CN109951121A - Permanent magnet synchronous motor position Sensorless Control based on non-singular terminal sliding formwork - Google Patents
Permanent magnet synchronous motor position Sensorless Control based on non-singular terminal sliding formwork Download PDFInfo
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- CN109951121A CN109951121A CN201910283776.1A CN201910283776A CN109951121A CN 109951121 A CN109951121 A CN 109951121A CN 201910283776 A CN201910283776 A CN 201910283776A CN 109951121 A CN109951121 A CN 109951121A
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Abstract
The present invention relates to a kind of permanent magnet synchronous motor position Sensorless Controls based on non-singular terminal sliding formwork, belong to motor control technology field.Specific step is as follows: the design nonsingular fast terminal sliding-mode surface of one integral form first.Then, the mathematical model according to durface mounted permanent magnet synchronous motor under two-phase stationary coordinate system designs sliding mode observer and combines the control law of quick power Reaching Law design terminal sliding mode observer.Finally, carrying out stability analysis to designed observer.The present invention can effectively improve permanent-magnet synchronous motor rotor position and speed estimate precision, and design and be simply easy to Project Realization, application value with higher.
Description
Technical field
The present invention relates to motor control technology field, specifically a kind of permanent magnet synchronous motor based on non-singular terminal sliding formwork
The method of position Sensorless Control.
Background technique
Permasyn morot has simple structure, reliable for operation, small in size, light weight, loss small, high-efficient, and
The shape and size of motor can be with equal remarkable advantages versatile and flexible.In recent years, with the progress of permanent magnetic material performance and permanent magnetism
Electric machines control technology it is perfect, permanent magnet synchronous motor is in production and living every field extensive application.But permanent magnet synchronous electric
Machine is multivariable, close coupling, non-linear and variable element complex object, in actually control, in order to obtain excellent controlling
Can, need to obtain the revolving speed and rotor position information of permanent magnet synchronous motor in real time.Using photoelectric encoder, rotary transformer etc.
Mechanical pick-up device obtains real-time revolving speed and rotor position information, system cost can be made to increase, and volume mass becomes larger, and runs ring
Border is severely limited.Therefore, it is necessary to using all kinds of control algolithms realize to permanent magnet synchronous electric dynamoelectric signal it is real-time acquire come
Rotor-position signal and tach signal are extracted, replaces the mechanical pick-up device to obtain real-time revolving speed rotor position information with this, it is real
The sensorless strategy of existing permanent magnet synchronous motor.
At present, it has been suggested that the method for permanent magnet synchronous motor position Sensorless Control mainly have: model reference is adaptive
Ying Fa, sliding mode observer method, neural network etc..Sliding mode observer method is a kind of based on to the mistake between constant current and feedback current
Difference, and the counter electromotive force of motor, estimation spinner velocity are reconstructed by the error, key is the selection and cunning of sliding-mode surface function
The selection of mould gain should guarantee convergence rate, also to avoid gain excessive and cause to generate excessive buffeting when motor operation
Problem.Terminal sliding mode observer is being applied in the research of permanent magnet synchronous motor position Sensorless Control, most methods
Be mainly based upon the research of traditional non-singular terminal sliding-mode surface, and improved on this basis, although achieve it is some into
Exhibition, but the above method all employs Second Order Sliding Mode Control, and introducing differential term keeps design complicated；Either by terminal sliding mode method
New composite control method is formed in conjunction with other methods, but these methods are while pursuing more superior observer performance
Keep algorithm more complicated.
Summary of the invention
The object of the present invention is to provide it is a kind of for permanent magnet synchronous motor without position vector control when rotor-position and turn
The low solution to the problem of fast estimated accuracy, proposes a kind of new model terminal sliding mode observer based on quick power Reaching Law.
The program not only efficiently solves the above problem, but also designs simple.
To achieve the above object, present invention employs following technical measures:
A kind of new model terminal sliding mode observer based on quick power Reaching Law, comprising the following steps:
Step 1, the design nonsingular fast terminal sliding-mode surface of one integral form.
Step 2, the mathematical model according to durface mounted permanent magnet synchronous motor under two-phase stationary coordinate system, design sliding formwork observation
Device
Step 3, in conjunction with the control law of quick power Reaching Law design terminal sliding mode observer.
Step 4 carries out stability analysis to designed observer.
The utility model has the advantages that
Compared with prior art, the present invention its advantages are embodied in:
The present invention devises the nonsingular fast terminal sliding-mode surface of integral form, and introducing differential term is not only avoided to simplify observation
The design of device also optimizes the performance of observer；And quick power Reaching Law is combined, realize the fast convergence of observer and accurate
Tracking effectively inhibits sliding formwork control to buffet problem；Finally the stability of observer is demonstrated with liapunov function.This hair
The bright rotor-position and speed estimate precision for not only effectively improving permanent magnet synchronous motor without position vector control when, Er Qieshe
Meter is simple, is convenient for Project Realization.
Detailed description of the invention
Attached drawing is used to provide further understanding of the present invention, and constitutes part of specification, with reality of the invention
It applies example to be used to explain the present invention together, not be construed as limiting the invention.In the accompanying drawings:
Fig. 1 is the structure chart of the new model terminal sliding mode observer based on quick power Reaching Law of the application
Fig. 2 is traditional nonsingular fast terminal sliding mode observer structure chart；
Fig. 3 is the permanent magnet synchronous motor position Sensorless Control analogous diagram based on non-singular terminal sliding formwork of the application；
Fig. 4 is error for rotating speed estimation simulation result diagram of traditional sliding mode observer in speed change.
Fig. 5 is the simulation result diagram of traditional sliding mode observer rotor position estimate error in speed change.
Fig. 6 is the simulation result diagram of traditional sliding mode observer error for rotating speed estimation in variable load.
Fig. 7 is the simulation result diagram of traditional sliding mode observer rotor position estimate error in variable load.
Fig. 8 is the simulation result diagram of the sliding mode observer of the invention rotor position estimate error in variable load.
Fig. 9 is the simulation result diagram of the sliding mode observer of the invention rotor position estimate error in variable load.
Figure 10 is the simulation result diagram of the sliding mode observer of the invention rotor position estimate error in variable load.
Figure 11 is the simulation result diagram of the sliding mode observer of the invention rotor position estimate error in variable load.
Specific embodiment
Specific embodiment 1: present embodiment is illustrated referring to Fig.1, based on nonsingular end described in present embodiment
The method for holding the permanent magnet synchronous motor position Sensorless Control of sliding formwork, the described method comprises the following steps:
Step 1, the design nonsingular fast terminal sliding-mode surface of one integral form.
Step 2, the mathematical model according to durface mounted permanent magnet synchronous motor under two-phase stationary coordinate system, design sliding formwork observation
Device
Step 3, in conjunction with the control law of quick power Reaching Law design terminal sliding mode observer.
Step 4 carries out stability analysis to designed observer.
In present embodiment, the application proposes a kind of new model terminal Design of Sliding Mode Observer based on quick power Reaching Law
Method effectively improves permanent magnet synchronous electric by designing the novel nonsingular fast terminal sliding-mode surface of integral form and control law
Rotor-position and speed estimate precision when machine is controlled without position vector.
Specific embodiment 2: present embodiment be to described in specific embodiment one based on non-singular terminal sliding formwork
Permanent magnet synchronous motor position Sensorless Control is described further, and in present embodiment, integral form described in step 1 is non-
Unusual fast terminal sliding-mode surface are as follows:
In formula: b, c, r > 0；x1For the state variable of system.
Specific embodiment 3: present embodiment be to described in specific embodiment one based on non-singular terminal sliding formwork
Permanent magnet synchronous motor position Sensorless Control is described further, and in present embodiment, step 2 is specifically in accordance with the following methods
Implement:
It is as follows based on the current status equation under rest frame to establish durface mounted permanent magnet synchronous motor:
In formula,iα、iβFor stator current；uα、uβFor stator voltage；Eα、EβIt is anti-electronic to extend
Gesture.
Sliding mode observer equation is constructed according to mathematical model of the durface mounted permanent magnet synchronous motor under two-phase stationary coordinate system
It is as follows:
In formula,For the observation of stator current；uα、uβIt is inputted for the control of observer.
Specific embodiment 4: present embodiment be to described in specific embodiment three based on non-singular terminal sliding formwork
Permanent magnet synchronous motor position Sensorless Control is described further, and in present embodiment, step 3 is specifically in accordance with the following methods
Implement:
According to sliding mode observer equation, electric current observation error is enabledBecome for the state of system
Amount.
According to the nonsingular fast terminal sliding-mode surface equation of integral form, enableAnd introduce quick power approach
Rule, can obtain the control law of sliding mode observer are as follows:
In formula, k, ε>0,0<α<1, β>=1.
Specific embodiment 5: present embodiment be to described in specific embodiment two based on non-singular terminal sliding formwork
Permanent magnet synchronous motor position Sensorless Control is described further, in present embodiment, step 4 specifically:
Choose liapunov function:
To V derivation, obtain:
| s |≤min ((| e |/k)1/α,|e|/ε|x1|β) within,It is negative definite, i.e., the system is stable.
As s > 0, thenTo the error side of the stator current after substitution derivation after sliding mode observer control law derivation
Journey can obtain:
WhenWhen,I.e.Quickly reduce.
Similarly, as s < 0,I.e.Quickly increase
Greatly, then whenWhen, s=0 is realized in finite time.
Therefore the observer is stable.
Simulation analysis:
Simulation model is built under MATLAB/Simulink environment, using id=0 vector control strategy, such as Fig. 3 institute
Show.
Wherein, the parameter of electric machine in emulation are as follows:
PN=3kW, UN=200V, IN=18A, nN=3000r/min, number of pole-pairs pn=5, stator inductance Ls=0.827mH,
Stator resistance R=0.258 Ω, magnetic linkage ψf=0.057Wb, rotary inertia J=0.006 (kgm2), damped coefficient B=0；
Simulated conditions setting are as follows:
PWM switching frequency is set as fpwm=10kHz selects fixed step size ode3 algorithm, and simulation step length is set as 2 × 10- 7s。
The parameter of terminal sliding mode observer of the present invention are as follows:
A=1；Gama=1；Alfa=0.5；Beta=1.5；B=100；C=100；K=25；ε=15；
(1) speed change is tested: the initial given rotating speed of system is Nref=500r/min, band 3Nm constant load torque are run.?
0.25s moment given rotating speed sports Nref=1000r/min, simulation time 0.5s.
(2) variable load is tested: system given rotating speed is maintained at Nref=500r/min, detent torque 3Nm, in 0.2s
Load becomes 7Nm, and load becomes 5Nm, simulation time 0.5s when 0.35s.
Simulation result is as shown in Fig. 4~Figure 11.
It can be seen that from Fig. 4 and Fig. 8 in rotational speed setup NrefWhen=500r/min, Type New Observer designed by this paper exists
Error for rotating speed estimation is up to 0.05r/min when stable operation, and traditional observer error for rotating speed estimation in stable operation
It is up to 0.24r/min, in comparison, rotational speed setup becomes after speed estimate precision of the present invention improves 79.2%, 0.25s
Nref=1000r/min, the error for rotating speed estimation in stable operation of the observer designed by the present invention is up to 0.08r/ at this time
Min, and traditional observer error for rotating speed estimation in stable operation is up to 0.26r/min, in comparison, of the invention turns
Fast precision improves 69.2%, it can be seen that, observer designed by the present invention in rotation speed change there is higher revolving speed to estimate
Count precision.From the comparison of two figure of Fig. 5 and Fig. 9 as can be seen that in rotational speed setup NrefWhen=500r/min, designed by this paper
Observer is up to 0.047rad in non-toggle moment rotor position estimate error, and traditional observer turns at the non-toggle moment
Sub- position estimation error is up to 0.095rad, and rotor position estimate precision of the invention improves revolving speed after 50.5%, 0.25s
It is given to become Nref=1000r/min, observer designed by the present invention is maximum in non-toggle moment rotor position estimate error at this time
For 0.060rad, and traditional observer is up to 0.103rad in non-toggle moment rotor position estimate error, in comparison,
Rotor position estimate precision improves 41.7%, it can be seen that, observer designed by the present invention has more in rotation speed change
High rotor position estimate precision, and rotor position estimate fluctuating error is smaller.Comparing from Fig. 6 and Figure 10 can be seen that
When load torque is given as 3Nm, 7Nm, 5Nm, the speed estimate in stable operation of Type New Observer designed by this paper
Error is up to 0.06r/min, and traditional observer error for rotating speed estimation in stable operation is up to 0.24r/min, phase
Compared under, speed estimate precision of the invention improves 75%, it can be seen that, observer designed by the present invention is in load torque
There is higher speed estimate precision when variation.From Fig. 7 and Figure 11 compare as can be seen that load torque be given as 3Nm,
When 7Nm, 5Nm, Type New Observer designed by the present invention is up in non-toggle moment rotor position estimate error
0.047rad, and traditional observer is up to 0.095rad in non-toggle moment rotor position estimate error, in comparison, this
The rotor position estimate precision of invention improves 50.5%, it can be seen that, observer designed by the present invention becomes in load torque
There is higher rotor position estimate precision, and rotor position estimate fluctuating error is smaller when change.
Claims (5)
1. a kind of permanent magnet synchronous motor position Sensorless Control based on non-singular terminal sliding formwork, it is characterised in that: specifically press
Implement according to following steps:
Step 1, the design nonsingular fast terminal sliding-mode surface of one integral form
Step 2, the mathematical model according to durface mounted permanent magnet synchronous motor under two-phase stationary coordinate system design sliding mode observer
Step 3, in conjunction with the control law of quick power Reaching Law design terminal sliding mode observer
Step 4 carries out stability analysis to designed observer.
2. a kind of permanent magnet synchronous motor position-sensor-free control based on non-singular terminal sliding formwork according to claim 1
System, it is characterised in that: the nonsingular fast terminal sliding-mode surface of integral form described in step 1 are as follows:
In formula: b, c, r > 0；x1For the state variable of system.
3. a kind of permanent magnet synchronous motor position-sensor-free control based on non-singular terminal sliding formwork according to claim 1
System, it is characterised in that: the step 2 is specifically implemented according to the following steps:
Step 2.1, to establish durface mounted permanent magnet synchronous motor as follows based on the current status equation under rest frame:
In formula,iα、iβFor stator current；uα、uβFor stator voltage；Eα、EβTo extend counter electromotive force；
Step 2.2 constructs sliding mode observer according to mathematical model of the durface mounted permanent magnet synchronous motor under two-phase stationary coordinate system
Equation is as follows:
In formula,For the observation of stator current；uα、uβIt is inputted for the control of observer.
4. a kind of permanent magnet synchronous motor position-sensor-free control based on non-singular terminal sliding formwork according to claim 3
System, it is characterised in that: the step 3 is specifically implemented according to the following steps:
Step 3.1, according to sliding mode observer equation, enable electric current observation errorFor the shape of system
State variable；
Step 3.2, according to the nonsingular fast terminal sliding-mode surface equation of integral form, enableAnd introduce quick power
Reaching Law can obtain the control law of sliding mode observer are as follows:
In formula, k, ε>0,0<α<1, β>=1.
5. a kind of permanent magnet synchronous motor position-sensor-free control based on non-singular terminal sliding formwork according to claim 2
System, it is characterised in that: the step 4 specifically:
Step 4.1 chooses liapunov function:
To V derivation, obtain:
| s |≤min ((| e |/k)1/α,|e|/ε|x1|β) within,It is negative definite, i.e., the system is stable；
As s > 0, thenIt, can to the error equation of the stator current after substitution derivation after sliding mode observer control law derivation
:
WhenWhen,I.e.Quickly reduce；
Similarly, as s < 0,I.e.Quickly increase, then
WhenWhen, s=0 is realized in finite time；
Therefore the observer is stable.
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| CN114598207A (en) * | 2022-03-21 | 2022-06-07 | 安徽理工大学 | Sliding mode variable structure control method based on logarithmic approach rate |
| CN114844418A (en) * | 2022-04-18 | 2022-08-02 | 西南交通大学 | Speed sensorless control method for induction motor |
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| CN114244214B (en) * | 2021-11-05 | 2023-10-24 | 安徽工程大学 | Position control algorithm of permanent magnet synchronous motor based on improved sliding mode control |
| CN114598207A (en) * | 2022-03-21 | 2022-06-07 | 安徽理工大学 | Sliding mode variable structure control method based on logarithmic approach rate |
| CN114844418A (en) * | 2022-04-18 | 2022-08-02 | 西南交通大学 | Speed sensorless control method for induction motor |
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