阅读说明：本技术 一种电机输出转矩控制方法及系统 (Motor output torque control method and system ) 是由 高乐 孙楠楠 陈文淼 于 2020-06-29 设计创作，主要内容包括：本发明公开了一种电机输出转矩控制方法及系统,将获取到的上一时刻的电磁转矩输入至预先建立的可调模型,得到当前时刻的估计转子电角速度值,基于预先获取到的当前时刻的转子电角速度值和估计转子电角速度值的差值进行可调系数计算,得到可调系数,将可调系数进行转动惯量计算,得到辨识转动惯量,将辨识转动惯量、当前时刻的转子电角速度值和预先获取到的带通滤波器传递函数值进行主动阻尼运算,得到当前时刻的电磁转矩,并执行电机输出转矩的控制操作。通过上述方案,得到当前时刻的电磁转矩,即为抑制扭矩震动的电磁转矩,通过抑制扭矩震动的电磁转矩执行电机输出转矩的控制操作,降低车辆在行驶的过程中的电机转速震动,从而提升驾驶平顺性。(The invention discloses a motor output torque control method and a system, wherein the acquired electromagnetic torque at the previous moment is input into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment, an adjustable coefficient is calculated based on the difference value between the pre-acquired rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value to obtain an adjustable coefficient, the adjustable coefficient is calculated to obtain an identification rotational inertia, the rotor electrical angular velocity value at the current moment and a pre-acquired band-pass filter transfer function value are subjected to active damping operation to obtain the electromagnetic torque at the current moment, and the control operation of the motor output torque is executed. Through the scheme, the electromagnetic torque at the current moment is obtained, namely the electromagnetic torque for inhibiting the torque vibration, the control operation of the output torque of the motor is executed through the electromagnetic torque for inhibiting the torque vibration, the motor rotating speed vibration in the driving process of the vehicle is reduced, and therefore the driving smoothness is improved.)

1. A method of controlling output torque of a motor, the method comprising:

acquiring the electromagnetic torque at the previous moment;

performing difference calculation on the electromagnetic torque at the previous moment to obtain a difference value of the electromagnetic torques;

inputting the difference value of the electromagnetic torque into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment;

obtaining a difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment based on the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment, which are obtained in advance;

performing adjustable coefficient calculation on the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient;

performing rotational inertia calculation on the adjustable coefficient to obtain an identification rotational inertia;

performing active damping operation on the identification rotary inertia, the rotor electric angular velocity value at the current moment and a pre-obtained band-pass filter transfer function value to obtain the electromagnetic torque at the current moment;

and executing the control operation of the output torque of the motor based on the electromagnetic torque at the current moment.

2. The method of claim 1, wherein the inputting the difference of the electromagnetic torques into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at a current moment comprises:

inputting the difference value of the electromagnetic torque into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment;

wherein the pre-established adjustable model is represented as:

ω^P _e(k)＝2ω^M _e(k-1)-ω^M _e(k-2)+b_g(k)ΔT_e(k-1)

wherein, ω is^P _eFor estimating the value of the rotor electrical angular velocity, k is the time coefficient, ω^M _eAs the value of the electrical angular velocity of the rotor, b_gFor adjustable factor, T_eFor electromagnetic torque, Δ T_eAnd (k-1) is the difference of the electromagnetic torque in one sampling period.

3. The method according to claim 1, wherein the calculating an adjustable coefficient of the difference between the rotor electrical angular velocity value at the current time and the estimated rotor electrical angular velocity value at the current time to obtain an adjustable coefficient comprises:

performing adjustable coefficient calculation on the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient;

wherein the adjustable coefficient is represented as:

wherein, b_gK is the time coefficient, β is the adaptive gain coefficient, Δ T, for the adjustable coefficient_e(k-1) is the difference in electromagnetic torque over a sampling period, Δ ω_eAnd (k-1) the difference value of the rotor electric angular velocity value and the estimated rotor electric angular velocity value.

4. The method of claim 1, wherein calculating the adjustable coefficients to obtain an identified moment of inertia comprises:

performing rotational inertia calculation on the adjustable coefficient in a sampling period to obtain an identification rotational inertia;

wherein the identifying moment of inertia is expressed as:

wherein, b_gFor the adjustable coefficient, k is the time coefficient, T_sIn order to be the sampling period of time,is the identified moment of inertia.

5. The method according to claim 1, wherein the pre-obtaining of the values of the band pass filter transfer functions comprises:

acquiring the resonance frequency of the band-pass filter;

inputting the resonance frequency of the band-pass filter into a band-pass filter transfer function model to obtain a band-pass filter transfer function value;

wherein the band pass filter transfer function model is represented as:

wherein G is_BPFTransferring a function value, omega, for said band-pass filter₀And S is the resonance frequency of the band-pass filter, S is a differential operator, and Q is a quality factor.

6. The method according to claim 1, wherein the performing active damping operation on the identified moment of inertia, the current-time rotor electrical angular velocity value and the pre-obtained band-pass filter transfer function value to obtain the current-time electromagnetic torque comprises:

acquiring the resonance frequency of the band-pass filter;

inputting the resonance frequency of the band-pass filter into a band-pass filter transfer function model to obtain a band-pass filter transfer function value;

wherein the band pass filter transfer function model is represented as:

wherein G is_BPFTransferring a function value, omega, for said band-pass filter₀The resonance frequency of the band-pass filter is S, a differential operator is S, and Q is a quality factor;

obtaining a high-frequency jitter component based on the rotor electrical angular velocity value at the current moment and the band-pass filter transfer function value;

and obtaining the electromagnetic torque at the current moment based on the high-frequency jitter component and the identification moment of inertia.

7. An electric machine output torque control system, the system comprising:

a first acquisition unit configured to acquire an electromagnetic torque at a previous time;

the first calculation unit is used for carrying out difference calculation on the electromagnetic torque at the previous moment to obtain a difference value of the electromagnetic torque;

the second obtaining unit is used for inputting the difference value into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment;

a third obtaining unit, configured to obtain a difference between the current-time rotor electrical angular velocity value and the current-time estimated rotor electrical angular velocity value based on a pre-obtained current-time rotor electrical angular velocity value and the current-time estimated rotor electrical angular velocity value;

the second calculation unit is used for calculating an adjustable coefficient according to the difference between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient;

the third calculation unit is used for calculating the rotational inertia of the adjustable coefficient to obtain the identification rotational inertia;

the fourth calculation unit is used for performing active damping operation on the identification rotary inertia, the rotor electric angular velocity value at the current moment and a pre-acquired band-pass filter transfer function value to obtain the electromagnetic torque at the current moment;

and the execution unit is used for executing the control operation of the output torque of the motor based on the electromagnetic torque at the current moment.

8. The system of claim 7, wherein the second obtaining unit is specifically configured to:

inputting the difference value into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment; wherein the pre-established adjustable model is represented as:

ω^P _e(k)＝2ω^M _e(k-1)-ω^M _e(k-2)+b_g(k)ΔT_e(k-1)

wherein, ω is^P _eFor estimating the value of the rotor electrical angular velocity, k is the time coefficient, ω^M _eAs the value of the electrical angular velocity of the rotor, b_gFor adjustable factor, T_eFor electromagnetic torque, Δ T_eAnd (k-1) is the difference of the electromagnetic torque in one sampling period.

9. The system according to claim 7, wherein the second computing unit is specifically configured to:

performing adjustable coefficient calculation on the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient; wherein the adjustable coefficient is represented as:

wherein, b_gFor the adjustable coefficients, k is the time of day coefficient, β is the adaptive gain coefficient, Δ T_e(k-1) is the difference in electromagnetic torque over a sampling period, Δ ω_eAnd (k-1) the difference value of the rotor electric angular velocity value and the estimated rotor electric angular velocity value.

10. The system according to claim 7, wherein the third computing unit is specifically configured to:

performing rotational inertia calculation on the adjustable coefficient in a sampling period to obtain an identification rotational inertia;

wherein the identifying moment of inertia is expressed as:

wherein, b_gFor the adjustable coefficient, k is the time coefficient, T_sIn order to be the sampling period of time,is the identified moment of inertia.

Technical Field

The invention relates to the technical field of motor torque, in particular to a motor output torque control method and system.

Background

With the increasing importance of energy conservation and environmental protection, the use of electric automobiles is gradually increased.

Complicated power coupling relations exist among all power transmission parts of the electric automobile, and the electric automobile transmission system has special characteristics of rigid connection and no damping, so that the friction phenomenon occurs among gear gaps of the electric automobile transmission system, and the motor rotating speed of the electric automobile fluctuates.

Frequent motor speed fluctuation and friction between gear gaps cause the torque vibration of a transmission system of the electric automobile, so that the electric automobile can vibrate in the driving process, and the driving smoothness of the electric automobile is poor.

Disclosure of Invention

In view of the above, the present invention discloses a method and a system for controlling an output torque of a motor, which obtains an electromagnetic torque at the current moment, that is, an electromagnetic torque for suppressing torque vibration, and performs a control operation of the output torque of the motor by the electromagnetic torque for suppressing torque vibration, so as to reduce the vibration of the motor speed during the driving of a vehicle, thereby improving the driving smoothness.

In order to achieve the purpose, the technical scheme is as follows:

the invention discloses a motor output torque control method in a first aspect, which comprises the following steps:

acquiring the electromagnetic torque at the previous moment;

performing difference calculation on the electromagnetic torque at the previous moment to obtain a difference value of the electromagnetic torques;

inputting the difference value of the electromagnetic torque into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment;

obtaining a difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment based on the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment, which are obtained in advance;

performing adjustable coefficient calculation on the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient;

performing rotational inertia calculation on the adjustable coefficient to obtain an identification rotational inertia;

performing active damping operation on the identification rotary inertia, the rotor electric angular velocity value at the current moment and a pre-obtained band-pass filter transfer function value to obtain the electromagnetic torque at the current moment;

and executing the control operation of the output torque of the motor based on the electromagnetic torque at the current moment.

Preferably, the inputting the difference value of the electromagnetic torques into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment includes:

inputting the difference value of the electromagnetic torque into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment;

wherein the pre-established adjustable model is represented as:

ω^P _e(k)＝2ω^M _e(k-1)-ω^M _e(k-2)+b_g(k)ΔT_e(k-1)

wherein, ω is^P _eFor estimating the value of the rotor electrical angular velocity, k is the time coefficient, ω^M _eAs the value of the electrical angular velocity of the rotor, b_gFor adjustable factor, T_eFor electromagnetic torque, Δ T_eAnd (k-1) is the difference of the electromagnetic torque in one sampling period.

Preferably, the calculating an adjustable coefficient of the difference between the current rotor electrical angular velocity value and the current estimated rotor electrical angular velocity value to obtain an adjustable coefficient includes:

performing adjustable coefficient calculation on the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient;

wherein the adjustable coefficient is represented as:

wherein, b_gK is the time coefficient, β is the adaptive gain coefficient, Δ T, for the adjustable coefficient_e(k-1) is the difference in electromagnetic torque over a sampling period, Δ ω_eAnd (k-1) the difference value of the rotor electric angular velocity value and the estimated rotor electric angular velocity value.

Preferably, the calculating the moment of inertia of the adjustable coefficient to obtain the identification moment of inertia includes:

performing rotational inertia calculation on the adjustable coefficient in a sampling period to obtain an identification rotational inertia;

wherein the identifying moment of inertia is expressed as:

wherein, b_gFor the adjustable coefficient, k is the time coefficient, T_sIn order to be the sampling period of time,is the identified moment of inertia.

Preferably, the process of obtaining the transfer function value of the band pass filter in advance includes:

acquiring the resonance frequency of the band-pass filter;

inputting the resonance frequency of the band-pass filter into a band-pass filter transfer function model to obtain a band-pass filter transfer function value;

wherein the band pass filter transfer function model is represented as:

wherein G is_BPFTransferring a function value, omega, for said band-pass filter₀And S is the resonance frequency of the band-pass filter, S is a differential operator, and Q is a quality factor.

Preferably, the performing active damping operation on the identified moment of inertia, the current-time rotor electrical angular velocity value, and a pre-obtained band-pass filter transfer function value to obtain the current-time electromagnetic torque includes:

acquiring the resonance frequency of the band-pass filter;

inputting the resonance frequency of the band-pass filter into a band-pass filter transfer function model to obtain a band-pass filter transfer function value;

wherein the band pass filter transfer function model is represented as:

wherein G is_BPFTransferring a function value, omega, for said band-pass filter₀The resonance frequency of the band-pass filter is S, a differential operator is S, and Q is a quality factor;

obtaining a high-frequency jitter component based on the rotor electrical angular velocity value at the current moment and the band-pass filter transfer function value;

and obtaining the electromagnetic torque at the current moment based on the high-frequency jitter component and the identification moment of inertia.

In a second aspect of the present invention, there is disclosed a motor output torque control system, the system comprising:

a first acquisition unit configured to acquire an electromagnetic torque at a previous time;

the first calculation unit is used for carrying out difference calculation on the electromagnetic torque at the previous moment to obtain a difference value of the electromagnetic torque;

the second obtaining unit is used for inputting the difference value into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment;

a third obtaining unit, configured to obtain a difference between the current-time rotor electrical angular velocity value and the current-time estimated rotor electrical angular velocity value based on a pre-obtained current-time rotor electrical angular velocity value and the current-time estimated rotor electrical angular velocity value;

the second calculation unit is used for calculating an adjustable coefficient according to the difference between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient;

the third calculation unit is used for calculating the rotational inertia of the adjustable coefficient to obtain the identification rotational inertia;

the fourth calculation unit is used for performing active damping operation on the identification rotary inertia, the rotor electric angular velocity value at the current moment and a pre-acquired band-pass filter transfer function value to obtain the electromagnetic torque at the current moment;

and the execution unit is used for executing the control operation of the output torque of the motor based on the electromagnetic torque at the current moment.

Preferably, the second obtaining unit is specifically configured to:

inputting the difference value into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment; wherein the pre-established adjustable model is represented as:

ω^P _e(k)＝2ω^M _e(k-1)-ω^M _e(k-2)+b_g(k)ΔT_e(k-1)

wherein, ω is^P _eFor estimating the value of the rotor electrical angular velocity, k is the time coefficient, ω^M _eAs the value of the electrical angular velocity of the rotor, b_gFor adjustable factor, T_eFor electromagnetic torque, Δ T_eAnd (k-1) is the difference of the electromagnetic torque in one sampling period.

Preferably, the second calculating unit is specifically configured to:

performing adjustable coefficient calculation on the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient; wherein the adjustable coefficient is represented as:

wherein, b_gFor the adjustable coefficients, k is the time coefficient, β is adaptiveGain factor, Δ T_e(k-1) is the difference in electromagnetic torque over a sampling period, Δ ω_eAnd (k-1) the difference value of the rotor electric angular velocity value and the estimated rotor electric angular velocity value.

Preferably, the third calculating unit is specifically configured to:

performing rotational inertia calculation on the adjustable coefficient in a sampling period to obtain an identification rotational inertia;

wherein the identifying moment of inertia is expressed as:

wherein, b_gFor the adjustable coefficient, k is the time coefficient, T_sIn order to be the sampling period of time,

is the identified moment of inertia.

According to the technical scheme, the obtained electromagnetic torque at the previous moment is input into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment, an adjustable coefficient is calculated based on a difference value between the pre-obtained rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value to obtain an adjustable coefficient, the adjustable coefficient is subjected to rotational inertia calculation to obtain an identification rotational inertia, the rotor electrical angular velocity value at the current moment and a pre-obtained band-pass filter transfer function value are subjected to active damping operation to obtain the electromagnetic torque at the current moment, and control operation of the output torque of the motor is executed. Through the scheme, the electromagnetic torque at the current moment is obtained, namely the electromagnetic torque for inhibiting the torque vibration, the control operation of the output torque of the motor is executed through the electromagnetic torque for inhibiting the torque vibration, the motor rotating speed vibration in the driving process of the vehicle is reduced, and therefore the driving smoothness is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a schematic flow chart illustrating a method for controlling output torque of a motor according to an embodiment of the present invention;

FIG. 2 is a flowchart illustrating a method for obtaining an identified moment of inertia according to an embodiment of the present disclosure;

FIG. 3 is a block diagram of an active damping control process disclosed in an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a motor output torque control system according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Known from the background art, in the prior art, frequent fluctuation of the motor rotation speed and friction between gear gaps cause torque vibration of a transmission system of an electric automobile, so that the electric automobile can vibrate in the driving process, and the driving smoothness of the electric automobile is poor.

In order to solve the problem, the invention discloses a motor output torque control method and a system, the acquired electromagnetic torque at the previous moment is input into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment, an adjustable coefficient is calculated based on the difference value between the pre-acquired rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value to obtain an adjustable coefficient, the adjustable coefficient is subjected to rotational inertia calculation to obtain an identification rotational inertia, the rotor electrical angular velocity value at the current moment and a pre-acquired band-pass filter transfer function value are subjected to active damping operation to obtain the electromagnetic torque at the current moment, and the control operation of the motor output torque is executed. Through the scheme, the electromagnetic torque at the current moment is obtained, namely the electromagnetic torque for inhibiting the torque vibration, the control operation of the output torque of the motor is executed through the electromagnetic torque for inhibiting the torque vibration, the motor rotating speed vibration in the driving process of the vehicle is reduced, and therefore the driving smoothness is improved. The specific implementation is specifically illustrated by the following examples.

As shown in fig. 1, a schematic flow chart of a method for controlling an output torque of a motor according to an embodiment of the present invention is disclosed, the method for controlling an output torque of a motor is applied to a motor controller, and the method for controlling an output torque of a motor mainly includes:

s101: and acquiring the electromagnetic torque at the last moment.

The electromagnetic torque is a rotation torque formed on the rotor by interaction of magnetic fluxes of poles of a rotating magnetic field of the motor and rotor current.

And performing correlation processing on the acquired electromagnetic torque at the previous moment to obtain the electromagnetic torque at the current moment. And a process of performing correlation processing by using the electromagnetic torque at the previous time to obtain the electromagnetic torque at the current time, as shown in S102-S108.

S102: and carrying out difference calculation on the electromagnetic torque at the previous moment to obtain the difference value of the electromagnetic torque.

The difference in electromagnetic torque is expressed as:

ΔT_e(k-1)＝T_e(k-1)-T_e(k-2) (1)

wherein, Delta T_e(k-1) is the difference in electromagnetic torque over a sampling period, k is the time coefficient, T_eIs an electromagnetic torque.

S103: and inputting the difference value of the electromagnetic torque into a pre-established adjustable model to obtain the estimated rotor electrical angular velocity value at the current moment.

The adjustable model is shown in formula (2).

Wherein, ω is^P _eFor estimating the value of the rotor electrical angular velocity, k is the time coefficient, ω^M _eAs the value of the electrical angular velocity of the rotor, b_gFor adjustable factor, T_eFor electromagnetic torque, Δ T_eAnd (k-1) is the difference of the electromagnetic torque in one sampling period.

The calculation formula of the adjustable coefficient is shown in formula (3).

b_g＝T_s/J (3)

Wherein J is moment of inertia, T_sIs the sampling period.

The process of the pre-established adjustable model is as follows:

based on the moment of inertia, the rotor electrical angular velocity value, the electromagnetic torque and the load torque, a vehicle driveline model is determined, as shown in equation (4).

Wherein the content of the first and second substances,

for differential calculation, T_LIs the load torque.

The formula (4) is discretized and simplified to obtain the formula (5).

In a sampling period, the variation of the load torque is approximately kept unchanged, and as can be seen from equation (5), the load torque can be cancelled out after the difference is made, so as to obtain equation (6).

ω_e(k)＝2ω_e(k-1)-ω_e(k-2)+b_gΔT_e(k-1) (6)

And (4) obtaining an adjustable model based on the formula (6), wherein the adjustable model is shown in the formula (2).

S104: and obtaining the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment based on the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment, which are obtained in advance.

And carrying out differential calculation on the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment, which are obtained in advance, so as to obtain the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment.

Wherein, the difference between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment is represented as:

wherein, the delta omega (k-1) is the difference value of the rotor electric angular velocity value and the estimated rotor electric angular velocity value,

in order to be the value of the electrical angular velocity of the rotor,to estimate the rotor electrical angular velocity value.

S105: and calculating an adjustable coefficient according to the difference between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient.

The tunable coefficients are expressed as:

wherein, b_gK is the time coefficient, β is the adaptive gain coefficient, Δ T, for the adjustable coefficient_e(k-1) is the difference in electromagnetic torque over a sampling period, Δ ω_eAnd (k-1) the difference value of the rotor electric angular velocity value and the estimated rotor electric angular velocity value.

S106: and performing rotational inertia calculation on the adjustable coefficient to obtain the identification rotational inertia.

Based on equation (3), the identified moment of inertia can be obtained, and the identified moment of inertia is shown as equation (9).

Wherein the content of the first and second substances,to identify the moment of inertia.

To facilitate understanding of the process of obtaining the identified moment of inertia, fig. 2 shows a flowchart of obtaining the identified moment of inertia, and in particular, an implementation process of obtaining the identified moment of inertia, as shown in a1-a 5.

A1: and carrying out difference calculation on the obtained electromagnetic torque at the previous moment to obtain the difference value of the electromagnetic torque.

A2: and inputting the difference value of the electromagnetic torque into the adjustable model to obtain the estimated rotor electrical angular velocity value at the current moment.

A3: and obtaining the difference value between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment based on the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment, which are obtained in advance.

A4: and calculating an adjustable coefficient according to the difference between the rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient.

Wherein the adjustable model is adjusted by the adjustable coefficient.

A5: and performing rotational inertia calculation on the adjustable coefficient to obtain the identification rotational inertia.

T in FIG. 2_eIn order to be an electromagnetic torque,in order to be the value of the electrical angular velocity of the rotor,

for estimating the value of the rotor electrical angular velocity, Δ ω_eAs the difference between the rotor electrical angular velocity value and the estimated rotor electrical angular velocity value, b_gIn order to be an adjustable coefficient,for identifying the moment of inertia, "-" is a difference calculation between the rotor electric angular velocity value and the estimated rotor electric angular velocity value, and "+" is a sum calculation between the rotor electric angular velocity value and the estimated rotor electric angular velocity value.

S107: and performing active damping operation on the identified rotary inertia, the rotor electric angular velocity value at the current moment and the pre-acquired band-pass filter transfer function value to obtain the electromagnetic torque at the current moment.

The process involving the band pass filter transfer function values acquired in advance in execution S107 is as shown in B1-B2.

B1: the resonant frequency of the band-pass filter is obtained.

B2: and inputting the resonance frequency of the band-pass filter into the band-pass filter transfer function model to obtain the transfer function value of the band-pass filter.

The band-pass filter transfer function model is shown in formula (10).

Wherein G is_BPFFor band-pass filter transfer function value, omega₀Is the resonance frequency of the band-pass filter, S is the differential operator and Q is the quality factor.

In step S107, the process of performing active damping operation on the identified moment of inertia, the current-time rotor electrical angular velocity value, and the pre-obtained band-pass filter transfer function value to obtain the current-time electromagnetic torque is performed, as shown in steps C1-C4.

C1: the resonant frequency of the band-pass filter is obtained.

C2: and inputting the resonance frequency of the band-pass filter into the band-pass filter transfer function model to obtain the transfer function value of the band-pass filter.

C3: and obtaining a high-frequency jitter component based on the rotor electrical angular velocity value at the current moment and the band-pass filter transfer function value.

The high-frequency jitter component is a parameter influencing the driving smoothness of the whole vehicle.

C4: and obtaining the electromagnetic torque at the current moment based on the high-frequency jitter component and the identification moment of inertia.

For the convenience of understanding the above process of performing the active damping operation on the moment of inertia at the present time, the pre-acquired angular velocity of the rotor at the present time, and the pre-acquired transfer function value of the band pass filter, as shown in fig. 3, a structural diagram of the active damping control process is shown.

In FIG. 3,. omega._eAs value of rotor electrical angular velocity, ω_{e_hf}For high frequency jitter components, T_{e_Activedamping}For active damping of torque, T_{e_Vehicle}The motor controller controls the final output torque of the motor,for identifying the moment of inertia, S is a differential operator, S is equivalent to

Is a differential calculation.

Firstly, inputting the angular speed of a rotor to a band-pass filter transfer function to obtain a high-frequency jitter component, then, carrying out differential calculation on the high-frequency jitter component and an identification moment of inertia to obtain an active damping torque, and finally, obtaining a final output torque of a motor controller controlled motor output motor based on the active damping torque and an electromagnetic torque.

S108: based on the electromagnetic torque at the present time, a control operation of the motor output torque is performed.

The electromagnetic torque at the current moment is obtained through active damping operation, the control operation of the output torque of the motor is executed, and the motor rotating speed vibration of the vehicle in the driving process is reduced, so that the driving smoothness is improved.

The embodiment of the invention discloses a motor output torque control method, which comprises the steps of inputting the obtained electromagnetic torque at the previous moment into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment, carrying out adjustable coefficient calculation based on the difference value between the pre-obtained rotor electrical angular velocity value at the current moment and the estimated rotor electrical angular velocity value to obtain an adjustable coefficient, carrying out rotational inertia calculation on the adjustable coefficient to obtain an identification rotational inertia, carrying out active damping operation on the identification rotational inertia, the rotor electrical angular velocity value at the current moment and a pre-obtained band-pass filter transfer function value to obtain the electromagnetic torque at the current moment, and executing control operation of the motor output torque. Through the scheme, the electromagnetic torque at the current moment is obtained, namely the electromagnetic torque for inhibiting the torque vibration, the control operation of the output torque of the motor is executed through the electromagnetic torque for inhibiting the torque vibration, the motor rotating speed vibration in the driving process of the vehicle is reduced, and therefore the driving smoothness is improved.

Based on the method for controlling the output torque of the motor disclosed by the embodiment, the embodiment of the invention also correspondingly discloses a system for controlling the output torque of the motor, and as shown in fig. 4, the system for controlling the output torque of the motor comprises:

a first obtaining unit 401, configured to obtain the electromagnetic torque at the last time.

The electromagnetic torque is a rotation torque formed on the rotor by interaction of magnetic fluxes of poles of a rotating magnetic field of the motor and rotor current.

A first calculating unit 402, configured to perform difference calculation on the electromagnetic torques at the previous time to obtain a difference value of the electromagnetic torques.

Wherein the difference in electromagnetic torque is expressed as:

ΔT_e(k-1)＝T_e(k-1)-T_e(k-2)

wherein, Delta T_e(k-1) is the difference in electromagnetic torque over a sampling period, k is the time coefficient, T_eIs an electromagnetic torque.

The second obtaining unit 403 is configured to input the difference between the electromagnetic torques to a pre-established adjustable model, so as to obtain an estimated rotor electrical angular velocity value at the current time.

Further, the second obtaining unit 403 is specifically configured to input the difference between the electromagnetic torques to a pre-established adjustable model, so as to obtain an estimated rotor electrical angular velocity value at the current time; wherein the pre-established adjustable model is represented as:

ω^P _e(k)＝2ω^M _e(k-1)-ω^M _e(k-2)+b_g(k)ΔT_e(k-1)

wherein, ω is^P _eFor estimating the value of the rotor electrical angular velocity, k is the time coefficient, ω^M _eAs the value of the electrical angular velocity of the rotor, b_gFor adjustable factor, T_eFor electromagnetic torque, Δ T_eAnd (k-1) is the difference of the electromagnetic torque in one sampling period.

A third obtaining unit 404, configured to obtain a difference between the current-time rotor electrical angular velocity value and the current-time estimated rotor electrical angular velocity value based on a pre-obtained current-time rotor electrical angular velocity value and the current-time estimated rotor electrical angular velocity value.

The second calculating unit 405 is configured to perform adjustable coefficient calculation on a difference between the current-time rotor electrical angular velocity value and the current-time estimated rotor electrical angular velocity value to obtain an adjustable coefficient.

Further, the second calculating unit 405 is specifically configured to perform adjustable coefficient calculation on a difference between the current rotor electrical angular velocity value and the current estimated rotor electrical angular velocity value to obtain an adjustable coefficient; wherein the adjustable coefficient is expressed as:

wherein, b_gK is the time coefficient, β is the adaptive gain coefficient, Δ T, for the adjustable coefficient_e(k-1) is the difference in electromagnetic torque over a sampling period, Δ ω_eAnd (k-1) the difference value of the rotor electric angular velocity value and the estimated rotor electric angular velocity value.

And a third calculating unit 406, configured to perform a rotational inertia calculation on the adjustable coefficient to obtain an identification rotational inertia.

Further, the third calculating unit 406 is specifically configured to perform a rotational inertia calculation on the adjustable coefficient within the sampling period to obtain an identification rotational inertia; wherein, the identification moment of inertia is expressed as:

wherein, b_gIs an adjustable coefficient, k is a time coefficient, T_sIn order to be the sampling period of time,to identify the moment of inertia.

And a fourth calculating unit 407, configured to perform active damping operation on the identification rotational inertia, the rotational inertia obtained in advance, the rotor electrical angular velocity value at the current time, and the band-pass filter transfer function value obtained in advance, so as to obtain the electromagnetic torque at the current time.

Further, the fourth calculating unit 407 for the process of obtaining the transfer function value of the bandpass filter in advance includes a first obtaining module and a second obtaining module.

The first acquisition module is used for acquiring the resonance frequency of the band-pass filter.

And the second acquisition module is used for inputting the resonance frequency of the band-pass filter into the band-pass filter transfer function model to obtain a band-pass filter transfer function value.

Wherein the band-pass filter transfer function model is represented as:

wherein G is_BPFFor band-pass filter transfer function value, omega₀Is the resonance frequency of the band-pass filter, S is the differential operator and Q is the quality factor.

Further, the fourth calculating unit 407 includes: the device comprises a third acquisition module, a fourth acquisition module, a fifth acquisition module and a sixth acquisition module.

And the third acquisition module is used for acquiring the resonance frequency of the band-pass filter.

And the fourth acquisition module is used for inputting the resonance frequency of the band-pass filter into the band-pass filter transfer function model to obtain a band-pass filter transfer function value.

Wherein the band-pass filter transfer function model is represented as:

wherein G is_BPFFor band-pass filter transfer function value, omega₀Is the resonance frequency of the band-pass filter, S is the differential operator and Q is the quality factor.

And the fifth acquisition module is used for obtaining a high-frequency jitter component based on the rotor electrical angular velocity value at the current moment and the band-pass filter transfer function value.

And the sixth acquisition module is used for acquiring the electromagnetic torque at the current moment based on the high-frequency jitter component and the identification moment of inertia.

And an execution unit 408 for executing a control operation of the motor output torque based on the electromagnetic torque at the present time.

The electromagnetic torque at the current moment is obtained through active damping operation, the control operation of the output torque of the motor is executed, and the motor rotating speed vibration of the vehicle in the driving process is reduced, so that the driving smoothness is improved.

The embodiment of the invention discloses a motor output torque control system, which is characterized in that the acquired electromagnetic torque at the previous moment is input into a pre-established adjustable model to obtain an estimated rotor electrical angular velocity value at the current moment, an adjustable coefficient is calculated based on the difference value between the estimated rotor electrical angular velocity value and the pre-acquired rotor electrical angular velocity value at the current moment to obtain an adjustable coefficient, the adjustable coefficient is calculated to obtain an identification rotational inertia, the rotor electrical angular velocity value at the current moment and a pre-acquired band-pass filter transfer function value are subjected to active damping operation to obtain the electromagnetic torque at the current moment, and the control operation of the motor output torque is executed. Through the system, the electromagnetic torque at the current moment is obtained, namely the electromagnetic torque for inhibiting torque vibration, the control operation of the output torque of the motor is executed through the electromagnetic torque for inhibiting the torque vibration, the motor rotating speed vibration in the driving process of the vehicle is reduced, and therefore the driving smoothness is improved.

While, for purposes of simplicity of explanation, the foregoing method embodiments have been described as a series of acts or combination of acts, it will be appreciated by those skilled in the art that the present invention is not limited by the illustrated ordering of acts, as some steps may occur in other orders or concurrently with other steps in accordance with the invention. Further, those skilled in the art should also appreciate that the embodiments described in the specification are preferred embodiments and that the acts and modules referred to are not necessarily required by the invention.

It should be noted that, in the present specification, the embodiments are all described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments may be referred to each other. For the system-class embodiment, since it is basically similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The steps in the method of each embodiment of the invention can be sequentially adjusted, combined and deleted according to actual needs.

Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.