Permanent magnet synchronous motor rotating speed disturbance suppression method based on switch state observer

Abstract

The invention discloses a permanent magnet synchronous motor rotating speed disturbance suppression method based on a switch state observer, and belongs to the field of rotating speed control of permanent magnet synchronous motors. The method comprises the following steps: S1, establishing a mechanical motion model and a stator voltage model of the permanent magnet synchronous motor; s2, constructing a switch expansion state observer based on the mechanical motion model; s3, selecting parameters and switching points of the switch expansion state observer; s4, based on the quasi-proportional resonance controller model, combining a control instruction in a rotating speed control system and a state quantity of a switch expansion state observer, and taking a reference rotating speed instruction in the rotating speed control system, and a permanent magnet synchronous motor rotating speed observation value and a rotating speed total disturbance observation value which are obtained through observation of the switch expansion state observer as input; constructing a quasi-proportional resonance active-disturbance-rejection control law by taking the reference electromagnetic torque instruction as output; and S5, based on the stator voltage model, constructing a proportional-integral current controller. The method is used for active-disturbance-rejection rotating speed disturbance suppression of the permanent magnet synchronous motor.

Description

Technical Field

[0001] The invention belongs to the field of speed control of permanent magnet synchronous motors, and in particular relates to a method for suppressing speed disturbance of permanent magnet synchronous motors based on a switch state observer. Background Art

[0002] Permanent magnet synchronous motors have been widely used in high-precision servo systems, which place high demands on the speed control accuracy of permanent magnet synchronous motors. Suppressing disturbances in permanent magnet synchronous motor systems is the key to high-precision speed control of permanent magnet synchronous motors. The active disturbance rejection control method is the basic method for suppressing speed disturbances of permanent magnet synchronous motors. The active disturbance rejection control method includes two parts: the active disturbance rejection control law and the extended state observer. However, the existing active disturbance rejection control methods often focus on the observation and suppression of load torque disturbances, and lack the ability to suppress speed disturbances caused by current sampling errors and speed measurement noise. In addition, the existing active disturbance rejection control methods often focus on the observation and suppression of speed disturbances by the extended state observer, and the active disturbance rejection control law only plays the role of providing reference current signal output. Therefore, the existing permanent magnet synchronous motor speed disturbance suppression scheme lacks the versatility to suppress various types of speed disturbances, and fails to make the active disturbance rejection control law and the extended state observer play the role of suppressing speed measurement noise. High-precision servo motors are a widely used permanent magnet synchronous motor. If there is no effective speed disturbance suppression method, its application in industrial robots, CNC machine tools and other fields will be limited. Summary of the invention

[0003] The purpose of the present invention is to solve the problem of insufficient speed disturbance suppression capability caused by current sampling error and speed measurement noise when a permanent magnet synchronous motor performs high-precision speed control, and further provide a permanent magnet synchronous motor speed disturbance suppression method based on a switch state observer.

[0004] The speed disturbance is the factor that causes the motor speed to change.

[0005] The invention discloses a quasi-resonant self-disturbance-rejection permanent magnet synchronous motor speed disturbance suppression scheme based on a switch extended state observer, which can effectively suppress various speed disturbances and has good application prospects in the fields of industrial robots, CNC machine tools, etc.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer comprises the following steps:

[0008] S1. Based on space vector transformation, the mechanical motion model and stator voltage model of the permanent magnet synchronous motor in the dq subspace are established;

[0009] S2. Based on the mechanical motion model of the permanent magnet synchronous motor established in step S1, combined with the control command in the speed control system, the speed measurement value of the permanent magnet synchronous motor in the speed control system, the reference speed command, and the reference electromagnetic torque command are used as observer inputs, and the mechanical speed and the total speed disturbance are used as observer state quantities to construct a switch expansion state observer;

[0010] S3. Select the parameters and switching points of the switch expansion state observer according to the transfer function of the rated torque and speed disturbance of the permanent magnet synchronous motor to the speed;

[0011] S4. Based on the quasi-proportional resonant controller model, in combination with the control command in the speed control system and the state quantity of the switch extended state observer, the reference speed command in the speed control system, and the permanent magnet synchronous motor speed observation value and the total speed disturbance observation value obtained by the switch extended state observer in step S3 are used as inputs, and the reference electromagnetic torque command is used as output to construct a quasi-proportional resonant auto-disturbance rejection control law;

[0012] S5. Based on the stator voltage model of the permanent magnet synchronous motor established in step S1, a proportional-integral current controller is constructed with the reference electromagnetic torque command provided by the quasi-proportional resonant self-disturbance rejection control law constructed in step S4 as input.

[0013] Furthermore, in step S1, based on the space vector transformation, the mechanical motion model and stator voltage model of the permanent magnet synchronous motor in the dq subspace are established, which are respectively:

[0014]

[0015] In the formula, i d 、i q are d-axis current and q-axis current respectively; L d , L q are d-axis inductance and q-axis inductance respectively; T e , T L They are electromagnetic torque and load torque respectively; ω m ,ω m0 are the mechanical speed and the mechanical speed measurement respectively; is the random measurement noise; J is the rotor moment of inertia; B is the rotor viscous friction coefficient; p n is the number of rotor pole pairs; ψ f is the rotor permanent magnet flux;

[0016]

[0017] In the formula, u d 、u q are d-axis voltage and q-axis voltage respectively; R s is the stator phase resistance; ωe is the electromagnetic speed.

[0018] Furthermore, in step S2, the mechanical motion model of the permanent magnet synchronous motor established in step S1 is combined with the control command in the speed control system, the reference speed command and the reference electromagnetic torque command in the speed control system are used as observer inputs, and the mechanical speed and the total speed disturbance are used as observer state quantities to construct a switch expansion state observer;

[0019]

[0020] In the formula, They are the mechanical speed observation value and the speed total disturbance observation value respectively; is the nominal value of the control gain; J0 is the nominal value of the rotor moment of inertia; is the reference electromagnetic torque command; l1 and k2 are the observer gain coefficients; x e is the state quantity of the speed control error, and its expression is:

[0021]

[0022] In the formula, is the reference mechanical speed command; ω c is the cut-off frequency of the low-pass filter; δ is the switching point of the switch expansion state observer.

[0023] Furthermore, in step S3, the parameters and switching points of the switch extended state observer are selected according to the transfer function of the rated torque and speed disturbance of the permanent magnet synchronous motor to the speed; specifically:

[0024] l1, k2, ω c are the coefficients of the switch extended state observer, l1, ω c The value range of and k2 is:

[0025]

[0026] In the formula, ω o is the observer bandwidth;

[0027] After the coefficients of the switch extended state observer are determined, the transfer function G of the speed disturbance to the speed is d (s), combined with the rated load torque, calculate the maximum value Δω of the mechanical speed change caused by the load torque m max ;

[0028]

[0029] In the formula, is the control quantity gain; k pis the proportional gain of the ADRC law; s is the Laplace operator;

[0030] According to the maximum value Δω of the mechanical speed change mmax Select the switching point δ;

[0031] 0.1Δω mmax <δ<0.25Δω mmax .

[0032] Furthermore, in step S4, based on the quasi-proportional resonant controller model, the control command in the speed control system and the state quantity of the switch extended state observer are combined, the reference speed command in the speed control system, and the permanent magnet synchronous motor speed observation value and the speed total disturbance observation value obtained by the switch extended state observer in step S3 are used as inputs, and the reference electromagnetic torque command is used as output to construct a quasi-proportional resonant auto-disturbance rejection control law;

[0033]

[0034] In the formula, k r1 , k r2 is the resonance gain; ω c1 ,ω c2 is the shear frequency; ω e is the electromagnetic speed; G QPRC (s) is the transfer function of the quasi-proportional resonant controller.

[0035] Furthermore, in step S5, the stator voltage model of the permanent magnet synchronous motor established in step S1 is used as input to construct a proportional-integral current controller using the reference electromagnetic torque command provided by the quasi-proportional resonant anti-disturbance control law constructed in step S4;

[0036]

[0037] In the formula, They are the d-axis and q-axis reference voltage instructions respectively; are the reference current instructions for the d-axis and q-axis respectively; k pd , k pq are the proportional coefficients of the d-axis and q-axis current controllers respectively; k id , k iq They are the integral coefficients of the d-axis and q-axis current controllers respectively.

[0038] The beneficial effects of the present invention relative to the prior art are as follows: the switch extended state observer with speed measurement noise suppression function constructed by the present invention combines the noise suppressing low-pass filter and the switch switching mechanism of the extended state observer, and compared with the traditional extended state observer, the ability of the extended state observer to suppress speed measurement noise and the observation speed of the total speed disturbance are enhanced. In addition, the present invention also adopts an auto-disturbance rejection control law based on a quasi-proportional resonant controller model, which enhances the ability of the auto-disturbance rejection control law to suppress speed disturbances caused by current sampling errors. The auto-disturbance rejection control law and the auto-disturbance rejection high-precision speed control system constructed by the auto-disturbance rejection control law and the adopted switch extended state observer can effectively suppress various speed disturbances of the permanent magnet synchronous motor, and has a high-precision and stable speed control effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the permanent magnet synchronous motor speed disturbance suppression method based on the switch state observer of the present invention. DETAILED DESCRIPTION

[0040] This embodiment discloses a method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer, the method comprising the following steps:

[0041] S1. Based on space vector transformation, the mechanical motion model and stator voltage model of the permanent magnet synchronous motor in the dq subspace are established;

[0042] S2. Based on the mechanical motion model of the permanent magnet synchronous motor established in step S1, combined with the control command in the speed control system, the speed measurement value of the permanent magnet synchronous motor in the speed control system, the reference speed command, and the reference electromagnetic torque command are used as observer inputs, and the mechanical speed and the total speed disturbance are used as observer state quantities to construct a switch expansion state observer;

[0043] S3. Select the parameters and switching points of the switch expansion state observer according to the transfer function of the rated torque and speed disturbance of the permanent magnet synchronous motor to the speed;

[0044] S4. Based on the quasi-proportional resonant controller model (a known model), combined with the control command in the speed control system (the prior art) and the state quantity of the switch extended state observer, the reference speed command in the speed control system, and the permanent magnet synchronous motor speed observation value and the speed total disturbance observation value obtained by the switch extended state observer in step S3 are used as inputs, and the reference electromagnetic torque command is used as output to construct a quasi-proportional resonant auto-disturbance rejection control law;

[0045] S5. Based on the stator voltage model of the permanent magnet synchronous motor established in step S1, a proportional-integral current controller is constructed with the reference electromagnetic torque command provided by the quasi-proportional resonant self-disturbance rejection control law constructed in step S4 as input.

[0046] Furthermore, in step S1, based on the space vector transformation, the mechanical motion model and stator voltage model of the permanent magnet synchronous motor in the dq subspace are established, which are respectively:

[0047]

[0048] In the formula, i d 、i q are d-axis current and q-axis current respectively; L d , L q are d-axis inductance and q-axis inductance respectively; T e , T L They are electromagnetic torque and load torque respectively; ω m ,ω m0 are the mechanical speed and the mechanical speed measurement respectively; is the random measurement noise; J is the rotor moment of inertia; B is the rotor viscous friction coefficient; p n is the number of rotor pole pairs; ψ f is the rotor permanent magnet flux;

[0049]

[0050] In the formula, u d 、u q are d-axis voltage and q-axis voltage respectively; R s is the stator phase resistance; ω e is the electromagnetic speed.

[0051] Furthermore, in step S2, the mechanical motion model of the permanent magnet synchronous motor established in step S1 is combined with the control command in the speed control system, the reference speed command and the reference electromagnetic torque command in the speed control system are used as observer inputs, and the mechanical speed and the total speed disturbance are used as observer state quantities to construct a switch expansion state observer;

[0052]

[0053] In the formula, They are the mechanical speed observation value and the speed total disturbance observation value respectively; is the nominal value of the control gain; J0 is the nominal value of the rotor moment of inertia; is the reference electromagnetic torque command; l1 and k2 are the observer gain coefficients; x e is the state quantity of the speed control error, and its expression is:

[0054]

[0055] In the formula, is the reference mechanical speed command; ωc is the cut-off frequency of the low-pass filter; δ is the switching point of the switch expansion state observer.

[0056] Furthermore, in step S3, the parameters and switching points of the switch extended state observer are selected according to the transfer function of the rated torque and speed disturbance of the permanent magnet synchronous motor to the speed; specifically:

[0057] l1, k2, ω c are the coefficients of the switch extended state observer, l1, ω c The value range of and k2 is:

[0058]

[0059] In the formula, ω o is the observer bandwidth;

[0060] After the coefficients of the switch extended state observer are determined, the transfer function G of the speed disturbance to the speed is d (s), combined with the rated load torque, calculate the maximum value Δω of the mechanical speed change caused by the load torque m max ;

[0061]

[0062] In the formula, is the control quantity gain; k p is the proportional gain of the ADRC law; s is the Laplace operator;

[0063] According to the maximum value Δω of the mechanical speed change mmax Select the switching point δ;

[0064] 0.1Δω mmax <δ<0.25Δω mmax .

[0065] Furthermore, in step S4, based on the quasi-proportional resonant controller model, the control command in the speed control system and the state quantity of the switch extended state observer are combined, the reference speed command in the speed control system, and the permanent magnet synchronous motor speed observation value and the speed total disturbance observation value obtained by the switch extended state observer in step S3 are used as inputs, and the reference electromagnetic torque command is used as output to construct a quasi-proportional resonant auto-disturbance rejection control law;

[0066]

[0067] In the formula, k r1 , k r2 is the resonance gain; ω c1 ,ω c2 is the shear frequency; ω eis the electromagnetic speed; G QPRC (s) is the transfer function of the quasi-proportional resonant controller.

[0068] Furthermore, in step S5, the stator voltage model of the permanent magnet synchronous motor established in step S1 is used as input to construct a proportional-integral current controller using the reference electromagnetic torque command provided by the quasi-proportional resonant anti-disturbance control law constructed in step S4;

[0069]

[0070] In the formula, They are the d-axis and q-axis reference voltage instructions respectively; are the reference current instructions for the d-axis and q-axis respectively; k pd , k pq are the proportional coefficients of the d-axis and q-axis current controllers respectively; k id , k iq They are the integral coefficients of the d-axis and q-axis current controllers respectively.

[0071] The working principle is: Figure 1 As shown, after the speed reference signal is given, the reference torque signal is calculated by the quasi-proportional resonant anti-disturbance control law in combination with the mechanical speed observation value and the total speed disturbance observation value provided by the switch expansion state observer (obtained by the quasi-proportional resonant anti-disturbance control law calculation formula in step S4). After the reference torque signal and the d and q axis currents are subtracted, the PI current controller calculates the d and q axis reference voltage signals (obtained by the proportional integral current controller calculation formula in step S5), which are provided to the inverter to drive the motor to rotate. The motor three-phase current and rotor position signals are sampled and returned to the controller.

[0072] The above are only preferred specific implementation modes of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer, characterized in that: The method comprises the following steps: S1. Based on space vector transformation, the mechanical motion model and stator voltage model of the permanent magnet synchronous motor in the dq subspace are established; S2. Based on the mechanical motion model of the permanent magnet synchronous motor established in step S1, combined with the control command in the speed control system, the speed measurement value of the permanent magnet synchronous motor in the speed control system, the reference speed command, and the reference electromagnetic torque command are used as observer inputs, and the mechanical speed and the total speed disturbance are used as observer state quantities to construct a switch expansion state observer; S3. Select the parameters and switching points of the switch expansion state observer according to the transfer function of the rated torque and speed disturbance of the permanent magnet synchronous motor to the speed; S4. Based on the quasi-proportional resonant controller model, in combination with the control command in the speed control system and the state quantity of the switch extended state observer, the reference speed command in the speed control system, and the permanent magnet synchronous motor speed observation value and the total speed disturbance observation value obtained by the switch extended state observer in step S3 are used as inputs, and the reference electromagnetic torque command is used as output to construct a quasi-proportional resonant auto-disturbance rejection control law; S5. Based on the stator voltage model of the permanent magnet synchronous motor established in step S1, a proportional-integral current controller is constructed with the reference electromagnetic torque command provided by the quasi-proportional resonant self-disturbance rejection control law constructed in step S4 as input.

2. The method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer according to claim 1 is characterized in that: In step S1, based on the space vector transformation, the mechanical motion model and stator voltage model of the permanent magnet synchronous motor in the dq subspace are established, which are respectively: In the formula, i d 、i q are d-axis current and q-axis current respectively; L d , L q are d-axis inductance and q-axis inductance respectively; T e , T L They are electromagnetic torque and load torque respectively; ω m ,ω m0 are the mechanical speed and the mechanical speed measurement respectively; is the random measurement noise; J is the rotor moment of inertia; B is the rotor viscous friction coefficient; p n is the number of rotor pole pairs; ψ f is the rotor permanent magnet flux; In the formula, u d 、u q are d-axis voltage and q-axis voltage respectively; R s is the stator phase resistance; ω e is the electromagnetic speed.

3. The method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer according to claim 2 is characterized in that: In step S2, the mechanical motion model of the permanent magnet synchronous motor established in step S1 is combined with the control command in the speed control system, the reference speed command and the reference electromagnetic torque command in the speed control system are used as observer inputs, and the mechanical speed and the total speed disturbance are used as observer state quantities to construct a switch expansion state observer; In the formula, They are the mechanical speed observation value and the speed total disturbance observation value respectively; is the nominal value of the control gain; J0 is the nominal value of the rotor moment of inertia; is the reference electromagnetic torque command; l1 and k2 are the observer gain coefficients; x e is the state quantity of the speed control error, and its expression is: In the formula, is the reference mechanical speed command; ω c is the cut-off frequency of the low-pass filter; δ is the switching point of the switch expansion state observer.

4. The method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer according to claim 3 is characterized in that: In step S3, the parameters and switching points of the switch extended state observer are selected according to the transfer function of the rated torque and speed disturbance of the permanent magnet synchronous motor to the speed; specifically: l1, k2, ω c are the coefficients of the switch extended state observer, l1, ω c The value range of and k2 is: In the formula, ω o is the observer bandwidth; After the coefficients of the switch extended state observer are determined, the transfer function G of the speed disturbance to the speed is d (s), combined with the rated load torque, calculate the maximum value Δω of the mechanical speed change caused by the load torque mmax ; In the formula, is the control quantity gain; k p is the proportional gain of the ADRC law; s is the Laplace operator; According to the maximum value Δω of the mechanical speed change mmax Select the switching point δ; 0.1D mmax <δ<0.25δ mmax 。 5. The method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer according to claim 4 is characterized in that: In step S4, based on the quasi-proportional resonant controller model, the control command in the speed control system and the state quantity of the switch extended state observer are combined, the reference speed command in the speed control system, and the permanent magnet synchronous motor speed observation value and the speed total disturbance observation value obtained by the switch extended state observer in step S3 are used as inputs, and the reference electromagnetic torque command is used as output to construct a quasi-proportional resonant auto-disturbance rejection control law; In the formula, k r1 , k r2 is the resonance gain; ω c1 ,ω c2 is the shear frequency; ω e is the electromagnetic speed; G QPRC (s) is the transfer function of the quasi-proportional resonant controller.

6. The method for suppressing speed disturbance of a permanent magnet synchronous motor based on a switch state observer according to claim 5 is characterized in that: In step S5, the stator voltage model of the permanent magnet synchronous motor established in step S1 is used as input to construct a proportional-integral current controller by taking the reference electromagnetic torque command provided by the quasi-proportional resonant auto-disturbance rejection control law constructed in step S4 as input; In the formula, They are the d-axis and q-axis reference voltage instructions respectively; are the reference current instructions for the d-axis and q-axis respectively; k pd , k pq are the proportional coefficients of the d-axis and q-axis current controllers respectively; k id , k iq They are the integral coefficients of the d-axis and q-axis current controllers respectively.

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