CN114006557B - Permanent magnet synchronous motor mechanical parameter identification method based on extended sliding mode observer - Google Patents

Permanent magnet synchronous motor mechanical parameter identification method based on extended sliding mode observer Download PDF

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CN114006557B
CN114006557B CN202111165630.0A CN202111165630A CN114006557B CN 114006557 B CN114006557 B CN 114006557B CN 202111165630 A CN202111165630 A CN 202111165630A CN 114006557 B CN114006557 B CN 114006557B
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sliding mode
equation
permanent magnet
observer
disturbance
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CN114006557A (en
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刘朝华
廖忠
陈磊
吕明阳
李小花
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Hunan University of Science and Technology
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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
    • H02P21/0003—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control
    • H02P21/0007—Control strategies in general, e.g. linear type, e.g. P, PI, PID, using robust control using sliding mode control
    • 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
    • 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
    • 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
    • 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
    • H02P6/34—Modelling or simulation for control purposes
    • 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

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Control Of Ac Motors In General (AREA)
  • Control Of Electric Motors In General (AREA)

Abstract

The invention discloses a permanent magnet synchronous motor mechanical parameter identification method based on an extended sliding mode observer, which comprises the following steps: establishing a mathematical model of the surface-mounted permanent magnet synchronous motor and adopting vector control through coordinate transformation; designing an extended sliding mode mechanical parameter view and determining observer related parameters; and observing system disturbance information by using the proposed extended sliding mode observer and extracting damping coefficient, moment of inertia and load torque from the system disturbance information. Firstly, taking friction coefficient parameter errors, rotational inertia parameter errors and load torque system disturbance as expansion system states, establishing an expansion state equation for designing an expansion sliding mode observer, wherein the expansion sliding mode observer can track the system states in real time and soften sliding mode variable structure control signals; therefore, the output of the extended sliding mode observer can be directly used for mechanical parameter estimation without generating phase lag, and the self-tuning control of the permanent magnet synchronous motor system is realized by correctly estimating the mechanical parameter in real time, so that the optimal control is realized.

Description

Permanent magnet synchronous motor mechanical parameter identification method based on extended sliding mode observer
Technical Field
The invention relates to the field of motor control, in particular to a permanent magnet synchronous motor mechanical parameter identification method based on an extended sliding mode observer.
Background
The permanent magnet synchronous motor has the advantages of simple structure, small volume, high efficiency, high torque-current ratio, high power density and the like, and the alternating current permanent magnet speed regulating system formed by the permanent magnet synchronous motor has more excellent performance compared with the speed regulating system formed by other motors. The vector control technology is a control method commonly used in a permanent magnet synchronous motor system, and decoupling of electromagnetic torque and magnetic flux of the system can be achieved through vector control, so that influence caused by nonlinearity and strong coupling of an alternating current motor is avoided, and the system has high tracking capacity, high tracking precision and good robustness. However, for more complicated working conditions, the dynamic performance of the system is reduced due to the parameter change of the system and the unknown disturbance outside, and at the moment, the controller parameter should be adjusted in time to inhibit the system disturbance caused by the parameter change, so that the good dynamic performance and steady-state performance of the system are ensured. The adjustment of the controller parameters can come from practical experience, but the adjustment methods do not have real-time performance and cannot be applied to working conditions with frequent parameter changes. Compared with the prior art, the controller parameter self-tuning technology can adjust parameters on line, has high instantaneity, but the adjusting effect of the method depends on the accuracy of mechanical parameters such as load torque, moment of inertia and the like. Therefore, the system needs to include a mechanism for accurately identifying the system parameters, and the controller parameters are adjusted in time according to the identification values, so that the influence of disturbance on the system can be reduced or even eliminated.
The mechanical parameters of the permanent magnet synchronous motor system mainly refer to load torque, moment of inertia, damping coefficient and the like, wherein the identification method of the moment of inertia can be generally divided into two main types: an off-line identification method and an on-line identification method.
The off-line identification method comprises a power-off deceleration method, an orthogonal integration method, a single steel wire torsion oscillation method and the like, but the methods cannot take the change of parameters of the motor in actual engineering into consideration, and are generally only used for initial value setting of motor control, and the main defects are non-real-time. The online identification eliminates the defect of offline identification by monitoring parameters in real time, and accords with the actual control requirement, and the negative influence is that a large amount of data needs to be stored and calculated in the working process, so that the requirement on a computer is higher and higher, and the accuracy of identification is influenced to a certain extent.
The online identification method comprises a state observer, extended Kalman filtering, model reference self-adaptive identification, least square identification and the like. The parameter identification method based on the model reference self-adaptive system is simple and easy to implement and is applied to a plurality of practical engineering applications, but the method cannot be used for estimating the load torque in real time. The model reference adaptive method can estimate parameters by continuously adjusting the adaptive law or function cost, however, it is difficult to be practically applied due to the complexity of practical implementation and the sensitivity of the adaptive gain. The extended kalman filter algorithm takes the mechanical parameter as one of the system variables and takes it as the direct output of the extended kalman filter. The recursive least square algorithm iteratively solves least square estimation when converging, and the least square estimation has larger dependence on initial conditions. Although the recursive least squares method can be used to estimate parameters of the permanent magnet synchronous motor control system, a longer estimation time is required in the estimation process. Therefore, this method is limited in scientific practice and practical industrial manufacturing. When the load torque of the permanent magnet synchronous motor is identified, the moment of inertia is defined as an already known parameter by a disturbance observer, but in actual production practice, the two variables are generally unknown, and in this case, a good identification result is difficult to realize.
Disclosure of Invention
In order to solve the technical problems, the invention provides a permanent magnet synchronous motor mechanical parameter identification method which can track the state of a system in real time, can be directly used for mechanical parameter estimation and does not generate phase lag.
The technical scheme for solving the problems is as follows: a permanent magnet synchronous motor mechanical parameter identification method based on an extended sliding mode observer comprises the following steps:
1) Establishing a mathematical model of the surface-mounted permanent magnet synchronous motor, and adopting vector control through coordinate transformation: firstly, establishing a mathematical model under an A-B-C three-phase static coordinate system to obtain a voltage equation, a flux linkage equation, a torque equation and a mechanical motion equation of each phase, and then sequentially obtaining a mathematical model under an alpha-beta two-phase static coordinate system and a d-q axis two-phase rotating coordinate system through Clark conversion and Park conversion to realize complete decoupling of exciting current and torque current so as to facilitate control;
2) Designing an extended sliding mode observer and determining observer related parameters: according to a mechanical motion equation of the PMSM, taking damping coefficient parameter errors, moment of inertia parameter errors and load torque system disturbance as an extended system state, establishing an extended state equation for designing an extended sliding mode observer, and ensuring the stability of the observer by considering a Lyapunov function;
3) Observing system disturbance information by using the proposed extended sliding mode observer and extracting damping coefficient, moment of inertia and load torque from the system disturbance information: firstly, the permanent magnet synchronous motor is operated at two different steady-state speeds, damping coefficients are estimated by utilizing measured speed information and estimated disturbance, then the permanent magnet synchronous motor is operated at two different constant acceleration or constant deceleration respectively to estimate the moment of inertia, and finally, the damping coefficients and the moment of inertia are directly used for estimating load torque.
The method for identifying the mechanical parameters of the permanent magnet synchronous motor based on the extended sliding mode observer comprises the following specific processes:
firstly, establishing a mathematical model under an A-B-C three-phase static coordinate system, wherein the voltage equation of the A-B-C three-phase static coordinate system is as follows:
wherein R is s Is stator resistance, U A 、U B 、U C For stator three-phase voltage, i A 、i B 、i C Is stator three-phase current, ψ sA 、Ψ sB 、Ψ sC The vector form of the full flux linkage of the three phases of the stator is as follows:wherein psi is s U, which is the stator flux linkage S Is the stator voltage; i.e s Is the stator current;
the flux linkage equation is:
wherein, ψ is fA 、Ψ fB 、Ψ fC I is the flux linkage of the permanent magnet magnetic field and the three intersecting links of the stator sA 、i sB 、i sC Respectively represent A, B, C three-phase stator currents, L s For the stator to synchronize the inductance,L A ＝L B ＝L C ＝L sσ +L ml wherein L is A 、L B 、L C For each phase sense, L ml Exciting an inductor for each phase; l (L) Sσ Leakage inductance for each phase;
torque equation:
electromagnetic torque is believed to be the result of interactions between the stator, rotor and armature, expressed as:
wherein p is the pole pair number, T e Is electromagnetic torque, ψ f For linking permanent magnet field and stator, ψ is the linkage s Is a stator flux linkage;
mechanical equation of motion:
ω m for the mechanical angular velocity of the rotor, T L The torque is load torque, J is rotational inertia, and B is a damping coefficient of the motor;
and then the mathematical model under the d-q axis two-phase rotation coordinate system is finally obtained through Clark conversion and Park conversion in sequence, so that the complete decoupling of exciting current and torque current is realized, and vector control is performed:
flux linkage equation:
wherein, ψ is d 、Ψ q L is the AC-DC axis component of the stator flux linkage d 、L q I is the component of the stator inductance in the d and q axes d 、i q Stator currents of d and q axes;
voltage equation:
in U d 、U q Respectively the alternating-direct axis component, omega of the stator voltage e Representing the rotor angular velocity;
torque equation:
wherein L is d 、L q The inductance value is the direct axis and the quadrature axis; it can be seen that decoupling of the torque is achieved at the d-q axis, the torque equation being as follows:
in the above method for identifying mechanical parameters of permanent magnet synchronous motor based on extended sliding mode observer, in the step 2), the dynamic equation of the motor is expressed as follows:
wherein B is 0 、J 0 Is a rough estimate of the real parameters, Δb, Δj is the parameter error between the real system and its rough estimate, moment of inertia j=j 0 +Δj, damping coefficient b=b 0 +ΔB，Omega is the rotation speed, d represents disturbance including parameter error and load disturbance;
regarding the disturbance d as an extended system state, for parameter estimation, the extended sliding mode observer is designed to:
wherein,is an estimate of the disturbance,/->Is the estimated value of the speed, m is the sliding mode parameter, u smo Representing a sliding mode observer signal and u smo =η·sgn (S), η is a real number, S is a sliding mode plane and is negative, designed as +.>
The error equation is obtained at this time as follows:
error ofIntermediate quantity->
In order to ensure the occurrence of the sliding mode, the stable condition of the sliding mode variable structure must be satisfied; thus, consider the following lyapunov function: v=0.5 s 2 V and s represent the relation quantity of speed and time in a motion system, and the time t is differentiated by V to obtain:namely:
in order to ensure the stability of the extended sliding mode observer, a stability condition must be satisfiedI.e. eta<-|e 2 -B 0 e 1 In practical application, the following parameter adaptive law is adopted: η= -l|e 2 -B 0 e 1 |,l>1, l is the safety factor of the sliding mode; error e 1 And its derivative->Can converge to zero along a sliding mode that occurs within a limited time, i.e. +.>Therefore, the error equation is reduced to +.>I.e. < ->Thus e 2 The results of (2) are expressed as: e, e 2 ＝e -mt [C+∫r·e mt dt]Where e is a mathematical constant and C is a constant to ensure a disturbance estimation error e 2 Converging to zero, selecting the sliding mode parameter as the parameter m of disturbance estimation>0; thus, the choice of extended sliding mode observer parameters is constrained by η and m;
velocity after occurrence of slip modeThe observer equation is reduced to
Thus, the equation is obtained:the observer is equivalent to a low-pass filter after the sliding mode occurs; it can be seen that the disturbance observation effect of the extended sliding mode observer is equivalent to the output of the filtering actual system disturbance.
In the above method for identifying mechanical parameters of a permanent magnet synchronous motor based on an extended sliding mode observer, in the step 3), the permanent magnet synchronous motor is operated at two different stable speeds, so as to estimate the damping coefficient B;
when the motor is running at a first steady-state rotational speed ω (t), based on the extended sliding mode observer and the disturbance d, the following disturbance estimate is obtained:
estimated values of Δb and Δj, respectively;
then, after a time delay τ, the disturbance of the second steady speed ω (t+τ) is estimated as follows,
when the permanent magnet synchronous motor control system reaches the steady-state rotating speed, the load torque T L Consider a constant, the subtraction of the two above formulas:
thus, the first and second substrates are bonded together,writing:
thus, an estimated parameter is obtainedThe method comprises the following steps:
in the above method for identifying mechanical parameters of permanent magnet synchronous motor based on extended sliding mode observer, in the step 3), when the motor is in a first constant acceleration state ac 1 During operation, based on the extended sliding mode observer and the disturbance equation, the estimated value B obtained in the previous step is introduced, and the following disturbance estimation can be obtained:
then, by ensuring that two different constant accelerations correspond exactly to two different time periods, respectively, after a time delay τ, a second constant acceleration state ac 2 The interference estimate of (2) is given as follows:
the two formulas are subtracted and arranged to obtain estimated parameters
In the above method for identifying mechanical parameters of permanent magnet synchronous motor based on extended sliding mode observer, in the step 3), when parameters B and J are precisely estimated, the original estimation B in the state equation 0 And J 0 Estimated parametersAndinstead, the extended sliding mode observer is then rewritten as:
at this time, the updated estimated disturbanceExpressed as: />It can be seen that the updated extended sliding mode observer has the ability to estimate the load torque, and therefore, in practical applications, the proposed extended sliding mode observer is used to estimate B and J, or the load torque T is estimated online in real time given B and J L 。
The invention has the beneficial effects that:
1. according to the invention, according to the problem that the control performance of the permanent magnet synchronous motor is affected due to the fact that the load condition is changeable in an actual permanent magnet synchronous motor control system, the mechanical parameters of the permanent magnet synchronous motor control system can be observed in real time by the proposed extended sliding mode observer and fed back to the controller to adjust the parameters in time, so that system disturbance is suppressed, and good dynamic performance and steady state performance of the system are ensured.
2. The extended sliding mode observer provided by the invention can be equivalent to a low-pass filter after the sliding mode occurs, and the disturbance observation effect is equivalent to the output of the disturbance of a filtering actual system. The cut-off frequency of the low-pass filter is m, and the low-pass filter can be designed arbitrarily according to the buffeting suppression requirement of an observer. Therefore, the output of the observer does not contain sliding mode buffeting caused by a low-pass filter and can be directly used for system control.
3. The invention can reduce the error value of the observer to zero in effective time, has stronger anti-interference capability to external disturbance, simple structure and low sensitivity to system parameter change.
Drawings
Fig. 1 is a block diagram of a permanent magnet synchronous motor mechanical parameter estimation.
FIG. 2 is a schematic diagram of an extended sliding mode observer.
Fig. 3 is a schematic diagram of an equivalent low pass filter of the extended sliding mode observer.
Fig. 4 is a schematic diagram of a mechanical parameter estimation.
Fig. 5 is a graph of experimental results of damping coefficients identified by an extended sliding mode observer.
Fig. 6 is a graph of experimental results of moment of inertia identified by an extended sliding mode observer.
Fig. 7 is a graph of experimental results of the load torque identified by the extended sliding mode observer.
Detailed Description
The invention is further described below with reference to the drawings and examples.
As shown in fig. 1, a permanent magnet synchronous motor mechanical parameter identification method based on an extended sliding mode observer comprises the following steps:
1) Establishing a mathematical model of the surface-mounted permanent magnet synchronous motor, and adopting vector control through coordinate transformation: firstly, establishing a mathematical model under an A-B-C three-phase static coordinate system to obtain a voltage equation, a flux linkage equation, a torque equation and a mechanical motion equation of each phase, and then sequentially obtaining the mathematical model under an alpha-beta two-phase static coordinate system and a d-q axis two-phase rotating coordinate system through Clark conversion and Park conversion to realize complete decoupling of exciting current and torque current so as to facilitate control.
The specific process of the step 1) is as follows:
firstly, establishing a mathematical model under an A-B-C three-phase static coordinate system, wherein the voltage equation of the A-B-C three-phase static coordinate system is as follows:
wherein R is s Is stator resistance, U A 、U B 、U C For stator three-phase voltage, i A 、i B 、i C Is stator three-phase current, ψ sA 、Ψ sB 、Ψ sC The vector form of the full flux linkage of the three phases of the stator is as follows:wherein psi is s U, which is the stator flux linkage S Is the stator voltage; i.e s Is the stator current;
the flux linkage equation is:
wherein, ψ is fA 、Ψ fB 、Ψ fC I is the flux linkage of the permanent magnet magnetic field and the three intersecting links of the stator sA 、i sB 、i sC Respectively represent A, B, C three-phase stator currents, L s For the stator to synchronize the inductance,since the distribution of the air gap is uniform, the rotor does not affect the self inductance and the mutual inductance of the stator and A, B, C phases, so they are constant. L (L) A ＝L B ＝L C ＝L sσ +L ml Wherein L is A 、L B 、L C For each phase sense, L ml Exciting an inductor for each phase; l (L) Sσ Leakage inductance for each phase;
torque equation:
electromagnetic torque is believed to be the result of interactions between the stator, rotor and armature, expressed as:
wherein p is the pole pair number, T e Is electromagnetic torque, ψ f Is a permanent magnet magnetic field and a statorInterlinked flux linkage, ψ s Is a stator flux linkage;
mechanical equation of motion:
ω m for the mechanical angular velocity of the rotor, T L The torque is load torque, J is rotational inertia, and B is a damping coefficient of the motor;
and then the mathematical model under the d-q axis two-phase rotation coordinate system is finally obtained through Clark conversion and Park conversion in sequence, so that the complete decoupling of exciting current and torque current is realized, and vector control is performed:
flux linkage equation:
wherein, ψ is d 、Ψ q L is the AC-DC axis component of the stator flux linkage d 、L q I is the component of the stator inductance in the d and q axes d 、i q Stator currents of d and q axes;
voltage equation:
in U d 、U q Respectively the alternating-direct axis component, omega of the stator voltage e Indicating the rotor angular velocity.
Torque equation:
wherein L is d 、L q The inductance value is the direct axis and the quadrature axis; it can be seen that decoupling of the torque is achieved at the d-q axis, the torque equation being as follows:
2) Designing an extended sliding mode observer and determining observer related parameters: according to the mechanical motion equation of the PMSM, damping coefficient parameter errors, moment of inertia parameter errors and load torque system disturbance are used as an extended system state, an extended state equation is established and used for designing an extended sliding mode observer, and stability of the observer is ensured by considering a Lyapunov function.
The kinetic equation of the motor is expressed as follows:
wherein B is 0 、J 0 Is a rough estimate of the real parameters, Δb, Δj is the parameter error between the real system and its rough estimate, moment of inertia j=j 0 +Δj, damping coefficient b=b 0 +Δb, ω is rotational speed, d represents disturbances including parameter errors and load disturbances;
regarding the disturbance d as an extended system state, for parameter estimation, the extended sliding mode observer is designed to:
wherein,is an estimate of the disturbance,/->Is the estimated value of the speed, m is the sliding mode parameter, u smo Representing a sliding mode observer signal and u smo =η·sgn (S), η is a real number, S is a sliding mode plane and is negative, designed as +.>
The error equation is obtained at this time as follows:
error of
In order to ensure the occurrence of the sliding mode, the parameters of the observer must be reasonably selected, namely, the stable condition of the sliding mode variable structure must be satisfied; thus, consider the following lyapunov function: v=0.5 s 2 V and s represent the relation quantity of speed and time in a motion system, and the time t is differentiated by V to obtain:namely:
in order to ensure the stability of the extended sliding mode observer, a stability condition must be satisfiedI.e. eta<-|e 2 -B 0 e 1 In practical application, the following parameter adaptive law is adopted: η= -l|e 2 -B 0 e 1 |,l>1, l is the safety factor of the sliding mode; typically, l=2 is sufficient to guarantee the stability of the observer.
As can be seen, error e 1 And its derivativeCan converge to zero along a sliding mode occurring in a limited time, i.eTherefore, the error equation is reduced to +.>I.e. < ->Thus e 2 The results of (2) are expressed as: e, e 2 ＝e -mt [C+∫r·e mt dt]Where e is a mathematical constant and C is a constant to ensure a disturbance estimation error e 2 Converging to zero, selecting the sliding mode parameter as the parameter m of disturbance estimation>0; thus, the choice of extended sliding mode observer parameters is constrained by η and m;
as shown in fig. 2, the post-slip mode velocity occursThe observer equation is reduced to
Thus, the equation is obtained:the observer is equivalent to a low-pass filter after the sliding mode occurs, as shown in fig. 3; it can be seen that the disturbance observation effect of the extended sliding mode observer is equivalent to the output of the filtering actual system disturbance. Since the cut-off frequency of the low-pass filter is the same as the value of m, the low-pass filter can be arbitrarily designed according to the buffeting suppression requirement of the observer. Therefore, the output of the observer does not contain sliding mode buffeting caused by a low-pass filter and can be directly used for system control.
3) Observing system disturbance information by using the proposed extended sliding mode observer and extracting damping coefficient, moment of inertia and load torque from the system disturbance information: firstly, the permanent magnet synchronous motor is operated at two different steady-state speeds, damping coefficients are estimated by utilizing measured speed information and estimated disturbance, then the permanent magnet synchronous motor is operated at two different constant acceleration or constant deceleration respectively to estimate the moment of inertia, and finally, the damping coefficients and the moment of inertia are directly used for estimating load torque.
As shown in fig. 4, when the motor is operating at a first steady-state rotational speed ω (t), based on the extended sliding mode observer and the disturbance d, the following disturbance estimates are obtained:
estimated values of Δb and Δj, respectively;
then, after a time delay τ, the disturbance of the second steady speed ω (t+τ) is estimated as follows,
when the permanent magnet synchronous motor control system reaches the steady-state rotating speed, the load torque T L Consider a constant, the subtraction of the two above formulas:
thus, the first and second substrates are bonded together,writing:
thus, an estimated parameter is obtainedThe method comprises the following steps:
when the motor is in a first constant acceleration state ac 1 Run-timeBased on the extended sliding mode observer and the disturbance equation, the estimated value B obtained in the previous step is introduced, and the following disturbance estimation can be obtained:
then, by ensuring that two different constant accelerations correspond exactly to two different time periods, respectively, after a time delay τ, a second constant acceleration state ac 2 The interference estimate of (2) is given as follows:
the two formulas are subtracted and arranged to obtain estimated parameters
When parameters B and J are accurately estimated, the original estimate B in the state equation 0 And J 0 Estimated parametersAnd->Instead, the extended sliding mode observer is then rewritten as:
at this time, the updated estimated disturbanceExpressed as: />It can be seen that the updated extended sliding mode observer has the ability to estimate the load torque, and therefore, in practical applications, the proposed extended sliding mode observer is used to estimate B and J, or the load torque T is estimated online in real time given B and J L 。
Simulating the mechanical parameter identification method by using a Matlab simulation platform, wherein a system template adopts a vector control structure, and i is selected d The identification results of the three parameters are shown in fig. 5, 6 and 7 respectively according to the control strategy of=0, and the identification results are basically consistent with the actual values by comparing the actual data of the motor. Thereby verifying the validity of the mechanical parameter identification algorithm.
In summary, according to the invention, according to the actual permanent magnet synchronous motor control system, aiming at the problem that the control performance of the permanent magnet synchronous motor is affected due to the changeable load condition, the proposed extended mechanical parameter sliding mode observer can observe the mechanical parameters of the permanent magnet synchronous motor in real time and feed back the mechanical parameters to the controller to adjust the parameters in time, so as to inhibit system disturbance, ensure good dynamic performance and stability of the system, and the identification result does not contain sliding mode buffeting caused by a filter, thus the system control system can be directly used for system control and has certain anti-interference capability; compared with the prior art, the mechanical output parameter identification based on the extended sliding mode observer provides a very effective way for improving the self-control of the permanent magnet synchronous motor under the condition of variable load, and can be widely applied to a series of complex systems such as an electric automobile, a flywheel energy storage system, a wind energy conversion system and the like.

Claims (6)

1. The permanent magnet synchronous motor mechanical parameter identification method based on the extended sliding mode observer is characterized by comprising the following steps of:
1) Establishing a mathematical model of the surface-mounted permanent magnet synchronous motor, and adopting vector control through coordinate transformation: firstly, establishing a mathematical model under an A-B-C three-phase static coordinate system to obtain a voltage equation, a flux linkage equation, a torque equation and a mechanical motion equation of each phase, and then sequentially obtaining a mathematical model under an alpha-beta two-phase static coordinate system and a d-q axis two-phase rotating coordinate system through Clark conversion and Park conversion to realize complete decoupling of exciting current and torque current so as to facilitate control;
2) Designing an extended sliding mode observer and determining observer related parameters: according to a mechanical motion equation of the PMSM, taking damping coefficient parameter errors, moment of inertia parameter errors and load torque system disturbance as an extended system state, establishing an extended state equation for designing an extended sliding mode observer, and ensuring the stability of the observer by considering a Lyapunov function;
3) Observing system disturbance information by using the proposed extended sliding mode observer and extracting damping coefficient, moment of inertia and load torque from the system disturbance information: firstly, the permanent magnet synchronous motor is operated at two different steady-state speeds, damping coefficients are estimated by utilizing measured speed information and estimated disturbance, then the permanent magnet synchronous motor is operated at two different constant acceleration or constant deceleration respectively to estimate the moment of inertia, and finally, the damping coefficients and the moment of inertia are directly used for estimating load torque.
2. The method for identifying the mechanical parameters of the permanent magnet synchronous motor based on the extended sliding mode observer according to claim 1, wherein the specific process of the step 1) is as follows:
firstly, establishing a mathematical model under an A-B-C three-phase static coordinate system, wherein the voltage equation of the A-B-C three-phase static coordinate system is as follows:
wherein R is s Is stator resistance, U A 、U B 、U C For stator three-phase voltage, i A 、i B 、i C Is stator three-phase current, ψ sA 、Ψ sB 、Ψ sC The vector form of the full flux linkage of the three phases of the stator is as follows:wherein psi is s U, which is the stator flux linkage S Is the stator voltage; i.e s Is the stator current;
the flux linkage equation is:
wherein, ψ is fA 、Ψ fB 、Ψ fC I is the flux linkage of the permanent magnet magnetic field and the three intersecting links of the stator sA 、i sB 、i sC Respectively represent A, B, C three-phase stator currents, L s For the stator to synchronize the inductance,L A ＝L B ＝L C ＝L sσ +L ml wherein L is A 、L B 、L C For each phase sense, L ml Exciting an inductor for each phase; l (L) Sσ Leakage inductance for each phase;
torque equation:
electromagnetic torque is believed to be the result of interactions between the stator, rotor and armature, expressed as:
wherein p is the pole pair number, T e Is electromagnetic torque, ψ f For linking permanent magnet field and stator, ψ is the linkage s Is a stator flux linkage;
mechanical equation of motion:
ω m for the mechanical angular velocity of the rotor, T L The torque is the load torque, J is the moment of inertia, and B is the damping system of the motorA number;
and then the mathematical model under the d-q axis two-phase rotation coordinate system is finally obtained through Clark conversion and Park conversion in sequence, so that the complete decoupling of exciting current and torque current is realized, and vector control is performed:
flux linkage equation:
wherein, ψ is d 、Ψ q L is the AC-DC axis component of the stator flux linkage d 、L q I is the component of the stator inductance in the d and q axes d 、i q Stator currents of d and q axes;
voltage equation:
in U d 、U q Respectively the alternating-direct axis component, omega of the stator voltage e Representing the rotor angular velocity;
torque equation:
wherein L is d 、L q The inductance value is the direct axis and the quadrature axis; it can be seen that decoupling of the torque is achieved at the d-q axis, the torque equation being as follows:
3. the method for identifying mechanical parameters of the permanent magnet synchronous motor based on the extended sliding mode observer according to claim 2, wherein in the step 2), the kinetic equation of the motor is expressed as follows:
wherein B is 0 、J 0 Is a rough estimate of the real parameters, moment of inertia j=j 0 +Δj, damping coefficient b=b 0 +Δb, Δb, Δj are parameter errors between the real system and its rough estimate, ω is rotational speed, d represents disturbances, including parameter errors and load disturbances;
regarding the disturbance d as an extended system state, for parameter estimation, the extended sliding mode observer is designed to:
wherein,is an estimate of the disturbance,/->Is the estimated value of the speed, m is the sliding mode parameter, u smo Representing a sliding mode observer signal and u smo =η·sgn (S), η is a real number, S is a sliding mode plane and is negative, designed as +.>The error equation is obtained at this time as follows:
error ofIntermediate quantity->
In order to ensure the occurrence of the sliding mode, the stable condition of the sliding mode variable structure must be satisfied; thus, consider the following lyapunov function: v=0.5 s 2 V and s represent the relation quantity of speed and time in a motion system, and the time t is differentiated by V to obtain:namely:
in order to ensure the stability of the extended sliding mode observer, a stability condition must be satisfiedThus, eta<-|e 2 -B 0 e 1 In practical application, the following parameter adaptive law is adopted: η= -l|e 2 -B 0 e 1 |,l>1, l is the safety factor of the sliding mode; error e 1 And its derivative->Can converge to zero along a sliding mode that occurs within a limited time, i.e. +.>Therefore, the error equation is reduced to +.>I.e. < ->Thus e 2 The results of (2) are expressed as: e, e 2 ＝e -mt [C+∫r·e mt dt]Where e is a mathematical constant and C is a constant to ensure a disturbance estimation error e 2 Convergence ofTo zero, selecting the sliding mode parameter as the parameter m of disturbance estimation>0; thus, the choice of extended sliding mode observer parameters is constrained by η and m;
velocity after occurrence of slip modeThe observer equation is reduced to
Thus, the equation is obtained:the observer is equivalent to a low-pass filter after the sliding mode occurs; it can be seen that the disturbance observation effect of the extended sliding mode observer is equivalent to the output of the filtering actual system disturbance.
4. The method for identifying mechanical parameters of a permanent magnet synchronous motor based on an extended sliding mode observer according to claim 3, wherein in the step 3), the permanent magnet synchronous motor is operated at two different stable speeds, so as to estimate the damping coefficient B;
when the motor is running at a first steady-state rotational speed ω (t), based on the extended sliding mode observer and the disturbance d, the following disturbance estimate is obtained:
estimated values of Δb and Δj, respectively;
then, after a time delay τ, the disturbance of the second steady speed ω (t+τ) is estimated as follows,
when the permanent magnet synchronous motor control system reaches the steady-state rotating speed, the load torque T L Consider a constant, the subtraction of the two above formulas:
thus, the first and second substrates are bonded together,writing:
thus, an estimated parameter is obtainedThe method comprises the following steps:
5. the method for identifying mechanical parameters of permanent magnet synchronous motor based on extended sliding mode observer according to claim 4, wherein in the step 3), when the motor is in the first constant acceleration state ac 1 During operation, based on the extended sliding mode observer and the disturbance equation, the estimated value B obtained in the previous step is introduced, and the following disturbance estimation can be obtained:
then, by ensuring that two different constant accelerations correspond exactly to two different time periods, respectively, one is passedAfter a time delay τ, a second constant acceleration state ac 2 The interference estimate of (2) is given as follows:
the two formulas are subtracted and arranged to obtain estimated parameters
6. The method for identifying mechanical parameters of permanent magnet synchronous motor based on extended sliding mode observer according to claim 5, wherein in the step 3), when parameters B and J are precisely estimated, the original estimate B in the state equation is 0 And J 0 Estimated parametersAnd->Instead, the extended sliding mode observer is then rewritten as:
at this time, the updated estimated disturbanceExpressed as: />It can be seen from this that the updated extended sliding-mode viewThe measuring device has the capability of estimating the load torque, so in practical application, the proposed extended sliding mode observer is used for estimating B and J, or estimating the load torque T in real time on line under the condition that B and J are known L 。
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105827168A (en) * 2016-05-10 2016-08-03 华中科技大学 PMSM control method and system based on sliding mode observation
WO2018077593A1 (en) * 2016-10-27 2018-05-03 Siemens Aktiengesellschaft Method for determining a deadzone angle of a backlash in a mechanical drive-train system, method for controlling a drive motor controller as well as drive-train system
CN110557070A (en) * 2019-09-30 2019-12-10 山东深川变频科技股份有限公司 permanent magnet synchronous motor parameter identification method based on second-order sliding-mode observer

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100237817A1 (en) * 2009-03-23 2010-09-23 Jingbo Liu Method and Apparatus for Estimating Rotor Position in a Sensorless Synchronous Motor

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105827168A (en) * 2016-05-10 2016-08-03 华中科技大学 PMSM control method and system based on sliding mode observation
WO2018077593A1 (en) * 2016-10-27 2018-05-03 Siemens Aktiengesellschaft Method for determining a deadzone angle of a backlash in a mechanical drive-train system, method for controlling a drive motor controller as well as drive-train system
CN110557070A (en) * 2019-09-30 2019-12-10 山东深川变频科技股份有限公司 permanent magnet synchronous motor parameter identification method based on second-order sliding-mode observer

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
基于扩张状态观测器的永磁电机电流预测控制;张明晖;杨家强;陈磊;楼佳羽;;浙江大学学报(工学版)(第07期);全文 *
永磁同步电机无位置传感器双滑模鲁棒控制;张细政;王耀南;杨民生;;电机与控制学报(第06期);全文 *
辨识转动惯量扰动观测器的PMSM滑模控制;侯利民;徐越;何佩宇;阎馨;;电机与控制学报(第09期);全文 *

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