CN1558547A

CN1558547A - Non-linear dynamic calibration method for permanent magnetic synchronous motor

Info

Publication number: CN1558547A
Application number: CNA2004100217556A
Authority: CN
Inventors: 虹吕; 吕虹
Original assignee: GUILIN STARS POWER ELECTRORNICS CO Ltd
Current assignee: Guilin Stars Science And Technology Co ltd
Priority date: 2004-01-18
Filing date: 2004-01-18
Publication date: 2004-12-29
Anticipated expiration: 2024-01-18
Also published as: CN1279689C

Abstract

An AC motor three-phase current smoothing control device comprises a vector generator, a current closed-loop controller, and a central dot extraction electric network leading out the three-phase motor port voltage, each of which is connected with equivalent impedance, a star pattern connection is employed for common linking at dot Q, and a controller is introduced to mid-point Q electric potential for three phase current smoothing control, when the electric potential of the winding central dot deviates from null as the result of disequilibrium of the three phase current, the dot Q electric potential directly stimulates the winding mid-point potential and participates control.

Description

The Nonlinear Dynamic bearing calibration of permagnetic synchronous motor

(1) technical field

The present invention relates to a kind of permagnetic synchronous motor adjustment control method, be specially a kind of Nonlinear Dynamic bearing calibration of permagnetic synchronous motor.

(2) technical background

Common synchronous machine control has two kinds of variable frequency control and motor synchronizing controls.Variable frequency control promptly adopts frequency converter directly to drive synchronous machine and realizes open loop or speed closed loop control, because there are phenomenons such as natural oscillation, step-out in synchronous machine at equalising torque point place, common frequency converter is difficult to synchronous machine is effectively controlled particularly high-precision servo control, therefore less employing.The control of synchronous machine is based on autocontrol mode at present, promptly by detection rotor locus (d axial vector), controller makes the composite magnetic power vector (q axial vector) of motor stator three-phase current be positioned at leading or lags behind rotor field space vector 90 degree electrical degrees, like this, the electromagnetic torque maximum that obtains under the unitary current.When the armature supply of motor hour, motor electromagnetic torque maximum point occurs near electrical degree differs from 90 degree, and spends in the electrical degree scopes relation of electromagnetic torque value and electrical degree 360 and press sinusoidal variations substantially.But along with the increase of electric current, the pairing electrical degree of torque maximum point more and more departs from 90 degree.This phenomenon is when being understood that also current of electric strengthens, because of the factors such as demagnetization saturated, permanent magnetic material of magnetic flux cause the torque coefficient non-linearization.Therefore, if keep stator flux vector and rotor field vector to differ 90 degree all the time, when electric current is big, the maximum rotation Moment Point has been departed from the working point, the electromagnetic torque that unitary current produces descends, therefore electric efficiency reduces, and the peak acceleration that motor rotates descends the dynamic response characteristic variation.

(3) summary of the invention

The objective of the invention is to design a kind of Nonlinear Dynamic bearing calibration of permagnetic synchronous motor, carrying out Nonlinear Dynamic in order to the feature that torque angle displacement characteristic is distorted with the variation of electric current proofreaies and correct, in the hope of under any load running situation, be under the operating state of different electric currents, motor output torque is near the best operating point, improves the operational efficiency and the dynamic characteristic index of motor.

The permagnetic synchronous motor Nonlinear Dynamic bearing calibration of the present invention's design is: controller is according to the direction vector of the rotor space position vector angle control stator three-phase current of sensor, make the composite magnetic power vector of motor stator three phase windings be positioned at leading or lag behind the certain electrical degree of rotor field space vector, it comprises the steps:

The 1st step, on motor stator winding, feed the three-phase sine-wave electric current, change the effective value size of electric current, motor electromagnetic torque value when under each current value, measuring electrical degree differences different between motor stator and the rotor field vector, make electromagnetic torque and electric angle relation curve under one group of different current value, i.e. one group of torque angle displacement characteristic curve, and find out the electric angle of the torque maximum of points correspondence on each bar torque angle displacement characteristic curve;

In the 2nd step, data are deposited in the controller;

The 3rd step, when controller is implemented control, calculate the electrical degree of the rotor field space vector of motor earlier by sensor measurement, and be converted into electric angle θ, according to institute's stored data value, find the torque angle displacement characteristic curve that records under the close with it electric current by stator actual current size, obtain the electric angle φ of maximum torque point correspondence under this electric current, controller is according to the electric angle φ control three-phase stator winding resultant magnetic field direction vector of residing electric angle θ in rotor field and maximum torque point correspondence, guarantee electric angle to breakdown torque under should electric current, proofread and correct thereby the moment-current relationship that guarantees motor obtains Nonlinear Dynamic.

Adopt method of the present invention to make controller adapt to voluntarily with the feature that the variation of electric current is distorted to the permagnetic synchronous motor torque angle displacement characteristic, promptly under different current of electric, dynamically the electric angle between control q axial vector and the d axial vector is offset along with the skew of torque angle displacement characteristic, all the time follow the variation of maximum moment point, can improve the operational efficiency and the dynamic characteristic index of motor in that motor output torque-stator current characteristic is near the best operating point.The invention solves " torque coefficient is non-linear " on the traditional concept and be difficult to the problem of real-time dynamic correcting, make and control especially by synchronous machine SERVO CONTROL reaches more high efficiency, better dynamic speed adjustment characteristic.

(4) description of drawings

One group of torque angle displacement characteristic curve synoptic diagram that Fig. 1 records under different electric currents for permagnetic synchronous motor.

(5) embodiment

The Nonlinear Dynamic bearing calibration of following examples explanation permagnetic synchronous motor of the present invention.

The 1st step, torque angle displacement characteristic is measured, be to carry out the measurement of correlation that carries out before the dynamic calibration, on motor stator winding, feed the three-phase sine-wave electric current in advance, change the size of current effective value, as get 30%, 90%, 150%, 210%, 270% of rated current, motor electromagnetic torque value when under each current value, measuring electrical degree differences different between motor stator and the rotor field vector, get abundant measurement point, obtain electromagnetic torque and electric angle relation curve under one group of different current value, i.e. one group of torque angle displacement characteristic curve, as shown in Figure 1.As seen, when electric current increased, the electric angle of corresponding maximum electromagnetic torque or angular interval had increased offset θ on the basis of desirable electrical degree 90 degree among the figure.

In the 2nd step, the electric angle or the angular interval of torque maximum of points correspondence are found out in the storage of relevant data on each bar torque angle displacement characteristic curve, data are deposited in the controller.The data of storing in advance in the controller are to have the electromagnetic torque of several features point and the list data of electric angle relation under the different current values.Or be the operation method that the sign list data electromagnetic torque that generates according to list data and electric angle concern rule.The two all can obtain the electric angle side-play amount of output vector under the different loads electric current.

The 3rd step, when controller is implemented control, calculate the electrical degree of the rotor field space vector of motor earlier by sensor measurement, and be converted into electric angle θ, according to institute's stored data value, find by stator actual current size and to record the torque angle displacement characteristic curve under the close with it electric current, obtain the electric angle φ of maximum torque point correspondence under this electric current, controller is according to the electric angle φ control three-phase stator winding resultant magnetic field direction vector of residing electric angle θ in rotor field and maximum torque point correspondence.The leading rotor field of resultant magnetic field vector vector as the need three-phase stator winding then adopts the resultant magnetic field vector electrical degree of θ+φ as three phase windings; Resultant magnetic field vector as the need three-phase stator winding lags behind the rotor field vector, then adopts the resultant magnetic field vector electrical degree of θ-φ as three phase windings.Guarantee electric angle to breakdown torque under should electric current, thereby the Nonlinear Dynamic that obtains that guarantees the moment-current relationship of motor is proofreaied and correct.

When searching the electrical degree side-play amount of corresponding maximum electromagnetic torque by actual current, can adopt above-mentioned approximation method, perhaps according to the actual current size find out in advance storage the torque angle displacement characteristic curve of close electric current, carry out the electrical degree side-play amount that interpolation operation obtains maximum torque point correspondence under the actual current according to the data of storage in advance.

Claims

The Nonlinear Dynamic bearing calibration of 1 one kinds of permagnetic synchronous motors, control the vector of stator three-phase current by controller according to the rotor space position vector angle of sensor, make the composite magnetic power vector of motor stator three phase windings be positioned at leading or lag behind the certain electrical degree of rotor field space vector; It is characterized by also and comprise the steps:

The 1st step, on the armature winding, feed the three-phase sine-wave electric current, change the effective value of electric current, motor electromagnetic torque value when under each current value, measuring electrical degree differences different between motor stator and the rotor field vector, make electromagnetic torque and electric angle relation curve under one group of different current value, i.e. one group of torque angle displacement characteristic curve, and find out the electric angle of the torque maximum of points correspondence on each bar torque angle displacement characteristic curve

In the 2nd step, data are deposited in the controller;

The 3rd step, when controller is implemented control, calculate the electrical degree of the rotor field space vector of motor earlier by sensor measurement, and be converted into electric angle θ, according to institute's stored data value, find the torque angle displacement characteristic curve that records under the close with it electric current by stator actual current size, obtain the electric angle φ of maximum torque point correspondence under this electric current, controller is according to the electric angle φ control three-phase stator winding resultant magnetic field direction vector of residing electric angle θ in rotor field and maximum torque point correspondence.
The Nonlinear Dynamic bearing calibration of 2 permagnetic synchronous motors according to claim 1 is characterized by:

When the torque angle displacement characteristic curve is decided in wherein said the 1st pacing, on motor stator winding, feed the three-phase sine-wave electric current in advance, change the effective value of electric current, as get 30%, 90%, 150%, 210%, 270% of rated current, motor electromagnetic torque value when under each current value, measuring electrical degree differences different between motor stator and the rotor field vector, get enough measurement points, obtain electromagnetic torque and electric angle relation curve, i.e. one group of torque angle displacement characteristic curve under one group of different current value.
The Nonlinear Dynamic bearing calibration of 3 permagnetic synchronous motors according to claim 1 and 2 is characterized by:

Wherein said when the 3rd step, controller was implemented control, the leading rotor field of the resultant magnetic field vector vector as the need three-phase stator winding then adopts the resultant magnetic field vector electrical degree of θ+φ as three phase windings; Resultant magnetic field vector as the need three-phase stator winding lags behind the rotor field vector, then adopts the resultant magnetic field vector electrical degree of θ-φ as three phase windings.
The Nonlinear Dynamic bearing calibration of 4 permagnetic synchronous motors according to claim 1 and 2 is characterized by:

In wherein said the 2nd step, the data of storing in advance in the controller are to have the electromagnetic torque of several features point and the list data of electric angle relation under the different current values; Or be the operation method that the sign list data electromagnetic torque that generates according to list data and electric angle concern rule.
The Nonlinear Dynamic bearing calibration of 5 permagnetic synchronous motors according to claim 1 and 2 is characterized by:

Wherein said when the 3rd step, controller was implemented control, find out the torque angle displacement characteristic curve of the close electric current of storage in advance according to the actual current size, carry out the electrical degree side-play amount that interpolation operation obtains maximum torque point correspondence under the actual current according to the data of storage in advance.