阅读说明：本技术 一种电机的软件容错控制方法及其控制系统 (Software fault-tolerant control method and system for motor ) 是由 唐其鹏 盛明钢 吴建华 张会永 于 2019-10-11 设计创作，主要内容包括：本发明公开了一种电机的软件容错控制方法及其控制系统。该电机的软件容错控制方法包括：检测位置编码器是否出现故障；若是,计算电机的定子磁链；根据所述定子磁链,计算所述电机的转子磁链；根据所述转子磁链,确定所述转子的位置估计值；通过旋转变换,计算磁链偏差；根据所述磁链偏差,调整所述位置估计值,获得所述转子的位置并输出。(The invention discloses a software fault-tolerant control method and a software fault-tolerant control system for a motor. The software fault-tolerant control method of the motor comprises the following steps: detecting whether the position encoder fails; if yes, calculating a stator flux linkage of the motor; calculating a rotor flux linkage of the motor according to the stator flux linkage; determining a position estimation value of the rotor according to the rotor flux linkage; calculating flux linkage deviation through rotation transformation; and adjusting the position estimation value according to the flux linkage deviation to obtain and output the position of the rotor.)

1. A software fault-tolerant control method of a motor is characterized by comprising the following steps:

Detecting whether the position encoder fails;

If yes, calculating a stator flux linkage of the motor;

Calculating a rotor flux linkage of the motor according to the stator flux linkage;

Determining a position estimation value of the rotor according to the rotor flux linkage;

Calculating flux linkage deviation through rotation transformation;

And adjusting the position estimation value according to the flux linkage deviation to obtain and output the position of the rotor.

2. The method according to claim 1, wherein the calculating the flux linkage deviation by rotational transformation specifically comprises:

carrying out rotation transformation on the integral result of the stator flux linkage according to the position estimation value;

And processing the result after the rotation transformation by using a low-pass filter to obtain the flux linkage deviation.

3. The method of claim 1, further comprising:

The stator flux linkage is processed using a high pass filter.

4. The method of claim 1, wherein the relationship between the stator flux linkage and the rotor flux linkage satisfies the following equation:

Wherein psi_αβsFor stator flux linkage psi_αβrfor rotor flux linkage, theta_ris the included angle between the rotor flux linkage and the alpha axis.

5. the method of claim 1, wherein the stator flux linkage is calculated by the following equation:

ψ_αβs＝∫(V_αβ-R_si_αβ)dt

Wherein, V_αβIs the stator voltage, R_sIs stator resistance, i_αβIs the stator current.

6. The method of claim 5, wherein the stator voltage of the motor is a voltage setpoint of a current loop output.

7. A method according to claim 1, characterized in that the proportion of dead time is reduced by reducing the switching frequency of the power device.

8. a method according to claim 1, characterized in that the proportion of the dead time which acts is reduced by increasing the effective output voltage.

9. Method according to claim 8, characterized in that in the low speed phase of the machine the reactive component is made equal to a preset value to increase the effective output voltage.

10. a control system of a gantry crane driver, which is applied to a gantry crane motor, is characterized by comprising: the device comprises a speed outer closed loop, two current inner closed loops, a first coordinate transformation matrix, a second coordinate transformation matrix, a power module, a position encoder and a rotor position estimator;

The rotor position estimator applies the software fault-tolerant control method according to any one of claims 1-9 to calculate the position of the rotor.

Technical Field

The invention relates to the technical field of motor control of a gantry crane, in particular to a software fault-tolerant control method and a software fault-tolerant control system for a motor.

Background

software fault tolerance control refers to the ability of a computer to tolerate faults using redundant resources. I.e., in the event of a failure, there is still the ability to continue the completion of the specified algorithm. For example, for a motor model, when its position encoder for detecting the rotor position fails, the rotor position needs to be estimated by an additional position estimator to ensure that the control system can still maintain effective control of the gantry crane motor.

However, for the existing software fault-tolerant scheme, the rotor position estimation is inaccurate due to the small back electromotive force when the motor rotates at low speed or zero speed, so that the loading capacity of the system is reduced. Even the door machine can not be normally opened and closed. In addition, due to the use of the filter, the estimation deviation of the rotor position can be generated, the loading capacity of the system is also reduced, and the gantry crane cannot be normally opened or closed when in heavy load.

therefore, it is highly desirable to provide a suitable rotor position estimation scheme to improve and enhance the software fault tolerance of the control system, and ensure that the motor of the gantry crane can be used smoothly.

Disclosure of Invention

The invention aims to provide a software fault-tolerant control method and a software fault-tolerant control system for a motor, which can solve the problem of inaccurate rotor position estimation in the prior art.

In a first aspect, an embodiment of the present invention provides a software fault-tolerant control method for a motor. The software fault-tolerant control method comprises the following steps:

detecting whether the position encoder fails;

If yes, calculating a stator flux linkage of the motor;

Calculating a rotor flux linkage of the motor according to the stator flux linkage;

Determining a position estimation value of the rotor according to the rotor flux linkage;

Calculating flux linkage deviation through rotation transformation;

And adjusting the position estimation value according to the flux linkage deviation to obtain and output the position of the rotor.

Further, the calculating the flux linkage deviation through rotation transformation specifically includes:

carrying out rotation transformation on the integral result of the stator flux linkage according to the position estimation value;

And processing the result after the rotation transformation by using a low-pass filter to obtain the flux linkage deviation.

Further, the method further comprises: the stator flux linkage is processed using a high pass filter.

Further, the relationship between the stator flux linkage and the rotor flux linkage satisfies the following equation:

Wherein psi_αβsfor stator flux linkage psi_αβrFor rotor flux linkage, theta_rIs the included angle between the rotor flux linkage and the alpha axis.

Further, the stator flux linkage is calculated by the following equation:

ψ_αβs＝∫(V_αβ-R_si_αβ)dt

Wherein, V_αβIs the stator voltage, R_sIs stator resistance, i_αβis the stator current.

further, the stator voltage of the motor is a given voltage value output by the current loop.

Further, the action proportion of the dead time of the inverter is reduced by reducing the switching frequency of the power device.

Further, the proportion of the dead time of the inverter is reduced by increasing the effective output voltage.

Further, in the low-speed stage of the motor, the reactive component is made equal to a preset value to increase the effective output voltage.

in a second aspect, an embodiment of the present invention provides a control system for a door operator driver, which applies a door operator motor. It includes: the device comprises a speed outer closed loop, two current inner closed loops, a first coordinate transformation matrix, a second coordinate transformation matrix, a power module, a position encoder and a rotor position estimator; the rotor position estimator applies the software fault-tolerant control method to calculate and obtain the position of the rotor.

The software fault-tolerant control method provided by the embodiment of the invention can obtain a more accurate rotor position through a proper estimator under the condition that an encoder has errors, so that the estimation precision of the rotor position is improved, and a motor of a gantry crane can have normal door opening and closing capabilities under the heavy load condition.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a functional block diagram of a control system according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of a rotor position estimator according to an embodiment of the present invention.

Fig. 3 is a schematic diagram of a software fault tolerance control method according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. 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 to be understood that the terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in the specification of the present invention and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

It should be further understood that the term "and/or" as used in this specification and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

Referring to fig. 1, fig. 1 is a control system of a door operator driver according to an embodiment of the present invention, which employs a door operator motor.

The control system includes: a speed outer closed loop 11, two current inner closed loops (12a, 12b), a first coordinate transformation matrix 13, a second coordinate transformation matrix 14, a power module 15, a position encoder 16, and a rotor position estimator 17.

Wherein, through the control of the power module 15, the door motor can be driven correspondingly to execute the normal door opening and closing operation. In normal operation, the position encoder 16 (or other suitable sensor) provides a captured rotor position.

In the event of a failure of the position encoder 16, the corresponding rotor position information will not be provided. At this time, the rotor position at this time is estimated and determined by the rotor position estimator 17 in a set position estimation step based on parameters such as the voltage of the motor.

In the context of figure 1 of the drawings,For a given angular frequency, ω, of the rotor_rTo calculate the angular frequency of the rotor obtained. Providing the adjusted angular frequency to a speed outer ring for calculation to obtain a given active component

collecting current i of motor of gantry crane_αβrespectively outputting corresponding active components i through a second coordinate transformation matrix 14_qAnd a reactive component i_dThe calculated value of (a). Given active and reactive components are adjusted using the two calculated values and then input into two current inner closed loops (12a, 12 b).

The outputs of the two current inner closed loops are provided to a first coordinate transformation matrix, and a given stator voltage can be output after calculationIs provided to the power module 15, and is controlled by turning on and off the switching tube in the power module 15 correspondinglyThe motor of the gantry crane is controlled to execute corresponding operation.

Of course, the rotor position information obtained by the final calculation is also fed back to the first coordinate conversion matrix and the second coordinate conversion matrix for feedback calculation control, and after differentiation, the angular frequency of the rotor is obtained for negative feedback adjustment.

In some embodiments, the power module 15 typically inserts a short dead time to prevent the upper and lower tubes from passing through. Such dead time may have a certain effect on the stator voltage (especially in a low-speed operation region of the motor), thereby causing an error in the rotor position outputted by the rotor position estimator and reducing the accuracy.

Therefore, in the low-speed stage of the motor, the reactive component is equal to the preset value so as to increase the effective output voltage or the effective output voltage is increased, the dead time is reduced, and the rotor position estimation precision is improved.

Fig. 2 is a schematic structural diagram of a rotor position estimator according to an embodiment of the present invention. As shown in fig. 2, the rotor position estimator may perform the position estimation of the rotor in the following manner, and output a corresponding rotor position value:

Firstly, the stator voltage, the stator resistance and the corresponding stator current (R) are obtained_si_αβAnd V_αβ). Then, the difference is integrated to obtain the stator flux linkage psi_αβs。

in order to eliminate the effect of the dc offset in the difference on the integration, the stator flux linkage is processed using a high pass filter HPF. After processing, solving and obtaining the rotor flux linkage psi according to the relation between the stator flux linkage and the rotor flux linkage_αβr. Finally, solving and obtaining the phase angle of the rotor flux linkage through the Arg function to determine the estimated value theta of the rotor position_rEst。

In some embodiments, to further eliminate the effect of the high pass filter on the amplitude and phase of the input ac signal, the estimated value of the rotor position obtained by the solution may also be adjusted and optimized accordingly.

Specifically, the estimated value θ of the rotor position is used_rEstFor the integrated stator flux linkage psi_αβsPerforming rotation transformation (T) to obtain flux linkage deviation delta psi_αβ。

Estimation value theta of rotor position when gantry crane system is stably operated_rEstAnd stator flux linkage psi_αβscan be considered to be approximately the same. Thus, the flux linkage deviation after the rotation conversion is a direct current amount. And the dc bias caused by the pure integrator is converted to an ac flow.

The low pass filter LPF does not affect the dc current. Therefore, the dc offset can be separated by the processing of the low pass filter LPF, so that an accurate rotor position deviation value Δ θ can be obtained.

Finally, based on the rotor position deviation value Δ θ, the position estimation value can be adjusted and optimized, thereby obtaining a more accurate rotor position estimation result.

In summary, during the actual operation of the actual door operator control system, the software fault-tolerant control method includes the following steps:

S100, judging whether the position encoder has a fault. If yes, go to step S110, otherwise, go to the normal control flow.

And S110, calculating the stator flux linkage of the motor.

Specifically, the stator flux linkage equation of the permanent magnet synchronous gantry crane in the two-phase stationary coordinate system is expressed by the following equation (1):

ψ_αβs＝∫(V_αβ-R_si_αβ)dt (1)

wherein psi_αβsfor stator flux linkage psi_fFor rotor flux linkage, theta_ris the included angle between the rotor flux linkage and the alpha axis.

In some embodiments, for convenience of implementation, the voltage set-point output by the current loop shown in fig. 1 can be directly used as the stator voltage of the motor.

And S120, calculating a corresponding rotor flux linkage according to the stator flux linkage of the motor.

before step S120, the stator flux linkage may also be processed using a high-pass filter, and the corresponding rotor flux linkage may be calculated using the processed stator flux linkage.

In the present embodiment, the relationship between the stator flux linkage and the rotor flux linkage satisfies the following equation (2):

Wherein psi_αβsFor stator flux linkage psi_αβrFor rotor flux linkage, L_sIs a stator inductance,/_sαβIs stator current, θ_rIs the angle between the rotor flux linkage and the alpha axis.

And S130, determining a position estimation value of the rotor according to the rotor flux linkage.

Specifically, the position estimation value of the rotor may be calculated by the following equation (3):

θ_rEst＝Arg(ψ_αβr) (3)

Wherein, theta_rEstIs an estimate of the position of the rotor.

And S140, calculating flux linkage deviation through rotation transformation.

Specifically, the calculation method of the flux linkage deviation includes: firstly, the integral result of the stator flux linkage is subjected to rotation transformation by using the position estimated value of the rotor. Then, the result after the rotation conversion is processed using a low-pass filter, and the flux linkage deviation is obtained.

Flux linkage deviation delta psi_αβ＝ψ_fe^jΔθ. Wherein Δ θ ═ θ_r-θ_rEst。

and S150, adjusting the position estimation value according to the flux linkage deviation, and obtaining and outputting the position of the rotor.

in summary, in the software fault-tolerant control method provided by the embodiment of the invention, at the low rotation speed stage of the motor, the switching frequency of the power device is properly reduced to reduce the influence of the dead zone effect on the output voltage, and the d-axis reactive current component is properly controlled to increase the output voltage and improve the start load capacity of the system.

Further, a rotation transformation matrix is constructed by using the rotor position estimation value of the motor model method to compensate the position estimation deviation caused by the filter. Through the three methods, the rotor position estimation precision is effectively improved, and the door machine system also has normal door opening and closing capabilities when an encoder fails.

the embodiments are described in a progressive manner in the specification, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

it is further noted that, in the present specification, relational terms such as first and second, and the like are 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. The use of the phrase "including a" does not exclude the presence of other, identical elements in a process, method, article, or apparatus that comprises the same element, unless the context clearly dictates otherwise.