阅读说明：本技术 一种电机转速控制方法及系统 (Motor rotating speed control method and system ) 是由 高乐 孙楠楠 陈文淼 赵强 于 2020-06-29 设计创作，主要内容包括：本发明公开了一种电机转速控制方法及系统,获取电机输出电磁转矩和上一时刻的电机转速,将预设的给定转速和上一时刻的电机转速进行积分运算,得到给定电磁转矩,将给定电磁转矩、预设的给定转速、预设的截止频率和电机输出电磁转矩输入至预先建立的电机转速模型,得到当前时刻的电机转速,基于当前时刻的电机转速,执行电机转速控制操作。通过上述方案,基于预先建立的电机转速模型,得到当前时刻的电机转速,即为优化后的电机转速,基于该优化后的电机转速执行电机转速控制操作。此外,通过增强电机转速控制系统阻尼,使得当前时刻的电机转速跟随预设的给定转速,防止出现转速超调现象和振荡现象,从而有利于电机转速控制系统的稳定性。(The invention discloses a motor rotating speed control method and a system, which are used for obtaining motor output electromagnetic torque and motor rotating speed at the previous moment, carrying out integral operation on preset given rotating speed and the motor rotating speed at the previous moment to obtain given electromagnetic torque, inputting the given electromagnetic torque, the preset given rotating speed, preset cut-off frequency and the motor output electromagnetic torque to a preset motor rotating speed model to obtain the motor rotating speed at the current moment, and executing motor rotating speed control operation based on the motor rotating speed at the current moment. According to the scheme, the motor rotating speed at the current moment is obtained based on the pre-established motor rotating speed model, namely the optimized motor rotating speed, and the motor rotating speed control operation is executed based on the optimized motor rotating speed. In addition, the damping of the motor rotating speed control system is enhanced, so that the rotating speed of the motor at the current moment follows the preset given rotating speed, the phenomenon of rotating speed overshoot and the phenomenon of oscillation are prevented, and the stability of the motor rotating speed control system is facilitated.)

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

acquiring the output electromagnetic torque of the motor and the rotating speed of the motor at the previous moment;

performing integral operation on a preset given rotating speed and the rotating speed of the motor at the previous moment to obtain a given electromagnetic torque;

inputting the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque to a pre-established motor rotating speed model to obtain the motor rotating speed at the current moment;

and executing motor rotating speed control operation based on the motor rotating speed at the current moment.

2. The method according to claim 1, wherein the integrating the preset given rotation speed and the motor rotation speed at the previous moment to obtain the given electromagnetic torque comprises:

calculating the difference between a preset given rotating speed and the motor rotating speed at the previous moment to obtain the difference between the preset given rotating speed and the motor rotating speed at the previous moment;

and performing integral operation based on the difference value to obtain the given electromagnetic torque.

3. The method of claim 1, wherein inputting the given electromagnetic torque, the preset given rotation speed, the preset cut-off frequency and the motor output electromagnetic torque into a pre-established motor rotation speed model to obtain the motor rotation speed at the current moment comprises:

respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

inputting the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque into a pre-established motor rotating speed model for processing, and outputting the motor rotating speed at the current moment;

wherein the pre-established motor speed model is expressed as:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,for said given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

4. The method of claim 1, wherein the pre-modeling of the motor speed comprises:

constructing a motor motion equation model based on the motor output electromagnetic torque, the preset motor rotational inertia and the motor rotating speed at the current moment;

respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

constructing a motor control equation model based on the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given rotating speed and the given electromagnetic torque;

determining an initial motor rotation speed model based on the motor motion equation model and the motor control equation model;

determining a motor rotation speed model based on the initial motor rotation speed model, the integral coefficient, the active damping coefficient and the anti-saturation coefficient;

wherein the motor speed model is represented as:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,for said given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

5. A motor speed control system, the system comprising:

the first acquisition unit is used for acquiring the output electromagnetic torque of the motor and the motor rotating speed at the previous moment;

the calculating unit is used for carrying out integral operation on a preset given rotating speed and the rotating speed of the motor at the previous moment to obtain a given electromagnetic torque;

the second acquisition unit is used for inputting the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque into a motor rotating speed model which is established in advance to obtain the motor rotating speed at the current moment;

and the execution unit is used for executing the motor rotating speed control operation based on the motor rotating speed at the current moment.

6. The system of claim 5, wherein the computing unit comprises:

the calculation module is used for calculating the difference between the preset given rotating speed and the motor rotating speed at the previous moment to obtain the difference between the preset given rotating speed and the motor rotating speed at the previous moment;

and the first acquisition module is used for carrying out integral operation on the basis of the difference value to obtain the given electromagnetic torque.

7. The system of claim 5, wherein the second obtaining unit comprises:

the second acquisition module is used for respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

a third obtaining module, configured to input the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given electromagnetic torque, the preset given rotation speed, the preset cut-off frequency, and the motor output electromagnetic torque to a pre-established motor rotation speed model for processing, and output a motor rotation speed at a current moment;

wherein the pre-established motor speed model is expressed as:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,for said given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

8. The system according to claim 5, wherein the second obtaining unit of the process of pre-establishing the motor rotation speed model includes:

the first building module is used for building a motor motion equation model based on the motor output electromagnetic torque, the preset motor moment of inertia and the motor rotating speed at the current moment;

the fourth acquisition module is used for respectively acquiring an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

the second construction module is used for constructing a motor control equation model based on the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given rotating speed and the given electromagnetic torque;

the first determination module is used for determining an initial motor rotating speed model based on the motor motion equation model and the motor control equation model;

a second determination module, configured to determine a motor rotation speed model based on the initial motor rotation speed model, the integral coefficient, the active damping coefficient, and the anti-saturation coefficient;

wherein the representation of the motor speed model is:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,

Technical Field

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

Background

A motor speed control system of the electric vehicle is controlled by a motor controller. In general, a PI regulator is used for controlling the rotation speed of the motor controller.

The PI regulator is a linear controller, forms a control deviation according to a given value and an actual output value, linearly combines the proportion and the integral of the control deviation to form a control quantity, and controls the rotating speed of the motor.

Because the control algorithm of the PI regulator is simple, although the conventional rotating speed requirement can be met, in the process of controlling the rotating speed, the rotating speed overshoot phenomenon that the actual rotating speed value exceeds the given rotating speed value and the oscillation phenomenon that the actual rotating speed value changes up and down around the given rotating speed value easily occur, and the stability of the motor rotating speed control system is not facilitated.

Disclosure of Invention

In view of the above, the invention discloses a method and a system for controlling the rotating speed of a motor, which enable the rotating speed of the motor at the current moment to follow a preset given rotating speed by enhancing the damping of a motor rotating speed control system, so as to prevent the phenomenon of rotating speed overshoot and oscillation, thereby being beneficial to the stability of the motor rotating speed control system.

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

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

acquiring the output electromagnetic torque of the motor and the rotating speed of the motor at the previous moment;

performing integral operation on a preset given rotating speed and the rotating speed of the motor at the previous moment to obtain a given electromagnetic torque;

inputting the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque to a pre-established motor rotating speed model to obtain the motor rotating speed at the current moment;

and executing motor rotating speed control operation based on the motor rotating speed at the current moment.

Preferably, the integrating operation of the preset given rotation speed and the motor rotation speed at the previous moment to obtain the given electromagnetic torque includes:

calculating the difference between a preset given rotating speed and the motor rotating speed at the previous moment to obtain the difference between the preset given rotating speed and the motor rotating speed at the previous moment;

and performing integral operation based on the difference value to obtain the given electromagnetic torque.

Preferably, the inputting the given electromagnetic torque, the preset given rotation speed, the preset cut-off frequency and the motor output electromagnetic torque to a pre-established motor rotation speed model to obtain the motor rotation speed at the current moment includes:

respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

inputting the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque into a pre-established motor rotating speed model for processing, and outputting the motor rotating speed at the current moment;

wherein the pre-established motor speed model is expressed as:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,for said given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

Preferably, the process of pre-establishing the motor rotation speed model includes:

constructing a motor motion equation model based on the motor output electromagnetic torque, the preset motor rotational inertia and the motor rotating speed at the current moment;

respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

constructing a motor control equation model based on the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given rotating speed and the given electromagnetic torque;

determining an initial motor rotation speed model based on the motor motion equation model and the motor control equation model;

determining a motor rotation speed model based on the initial motor rotation speed model, the integral coefficient, the active damping coefficient and the anti-saturation coefficient;

wherein the motor speed model is represented as:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,

for said given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

In a second aspect of the present invention, a system for controlling a rotational speed of a motor is disclosed, the system comprising:

the first acquisition unit is used for acquiring the output electromagnetic torque of the motor and the motor rotating speed at the previous moment;

the calculating unit is used for carrying out integral operation on a preset given rotating speed and the rotating speed of the motor at the previous moment to obtain a given electromagnetic torque;

the second acquisition unit is used for inputting the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque into a motor rotating speed model which is established in advance to obtain the motor rotating speed at the current moment;

and the execution unit is used for executing the motor rotating speed control operation based on the motor rotating speed at the current moment.

Preferably, the calculation unit includes:

the calculation module is used for calculating the difference between the preset given rotating speed and the motor rotating speed at the previous moment to obtain the difference between the preset given rotating speed and the motor rotating speed at the previous moment;

and the first acquisition module is used for carrying out integral operation on the basis of the difference value to obtain the given electromagnetic torque.

Preferably, the second obtaining unit includes:

the second acquisition module is used for respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

a third obtaining module, configured to input the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given electromagnetic torque, the preset given rotation speed, the preset cut-off frequency, and the motor output electromagnetic torque to a pre-established motor rotation speed model for processing, and output a motor rotation speed at a current moment;

wherein the pre-established motor speed model is expressed as:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,

for said given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

Preferably, the second obtaining unit of the process of establishing the motor rotation speed model in advance includes:

the first building module is used for building a motor motion equation model based on the motor output electromagnetic torque, the preset motor moment of inertia and the motor rotating speed at the current moment;

the fourth acquisition module is used for respectively acquiring an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency;

the second construction module is used for constructing a motor control equation model based on the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given rotating speed and the given electromagnetic torque;

the first determination module is used for determining an initial motor rotating speed model based on the motor motion equation model and the motor control equation model;

a second determination module, configured to determine a motor rotation speed model based on the initial motor rotation speed model, the integral coefficient, the active damping coefficient, and the anti-saturation coefficient;

wherein the representation of the motor speed model is:

where s is a differential operator, ω_cFor said cut-off frequency, n^*For the given speed of rotation in question,for said given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

According to the technical scheme, the motor output electromagnetic torque and the motor rotating speed at the previous moment are obtained, the preset given rotating speed and the motor rotating speed at the previous moment are subjected to integral operation to obtain the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque are input to a pre-established motor rotating speed model to obtain the motor rotating speed at the current moment, and the motor rotating speed control operation is executed based on the motor rotating speed at the current moment. According to the scheme, the motor rotating speed at the current moment is obtained based on the pre-established motor rotating speed model, namely the optimized motor rotating speed, and the motor rotating speed control operation is executed based on the optimized motor rotating speed. In addition, the damping of the motor rotating speed control system is enhanced, so that the rotating speed of the motor at the current moment follows the preset given rotating speed, the phenomenon of rotating speed overshoot and the phenomenon of oscillation are prevented, and the stability of the motor rotating speed control system is facilitated.

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 of a method for controlling a rotational speed of a motor according to an embodiment of the present invention;

FIG. 2 is a logic diagram of a motor speed control system with active damping and anti-saturation according to an embodiment of the present invention;

fig. 3 is a schematic flow chart of a motor rotation speed 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.

As can be seen from the background art, in the prior art, because the control algorithm of the PI regulator is simple, although the conventional requirement for the rotation speed can be met, in the process of controlling the rotation speed, a rotation speed overshoot phenomenon in which the actual rotation speed exceeds the given rotation speed value and an oscillation phenomenon in which the actual rotation speed changes up and down around the given rotation speed value easily occur, which are not favorable for the stability of the motor rotation speed control system.

In order to solve the problem, the invention discloses a motor rotating speed control method and a system, which are used for obtaining the output electromagnetic torque of a motor and the rotating speed of the motor at the previous moment, carrying out integral operation on the preset given rotating speed and the rotating speed of the motor at the previous moment to obtain the given electromagnetic torque, inputting the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the output electromagnetic torque of the motor to a preset motor rotating speed model to obtain the rotating speed of the motor at the current moment, and executing the motor rotating speed control operation based on the rotating speed of the motor at the current moment. According to the scheme, the motor rotating speed at the current moment is obtained based on the pre-established motor rotating speed model, namely the optimized motor rotating speed, and the motor rotating speed control operation is executed based on the optimized motor rotating speed. In addition, the damping of the motor rotating speed control system is enhanced, so that the rotating speed of the motor at the current moment follows the preset given rotating speed, the phenomenon of rotating speed overshoot and the phenomenon of oscillation are prevented, and the stability of the motor rotating speed control system is facilitated. The specific implementation is specifically illustrated by the following examples.

As shown in fig. 1, which is a schematic flow chart of a motor speed control method disclosed in an embodiment of the present invention, the motor speed control method is applied to a motor controller, and the motor speed control method mainly includes the following steps:

s101: and acquiring the output electromagnetic torque of the motor and the motor rotating speed at the previous moment.

Wherein, the magnetic flux of each pole of the rotating magnetic field of the motor interacts with the rotor current to form a rotating torque on the rotor.

S102: and performing integral operation on the preset given rotating speed and the rotating speed of the motor at the previous moment to obtain the given electromagnetic torque.

The process of integrating the preset given rotation speed and the motor rotation speed at the previous moment to obtain the given electromagnetic torque is executed in step S102, as shown in a1-a 2:

a1: and performing difference calculation on the preset given rotating speed and the motor rotating speed at the previous moment to obtain a difference value of the preset given rotating speed and the motor rotating speed at the previous moment.

A2: and performing integral operation based on the difference value to obtain the given electromagnetic torque.

And the static error of the motor rotating speed control system can be ensured by adopting integral operation, and the control precision of the motor rotating speed control system is favorably improved.

S103: and inputting the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque into a motor rotating speed model established in advance to obtain the motor rotating speed at the current moment.

And respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency.

The preset cut-off frequency is determined by the dynamic response requirement of the motor speed control system.

The calculation formula of the integral coefficient, the active damping coefficient and the anti-saturation coefficient is shown as formula (1).

Wherein, K_iIs the integral coefficient, K_dFor active damping coefficient, K_aIs the antisaturation coefficient, omega_cIs the cut-off frequency.

The integral coefficient is used for reducing the static difference, the active damping coefficient is used for improving the damping of the motor control system, and the anti-saturation coefficient is used for improving the speed of exiting the saturation state.

When the given electromagnetic torque is larger than the electromagnetic torque output by the motor, the rotating speed regulator of the motor rotating speed control system enters a saturated state, and the speed of exiting the saturated state is increased through the anti-saturation coefficient, so that the rotating speed regulator rapidly exits the saturated state.

In order to ensure the stability of the motor rotating speed control system, the change trend of the motor rotating speed can be predicted by carrying out active damping operation on the motor rotating speed at the last moment, the damping degree of the system is increased, and the rotating speed overshoot and oscillation of the motor rotating speed control system are reduced.

The rotating speed overshoot refers to the fact that the actual rotating speed value of the motor exceeds a given rotating speed value.

Oscillation means that the actual motor speed value varies up and down around a preset given speed value.

And inputting the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque into a preset motor rotating speed model for processing, and outputting the motor rotating speed at the current moment.

The motor rotating speed model is established in advance as shown in formula (2).

Where s is a differential operator, ω_cTo cut-off frequency, n^*For a given preset speed of rotation, the speed of rotation is,for a given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

The process of establishing a motor rotating speed model in advance is shown as B1-B5:

b1: and constructing a motor motion equation model based on the motor output electromagnetic torque, the preset motor rotational inertia and the motor rotating speed at the current moment.

And (4) calculating a formula of the motor motion equation model, as shown in formula (3).

Wherein, T_eAnd outputting electromagnetic torque for the motor, wherein J is the rotational inertia of the motor, pi is the circumferential rate, s is a differential operator, and n is the motor rotating speed at the current moment.

B2: and respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency.

B3: and constructing a motor control equation model based on the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given rotating speed and the given electromagnetic torque.

And (4) calculating a formula of the motor control equation model, as shown in formula (4).

Wherein the content of the first and second substances,for a given electromagnetic torque, T_eFor the output of electromagnetic torque of the machine, s is a differential operator, n^*Is a preset given rotating speed, n is the rotating speed of the motor at the current moment, K_iIs the integral coefficient, K_dFor active damping coefficient, K_aThe coefficient of anti-saturation.

B4: and determining an initial motor rotating speed model based on the motor motion equation model and the motor control equation model.

Formula (5) can be obtained by the arrangement of formula (3) and formula (4), and formula (5) is a calculation formula of the initial motor rotation speed model.

Wherein the content of the first and second substances,for a given electromagnetic torque, T_eFor the output of electromagnetic torque of the machine, s is a differential operator, n^*Is a preset given rotating speed, n is the rotating speed of the motor at the current moment, K_iIs the integral coefficient, K_dFor active damping coefficient, K_aAnd the coefficient of saturation resistance is shown, pi is the circumferential rate, and J is the rotational inertia of the motor.

B5: and determining the motor rotating speed model based on the initial motor rotating speed model, the integral coefficient, the active damping coefficient and the anti-saturation coefficient.

The formula of the motor rotation speed model is shown in formula (6).

Where s is a differential operator, ω_cTo cut-off frequency, n^*For a given preset speed of rotation, the speed of rotation is,

for a given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

The motor rotating speed at the current moment tracks a given rotating speed by taking cut-off frequency as a second-order low-pass filtering track, and the parameters of the regulator of the motor rotating speed tracking system comprise an integral coefficient, an active damping coefficient and an anti-saturation coefficient which are calculated by the set cut-off frequency of a rotating speed control system and load rotational inertia.

Because the motor rotating speed at the current moment tracks the preset given rotating speed according to the second-order closed-loop system, and the conventional rotating speed control system tracks the preset given rotating speed according to the first-order closed-loop system, the second-order closed-loop system has better steady-state precision and dynamic response than the first-order closed-loop system, so that the scheme has better bandwidth frequency, the capability of tracking the given rotating speed by the motor rotating speed at the current moment is stronger, and the output attenuation speed of the motor rotating speed control system is higher for input signals higher than the bandwidth frequency.

S104: based on the motor speed at the present time, a motor speed control operation is performed.

When gear shifting operation is needed in driving a vehicle, accurate rotating speed control is needed, and the accurate rotating speed of the motor obtained through the motor rotating speed model is used for executing the motor rotating speed control to finish the gear shifting operation.

The motor rotating speed at the current moment is obtained through the motor rotating speed model, the motor rotating speed control operation is executed based on the motor rotating speed at the current moment, the rotating speed overshoot phenomenon and the oscillation phenomenon cannot occur, and therefore the stability of a motor rotating speed control system is facilitated.

In order to facilitate understanding of the process of motor speed control, and considering that the mechanical time constant of the motor speed control system is much larger than the electrical time constant of the current loop, the electrical time constants of the current loop and the motor inverter are ignored, and as shown in fig. 2, a logic diagram of the motor speed control system with an active damping function and an anti-saturation link is shown.

In FIG. 2, n^*For a given preset speed of rotation, the speed of rotation is,

for a given electromagnetic torque, the electromagnetic torque is,T_efor the output of electromagnetic torque of the motor, s is a differential operator, K_iIs the integral coefficient, K_dFor active damping coefficient, K_aFor the antisaturation coefficient, π is the circumferential ratio, T_LAnd J is the load torque, the moment of inertia of the motor is J, and n is the rotating speed of the motor at the current moment.

The difference value of the preset given rotating speed and the motor rotating speed at the previous moment is subjected to an integral link Ki/s to obtain a given torque, the torque output capacity of the controller is limited by a performance curve, when the given torque output by the rotating speed regulator is larger than the electromagnetic torque output by the motor, the rotating speed regulator enters saturation, and the rotating speed regulator exits the saturation state through an anti-saturation link Ka/s. And the motor outputs electromagnetic torque to act on the motor, the motor rotating speed at the current moment is obtained according to the motion equation model of the motor, and the motor rotating speed control operation is executed according to the rotating speed at the current moment.

The embodiment of the invention discloses a motor rotating speed control method and a motor rotating speed control system, which are used for obtaining the output electromagnetic torque of a motor and the rotating speed of the motor at the previous moment, carrying out integral operation on the preset given rotating speed and the rotating speed of the motor at the previous moment to obtain the given electromagnetic torque, inputting the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the output electromagnetic torque of the motor to a preset motor rotating speed model to obtain the rotating speed of the motor at the current moment, and executing the motor rotating speed control operation based on the rotating speed of the motor at the current moment. According to the scheme, the motor rotating speed at the current moment is obtained based on the pre-established motor rotating speed model, namely the optimized motor rotating speed, and the motor rotating speed control operation is executed based on the optimized motor rotating speed. In addition, the damping of the motor rotating speed control system is enhanced, so that the rotating speed of the motor at the current moment follows the preset given rotating speed, the phenomenon of rotating speed overshoot and the phenomenon of oscillation are prevented, and the stability of the motor rotating speed control system is facilitated.

Based on the method for controlling the rotating speed of the motor disclosed in the above embodiment, the embodiment of the present invention also correspondingly discloses a system for controlling the rotating speed of the motor, as shown in fig. 3, the system for controlling the rotating speed of the motor includes a first obtaining unit 301, a calculating unit 302, a second obtaining unit 303 and an executing unit 304.

A first obtaining unit 301, configured to obtain an output electromagnetic torque of the motor and a motor rotation speed at a previous time.

Wherein, the magnetic flux of each pole of the rotating magnetic field of the motor interacts with the rotor current to form a rotating torque on the rotor.

And the calculating unit 302 is configured to perform integral operation on a preset given rotation speed and a rotation speed of the motor at a previous moment to obtain a given electromagnetic torque.

Further, the calculating unit 302 includes a calculating module and a first obtaining module.

And the calculating module is used for calculating the difference between the preset given rotating speed and the motor rotating speed at the previous moment to obtain the difference between the motor rotating speed at the previous moment and the preset given rotating speed.

And the first acquisition module is used for carrying out integral operation on the basis of the difference value to obtain the given electromagnetic torque.

The second obtaining unit 303 is configured to input the given electromagnetic torque, the preset given rotation speed, the preset cut-off frequency, and the motor output electromagnetic torque to a pre-established motor rotation speed model, so as to obtain the motor rotation speed at the current moment.

Further, the second obtaining unit 303 includes a second obtaining module and a third obtaining module.

And the second acquisition module is used for respectively obtaining an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency.

The preset cut-off frequency is determined by the dynamic response requirement of the motor speed control system.

The integral coefficient is used for reducing the static difference, the active damping coefficient is used for improving the damping of the motor control system, and the anti-saturation coefficient is used for improving the speed of exiting the saturation state.

And the third acquisition module is used for inputting the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given electromagnetic torque, the preset given rotating speed, the preset cut-off frequency and the motor output electromagnetic torque into a pre-established motor rotating speed model for processing, and outputting the motor rotating speed at the current moment.

The pre-established motor rotating speed model is expressed as follows:

where s is a differential operator, ω_cTo cut-off frequency, n^*For a given rotational speed of the motor vehicle,for a given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

Further, the second obtaining unit 303 further includes a first constructing module, a fourth obtaining module, a second constructing module, a first determining module, and a second determining module.

The first building module is used for building a motor motion equation model based on the output electromagnetic torque of the motor, the preset motor moment of inertia and the motor rotating speed at the current moment.

And the fourth acquisition module is used for respectively acquiring an integral coefficient, an active damping coefficient and an anti-saturation coefficient based on a preset cut-off frequency.

And the second construction module is used for constructing a motor control equation model based on the integral coefficient, the active damping coefficient, the anti-saturation coefficient, the given rotating speed and the given electromagnetic torque.

The first determining module is used for determining an initial motor rotating speed model based on the motor motion equation model and the motor control equation model.

And the second determination module is used for determining the motor rotating speed model based on the initial motor rotating speed model, the integral coefficient, the active damping coefficient and the anti-saturation coefficient.

Wherein the representation of the motor speed model is as follows:

where s is a differential operator, ω_cTo cut-off frequency, n^*Preset isGiven the speed of rotation of the motor, the motor is,

for a given electromagnetic torque, T_eAnd outputting electromagnetic torque for the motor, wherein n is the motor rotating speed at the current moment.

And an execution unit 304, configured to execute a motor rotation speed control operation based on the motor rotation speed at the current time.

When gear shifting operation is needed in driving a vehicle, accurate rotating speed control is needed, and the accurate rotating speed of the motor obtained through the motor rotating speed model is used for executing the motor rotating speed control to finish the gear shifting operation.

The motor rotating speed at the current moment is obtained through the motor rotating speed model, the motor rotating speed control operation is executed based on the motor rotating speed at the current moment, the rotating speed overshoot phenomenon and the oscillation phenomenon cannot occur, and therefore the stability of a motor rotating speed control system is facilitated.

The invention discloses a motor rotating speed control system, which is used for acquiring motor output electromagnetic torque and motor rotating speed at the previous moment, performing integral operation on preset given rotating speed and the motor rotating speed at the previous moment to obtain given electromagnetic torque, inputting the given electromagnetic torque, the preset given rotating speed, preset cut-off frequency and the motor output electromagnetic torque to a preset motor rotating speed model to obtain the motor rotating speed at the current moment, and executing motor rotating speed control operation based on the motor rotating speed at the current moment. Through the system, the motor rotating speed at the current moment is obtained based on the pre-established motor rotating speed model, namely the optimized motor rotating speed, and the motor rotating speed control operation is executed based on the optimized motor rotating speed. In addition, the damping of the motor rotating speed control system is enhanced, so that the rotating speed of the motor at the current moment follows the preset given rotating speed, the phenomenon of rotating speed overshoot and the phenomenon of oscillation are prevented, and the stability of the motor rotating speed control system is facilitated.

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.