阅读说明：本技术 基于降维观测器的电机调速控制方法 (Motor speed regulation control method based on dimension reduction observer ) 是由 黄建 杜林奎 张新华 洋婷 王贯 宋志翌 王天乙 李浩男 徐方洁 于 2021-06-17 设计创作，主要内容包括：本发明提供了一种基于降维观测器的电机调速控制方法,该基于降维观测器的电机调速控制方法包括：构建电流环,获取电流环PI控制器比例系数和电流环积分系数；根据电流环构建速度环,获取速度环比例系数及速度环积分系数；构建降维转矩观测器,获取负载转矩和转矩观测器系数,将负载转矩乘以转矩观测器系数后反馈至电流环的输入以完成基于降维观测器的电机调速控制。应用本发明的技术方案,能够解决现有技术中传统的永磁同步电机控制方法无法满足高精度和强抗扰的调速控制要求的技术问题。(The invention provides a motor speed regulation control method based on a dimension reduction observer, which comprises the following steps: constructing a current loop, and acquiring a proportional coefficient and a current loop integral coefficient of a current loop PI controller; constructing a speed loop according to the current loop, and acquiring a speed loop proportion coefficient and a speed loop integral coefficient; and constructing a dimension reduction torque observer, acquiring a load torque and a torque observer coefficient, multiplying the load torque by the torque observer coefficient, and feeding back the result to the input of a current loop to finish the motor speed regulation control based on the dimension reduction observer. By applying the technical scheme of the invention, the technical problem that the traditional permanent magnet synchronous motor control method in the prior art cannot meet the speed regulation control requirements of high precision and strong interference resistance can be solved.)

1. A motor speed regulation control method based on a dimension reduction observer is characterized by comprising the following steps: constructing a current loop, and acquiring a proportional coefficient and a current loop integral coefficient of a current loop PI controller; constructing a speed loop according to the current loop, and acquiring a speed loop proportion coefficient and a speed loop integral coefficient; and constructing a dimension reduction torque observer, acquiring a load torque and a torque observer coefficient, multiplying the load torque by the torque observer coefficient, and feeding back the multiplied load torque to the input of the current loop to finish the motor speed regulation control based on the dimension reduction observer.

2. The method of claim 1, wherein the open-loop transfer function of the current loop isWherein R is_sIs the motor stator resistance, L_sFor the stator inductance of the machine, K_uFor PWM amplifier gain, k_iiIs the current loop integral coefficient, k_piIs the proportional coefficient of the current loop PI controller, and s is a differential operator.

3. The method for controlling the speed regulation of the motor based on the reduced-dimension observer according to claim 1 or 2, wherein the closed-loop transfer function of the current loop isWherein, a₁＝R_s/L_s，a₂＝K_uK_fi/L_s，K_fiIs the current feedback coefficient.

4. The method of claim 3, wherein the method is based on a₁＝R_s/L_s、a₂＝K_uK_fi/L_sAndobtaining a current loop PI controller proportional coefficient and a current loop integral coefficient, wherein omega_nIs the free oscillation frequency of the system, epsilon is the damping ratio, omega_bIs the current loop bandwidth.

5. The method of claim 4, wherein the transfer function of the speed loop regulator isWherein k is_pvIs a velocity loop scale factor, k_ivIs a velocity loop integral coefficient, K_p＝K_iv，T₁＝K_pv/K_iv。

6. The method of claim 5, wherein the open-loop transfer function of the speed loop isWherein J is the moment of inertia of the rotating part, K_tIs the motor moment coefficient, K is the stability margin, T₂Is the time constant of the equivalent reduced order of the current loop.

7. The method of claim 6, wherein the method is based on the method of controlling the speed of the motor based on the dimension-reducing observerObtaining the time constant T after the equivalent reduction of the current loop by reducing the order of the second-order transfer function₂According to T₂、ω₁＝1/T₁、K＝ω₁ω_c、T₁＝K_pv/K_ivAndcan obtain the proportional coefficient and integral coefficient of speed loop, where omega_cIs the velocity loop cut-off frequency, gamma_maxFor the extreme phase angle margin of the speed loop system,h is the intermediate frequency bandwidth.

8. The dimension-reducing observer-based motor speed regulation control method according to any one of claims 1 to 7, characterized in that the dimension-reducing observer-based motor speed regulation control method is based onConstructing a reduced-dimension torque observer, wherein ω_rIs the motor speed, T_eIs the electromagnetic torque, T, of a permanent magnet synchronous machine_e＝C_TφI_q，C_TIs the torque constant of the motor, phi is the main flux chain of the motor, I_qIs torque current, k₁And k₂As a torque observer coefficient, T_lThe load torque of the motor is observed and obtained by a dimension reduction torque observer.

9. The dimension-reducing observer-based motor speed regulation control method according to claim 8, wherein the dimension-reducing observer-based motor speed regulation control method is according to s²- (α + β) s + α β ═ 0 andobtaining a torque observer coefficient k₁And k₂Wherein alpha and beta are poles, the poles alpha and beta are estimated according to the current loop cutoff frequency and the speed loop cutoff frequency, and f is the friction coefficient of the motor.

Technical Field

The invention relates to the technical field of permanent magnet synchronous motor speed regulation control, in particular to a motor speed regulation control method based on a dimensionality reduction observer.

Background

Liquid engines are being developed in both the multi-electric and full-electric directions as core components of aerospace vehicles. The oil supply system is a core part of an engine system, and the performance of the oil supply system is particularly important for the efficient operation of the engine. The engine applied to the high-performance aircraft has the characteristics of high efficiency, quick response and the like, and the fuel flow has the most direct influence on the working state of the engine, so that the high-performance engine puts forward severe requirements on an oil supply system such as high control precision, strong interference resistance and the like. As a core component for regulating the fuel flow of an oil supply system of a multi-electric engine, the speed regulation performance of an electric fuel pump has a crucial influence on the oil supply system. The electric fuel pump speed regulating system adopting the traditional control method cannot meet the development requirement of the high-performance engine at the present stage.

The electric fuel pump drives the pump head to rotate through the motor to achieve fuel flow control, the electric fuel pump serves as a core power component of the electric fuel pump system, the permanent magnet synchronous motor is widely applied to the fields of aerospace and the like due to the advantages of high power density, high efficiency, high precision, low torque pulsation and the like, and the driving control performance of the permanent magnet synchronous motor is directly related to the dynamic quality of an electric fuel pump speed regulating system. Aiming at the design requirements of a high-performance electric fuel pump speed regulating system, a permanent magnet synchronous motor excitation decoupling vector control strategy based on a traditional PID algorithm cannot meet the speed regulating control requirements of high precision and strong interference resistance, so that the search for a permanent magnet synchronous motor speed regulating control strategy with high precision and strong interference resistance is very important.

Disclosure of Invention

The invention provides a motor speed regulation control method based on a dimensionality reduction observer, which can solve the technical problem that the traditional permanent magnet synchronous motor control method in the prior art cannot meet the speed regulation control requirements of high precision and strong interference resistance.

The invention provides a motor speed regulation control method based on a dimension reduction observer, which comprises the following steps: constructing a current loop, and acquiring a proportional coefficient and a current loop integral coefficient of a current loop PI controller; constructing a speed loop according to the current loop, and acquiring a speed loop proportion coefficient and a speed loop integral coefficient; and constructing a dimension reduction torque observer, acquiring a load torque and a torque observer coefficient, multiplying the load torque by the torque observer coefficient, and feeding back the result to the input of a current loop to finish the motor speed regulation control based on the dimension reduction observer.

Further, the open loop transfer function of the current loop isWherein R is_sIs the motor stator resistance, L_sFor the stator inductance of the machine, K_uFor PWM amplifier gain, k_iiIs the current loop integral coefficient, k_piIs the proportional coefficient of the current loop PI controller, and s is a differential operator.

Further, the closed loop transfer function of the current loop isWherein, a₁＝R_s/L_s，a₂＝K_uK_fi/L_s，K_fiIs the current feedback coefficient.

Further, a motor speed regulation control method based on a dimension reduction observer is according to a₁＝R_s/L_s、a₂＝K_uK_fi/L_sAndobtaining a current loop PI controller proportional coefficient and a current loop integral coefficient, wherein omega_nIs the free oscillation frequency of the system, epsilon is the damping ratio, omega_bIs the current loop bandwidth.

Further, the speed loop regulator transfer function isWherein k is_pvIs a velocity loop scale factor, k_ivIs a velocity loop integral coefficient, K_p＝K_iv，T₁＝K_pv/K_iv。

Further, the open loop transfer function of the velocity loop isWherein J is the moment of inertia of the rotating part, K_tIs the motor moment coefficient, K is the stability margin, T₂Is the time constant of the equivalent reduced order of the current loop.

Further, a motor speed regulation control method based on a dimension reduction observer is based onObtaining the time constant T after the equivalent reduction of the current loop by reducing the order of the second-order transfer function₂According to T₂、ω₁＝1/T₁、K＝ω₁ω_c、T₁＝K_pv/K_ivAndcan obtain the proportional coefficient and integral coefficient of speed loop, where omega_cIs the velocity loop cut-off frequency, gamma_maxThe phase angle margin extreme value of the speed loop system is shown, and h is the intermediate frequency bandwidth.

Further, a motor speed regulation control method based on a dimension reduction observer is based onConstructing a reduced-dimension torque observer, wherein ω_rIs the motor speed, T_eIs the electromagnetic torque, T, of a permanent magnet synchronous machine_e＝C_TφI_q，C_TIs the torque constant of the motor, phi is the main flux chain of the motor, I_qIs torque current, k₁And k₂As a torque observer coefficient, T_lThe load torque of the motor is observed and obtained by a dimension reduction torque observer.

Further, a motor speed regulation control method based on a dimension reduction observer is based on s²- (α + β) s + α β ═ 0 andobtaining a torque observer coefficient k₁And k₂Wherein alpha and beta are poles, the poles alpha and beta are estimated according to the current loop cutoff frequency and the speed loop cutoff frequency, and f is the friction coefficient of the motor.

By constructing an observation module based on the load torque and the load rotating speed of the reduced-dimension observer and a permanent magnet synchronous motor vector control module based on a current loop and a rotating speed loop double closed loop of observation torque compensation, the speed regulation control of the high-precision and strong-disturbance-resistance permanent magnet synchronous motor can be realized, the dynamic characteristic, the control precision and the disturbance resistance of the electric fuel pump system are improved, and the effects of improving the dynamic control quality and the comprehensive energy efficiency of an engine are further achieved. Compared with the prior art, the technical scheme of the invention can solve the technical problem that the traditional permanent magnet synchronous motor control method in the prior art cannot meet the speed regulation control requirements of high precision and strong interference resistance.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. It is obvious that the drawings in the following description are only some embodiments of the invention, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

FIG. 1 is a flow chart of a method for controlling the speed of a motor based on a reduced-dimension observer according to an embodiment of the present invention;

FIG. 2 is a schematic diagram illustrating a structure of a dimension reduction observer according to an embodiment of the present invention;

FIG. 3 is a control block diagram of a dimension reduction observer provided according to an embodiment of the present invention;

FIG. 4 illustrates a simplified mathematical model schematic of a permanent magnet synchronous machine provided in accordance with a specific embodiment of the present invention;

FIG. 5 is a schematic diagram illustrating a block diagram of a current loop provided in accordance with a specific embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating a block diagram of a speed loop provided in accordance with a specific embodiment of the present invention;

FIG. 7 illustrates an open-loop logarithmic frequency characteristic of a velocity loop provided in accordance with a specific embodiment of the present invention;

FIG. 8 is a diagram illustrating a dimension-reduced observer-based motor speed control scheme according to an embodiment of the present invention;

fig. 9 shows a comparison of starting speeds of 2000rpm of the motor provided according to an embodiment of the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. 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. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. 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.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

The relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise. Meanwhile, it should be understood that the sizes of the respective portions shown in the drawings are not drawn in an actual proportional relationship for the convenience of description. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

As shown in fig. 1, according to an embodiment of the present invention, a method for controlling a speed of a motor based on a dimension reduction observer is provided, where the method for controlling a speed of a motor based on a dimension reduction observer includes: constructing a current loop, and acquiring a proportional coefficient and a current loop integral coefficient of a current loop PI controller; constructing a speed loop according to the current loop, and acquiring a speed loop proportion coefficient and a speed loop integral coefficient; and constructing a dimension reduction torque observer, acquiring a load torque and a torque observer coefficient, multiplying the load torque by the torque observer coefficient, and feeding back the multiplied load torque to a current loop for input so as to finish the motor speed regulation control based on the dimension reduction observer.

By applying the configuration mode, the motor speed regulation control method based on the dimension reduction observer is provided, and can realize the speed regulation control of the high-precision and strong-disturbance-resistance permanent magnet synchronous motor by constructing the observation module based on the load torque and the load rotating speed of the dimension reduction observer and the permanent magnet synchronous motor vector control module based on the current loop and rotating speed loop double closed loop of the observation torque compensation, thereby improving the dynamic characteristic, the control precision and the disturbance resistance of the electric fuel pump system and further achieving the effect of improving the dynamic control quality and the comprehensive energy efficiency of an engine. Compared with the prior art, the technical scheme of the invention can solve the technical problem that the traditional permanent magnet synchronous motor control method in the prior art cannot meet the speed regulation control requirements of high precision and strong interference resistance.

In the art, the mechanical characteristic equation of a permanent magnet synchronous motor is

Wherein, T_eIs the electromagnetic torque, T, of a permanent magnet synchronous machine_e＝C_TφI_q，C_TIs the torque constant of the motor, phi is the main flux chain of the motor, I_qFor torque current, T_lIs the load torque of the motor, J is the moment of inertia of the rotating part, ω_rThe motor speed is f, the friction coefficient of the motor is f, and the time is t.

According to the mechanical characteristic equation of the motor, the electromagnetic torque generated by the flux linkage and the torque current is the driving torque of the motor rotor, the load torque is the braking torque, and the electromagnetic torque overcomes the load torque and the friction torque to enable the motor rotor to generate acceleration and deceleration processes. Generally, the load torque of the motor is an unknown quantity and changes with the change of the external load, and the change of the external load cannot be considered when the motor is controlled, so the control aging presents hysteresis. Particularly, for a permanent magnet synchronous motor for a fuel oil speed regulation system, the load of the permanent magnet synchronous motor is influenced by various factors such as the height, the speed, the external air pressure and the temperature of an aircraft, the change rule is very complex and is difficult to linearly estimate, the speed regulation system can only passively respond to the change of the load torque, when the load torque changes, if the electromagnetic torque keeps unchanged, the mechanical characteristic equation shows that the rotating speed of the motor fluctuates, and the fluctuation size is directly related to the load change rate, so that the rotating speed control accuracy of the motor is difficult to maintain under the condition of load change (namely disturbance of an external load).

In order to reduce the influence of motor load disturbance on the motor rotating speed control precision and improve the load disturbance resistance of the motor so as to improve the rotating speed control precision of the motor, the load torque of the motor needs to be observed, and an observed value is fed back to a motor electromagnetic torque control loop, so that the influence of load torque change on the rotating speed precision is reduced. Based on the mechanical characteristic equation of the motor, the invention provides a motor speed regulation control method based on a dimension reduction observer.

Let the estimated system be an n-dimensional linear constancy system with the equation of state

Where A, B and C are the real matrices of order n × n, n × r, and m × n, respectively, and assuming (A, C) is observable, C is the full rank matrix. x is the actual system output, y is the output lead observed value, and u is the system input.

Order toOptionally (n-m) x n order constant matrix R is selected such that the n x n order matrix Q is nonsingular, thenWherein the content of the first and second substances,andrespectively m x m, m x (n-m), (n-m) x m and (n-m) x (n-m) order matrices, B₁And B₂Respectively m x r and (n-m) x r order matrices, I_mIs an m-order identity matrix. From the above, it can be known that the linear nonsingular transformation is performedNext, the estimated system algebra is equivalent to the following system

Wherein the content of the first and second substances,andrespectively m and (n-m) dimension states. As can be seen from the above equation, for the transformed stateIts state is divided intoNamely the output y of the system, can be directly utilized, and the (n-m) dimension division state is required to be reconstructedTherefore, only one (n-m) -dimensional state observer is needed to achieve the reconstruction purpose.

Can be derived from the above formulaOrder toCan be written as

Wherein the content of the first and second substances,for the (n-m) order subsystem,in the form of a matrix of states,is an output matrix.

The construction method of the dimensionality reduction observer is obtained through the previous derivation and comprises the following steps: constructing an (n-m) order simulation system according to the deduced state equation of the (n-m) order subsystem; the output of the analog system is subtracted from the output of the observer, and the difference is passed through a negative feedback matrix K_eIs fed back toThe purpose of the end is to make the difference value of the two outputs approach to 0 as soon as possible, thereby achieving the purpose ofApproach toThe purpose of (1). The construction of a reduced dimension state observer structure according to the above is shown in fig. 2.

From this, the state equation of the dimension reduction state observer can be derived as

Considering that the sampling rate of the control algorithm is sufficiently high, the load torque may be considered to be a constant value, i.e. dT, during the sampling period_lAnd/dt is 0. And then the state equation of the permanent magnet synchronous motor load torque observer can be derived according to the mechanical characteristic equation of the permanent magnet synchronous motor and the state equation of the dimension reduction state observer

Wherein the content of the first and second substances,u＝T_e，the state equation of the permanent magnet synchronous motor load torque observer can be written as

The characteristic equation of the permanent magnet synchronous motor dimension reduction load torque observer is

Wherein s is a differential operator, and I is an electromagnetic torque current value.

An appropriate K can be determined by the arrangement of the poles_eTo makeApproach toThe speed of (2) meets certain requirements. Assuming the expected poles are α and β, the target characteristic equation is

s²-(α+β)s+αβ＝0 (9)

The characteristic equation of the above formula and the permanent magnet synchronous motor dimension reduction load torque observer can be obtained

Wherein k is₁And k₂The coefficient of friction f is neglected as the coefficient of the torque observer, and can be obtained by the above formula

A control block diagram of a dimension-reduced load torque observer constructed according to the above formula is shown in FIG. 3, where K_tIs the electromagnetic torque coefficient of the permanent magnet synchronous motor. The system rotating speed and the q-axis current are used as the input of an observer, and the rotating speed and the load torque can be observed through calculation.

The load torque observed by the dimensionality reduction torque observer is multiplied by a certain coefficient to be used as compensation quantity of current loop input and participate in control, so that when an external load changes, the motor control system changes the current loop input through the torque compensation control quantity, and the effect of inhibiting load change is achieved.

As can be seen from the above derivation, in the present invention, in order to implement the motor speed regulation control based on the reduced-dimension observer, a current loop is first constructed, and a current loop PI controller proportional coefficient and a current loop integral coefficient are obtained.

The current loop design uses a simplified permanent magnet synchronous machine model, as shown in fig. 4. In the figure R_sIs the motor stator resistance, L_sThe inductance of the stator of the motor can be obtained by inquiring a motor manual. The simplified motor model is a typical first-order system, which has poles, inertia and delay effect, in order to accelerate the system response and reduce the delay, the current loop regulator is designed to be a PI regulator, and the structural block diagram of the current loop is shown in FIG. 5, wherein k is_piAnd k_iiProportional coefficient and integral coefficient, K, of current loop PI controller_uFor the gain of the PWM amplifier, usually the DC bus voltage of the motor controller, which can be determined by the designer from the actual voltage, K_fiFor the current feedback factor, usually the reciprocal of the maximum value of the motor phase current, which is known from motor handbooks, i_rinFor current loop input, i_outFor current loop output, i_fbIs current feedback. Since the electromagnetic time constant of the electromagnetic loop is much smaller than the electromechanical time constant, the back electromotive force can be considered to be basically unchanged in the current loop adjusting process, and the open loop transfer function of the current loop can be obtained as

Fig. 5 shows that the current closed-loop regulator, i.e. the PI regulator of the current loop, is combined with the simplified model of the motor by designing an appropriate k_piAnd k_iiThe coefficients can eliminate poles in the motor model to achieve the optimal response of motor current loop control. Due to the existence of the current loop, the current spike can be effectively inhibited, the control precision and stability of the system are improved, and the current loop has a strong inhibiting effect on various disturbances.

Get K_fiInputting the ratio of the maximum value to the maximum current of the motor for the current controller, and performing normalization processing when designing system control parameters to make the input of the current loop controller 1, and K_fiI.e. the reciprocal of the maximum value of the motor current, and a₁＝R_s/L_s，a₂＝K_uK_fi/L_sTo obtain a current loop closed loop transfer function

The free oscillation frequency of the system is omega_nDamping ratio is epsilon, and current loop bandwidth is omega_bThus can obtain

The important function of the current loop is that the smaller the overshoot is, the better the overshoot is, the faster the response is, and therefore the damping ratio can be selected to be 0.707. In the case of parametric design, the current loop bandwidth ω is usually determined as a function of the motor current alternating frequency_b，ω_bShould be greater than the maximum alternating frequency of the motor current. The proportional coefficient k of the current loop PI controller can be obtained according to the formula (14)_piAnd current loop integral coefficient k_iiAnd finishing the construction of the current loop.

In the invention, after the construction of the current loop is completed, the speed loop is constructed according to the current loop, and the speed loop proportion coefficient and the speed loop integral coefficient are obtained.

And (3) correcting a closed loop transfer function according to the current loop of the formula (13), and performing approximate order reduction processing on a high-order link of the closed loop transfer function, so that the current loop can be equivalent to a first-order inertia link. The speed loop system comprises load disturbance, and the speed loop controller can be designed into a PI controller to realize the rotation speed non-static control, so that the system is corrected into a typical II type system, as shown in figure 6. The speed loop regulator has a transfer function of

Wherein, K_p＝K_iv，k_ivIs a velocity loop integral coefficient, T₁＝K_pv/K_iv，k_pvIs the velocity ring scaling factor. K in FIG. 6_fvFor the speed feedback coefficient, the value is the reciprocal of the maximum rotation speed of the motor in the normal normalization process, and can be obtained by inquiring in a motor manual, K_tIs the motor moment coefficient, J is the moment of inertia of the rotating part, T₂The time constant after the equivalent reduction of the current loop can be obtained by the reduction of the second-order transfer function in the formula (13).

The open loop transfer function of the velocity loop system from FIG. 6 is

Wherein, K_tThe torque coefficient of the motor can be obtained by inquiring a motor manual. The open-loop logarithmic frequency characteristic of the velocity loop system obtained from the above is shown in fig. 7. In order to make the system have better stability, T is designed₁＞T₂The turn frequencies are ω₁＝1/T₁、ω₂＝1/T₂The velocity ring cut-off frequency is omega_cThen, the stability margin K of the system can be obtained as

K＝ω₁ω_c (17)

The phase angle margin gamma reflects the relative stability of the system, which can be obtained according to equation (17),

γ＝arctanω_cT₁-arctanω_cT₂ (18)

according to the rule of the maximum phase angle margin commonly used in engineering, the phase angle margin of the speed loop system can be obtained to obtain the extreme value gamma_maxUnder the conditions of

Wherein h is a medium frequency bandwidth, preferably 5.

According to the derivation, the time constant T after equivalent reduction of the current loop is obtained₂And equation (19) can obtain T₁And current loop cutoff frequency ω_cThe stability margin K can be obtained according to equation (17), according to equations (16) and T₁＝K_pv/K_ivThe proportional coefficient k of the speed ring can be obtained_pvAnd velocity loop integral coefficient k_ivTo complete the construction of the speed loop.

In the invention, after the construction of a speed loop is completed, a dimension reduction torque observer is constructed, a load torque and a torque observer coefficient are obtained, and the load torque is multiplied by the torque observer coefficient and then fed back to a current loop input to complete the motor speed regulation control based on the dimension reduction observer.

As shown in fig. 8, the motor speed regulation control flow based on the dimension reduction observer includes an observation module based on the load torque and the load rotation speed of the dimension reduction observer, and a permanent magnet synchronous motor vector control module based on a current loop and a rotation speed loop double closed loop of the observation torque compensation. From the above derivation, according to s²-(α+β)s+αβ＝0、Andthe coefficient k of the torque observer can be obtained₁And k₂. The poles alpha and beta are estimated according to the current loop cut-off frequency and the speed loop cut-off frequency, and should be larger than the speed loop bandwidth and smaller than the current loopWidth, by adjusting α and β appropriately, such that k is calculated₁And k₂The requirement that the observed rotating speed follows the actual rotating speed is met.

The invention provides a permanent magnet motor dimension reduction torque observation method based on a dimension reduction observer, and the method can realize the observation of load torque only by collecting the current and the rotating speed of the motor, thereby reducing the complexity of the system; the invention provides a permanent magnet synchronous motor rotating speed and current double closed-loop control method based on observation torque compensation, which can realize effective inhibition on load torque and achieve strong anti-interference effect; the invention also provides a permanent magnet synchronous motor current loop and speed loop design method and a parameter calculation method based on the motor parameters, the method can preliminarily determine the system control parameter range, and the system debugging efficiency is effectively improved. The technical scheme of the invention can improve the dynamic characteristic, the control precision and the disturbance resistance of the electric fuel pump system, thereby achieving the effect of improving the dynamic control quality and the comprehensive energy efficiency of the engine.

For a further understanding of the present invention, the following detailed description of the embodiments of the present invention is provided with reference to fig. 1 to 9.

Taking a certain electric fuel pump speed regulating system as an example, the control method of the high-precision and strong-disturbance-rejection permanent magnet synchronous motor based on the dimensionality reduction observer is verified, and compared with the dynamic characteristics and the dynamic load disturbance resistance of the traditional PI control method, the full-dimensional observer control method and the extended sliding film control method, the result is as follows.

The speed response curve when the given motor speed command is 2000rpm is shown in fig. 9, and it can be known from fig. 9 that the speed feedback under the two control algorithm conditions can realize the fast speed command tracking performance, and the response time is less than 5 ms. The improved PI controller with the added dimension reduction load torque compensation obtains no overshoot of the rotating speed feedback, while the traditional PI controller obtains the rotating speed feedback overshoot of about 100 rpm. Therefore, compared with the traditional PI controller, the speed regulation control method based on the dimensionality reduction observer has the advantages of good regulation rapidity and obvious rotation speed tracking stability.

In order to research the influence of load compensation on the system interference resistance, and compare and analyze the difference between a load torque observer and a traditional PI control method, the test comparison and analysis are carried out on the motor speed regulation tracking performance under the variable load condition. Setting the motor rotating speed command to be 1000rpm, and when the rotating speed reaches a steady state, enabling the motor load torque value to be suddenly increased from 0 N.m to 10 N.m at the time of 0.2 s; at the time of 0.3s, the motor load torque value is suddenly reduced from 10 N.m to 5 N.m, and the rotating speed fluctuation under the condition of variable load is obtained and is shown in the table 1.

TABLE 1 comparison table of rotation speed fluctuation of each anti-load algorithm

It can be known from table 1 that when the given rotation speed is 1000rpm, compared with the traditional PI control, the system rotation speed fluctuation is obviously reduced after the load compensation is introduced, and the response time is obviously improved. The system rotation speed fluctuation is maximum under the traditional PI control condition, and reaches +140rpm and-70 rpm, and the response time is longest, and is respectively 80ms and 45 ms; the system rotating speed fluctuation value added with the reduced-order load torque observed value feedforward compensation algorithm is +55rpm and-25 rpm, the response time is 30ms and 20ms, the response time is short, and the response is quick. The analysis shows that the reduced-order load torque observer has short response time and good rapidity, and can meet the load sudden change disturbance rejection capability in the application of the electric fuel pump.

In summary, the invention provides a motor speed regulation control method based on a dimension reduction observer, which can realize speed regulation control of a high-precision and strong-disturbance-resistance permanent magnet synchronous motor by constructing an observation module based on load torque and load rotating speed of the dimension reduction observer and a permanent magnet synchronous motor vector control module based on a current loop and rotating speed loop double-closed loop of observation torque compensation, thereby improving dynamic characteristics, control precision and disturbance-resistance capability of an electric fuel pump system, and further achieving the effect of improving dynamic control quality and comprehensive energy efficiency of an engine. Compared with the prior art, the technical scheme of the invention can solve the technical problem that the traditional permanent magnet synchronous motor control method in the prior art cannot meet the speed regulation control requirements of high precision and strong interference resistance.

Spatially relative terms, such as "above … …," "above … …," "above … …," "above," and the like, may be used herein for ease of description to describe one device or feature's spatial relationship to another device or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is turned over, devices described as "above" or "on" other devices or configurations would then be oriented "below" or "under" the other devices or configurations. Thus, the exemplary term "above … …" can include both an orientation of "above … …" and "below … …". The device may be otherwise variously oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

It should be noted that the terms "first", "second", and the like are used to define the components, and are only used for convenience of distinguishing the corresponding components, and the terms have no special meanings unless otherwise stated, and therefore, the scope of the present invention should not be construed as being limited.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.