltage vector
Angle and amplitude of (a);
the speed controller is used for inputtingGiving the electromagnetic torque set value
The space vector modulation module is used for vector reference voltage
Modulated to produce a drive signal. />
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2164165A1 (en) * | 2008-09-16 | 2010-03-17 | ABB Research Ltd. | Method and apparatus for reducing torque ripple in permanent magnet synchronous machines |
| CN102001167A (en) * | 2010-09-07 | 2011-04-06 | 华南理工大学 | Plunger pump type hydraulic injection moulding machine system driven by servo motor and control method thereof |
| CN103684169A (en) * | 2013-11-19 | 2014-03-26 | 西安交通大学 | Dead-beat based direct torque control method for permanent magnet synchronous motor |
| CN106100478A (en) * | 2016-07-06 | 2016-11-09 | 扬州大学 | A kind of control method of permagnetic synchronous motor |
| WO2017159072A1 (en) * | 2016-03-15 | 2017-09-21 | 株式会社 日立産機システム | Motor control device and drive system |
| CN107834933A (en) * | 2017-11-18 | 2018-03-23 | 武汉科技大学 | One kind is based on torque ring auto-disturbance rejection technology direct torque control method for permanent magnetic synchronous electric machine |
| CN108092585A (en) * | 2017-12-22 | 2018-05-29 | 上海电机学院 | A kind of direct Torque Control of no magnetic linkage ring |
| CN108448982A (en) * | 2018-04-08 | 2018-08-24 | 天津工业大学 | A kind of Direct Torque Control based on space voltage vector prediction |
| CN109861605A (en) * | 2019-01-29 | 2019-06-07 | 东南大学 | A kind of permanent magnet synchronous motor dead beat torque prediction control method |
| CN109936320A (en) * | 2019-04-26 | 2019-06-25 | 福州大学 | A kind of bi-motor series connection Direct Torque Control based on duty ratio modulation |
| CN110620539A (en) * | 2019-09-25 | 2019-12-27 | 南京航空航天大学 | Direct torque control optimization method for open-winding motor under variable bus voltage working condition |
| CN110784145A (en) * | 2019-11-18 | 2020-02-11 | 南通大学 | Permanent magnet synchronous motor full-speed domain model prediction flux linkage control method |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103066910B (en) * | 2012-12-19 | 2015-04-15 | 天津大学 | Direct torque control method capable of hindering torque impulse |
-
2020
- 2020-03-26 CN CN202010223662.0A patent/CN111342726B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2164165A1 (en) * | 2008-09-16 | 2010-03-17 | ABB Research Ltd. | Method and apparatus for reducing torque ripple in permanent magnet synchronous machines |
| CN102001167A (en) * | 2010-09-07 | 2011-04-06 | 华南理工大学 | Plunger pump type hydraulic injection moulding machine system driven by servo motor and control method thereof |
| CN103684169A (en) * | 2013-11-19 | 2014-03-26 | 西安交通大学 | Dead-beat based direct torque control method for permanent magnet synchronous motor |
| WO2017159072A1 (en) * | 2016-03-15 | 2017-09-21 | 株式会社 日立産機システム | Motor control device and drive system |
| CN106100478A (en) * | 2016-07-06 | 2016-11-09 | 扬州大学 | A kind of control method of permagnetic synchronous motor |
| CN107834933A (en) * | 2017-11-18 | 2018-03-23 | 武汉科技大学 | One kind is based on torque ring auto-disturbance rejection technology direct torque control method for permanent magnetic synchronous electric machine |
| CN108092585A (en) * | 2017-12-22 | 2018-05-29 | 上海电机学院 | A kind of direct Torque Control of no magnetic linkage ring |
| CN108448982A (en) * | 2018-04-08 | 2018-08-24 | 天津工业大学 | A kind of Direct Torque Control based on space voltage vector prediction |
| CN109861605A (en) * | 2019-01-29 | 2019-06-07 | 东南大学 | A kind of permanent magnet synchronous motor dead beat torque prediction control method |
| CN109936320A (en) * | 2019-04-26 | 2019-06-25 | 福州大学 | A kind of bi-motor series connection Direct Torque Control based on duty ratio modulation |
| CN110620539A (en) * | 2019-09-25 | 2019-12-27 | 南京航空航天大学 | Direct torque control optimization method for open-winding motor under variable bus voltage working condition |
| CN110784145A (en) * | 2019-11-18 | 2020-02-11 | 南通大学 | Permanent magnet synchronous motor full-speed domain model prediction flux linkage control method |
Non-Patent Citations (1)
| Title |
|---|
| 宁博文.基于占空比技术的PMSM 直接转矩控制.高技术通讯.2019,1095-1101. * |
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