CN106992733A - Vehicle-mounted internal permanent magnet synchronous motor control method - Google Patents

Abstract

The present invention provides a kind of vehicle-mounted internal permanent magnet synchronous motor control method, it is characterised in that comprise the following steps：First, permagnetic synchronous motor mathematical modeling, including voltage equation model, electromagnetic torque equation model and torque balance equation model are set up；2nd, design sliding-mode surface and sliding formwork control ratio, sliding formwork control is realized to motor electromagnetic torque；3rd, based on electromagnetic torque value T_e, decompose and obtain quadrature axis current i_qWith direct-axis current i_d；4th, based on i_q、i_d、U_dc, ac-dc axis voltage give U'_qAnd U'_d, decompose and obtain ac-dc axis given value of current valueWith5th,WithDecomposition obtains ac-dc axis voltage and gives U'_qAnd U'_d.6th, based on U'_qAnd U'_d, two-phase stationary voltages U is obtained through coordinate transform_αAnd U_β, with U_αAnd U_βFor input, three-phase given voltage U is obtained after modulation pattern_a、U_b、U_cDrive inverter and motor work.The control method of the present invention can guarantee that stable operation of the motor under any operating mode.

Description

Vehicle-mounted internal permanent magnet synchronous motor control method

Technical field

The present invention relates to Control of Electric Vehicles field, more particularly to a kind of vehicle-mounted internal permanent magnet synchronous motor controlling party Method.

Background technology

Internal permanent magnet synchronous motor has wide speed regulating range, big torque current ratio, high power density, high efficiency, Gao Gong Rate factor and low noise and other advantages, are widely used in the industrial circles such as electric automobile at present.The synchronous electricity of vehicle-mounted built-in type permanent-magnet The basic demand of machine drive system is：Require that big torque can be exported during low speed, will to meet the performances such as starting, acceleration and climbing Ask；Require that wide speed regulating range can be realized during high speed, with meet run at high speed, the performance requirement such as overtake other vehicles.

Vehicle-mounted internal permanent magnet synchronous motor is in low speed permanent torque operation phase common maximum torque per ampere control side Method has look-up table and curve-fitting method.Because look-up table real-time and authenticity are poor, calculate complicated, take a large amount of memory cell, Project Realization is not easy to, therefore frequently with curve fitting algorithm in engineering practice.However, using during curve fitting algorithm due to hand over Shaft current and the relational expression of electromagnetic torque are difficult to solve, and operational data amount is big, and flow is relative complex, and its relational expression is by rotor magnetic Chain, some variable elements influence such as ac-dc axis inductance, the matched curve of anti-solution out is influenceed larger by variable element.

Vehicle-mounted internal permanent magnet synchronous motor is in the high speed output-constant operation stage frequently with weak-magnetic speed-regulating control method.Compare Common weak magnetic control strategy has computing method of formula, gradient descent method, look-up table and advance angle weak magnetic method etc..

The subject matter that various weak magnetic methods are solved includes：Avoid the saturation of current regulator；Motor is set to turn in perseverance It is steady excessive between square and invariable power region；Improve the utilization rate of DC bus-bar voltage；Avoid the change of the parameter of electric machine may be right The influence that control system is produced；Avoid intercoupling between ac-dc axis electric current.In view of computing cost, stability and weak magnetic Efficiency etc. integrates factor, in various weak magnetic methods, and advance angle weak magnetic method is easier to a kind of of realization and reliably extensively should Weak magnetic method, therefore the present invention deploys to study and improves to lift its weak magnetic efficiency to the method.Advance angle method can increase The robust performance of forceful electric power machine, the utilization rate for improving inverter DC bus-bar voltage, allow motor smoothly in permanent torque and perseverance Switched between power region.But this method situation not reverse to electric current is accounted for, when rotating speed or load torque are negative To it is given cause current of electric reverse when system will be out of control；And the amplitude to electric current is not limited, when voltage rise causes Systematic function will deteriorate rapidly when current regulator enters saturation state.

The content of the invention

It is an object of the invention to put forward vehicle-mounted internal permanent magnet synchronous motor control method, to solve the above problems.

Present invention employs following technical scheme：

A kind of vehicle-mounted internal permanent magnet synchronous motor control method, it is characterised in that comprise the following steps：

Step 1: according to the specific parameter of electric machine, permagnetic synchronous motor mathematical modeling is set up, including voltage equation mould Type, electromagnetic torque equation model and torque balance equation model；

Step 2: based on speed error, design sliding-mode surface and sliding formwork control ratio realize sliding formwork control to motor electromagnetic torque System；

Step 3: based on electromagnetic torque value T_e, with torque capacity electric current than strategy for foundation, decomposition obtains quadrature axis current i_q With direct-axis current i_d；

Step 4: based on quadrature axis current i_q, direct-axis current i_d, DC bus-bar voltage U_dc, ac-dc axis voltage give U'_qAnd U '_d, ac-dc axis given value of current value is obtained using weak magnetic model as according to decompositionWith

Step 5: based on ac-dc axis given value of current valueWithDecoupled through electric current loop anti-saturation adjuster and electric voltage feed forward Link collective effect, which is decomposed, obtains the given U' of ac-dc axis voltage_qAnd U'_d；

Step 6: giving U' based on voltage_qAnd U'_d, two-phase stationary voltages U is obtained through coordinate transform_αAnd U_β, with U_αAnd U_βFor Input, obtains three-phase given voltage U after modulation pattern_a、U_b、U_cDrive inverter and motor work.

Further, vehicle-mounted internal permanent magnet synchronous motor control method of the invention, can also have the feature that：

In step one,

Stator voltage equation is：

Electromagnetic torque equation is：

In formula, R_s- stator resistance；P=d/dt-differential operator；i_d, i_q；L_d, L_q- d-axis and quadrature axis current and inductance； ω_e=n_p·ω_r—ω_eFor angular rate, n_pFor motor number of pole-pairs, ω_rFor mechanical angular speed；ψ_f- rotor permanent magnet and stator The magnetic linkage of winding interlinkage,

The torque equation of three-phase permanent magnet synchronous motor is as follows：

Further, vehicle-mounted internal permanent magnet synchronous motor control method of the invention, can also have the feature that：Order E is speed error, thenIt can be obtained by formula (3)：

In formulaFor the rate of change of speed error,Lead, make for the second order of speed errorThen formula (4) can Arrange and be：

Designing sliding-mode surface isWherein c must is fulfilled for Hurwitz conditions, i.e. c ＞ 0, steady according to Li Yapu loves Qualitative criteria, when V positive definites and with continuous first-order partial derivative, and V first-order partial derivative negative semidefinite, then it is exactly stable , defining Li Yapu love functions isIt is then guaranteeDesigning sliding formwork control ratio is：

Further, vehicle-mounted internal permanent magnet synchronous motor control method of the invention, can also have the feature that：Step In rapid three,

Foundation sets up torque capacity electric current than model with following formula (7) and formula (8),

Further, vehicle-mounted internal permanent magnet synchronous motor control method of the invention, can also have the feature that：Step In rapid four, compareWithSize carry out operation phase of decision systems, whenWhen, Illustrate that now motor terminal voltage is less than voltage limit U_smax, using maximum torque per ampere control strategy；WhenWhen, illustrate that now motor terminal voltage reaches the limit values U_smax, using weak magnetic control strategy, whenWhen, redistribute i after taking the integrated adjuster output angle θ of its difference (between-pi/2 to 0)_q's Electric current, makes original i_qA part is used as i_dGo magnetic component, while itself component also reduces, realize weak magnetic speed-up.

Further, vehicle-mounted internal permanent magnet synchronous motor control method of the invention, can also have the feature that：Step In rapid five,

(b) electric voltage feed forward is decoupled

Obtained according to formula (1)

In formula- direct-axis current rate of change；

- quadrature axis current rate of change,

By formula (9) it can be seen that i_dAnd i_qIntercouple, be a kind of Nonlinear system structure, it is impossible to independent by d, q axle Control, if L_dAnd L_qIt is larger, as this coupling of the rising of rotating speed can bring influence to electric current and torque response, for independence Control i_dAnd i_q, the present invention is using the method for feedforward compensation to i_dAnd i_qDecoupled,

Defining offset voltage formula is

U' in formula_dFor the direct-axis voltage value after compensation；U'_qFor the quadrature-axis voltage value after compensation,

Formula (10) is brought into formula (9) to obtain

Further, vehicle-mounted internal permanent magnet synchronous motor control method of the invention, can also have the feature that：Step In rapid six,

In real process, when motor operation is in the weak magnetic stage, given voltage is generally large, therefore ovennodulation occurs Phenomenon, need to be to T when there is ovennodulation_x、T_yIt is adjusted, in order to further improve the utilization to inverter DC bus-bar voltage Rate, improves weak magnetic speed-up width, and the present invention carries out inversion using a kind of SVPWM overmodulation method to DC bus-bar voltage, specifically It is as follows, (a) T_x＞ T_yWhen

Work as T_x+T_y/ 2 ＞ T_sWhen, illustrate outside polygon, now T_x=T_s, T_y=0；

Work as T_x+T_y/ 2 ＜ T_sAnd T_x+T_y＞ T_sWhen illustrate ovennodulation, now T_x'=[T_x/(T_x+T_y)]·T_s, T_y'= [T_y/(T_x+T_y)]·T_s；

Work as T_x+T_y/ 2 ＜ T_sAnd T_x+T_y＜ T_sWhen illustrate no ovennodulation, now T_x=T_x,T_y=T_y,

(b)T_x＜ T_yWhen

Work as T_x/2+T_y＞ T_sWhen, illustrate outside polygon, now T_x=0, T_y=T_s；

Work as T_x/2+T_y＜ T_sAnd T_x+T_y＞ T_sWhen illustrate ovennodulation, now T_x'=[T_x/(T_x+T_y)]·T_s, T_y'= [T_y/(T_x+T_y)]·T_s；

Work as T_x/2+T_y＜ T_sAnd T_x+T_y＜ T_sWhen illustrate no ovennodulation, now T_x=T_x,T_y=T_y,

Wherein, T_xTo expect the component of voltage on the adjacent axle in voltage vector bottom；T_yTo expect the adjacent axle in voltage vector top On component of voltage；T_sTo use the cycle.

The beneficial effect of invention

The vehicle-mounted internal permanent magnet synchronous motor control method of the present invention, the control problem existed for low-speed stage, this Invention, using speed error as the input of rotating speed outer shroud sliding mode controller, passes through the design of sliding Mode Algorithm using the thought of feedback Electromagnetic torque is decomposited as the output of controller, then quadrature axis is decomposited using the relation between quadrature axis current and electromagnetic torque Electric current, recycles the relation between direct-axis current and quadrature axis current to decomposite direct-axis current and is respectively controlled, not only eliminate A large amount of mathematical operations, additionally it is possible to which coordination control is carried out to electric current and torque.

For the deficiency of high speed stage advance angle weak magnetic method, a kind of improved weak magnetic is devised in the high speed stage present invention Method is allocated to the electric current in motor whole frequency range.By having to ac-dc axis electric current while considering that electric current is reverse Effect distribution produces corresponding demagnetizing current, it is ensured that stable operation of the motor under any operating mode.Also, it is weak designed by the present invention The problem of magnet ring section efficiently solves smooth transition between the clipping problem and permanent torque of stator current and invariable power region.

Meanwhile, to lift the control performance of whole weak magnetic control system, the present invention also takes following aggregate measures to be lifted The dynamic quality of control system.In the base fast above weak magnetic field operation stage, for the saturated phenomenon for preventing electric current loop to be likely to occur, Electric current loop substitutes traditional pi regulator using position model anti-saturation integral controller；Introduce electric voltage feed forward decoupling link and eliminate friendship directly The influence that the coupled problem of shaft current may be brought to the stability of a system；Dc bus electricity is improved using a kind of Overmodulation Method The utilization rate of pressure.In order to improve the dynamic responding speed of motor speed and torque, while in order to weaken parameter of electric machine change to control A kind of influence that the stability of a system processed is caused, the controller that the present invention devises der Geschwindigkeitkreis sliding moding structure substitutes conventional PI control Device.The vehicle-mounted internal permanent magnet synchronous motor weak magnetic vector control system designed by the present invention is lifted by above aggregate measures Weak magnetic property and control performance, and then improve electric automobile stability and security.

Brief description of the drawings

Fig. 1 is the schematic diagram of sliding mode controller；

Fig. 2 is torque capacity electric current than algorithm principle figure；

Fig. 3 is weak magnetic part design principle figure；

Fig. 4 is position model anti-saturation pi regulator schematic diagram；

Fig. 5 is feedforward angle coupling block diagram；

Fig. 6 is ovennodulation implementation process figure；

Fig. 7 is the internal permanent magnet synchronous motor weak magnetic vector control system figure based on sliding moding structure；

Rotational speed setup and actual value when Fig. 8 rotating speeds are from 600rad/s to 5000rad/s；

Weak magnetic angle output valve when Fig. 9 rotating speeds are from 600rad/s to 5000rad/s；

Torque output value when Figure 10 rotating speeds are from 600rad/s to 5000rad/s；

Rotational speed setup and actual value when Figure 11 rotating speeds are from 600rad/s to 5000rad/s during nonreactive saturated controller；

Weak magnetic angle value when Figure 12 rotating speeds are from 600rad/s to 5000rad/s during nonreactive saturated controller；

Torque output value when Figure 13 rotating speeds are from 600rad/s to 5000rad/s during nonreactive saturated controller；

Rotational speed setup and actual value when Figure 14 rotating speeds are from 600rad/s to -5000rad/s；

Weak magnetic angle output valve when Figure 15 rotating speeds are from 600rad/s to -5000rad/s；

Torque output value when Figure 16 rotating speeds are from 600rad/s to -5000rad/s；

Rotational speed setup and actual value when torque reference is 5 to -10 when Figure 17 rotating speeds are from 600rad/s to 5000rad/s；

Weak magnetic angle when torque reference is 5Nm to -10Nm when Figure 18 rotating speeds are from 600rad/s to 5000rad/s is defeated Go out value；

Torque output when torque reference is 5Nm to -10Nm when Figure 19 rotating speeds are from 600rad/s to 5000rad/s Value.

Embodiment

Illustrate the embodiment of the present invention below in conjunction with accompanying drawing.

The vehicle-mounted internal permanent magnet synchronous motor weak magnetic vector control system of the present invention, comprises the following steps：

Step 1: according to the specific parameter of electric machine, permagnetic synchronous motor mathematical modeling is set up, including voltage equation mould Type, electromagnetic torque equation model and torque balance equation model.

Stator voltage equation：

Electromagnetic torque equation：

In formula, R_s- stator resistance；P=d/dt-differential operator；i_d, i_q；L_d, L_q- d-axis and quadrature axis current and inductance； ω_e=n_p·ω_r—ω_eFor angular rate, n_pFor motor number of pole-pairs, ω_rFor mechanical angular speed；ψ_f- rotor permanent magnet and stator The magnetic linkage of winding interlinkage.

The torque equation of three-phase permanent magnet synchronous motor is as follows：

Step 2: based on speed error, design sliding-mode surface and sliding formwork control ratio realize sliding formwork control to motor electromagnetic torque

It is speed error to make e, thenIt can be obtained by formula (3)：

In formulaFor the rate of change of speed error,Led for the second order of speed error.OrderThen formula (4) it can arrange and be：

Designing sliding-mode surface isWherein c must is fulfilled for Hurwitz conditions, i.e. c ＞ 0.It is steady according to Li Yapu loves Qualitative criteria, when V positive definites and with continuous first-order partial derivative, and V first-order partial derivative negative semidefinite, then it is exactly stable 's.Defining Li Yapu love functions isIt is then guaranteeDesigning sliding formwork control ratio is：

Sliding mode controller design is as shown in Figure 1.

Step 3: based on electromagnetic torque value T_e, with torque capacity electric current than strategy for foundation, decomposition obtains quadrature axis current i_q With direct-axis current i_d,

Compare model according to torque capacity electric current is set up with following formula (7) and formula (8).

The present invention builds simulation model according to formula (7) and (8) and decomposites i_dAnd i_qIt is respectively controlled, torque capacity electric current It is more as shown in Figure 2 than modelling.

Step 4: based on quadrature axis current i_q, direct-axis current i_d, DC bus-bar voltage U_dc, ac-dc axis voltage give U'_qAnd U '_d, ac-dc axis given value of current value is obtained using weak magnetic model as according to decompositionWith

Weak magnetic principle design is as shown in figure 3, by comparingWithSize carry out the operations of decision systems Stage.WhenWhen, illustrate that now motor terminal voltage is less than voltage limit U_smax, turned using maximum Square electric current compares control strategy.WhenWhen, illustrate that now motor terminal voltage reaches the limit values U_smax, using weak Magnetic control strategy.WhenWhen, take the integrated adjuster output angle θ of its difference (between-pi/2 to 0) After redistribute i_qElectric current, make original i_qA part is used as i_dGo magnetic component, while itself component also reduces, so as to reach To weak magnetic speed-up purpose.

Step 5: based on ac-dc axis given value of current valueWithThrough electric current loop anti-saturation adjuster and electric voltage feed forward decoupling ring Section collective effect, which is decomposed, obtains the given U' of ac-dc axis voltage_qAnd U'_d。

(a) anti-saturation pi regulator

When the error in some direction occurs in adjuster, due to adding up for integration, the output of adjuster can continue to increase, The a certain moment makes executing agency reach capacity position.If now adjuster output continues to increase, its output valve is just by saturation.When anti- When occurring to error, the output valve of adjuster begins to exit from saturation region.But now because executing agency has reached its pole Extreme position, it is impossible to making a change with reverse error immediately, so as to cause systematic function to deteriorate rapidly.When saturation direction with System can not voluntarily exit saturation when its direction of error is equidirectional, at this moment can be by the output after controller output valve and its amplitude limit The difference of value, which is multiplied by, moves back saturation coefficient K_cMake difference with original integration error originated from input value to input as new integration, so as to reduce product Divide error, and then reduce integration amount, finally exit saturation.Integral compensator design is as shown in Figure 4.

(b) electric voltage feed forward is decoupled

Obtained according to formula (1)

In formula- direct-axis current rate of change；

- quadrature axis current rate of change.

By formula (9) it can be seen that i_dAnd i_qIntercouple, be a kind of Nonlinear system structure, it is impossible to independent by d, q axle Control, if L_dAnd L_qIt is larger, as this coupling of the rising of rotating speed can bring influence to electric current and torque response, for independence Control i_dAnd i_q, the present invention is using the method for feedforward compensation to i_dAnd i_qDecoupled.

Defining offset voltage formula is

U ' in formula_dDirect-axis voltage value after-compensation；

U′_qQuadrature-axis voltage value after-compensation.

Formula (10) is brought into formula (9) to obtain

From formula (11) as can be seen that the state equation after overcompensation is not coupled.Electric current loop Feedforward Decoupling module is set Meter is as shown in Figure 5.

Step 6: giving U' based on voltage_qAnd U'_d, two-phase stationary voltages U is obtained through coordinate transform_αAnd U_β, with U_αAnd U_βFor Input, obtains three-phase given voltage U after modulation pattern_a、U_b、U_cDrive inverter and motor work.

In real process, when motor operation is in the weak magnetic stage, given voltage is generally large, therefore ovennodulation occurs Phenomenon.Need to be to T when there is ovennodulation_x、T_yIt is adjusted.In order to further improve the utilization to inverter DC bus-bar voltage Rate, improves weak magnetic speed-up width, and the present invention carries out inversion using a kind of SVPWM overmodulation method to DC bus-bar voltage, specifically It is as follows.(a)T_x＞ T_yWhen

Work as T_x+T_y/ 2 ＞ T_sWhen, illustrate outside polygon, now T_x=T_s, T_y=0；

Work as T_x+T_y/ 2 ＜ T_sAnd T_x+T_y＞ T_sWhen illustrate ovennodulation, now T_x'=[T_x/(T_x+T_y)]·T_s, T_y'= [T_y/(T_x+T_y)]·T_s；

Work as T_x+T_y/ 2 ＜ T_sAnd T_x+T_y＜ T_sWhen illustrate no ovennodulation, now T_x=T_x,T_y=T_y。

(b)T_x＜ T_yWhen

Work as T_x/2+T_y＞ T_sWhen, illustrate outside polygon, now T_x=0, T_y=T_s；

Work as T_x/2+T_y＜ T_sAnd T_x+T_y＞ T_sWhen illustrate ovennodulation, now T_x'=[T_x/(T_x+T_y)]·T_s, T_y'= [T_y/(T_x+T_y)]·T_s；

Work as T_x/2+T_y＜ T_sAnd T_x+T_y＜ T_sWhen illustrate no ovennodulation, now T_x=T_x,T_y=T_y。

Wherein, T_xTo expect the component of voltage on the adjacent axle in voltage vector bottom；T_yTo expect the adjacent axle in voltage vector top On component of voltage；T_sTo use the cycle.

SVPWM overmodulation the Realization of Simulation flow chart is as shown in Figure 6.

By taking following motor model as an example, illustrate that one of the present invention is specific practical.

Busbar voltage U_dc=600V, subcarrier time T=0.0001s, d-axis inductance L_d=0.004H, quadrature axis inductance L_q= 0.008H, stator resistance R_s=2.875 Ω, rotor flux ψ_f=0.175Wb, rotary inertia J=0.029kgm², viscous damping Coefficient F=0Nms, number of pole-pairs n_p=2, maximum voltageMaximum current I_smax=80A, Load torque T_L5Nm to 10Nm step during for 0.4s, simulation time is set to 1.8s.Based on the built-in of sliding moding structure Permagnetic synchronous motor weak magnetic vector system general diagram is as shown in Figure 7.

Fig. 8 be rotating speed from 600rad/s to 5000rad/s when rotational speed setup and actual value, Fig. 9 show rotating speed from Weak magnetic angle output valve during 600rad/s to 5000rad/s, when Figure 10 shows rotating speed from 600rad/s to 5000rad/s Torque output value.

Fig. 8 to Figure 10 be respectively rotating speed from 600rad/s to 5000rad/s when PI controllers and sliding mode controller control This patent propose weak magnetic method, PI controllers and sliding mode controller control traditional advance angle weak magnetic method rotary speed setting value With actual value, weak magnetic angle and electromagnetic torque output valve.

Under identical operating mode, the negative more systems of angle illustrate that its terminal voltage is more more than maximum voltage, weak magnetic degree Deeper, required output torque is bigger, and system is lower to DC bus-bar voltage utilization rate, and system weak magnetic property is poorer.

It is can be seen that in from Fig. 8 to Figure 10 under same rotational speed, this hair controlled using sliding mode controller and PI controllers The angle output absolute value of the weak magnetic system of bright proposition, the tradition than being controlled using sliding mode controller and PI controllers is advanced respectively The output absolute value of angle weak magnetic system is small, and sliding mode controller of the present invention and PI controller control system rotating speeds are followed and compared respectively Advance angle sliding mode controller and PI controller systems are more smooth, and torque output is controlled than advance angle sliding mode controller and PI respectively Device system is smaller, illustrates the validity of weak magnetic method proposed by the present invention.

Under identical operating mode, the angle output of sliding mode controller system and advance angle sliding mode controller system of the present invention is absolute Value is small, and the angle output absolute value than PI controller systems of the present invention and advance angle PI controller systems is small respectively, and two Planting sliding mode controller system, than two kinds PI controller systems rotating speeds outputs are more steady respectively, and torque output is smaller, illustrates to slide Validity of the mould control method to raising weak magnetic property.

Figure 11 to Figure 13 be respectively rotating speed from 600rad/s to 5000rad/s when sliding mode controller control the present invention proposition Weak magnetic method rotary speed setting value and actual value, weak magnetic angle and electromagnetic torque output valve when whetheing there is anti-saturation integrator.Figure 11 Rotational speed setup and actual value when showing rotating speed from 600rad/s to 5000rad/s during nonreactive saturated controller；Figure 12 is shown Weak magnetic angle value when rotating speed is from 600rad/s to 5000rad/s during nonreactive saturated controller；Figure 13 show rotating speed from Torque output value during 600rad/s to 5000rad/s during nonreactive saturated controller.

It can be seen that from Figure 11 to Figure 13 under identical operating mode, the weak magnetic system proposed by the present invention of sliding mode controller control It is bigger than original system that system removes the output absolute value of the weak magnetic angle after anti-saturation control device, and removes detent torque after anti-saturation controller Become big, rotating speed becomes unsmooth, illustrate validity of the electric current loop anti-saturation controller to raising weak magnetic property.

Figure 14 to Figure 16 is changed above-mentioned 4 when rotational speed setup is steps of the 0.2s from 600rad/s to -5000rad/s respectively Plant system rotary speed setting value and actual value, weak magnetic angle and electromagnetic torque output valve.Figure 17 to Figure 19 is above-mentioned 4 kinds of systems respectively Rotational speed setup when changing 5Nm to -10Nm step when load torque is 0.4s when rotating speed is from 600rad/s to 5000rad/s Value and actual value, weak magnetic angle and electromagnetic torque output valve.When Figure 14 shows rotating speed from 600rad/s to -5000rad/s Rotational speed setup and actual value；Weak magnetic angle output valve when Figure 15 shows rotating speed from 600rad/s to -5000rad/s；Figure 16 Torque output value when showing rotating speed from 600rad/s to -5000rad/s；Figure 17 show rotating speed from 600rad/s to Rotational speed setup and actual value when torque reference is 5Nm to -10Nm during 5000rad/s；Figure 18 show rotating speed from Weak magnetic angle output valve when torque reference is 5Nm to -10Nm during 600rad/s to 5000rad/s；Figure 19, which is shown, to be turned Torque output value when torque reference is 5Nm to -10Nm when speed is from 600rad/s to 5000rad/s.

It can be seen that from Figure 14 to Figure 19 under rotating speed and the given external disturbance of torque reversal, the sliding formwork under identical operating mode Controller and the weak magnetic system proposed by the present invention of PI controllers control remain to even running, and sliding mode controller and PI controllers Traditional advance angle system of control is out of hand.

Analyzed more than and can obtain to draw a conclusion：1. by the simulation comparison with PI controllers, sliding formwork control is illustrated Validity of the device to raising internal permanent magnet synchronous motor runnability.2. the emulation pair with nonreactive saturated controller system is passed through Than illustrating validity of the electric current loop anti-saturation controller for raising internal permanent magnet synchronous motor weak magnetic property.3. by with The simulation comparison of traditional advance angle weak magnetic system, illustrates the effective of internal permanent magnet synchronous motor weak magnetic system proposed by the present invention Property.

The beneficial effects of the invention are as follows：1. low-speed stage design maximum torque per ampere control algorithm, coordinating torque and The relation of electric current, reduces stator current output, reduction loss while electric automobile low speed operation phase performance is met.2. exist High speed stage studies weak magnetic control algolithm, devises a reliable weak magnetic system to improve weak magnetic efficiency, coordinates rotating speed and magnetic Logical relation, reaches the high-revolving purpose of liter, to meet performance of the electric automobile during high-speed cruising by reducing magnetic flux It is required that.Designed weak magnetic method can guarantee that stable operation of the motor under any operating mode.Meanwhile, the weak magnetic method is effectively solved Determined stator current clipping problem and permanent torque and invariable power region between smooth transition the problem of.3. it is directed to high speed weak magnetic The saturation problem of intercoupling between ac-dc axis electric current and ac-dc axis electric current during control, to prevent high-speed cruising stage current ring Intercoupling between the current saturation and ac-dc axis electric current that are likely to occur produces influence on the stability of a system, and the present invention is to position model Anti-saturation algorithm and Feedforward Decoupling algorithm are studied, it is ensured that the stability in electric automobile high-speed cruising stage.4. it is whole to ensure The stability of individual running, improves the response speed of torque and rotating speed, improves control accuracy, and the present invention is carried out to sliding Mode Algorithm Research, devises a stable rotating speed outer shroud Sliding mode control device.

It is expected that the feasibility and prospect of invention popularization and application

Can be to domestic and international popularization.With becoming increasingly popular for new-energy automobile, electric automobile high speed weak magnetic controlled level shows Obtain more and more important, be the important embodiment of electric automobile performance quality, major new-energy automobiles manufacture commercial cities electronic both at home and abroad Automobile weak magnetic efficiency is used as the leading indicator for weighing product quality quality.

How the technology of the present invention is mainly around lifting electric automobile weak magnetic efficiency, it is ensured that the security of electric automobile operation, With wide promotional value.

Claims (7)

1. a kind of vehicle-mounted internal permanent magnet synchronous motor control method, it is characterised in that comprise the following steps：

Step 1: permagnetic synchronous motor mathematical modeling is set up, including stator voltage equation model, electromagnetic torque equation model With torque balance equation model；

Step 2: based on speed error, design sliding-mode surface and sliding formwork control ratio realize sliding formwork control to motor electromagnetic torque；

Step 3: based on electromagnetic torque value T_e, with torque capacity electric current than strategy for foundation, decomposition obtains quadrature axis current i_qWith it is straight Shaft current i_d；

Step 4: based on quadrature axis current i_q, direct-axis current i_d, DC bus-bar voltage U_dc, ac-dc axis voltage give U'_qAnd U'_d, with Weak magnetic model is to obtain ac-dc axis given value of current value according to decompositionWith

Step 5: based on ac-dc axis given value of current valueWithThrough electric current loop anti-saturation adjuster and electric voltage feed forward decoupling link Collective effect, which is decomposed, obtains the given U' of ac-dc axis voltage_qAnd U'_d；

Step 6: giving U' based on voltage_qAnd U'_d, two-phase stationary voltages U is obtained through coordinate transform_αAnd U_β, with U_αAnd U_βTo be defeated Enter, three-phase given voltage U is obtained after modulation pattern_a、U_b、U_cDrive inverter and motor work.

2. vehicle-mounted internal permanent magnet synchronous motor control method as claimed in claim 1, it is characterised in that：

In step one,

Stator voltage equation is：

$\left\{\begin{array}{c}{u}_d=R_s\·i_d+L_d\·{\mathrm{pi}}_d-{\mathrm{\ω}}_e\·L_q\·i_q\\ u_q=R_s\·i_q+L_q\·{\mathrm{pi}}_q+{\mathrm{\ω}}_e\·L_d\·i_d+{\mathrm{\ω}}_e\·{\mathrm{\ψ}}_f\end{array}\right.---\left(1\right)$

Electromagnetic torque equation is：

$T_e=\frac{3}{2}{n}_p({\mathrm{\ψ}}_d{i}_q-{\mathrm{\ψ}}_q{i}_d)=\frac{3}{2}{n}_p\[{\mathrm{\ψ}}_f\·i_q+(L_d-L_q)\·i_d\·i_q\]---\left(2\right)$

In formula, R_s- stator resistance；P=d/dt-differential operator；i_d, i_q；L_d, L_q- d-axis and quadrature axis current and inductance；ω_e= n_p·ω_r—ω_eFor angular rate, n_pFor motor number of pole-pairs, ω_rFor mechanical angular speed；ψ_f- rotor permanent magnet and stator winding The magnetic linkage of interlinkage,

The torque equation of three-phase permanent magnet synchronous motor is as follows：

$\frac{J}{n_p}\·\frac{{\mathrm{d\ω}}_e}{dt}=T_e-T_L---\left(3\right).$

3. vehicle-mounted internal permanent magnet synchronous motor control method as claimed in claim 2, it is characterised in that：

In step 2,

It is speed error to make e, thenIt can be obtained by formula (3)：

$\begin{array}{c}\stackrel{\·}{e}=-{\stackrel{\·}{\mathrm{\ω}}}_e=-\frac{n_p}{J}(T_e-T_L)\\ \stackrel{\·\·}{e}=-{\stackrel{\·\·}{\mathrm{\ω}}}_e=-\frac{n_p}{J}\·{\stackrel{\·}{T}}_e\end{array}---\left(4\right)$

In formulaFor the rate of change of speed error,Lead, make for the second order of speed errorThen formula (4) can be arranged For：

$\left[\begin{array}{c}\stackrel{\·}{e}\\ \stackrel{\·\·}{e}\end{array}\right]=\left[\begin{array}{cc}0& 1\\ 0& 0\end{array}\right]\left[\begin{array}{c}e\\ \stackrel{\·}{e}\end{array}\right]-\left[\begin{array}{c}0\\ A\end{array}\right]U---\left(5\right)$

Designing sliding-mode surface isWherein c must is fulfilled for Hurwitz conditions, i.e. c ＞ 0, according to Li Yapu love stability Criterion, when V positive definites and with continuous first-order partial derivative, and V first-order partial derivative negative semidefinite, then it is stable, fixed Yi Liyapu love functions areIt is then guaranteeDesigning sliding formwork control ratio is：

$U=\frac{1}{A}\left(\mathrm{\α}\right|e\left|\mathrm{sgn}\right(s)+\mathrm{\β}\·s+c\stackrel{\·}{e})(\mathrm{\α}>0,\mathrm{\β}>0)---\left(6\right).$

4. vehicle-mounted internal permanent magnet synchronous motor control method as claimed in claim 3, it is characterised in that：

In step 3,

Foundation sets up torque capacity electric current than model with following formula (7) and formula (8),

$i_d=\frac{-{\mathrm{\ψ}}_f+\sqrt{{\mathrm{\ψ}}_f^2+4{(L_d-L_q)}^2{i}_q^2}}{2(L_d-L_q)}---\left(7\right)$

$4{(L_d-L_q)}^2{i}_q^4+\frac{4}{3}{\mathrm{\ψ}}_f{T}_e{i}_q-\frac{4}{9}{T}_e^2=0---\left(8\right).$

5. vehicle-mounted internal permanent magnet synchronous motor control method as claimed in claim 4, it is characterised in that：

In step 4, compareWithSize carry out operation phase of decision systems, when When, illustrate that now motor terminal voltage is less than voltage limit U_smax, using maximum torque per ampere control strategy；WhenWhen, illustrate that now motor terminal voltage reaches the limit values U_smax, using weak magnetic control strategy, whenWhen, redistribute i after taking the integrated adjuster output angle θ of its difference (between-pi/2 to 0)_q's Electric current, makes original i_qA part is used as i_dGo magnetic component, while itself component also reduces, realize weak magnetic speed-up.

6. vehicle-mounted internal permanent magnet synchronous motor control method as claimed in claim 5, it is characterised in that：

In step 5,

(b) electric voltage feed forward is decoupled

Obtained according to formula (1)

$\left\{\begin{array}{c}\frac{{\mathrm{di}}_d}{dt}=\frac{1}{L_d}\·(U_d+{\mathrm{\ω}}_e\·L_q\·i_q-R_s\·i_d)\\ \frac{{\mathrm{di}}_q}{dt}=\frac{1}{L_q}\·(U_q-{\mathrm{\ω}}_e\·L_d\·i_d-{\mathrm{\ω}}_e\·{\mathrm{\ψ}}_f-R_s\·i_q)\end{array}\right.---\left(9\right)$

In formula- direct-axis current rate of change；

- quadrature axis current rate of change,

By formula (9) it can be seen that i_dAnd i_qIntercouple, be a kind of Nonlinear system structure, it is impossible to individually controlled by d, q axle System, if L_dAnd L_qIt is larger, as this coupling of the rising of rotating speed can bring influence to electric current and torque response, for independent control I processed_dAnd i_q, the present invention is using the method for feedforward compensation to i_dAnd i_qDecoupled,

Defining offset voltage formula is

$\left\{\begin{array}{c}{U}_d^{\′}=U_d+{\mathrm{\ω}}_e\·L_d\·i_q\\ U_q^{\′}=U_q-{\mathrm{\ω}}_e\·L_d\·i_d-{\mathrm{\ω}}_e\·{\mathrm{\ψ}}_f\end{array}\right.---\left(10\right)$

In formula, U '_dDirect-axis voltage value after-compensation；

U′_qQuadrature-axis voltage value after-compensation,

Formula (10) is brought into formula (9) to obtain

$\left\{\begin{array}{c}\frac{{\mathrm{di}}_d}{dt}=\frac{1}{L_d}\·(U_d^{\′}-R_s\·i_d)\\ \frac{{\mathrm{di}}_q}{dt}=\frac{1}{L_q}\·(U_d^{\′}-R_s.i_q)\end{array}\right.---\left(11\right).$

7. vehicle-mounted internal permanent magnet synchronous motor control method as claimed in claim 6, it is characterised in that：

In step 6,

In real process, when motor operation is in the weak magnetic stage, given voltage is generally large, therefore occurs that ovennodulation shows As need to be to T when there is ovennodulation_x、T_yIt is adjusted, in order to further improve the utilization rate to inverter DC bus-bar voltage, Weak magnetic speed-up width is improved, the present invention carries out inversion to DC bus-bar voltage using a kind of SVPWM overmodulation method, specific as follows It is shown,

(a)T_x＞ T_yWhen

Work as T_x+T_y/ 2 ＞ T_sWhen, illustrate outside polygon, now T_x=T_s, T_y=0；

Work as T_x+T_y/ 2 ＜ T_sAnd T_x+T_y＞ T_sWhen illustrate ovennodulation, now T_x'=[T_x/(T_x+T_y)]·T_s, T_y'=[T_y/(T_x+ T_y)]·T_s；

Work as T_x+T_y/ 2 ＜ T_sAnd T_x+T_y＜ T_sWhen illustrate no ovennodulation, now T_x=T_x,T_y=T_y,

(b)T_x＜ T_yWhen

Work as T_x/2+T_y＞ T_sWhen, illustrate outside polygon, now T_x=0, T_y=T_s；

Work as T_x/2+T_y＜ T_sAnd T_x+T_y＞ T_sWhen illustrate ovennodulation, now T_x'=[T_x/(T_x+T_y)]·T_s, T_y'=[T_y/(T_x+ T_y)]·T_s；

Work as T_x/2+T_y＜ T_sAnd T_x+T_y＜ T_sWhen illustrate no ovennodulation, now T_x=T_x,T_y=T_y,

Wherein, T_xTo expect the component of voltage on the adjacent axle in voltage vector bottom；T_yTo expect on the adjacent axle in voltage vector top Component of voltage；T_sTo use the cycle.