CN106487300A - A kind of AC servo motor controlled based on magnetic linkage angle - Google Patents

Abstract

The present invention relates to a kind of permanent magnet synchronous servo motor control method, by using the angled relationships between stator and rotor flux, determines the input of SVPWM unit, and then realizes the control to permanent magnet synchronous servo motor.By detecting the three-phase current of inverter output, it is considered to which coordinate transform under dq coordinate system and control law are calculated the electromagnetic torque of permanent magnet synchronous servo motor.By Voltage-Current model it is estimated that the amplitude of stator magnetic linkage.As the angle of change stator, rotor flux can realize direct torque, i.e., torque error is compensated by controlling angle error.Speeds control then adopts nonlinear control method, and velocity error then exports the reference value of electromagnetic torque after speed regulator, by comparing, with the torque value for calculating, the controlled quentity controlled variable for obtaining angle afterwards.Again voltage control instructions are obtained by voltage equation, the action time of the voltage vector of selection is calculated using SVPWM, and then by the switch controlling signal of output inverter, realizes the direct torque to permanent magnet synchronous servo motor.

Description

A kind of AC servo motor controlled based on magnetic linkage angle

【Technical field】

The present invention relates to motor control technology field, more particularly to a kind of permanent magnet synchronous servo motor based on direct torque Control method.

【Background technology】

Permanent-magnet material very early by everybody cognition, in recent years, rare earth permanent-magnetic material because its higher residual flux density, rectify Stupid power and high energy product and be applied in the design of synchronous motor.There is no excitation dress in permagnetic synchronous motor (PMSM) itself Put, just without excitation loss, its mechanical property is harder, and disturbance rejection effect is good, this causes its security, stability and power close Degree etc. is greatly improved.Meanwhile, in speed regulating control, permagnetic synchronous motor has larger speed adjustable range and higher power Factor.Based on above advantage, permagnetic synchronous motor can meet the higher servo-drive control of runnability and technical indicator demand System processed.

At present, the more popular control method of permanent magnet synchronous servo motor is the vector control using speed and current double closed-loop System, substantially using traditional PI controller, PI control is simple with algorithm, and parameter adjustment is convenient, but PI controls this for speed ring It is a kind of linear control method in matter, and permanent magnet synchronous servo motor has the nonlinear characteristic of the change of parameter, this just makes Obtain PI control accuracy not high, it is impossible to desired performance indications when keeping designing, cannot also solve dynamic characteristic and stable state accuracy Between contradiction, its system robustness is poor.

Additionally, in prior art, servo-control system also includes direct torque mode.In direct torque mode, application More is that controller loads SVPWM, i.e. space vector pulse width modulation (Space Vector Pulse Width Modulation) algorithm, and traditional SVPWM algorithm is realized based on Orthogonal Decomposition voltage vector, which generally passes through The sector is located by voltage vector and action time solve, and need to carry out quadrature component complex calculation in calculating process, operation Time is longer, and control system operational efficiency is relatively low.

【Content of the invention】

In order to solve the problems, such as the control of existing permanent magnet synchronous servo motor, the invention provides a kind of be based on direct torque Permanent magnet synchronous servo motor control method.

Technical scheme is as follows：A kind of new permanent magnet synchronous servo motor control strategy is present invention employs, by determining Stator and the relation of rotor flux angle, determine the input of SVPWM unit, and then by controlling stator and rotor flux angle To realize the control to permanent magnet synchronous servo motor.By detecting the three-phase current of inverter output, it is considered under dq coordinate system Coordinate transform and control law are calculated the electromagnetic torque of permanent magnet synchronous servo motor.Can be evaluated whether by Voltage-Current model Go out the amplitude of stator magnetic linkage.As the angle δ of change stator, rotor flux can realize direct torque, i.e. by controlling Δ δ Compensation torque error Δ T_eSpeeds control then adopts nonlinear control method, and velocity error is then exported after speed regulator The reference value of electromagnetic torque, by comparing, with the torque value for calculating, the controlled quentity controlled variable for obtaining angle afterwards.Obtained by voltage equation again Voltage control instructions, calculate the action time of the voltage vector of selection using SVPWM, and then by the switch of output inverter Control signal, realizes the direct torque to permanent magnet synchronous servo motor.

Its derivation is as follows：

Clarke transformation for mula is：

Park is transformed to：

Shown in change between dq coordinate system and abc coordinate system such as formula (3)：

After being decoupled by coordinate transform, the Mathematical Modeling for obtaining permanent magnet synchronous servo motor in dq coordinate system is described as follows：

Voltage equation：

Flux linkage equations：

Electromagnetic torque equation：T_em=p_n(ψ_pmi_q-ψ_pmi_d)=p_n[ψ_pmi_q+(L_d-L_q)·i_di_q] (6)

Wherein：δ is stator, the angle of rotor flux, and Δ δ is variable angle amount, R_sFor stator resistance, u_d、i_dFor on d axle Component of voltage, current component；u_q、i_qFor the component of voltage on q axle, current component；ω_rAngular frequency is rotated for dq coordinate system； ψ_d、ψ_qFor magnetic linkage of the permanent magnet on dq axle；L is the equivalent armature inductance on dq coordinate system；ψ_sFor stator magnetic linkage, ψ_pmFor permanent magnetism The magnetic linkage that body is produced；p_nFor magnetic pole logarithm；

With magnetic linkage ψ under d axle_dAs a example by, it is assumed that t stator magnetic linkage is ψ_s(δ), through after a while, fixed to t+ Δ t Sub- magnetic linkage is changed into ψ_s(δ+Δ δ), if reference value isUnder d axle, magnetic linkage is ψ_d(δ+Δ δ), T_sFor switch periods.Then：

It is also possible to obtain with magnetic linkage ψ under q axle_q(δ+Δ δ), the above results are substituted in formula (4), you can realized The control of SVPWM input block.

Speeds control ring obtains the output of speed by the method for nonlinear Control, it is assumed that there are controlled quentity controlled variable V₁, then Its output difference is：

Wherein, J is rotary inertia, and B is coefficient of viscosity, T_LFor load torque,

Using first-order system configuration parameter V₁, i.e.,Wherein, K₁For control parameter undetermined,For Rotor velocity set-point；Then：

By governing speed parameter V₁, export i_qSet-point, final obtain torque reference value.

Beneficial effects of the present invention：A kind of new permanent magnet synchronous servo motor control strategy is present invention employs, is passed through Determine the relation of stator and rotor flux angle, determine the input of SVPWM unit, and then by controlling stator and rotor flux Angle is realizing the control to permanent magnet synchronous servo motor.Employ torque error Δ T is compensated by controlling Δ δ_eWith non-linear After control speed method, the response speed of motor control is improve, the Ability of Resisting Disturbance of system is enhanced, suppress trembling for speed Dynamic so as to be operated in complex environment.And solving needs to quadrature component in traditional SVPWM algorithm calculating process Complex calculation is carried out, run time is longer, the relatively low problem of control system operational efficiency.

【Description of the drawings】

Accompanying drawing described herein is used to provide a further understanding of the present invention, constitutes the part of the application, but Inappropriate limitation of the present invention is not constituted, in the accompanying drawings：

Fig. 1 is the flux linkage vector figure of the permanent magnet synchronous servo motor of the present invention

Fig. 2 is the voltage vector computing block diagram of the permanent magnet synchronous servo motor of the present invention

Fig. 3 is the torque simulation curve of the present invention

【Specific embodiment】

The present invention is described in detail below in conjunction with accompanying drawing and specific embodiment, illustrative examples therein and say Bright be only used for explaining the present invention, but be not intended as inappropriate limitation of the present invention.

It is three-phase static coordinate system referring to accompanying drawing 1, abc, α β is two-phase stator coordinate, dq is rotor coordinate, selectes α Direction of principal axis is consistent with motor stator a phase winding axis, and θ is the rotor space of rotor magnetic pole d axle relative stator a phase winding or α axle Position angle；δ is stator and rotor flux linkage vector angle.

Clarke transformation for mula is：

Park is transformed to：

Change between dq coordinate system and abc coordinate system is as shown by the equation：

After being decoupled by coordinate transform, the Mathematical Modeling for obtaining permanent magnet synchronous servo motor in dq coordinate system is described as follows：

Voltage equation：

Flux linkage equations：

Electromagnetic torque equation：T_em=p_n(ψ_pmi_q-ψ_pmi_d)=p_n[ψ_pmi_q+(L_d-L_q)·i_di_q]

Wherein：δ is stator, the angle of rotor flux, and Δ δ is variable angle amount, R_sFor stator resistance, u_d、i_dFor on d axle Component of voltage, current component；u_q、i_qFor the component of voltage on q axle, current component；ω_rAngular frequency is rotated for dq coordinate system； ψ_d、ψ_qFor magnetic linkage of the permanent magnet on dq axle；L is the equivalent armature inductance on dq coordinate system；ψ_sFor stator magnetic linkage, ψ_pmFor permanent magnetism The magnetic linkage that body is produced；p_nFor magnetic pole logarithm；

With magnetic linkage ψ under d axle_dAs a example by, it is assumed that t stator magnetic linkage is ψ_s(δ), through after a while, fixed to t+ Δ t Sub- magnetic linkage is changed into ψ_s(δ+Δ δ), if reference value isUnder d axle, magnetic linkage is ψ_d(δ+Δ δ), T_sFor switch periods.Then：

It is also possible to obtain with magnetic linkage ψ under q axle_q(δ+Δ δ), the above results are updated in voltage equation, you can realized The control of SVPWM input block.

Speed obtains the output of speed by the method for nonlinear Control, it is assumed that there are controlled quentity controlled variable V₁, then its output Difference is：

Wherein, J is rotary inertia, and B is coefficient of viscosity, T_LFor load torque,

Using first-order system configuration parameter V₁, i.e.,Wherein, K₁For control parameter undetermined,For Rotor velocity set-point；Then：

By governing speed parameter V₁, export i_qSet-point, final obtain torque reference value.

Fig. 2 is the voltage vector computing block diagram of the permanent magnet synchronous servo motor of the invention, and wherein, 1 is permanent magnet magnetic Magnetic linkage, 2 is stator, the angle δ of rotor flux, and 3 is rotation angular frequency_r, 4,5 is d, q axle magnetic linkage ψ_d、ψ_q, 6,7 is d, q axle electricity Stream i_d、i_q, 11,12 is d, q shaft voltage u_d、u_q, 13 is magnetic linkage computing unit.Fig. 3 is to select gain of parameter according to above-mentioned steps Torque simulation curve.

The above is only the better embodiment of the present invention, therefore all constructions according to described in present patent application scope, Equivalence changes or modification that feature and principle are done, are all included in the range of present patent application.

Claims (2)

1. a kind of permanent magnet synchronous servo motor control method, it is characterised in that speeds control is obtained by nonlinear control method Output valve, using the angled relationships between stator and rotor flux, determines the input of SVPWM unit, determines stator and rotor magnetic The relation of chain angle, determines the input of SVPWM unit, and then is realized to permanent magnetism by controlling stator and rotor flux angle The control of synchronous servo motor.By detecting the three-phase current of inverter output, it is considered to the coordinate transform under dq coordinate system and control Rule processed is calculated the electromagnetic torque of permanent magnet synchronous servo motor.By Voltage-Current model it is estimated that stator magnetic linkage Amplitude.As the angle δ of change stator, rotor flux can realize direct torque, i.e. compensate torque error by controlling Δ δ ΔT_e.Speeds control then adopts nonlinear control method, and velocity error then exports electromagnetic torque after speed regulator Reference value, by comparing, with the torque value for calculating, the controlled quentity controlled variable for obtaining angle afterwards.Voltage control is obtained by voltage equation again to refer to Order, calculates the action time of the voltage vector of selection using SVPWM, and then by the switch controlling signal of output inverter, Realize the direct torque to permanent magnet synchronous servo motor；

Wherein, speed obtains the output of speed by the method for nonlinear Control, it is assumed that there are controlled quentity controlled variable V₁, then its output Difference is：

$\frac{{\mathrm{d\ω}}_r}{dt}=-\frac{B}{J_s}{\mathrm{\ω}}_r+V_1$

J_sFor rotary inertia, B is coefficient of viscosity, ω_rAngular frequency is rotated for dq coordinate system；

T_LFor load torque, i_qFor the current component on q axle；ψ_pmFor the magnetic linkage that permanent magnet is produced；p_nFor magnetic pole logarithm.

Using first-order system configuration parameter V₁, i.e.,Wherein, K₁For control parameter undetermined,For rotor Angular speed set-point；Then：

$i_q=\frac{{\mathrm{JV}}_1+T_L}{1.5P_n{\mathrm{\ψ}}_{pm}};$

By governing speed parameter V₁, export i_qSet-point, final obtain torque reference value.

2. permanent magnet synchronous servo motor control method as claimed in claim 1, which adopts SVPWM control, SVPWM unit defeated Enter to be calculated as:

$\left\{\begin{array}{c}{u}_d=\frac{{\mathrm{d\ψ}}_d}{dt}-{\mathrm{\ω}}_r{\mathrm{\ψ}}_q+R_s{i}_d\\ u_q=\frac{{\mathrm{d\ψ}}_q}{dt}-{\mathrm{\ω}}_r{\mathrm{\ψ}}_d+R_s{i}_q\end{array}\right.$

$\frac{{\mathrm{d\ψ}}_d}{dt}=\frac{1}{T_s}\[-{\mathrm{\ψ}}_d\left(\mathrm{\δ}\right)+{\mathrm{\ψ}}_d(\mathrm{\δ}+\mathrm{\Δ}\mathrm{\δ})\]$

${\mathrm{\ψ}}_d(\mathrm{\δ}+\mathrm{\Δ}\mathrm{\δ})=\left|{\mathrm{\ψ}}_s^{*}\right|\left(\frac{\left|{\mathrm{\ψ}}_d\left(\mathrm{\δ}\right)\right|}{\left|{\mathrm{\ψ}}_s\left(\mathrm{\δ}\right)\right|}cos\right(\mathrm{\Δ}\mathrm{\δ})-\frac{\left|{\mathrm{\ψ}}_d\left(\mathrm{\δ}\right)\right|}{\left|{\mathrm{\ψ}}_s\left(\mathrm{\δ}\right)\right|}sin(\mathrm{\Δ}\mathrm{\δ}\left)\right)$

T stator magnetic linkage is ψ_s(δ), through after a while, it is changed into ψ to t+ Δ t stator magnetic linkage_s(δ+Δ δ), if reference It is worth and isUnder d axle, magnetic linkage is ψ_d(δ+Δ δ), T_sFor switch periods；δ is stator, the angle of rotor flux, and Δ δ is variable angle Amount, R_sFor stator resistance, u_d、i_dFor the component of voltage on d axle, current component；u_q、i_qDivide for the component of voltage on q axle, electric current Amount；ψ_d、ψ_qFor magnetic linkage of the permanent magnet on dq axle；L is the equivalent armature inductance on dq coordinate system；ψ_sFor stator magnetic linkage.