A current-voltage adaptive control method and control device for a permanent magnet synchronous motor

Abstract

The application discloses a current-voltage adaptive control method and a control device of a permanent magnet synchronous motor, and the method comprises the following steps: obtaining a current limit frequency protection value, a phase current amplitude, a voltage limit amplitude threshold value and a modulation voltage amplitude of the permanent magnet synchronous motor, and calculating a current limit amplitude attenuation rate and a voltage limit amplitude attenuation rate; superimposing the current limit amplitude attenuation rate to an output of a first proportional integral controller in a speed control module to obtain a quadrature axis current instruction and a direct axis current instruction; superimposing the voltage limit amplitude attenuation rate to an output of a second proportional integral controller in a current control module to obtain a quadrature axis voltage instruction and a direct axis voltage instruction; performing Park inverse transformation and modulation on the quadrature axis voltage instruction and the direct axis voltage instruction to obtain three-phase voltage output for driving the motor, and controlling the permanent magnet synchronous motor according to the three-phase voltage. The application can perform adaptive control on output voltage or output current of the motor drive based on the voltage limit amplitude attenuation rate or the current limit amplitude attenuation rate, so as to ensure safe and reliable operation of the permanent magnet synchronous motor.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of permanent magnet synchronous motor, and particularly relates to a current-voltage adaptive control method and control device of permanent magnet synchronous motor. BACKGROUND

[0002] In the variable frequency algorithm platformization project test, the adaptability of motor driving under load mutation and voltage mutation needs to be evaluated. In the case of sudden load increase, in order to provide greater torque for the motor, the variable frequency drive control will increase the output current. However, excessive current can cause damage to the power devices of the frequency converter, or demagnetization of the motor, etc., thus requiring shutdown protection. In the case of voltage sag, for variable frequency converters with power factor correction circuit, the bus voltage can be stabilized and controlled by PFC to slow down the voltage change. However, for passive variable frequency converters, the energy storage of electrolytic capacitor is used to maintain the voltage, which has little effect on slowing down under heavy load. Voltage mutation will affect the output of motor driving, and thus cause voltage saturation and over-regulation, etc. If no response is made, it will cause loss of step, overcurrent, and thus abnormal shutdown.

[0003] In the case of load mutation, if the motor still needs to be maintained, the motor speed needs to be reduced. Due to the slow response of the speed loop in the existing control method, simply reducing the speed command cannot limit the frequency in time when the load mutates, thus causing overcurrent shutdown. To respond to voltage mutation, the conventional variable frequency algorithm reduces the output voltage through field weakening control to achieve normal operation of the motor. However, field weakening control generally responds slowly, and in the case of rapid voltage change, it will cause current fluctuation and increase the probability of overcurrent shutdown. Moreover, due to the slow response of the speed loop, in the case of rapid voltage drop, the speed reduction is not timely, which can cause loss of step or overcurrent shutdown. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a current-voltage adaptive control method and control device of permanent magnet synchronous motor, which can adaptively control the output voltage or output current of motor driving based on the voltage amplitude attenuation rate or the current amplitude attenuation rate, to ensure the safe and reliable operation of the permanent magnet synchronous motor.

[0005] The first embodiment of the present application provides a current-voltage adaptive control method of permanent magnet synchronous motor, comprising:

[0006] obtaining a current frequency limiting protection value, a phase current amplitude, a voltage amplitude threshold value and a modulation voltage amplitude of the permanent magnet synchronous motor;

[0007] According to the current frequency limiting protection value and the phase current amplitude, a current amplitude attenuation rate is calculated; according to the voltage amplitude threshold value and the modulation voltage amplitude, a voltage amplitude attenuation rate is calculated;

[0008] The current amplitude attenuation rate is superimposed to the output of the first proportional integral controller in the speed control module to obtain a quadrature axis current instruction Iq* and a direct axis current instruction Id*; the voltage amplitude attenuation rate is superimposed to the output of the second proportional integral controller in the current control module to obtain a quadrature axis voltage instruction Vq* and a direct axis voltage instruction Vd*;

[0009] The quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* are subjected to Park inverse transformation and modulation to obtain three-phase voltage output for driving the motor, and the permanent magnet synchronous motor is controlled according to the three-phase voltage.

[0010] The second embodiment of the present application provides a current and voltage adaptive control method of a permanent magnet synchronous motor, and the method further comprises:

[0011] If the current amplitude attenuation rate is less than the voltage amplitude attenuation rate, the current amplitude attenuation rate is superimposed to the speed control module;

[0012] If the current amplitude attenuation rate is greater than the voltage amplitude attenuation rate, the voltage amplitude attenuation rate is superimposed to the speed control module.

[0013] The third embodiment of the present application provides a current and voltage adaptive control method of a permanent magnet synchronous motor, and the method further comprises:

[0014] The speed control module is subjected to amplitude limiting processing through a first amplitude limiting link to ensure the stability of a position observer; the current amplitude attenuation rate is subjected to amplitude limiting processing through a second amplitude limiting link to realize the rapid following of output current when a load suddenly changes; and the voltage amplitude attenuation rate is subjected to amplitude limiting processing through a third amplitude limiting link to realize the rapid following of output voltage when a voltage suddenly changes.

[0015] In the fourth embodiment of the present application, when the current amplitude attenuation rate is less than 1 or the voltage amplitude attenuation rate is less than 1, the speed instruction in the speed control module is less than or equal to an observed speed.

[0016] In the fifth embodiment of the present application, the calculation formula of the current amplitude attenuation rate is: Ratio cur =Ilim / Im*;

[0017] Wherein, Ratio cur is the current amplitude attenuation rate, Ilim is a current amplitude limiting protection value, and Im* is a phase current amplitude. Id* is a direct axis current instruction, and Iq* is a quadrature axis current instruction.

[0018] The calculation formula of the voltage amplitude attenuation rate is: Ratio sat =Vsat / Vm*;

[0019] Wherein, Ratio sat is the voltage amplitude attenuation rate, Vsat is the voltage amplitude threshold value, Vm* is the modulation voltage amplitude, and the modulation voltage amplitude Vd* is the direct-axis voltage instruction, and Vq* is the quadrature-axis voltage instruction.

[0020] The sixth embodiment of the application provides a current and voltage adaptive control device of a permanent magnet synchronous motor, which comprises:

[0021] An acquisition module is configured to acquire a current frequency limiting protection value, a phase current amplitude, a voltage amplitude threshold value and a modulation voltage amplitude of the permanent magnet synchronous motor.

[0022] A calculation module is configured to calculate a current amplitude attenuation rate according to the current frequency limiting protection value and the phase current amplitude, and calculate a voltage amplitude attenuation rate according to the voltage amplitude threshold value and the modulation voltage amplitude.

[0023] An adaptive module is configured to superimpose the current amplitude attenuation rate to an output of a first proportional integral controller in a speed control module to obtain a quadrature-axis current instruction Iq* and a direct-axis current instruction Id*, and superimpose the voltage amplitude attenuation rate to an output of a second proportional integral controller in a current control module to obtain a quadrature-axis voltage instruction Vq* and a direct-axis voltage instruction Vd*.

[0024] A control module is configured to perform Park inverse transformation and modulation on the quadrature-axis voltage instruction Vq* and the direct-axis voltage instruction Vd* to obtain a three-phase voltage output for driving the motor, and control the permanent magnet synchronous motor according to the three-phase voltage.

[0025] In the seventh embodiment of the application, the current and voltage adaptive control device of the permanent magnet synchronous motor further comprises a forward feedback module configured to:

[0026] If the current amplitude attenuation rate is less than the voltage amplitude attenuation rate, the current amplitude attenuation rate is superimposed into the speed control module.

[0027] If the current amplitude attenuation rate is greater than the voltage amplitude attenuation rate, the voltage amplitude attenuation rate is superimposed into the speed control module.

[0028] In the eighth embodiment of the application, the current and voltage adaptive control device of the permanent magnet synchronous motor further comprises an amplitude limiting module configured to:

[0029] The speed control module is limited by a first limiting link to ensure stability of a position observer; the current limiting attenuation rate is limited by a second limiting link to realize rapid following of output current when a load suddenly changes; and the voltage limiting attenuation rate is limited by a third limiting link to realize rapid following of output voltage when a voltage suddenly changes.

[0030] The ninth embodiment of the application provides a current and voltage adaptive control device for a permanent magnet synchronous motor, wherein when the current limiting attenuation rate is less than 1 or the voltage limiting attenuation rate is less than 1, the speed instruction in the speed control module is less than or equal to the observed speed.

[0031] The tenth embodiment of the application provides a current and voltage adaptive control device for a permanent magnet synchronous motor, wherein the calculation formula of the current limiting attenuation rate is: Ratio cur = Ilim / Im*;

[0032] Wherein, Ratio cur is the current limiting attenuation rate, Ilim is the current limiting protection value, and Im* is the phase current amplitude. Id* is the direct-axis current instruction, and Iq* is the quadrature-axis current instruction.

[0033] The calculation formula of the voltage limiting attenuation rate is: Ratio sat = Vsat / Vm*;

[0034] Wherein, Ratio sat is the voltage limiting attenuation rate, Vsat is the voltage limiting threshold value, and Vm* is the modulation voltage amplitude. Vd* is the direct-axis voltage instruction, and Vq* is the quadrature-axis voltage instruction.

[0035] The current-voltage adaptive control method and control device of the permanent magnet synchronous motor provided by the embodiment of the present application have the beneficial effects that, compared with the prior art, the current-voltage adaptive control method and control device of the permanent magnet synchronous motor provided by the embodiment of the present application have the beneficial effects that: the current limiting frequency protection value, the phase current amplitude, the voltage limiting threshold value and the modulation voltage amplitude of the permanent magnet synchronous motor are obtained; the current limiting amplitude attenuation rate is calculated according to the current limiting frequency protection value and the phase current amplitude; the voltage limiting amplitude attenuation rate is calculated according to the voltage limiting threshold value and the modulation voltage amplitude; the current limiting amplitude attenuation rate is superimposed to the output of the first proportional integral controller in the speed control module to obtain the quadrature axis current instruction Iq* and the direct axis current instruction Id*; the voltage limiting amplitude attenuation rate is superimposed to the output of the second proportional integral controller in the current control module to obtain the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd*; the Park inverse transformation and modulation are performed on the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* to obtain the three-phase voltage output for driving the motor, and the permanent magnet synchronous motor is controlled according to the three-phase voltage. The embodiment of the present application can adaptively control the output voltage of the motor drive based on the voltage limiting amplitude attenuation rate and adaptively control the output current of the motor drive based on the current limiting amplitude attenuation rate, so as to ensure the safe and reliable operation of the permanent magnet synchronous motor. BRIEF DESCRIPTION OF DRAWINGS

[0036] Figure 1 is a flowchart of a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0037] Figure 2 is a schematic diagram of a speed control module in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0038] Figure 3 is a schematic diagram of a current control module in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0039] Figure 4 is a schematic diagram of a modulation sampling control module in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0040] Figure 5 is a schematic diagram of a position estimation module in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0041] Figure 6 is a schematic diagram of a drive control model in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0042] Figure 7is a schematic diagram of a control model in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0043] Figure 8 is a flowchart of forward feedback in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0044] Figure 9 is a flowchart of limiting processing in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application;

[0045] Figure 10 is a structural schematic diagram of a current-voltage adaptive control device of a permanent magnet synchronous motor provided by an embodiment of the present application. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0047] Please refer to Figure 1 , Figure 1 is a flowchart of a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application. The current-voltage adaptive control method of the permanent magnet synchronous motor comprises the following steps.

[0048] S1, obtaining a current frequency-limiting protection value, a phase current amplitude, a voltage limiting threshold value and a modulation voltage amplitude of the permanent magnet synchronous motor;

[0049] S2, calculating a current limiting attenuation rate according to the current frequency-limiting protection value and the phase current amplitude, and calculating a voltage limiting attenuation rate according to the voltage limiting threshold value and the modulation voltage amplitude;

[0050] S3, superimposing the current limiting attenuation rate to an output of a first proportional integral controller in a speed control module to obtain a quadrature axis current instruction Iq* and a direct axis current instruction Id*, and superimposing the voltage limiting attenuation rate to an output of a second proportional integral controller in a current control module to obtain a quadrature axis voltage instruction Vq* and a direct axis voltage instruction Vd*;

[0051] S4, performing Park inverse transformation and modulation on the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* to obtain a three-phase voltage output for driving the motor, and controlling the permanent magnet synchronous motor according to the three-phase voltage.

[0052] Specifically, the embodiment provides a current-voltage adaptive control method of a permanent magnet synchronous motor, obtains a current frequency-limiting protection value Ilim, a phase current amplitude Im*, a voltage amplitude-limiting threshold value Vsat and a modulation voltage amplitude Vm* of the permanent magnet synchronous motor. According to the current frequency-limiting protection value Ilim and the phase current amplitude Im*, a current amplitude-limiting decay rate Ratio cur is calculated; according to the voltage amplitude-limiting threshold value Vsat and the modulation voltage amplitude Vm*, a voltage amplitude-limiting decay rate Ratio sat is calculated. The current amplitude-limiting decay rate Ratio cur is superimposed on the output of a first proportional integral controller in a speed control module to obtain a quadrature-axis current instruction Iq* and a direct-axis current instruction Id*; the voltage amplitude-limiting decay rate Ratio sat is superimposed on the output of a second proportional integral controller in a current control module to obtain a quadrature-axis voltage instruction Vq* and a direct-axis voltage instruction Vd*. The quadrature-axis voltage instruction Vq* and the direct-axis voltage instruction Vd* are subjected to Park inverse transformation and modulation to obtain three-phase voltage outputs for driving the motor, and the permanent magnet synchronous motor is controlled according to the three-phase voltage.

[0053] It should be noted that the position sensorless driving of the permanent magnet synchronous motor in the embodiment is realized by using a current vector double-loop control and a position estimation algorithm. Specifically, the driving control model comprises a speed control module, a current control module, a modulation sampling control module and a position estimation module.

[0054] Please refer to Figure 2 , Figure 2 is a schematic diagram of a speed control module in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the application. The speed control module takes a ω* speed instruction as a control target and a ω^ observed speed as a negative feedback input, and calculates an output through a first proportional integral PI controller (or other controllers) to obtain a quadrature-axis current instruction Iq*; at the same time, a direct-axis current instruction Id* is calculated or calibrated based on the quadrature-axis current instruction Iq* and motor-related parameters.

[0055] It should be noted that in permanent magnet synchronous motor control, when the DC bus voltage is rated and the motor output torque is rated, the corresponding motor speed is called base speed. Below the base speed is called the constant torque zone, usually using the unit current maximum torque (mtpa) control to reduce motor copper loss and improve operating efficiency. Above the base speed is called the constant power zone, usually using the field weakening (fw) control to weaken the air gap flux and limit the back electromotive force so that it does not increase with the increase of speed. Mtpa refers to the control method that under the premise of given reference torque, by reasonably allocating the current components of d-axis and q-axis, the stator current is minimized, that is, the maximum torque of the motor under unit current. Mtpa control can reduce motor copper loss, improve operating efficiency and optimize system performance. In addition, since the required output current of the inverter is smaller, the capacity requirement of the inverter can be relatively reduced. Fw control is an important means to realize high-speed operation of permanent magnet synchronous motor, which weakens the air gap flux and limits the back electromotive force so that it does not increase with the increase of speed. When the permanent magnet synchronous motor works in the constant torque zone, in order to improve the efficiency of the driving system, mtpa control strategy is generally adopted; while the permanent magnet synchronous motor works in the constant power zone, in order to ensure the normal work of the motor, fw control strategy must be adopted. In the constant power zone, in order to improve the efficiency of the inverter, the inverter outputs the maximum space voltage vector, at this time, the output torque can be ensured to be consistent with the target torque by controlling the angle between the maximum voltage vector and the q-axis voltage, which is called fw control based on the angle of space voltage vector.

[0056] Referring to Figure 3 , Figure 3 is a schematic diagram of a current control module in a current-voltage adaptive control method of a permanent magnet synchronous motor according to an embodiment of the present application. The current control module takes the q-axis current command Iq* and the d-axis current command Id* as the control target, and the actual q-axis current Iq and the actual d-axis current Id of the motor as the negative feedback input, and calculates the output through the second proportional integral PI controller (or other controller), and then obtains the q-axis voltage command Vq* and the d-axis voltage command Vd* through decoupling (which can also be omitted).

[0057] Referring to Figure 4 , Figure 4is a schematic diagram of a modulation sampling control module in a current voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the application. The modulation sampling control module, wherein the modulation part, the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* are taken as control targets, and the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* in the rotating coordinate system (with the observation phase θ^ as reference) are converted into voltage instructions Vα and Vβ in the stationary coordinate system through Park inverse conversion, and then the three-phase voltage output of the motor is obtained through sine wave modulation (SPWM) or space vector modulation (SVM) to realize effective driving of the motor. The sampling part obtains three-phase currents iu, iv, and iw through sampling of the motor currents (three-phase sampling or single-phase / two-phase sampling reconstruction). The three-phase currents in the three-phase coordinate system are converted into currents iα and iβ in the two-phase stationary coordinate system through Clarke conversion, and then the iα and iβ are converted into the quadrature axis current Iq and the direct axis current Id in the rotating coordinate system (with the observation phase θ^ as reference) through Park conversion.

[0058] Please refer to Figure 5 , Figure 5 is a schematic diagram of a position presumption module in a current voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the application. The position presumption module takes the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd*, and the quadrature axis current Iq and the direct axis current Id, or the voltage instructions Vα and Vβ in the stationary coordinate system and the currents iα and iβ as inputs, and combines the motor related parameters to perform model calculation Position Presumption to obtain the phase difference Δθ between the rotor observation position and the actual position d , and then the phase θ^ of the motor rotor is obtained by integrating the observation speed ω^.

[0059] Based on the above four control modules, a permanent magnet synchronous motor position sensorless driving control model is composed. Please refer to Figure 6 , Figure 6 is a schematic diagram of a driving control model in a current voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the application.

[0060] On the basis of the above permanent magnet synchronous motor position sensorless driving control model, the voltage limiting amplitude decay rate and the current limiting amplitude decay rate are introduced in the embodiment. Please refer to Figure 7 , Figure 7is a schematic diagram of a control model in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application. In the diagram, Vdc is the bus voltage, and Ksat is a setting coefficient (generally not lower than the field weakening threshold). In voltage protection, when the output voltage amplitude Vm is greater than the bus voltage / 2*setting coefficient, voltage protection is triggered. In this embodiment, the current amplitude limiting decay rate is calculated according to the current limiting frequency protection value and the phase current amplitude, and the voltage amplitude limiting decay rate is calculated according to the voltage amplitude limiting threshold and the modulation voltage amplitude. The output voltage of the motor drive is adaptively controlled based on the voltage amplitude limiting decay rate, so as to achieve rapid following of the output voltage when the voltage suddenly changes; the output current of the motor drive is adaptively controlled based on the current amplitude limiting decay rate, so as to achieve rapid following of the output current when the load suddenly changes.

[0061] In another preferred embodiment, the method further comprises:

[0062] If the current amplitude limiting decay rate is less than the voltage amplitude limiting decay rate, the current amplitude limiting decay rate is superimposed into the speed control module;

[0063] If the current amplitude limiting decay rate is greater than the voltage amplitude limiting decay rate, the voltage amplitude limiting decay rate is superimposed into the speed control module.

[0064] Specifically, please refer to Figure 8 , Figure 8 is a flowchart of forward feedback in a current-voltage adaptive control method of a permanent magnet synchronous motor provided by an embodiment of the present application. In this embodiment, if the current amplitude limiting decay rate is less than the voltage amplitude limiting decay rate, the current amplitude limiting decay rate is superimposed into the speed control module; if the current amplitude limiting decay rate is greater than the voltage amplitude limiting decay rate, the voltage amplitude limiting decay rate is superimposed into the speed control module, so as to ensure that the output voltage and the output current do not exceed the limiting value, and voltage and current protection is performed at the same time.

[0065] In yet another preferred embodiment, the method further comprises:

[0066] The speed control module is limited by a first limiting element to ensure the stability of the position observer; the current amplitude limiting decay rate is limited by a second limiting element to achieve rapid following of the output current when the load suddenly changes; and the voltage amplitude limiting decay rate is limited by a third limiting element to achieve rapid following of the output voltage when the voltage suddenly changes.

[0067] Specifically, please refer to Figure 9 , Figure 9is a flowchart of a limiting process in a current-voltage adaptive control method of a permanent magnet synchronous motor according to an embodiment of the present application. The embodiment limits the speed control module through a first limiting link to ensure the stability of the position observer. The current limiting decay rate is limited through a second limiting link to realize the rapid following of the output current when the load suddenly changes. The voltage limiting decay rate is limited through a third limiting link to realize the rapid following of the output voltage when the voltage suddenly changes.

[0068] In another preferred embodiment, when the current limiting decay rate is less than 1 or the voltage limiting decay rate is less than 1, the speed instruction in the speed control module is less than or equal to the observed speed.

[0069] Specifically, in the embodiment, when the current limiting decay rate is less than 1 or the voltage limiting decay rate is less than 1, i.e., Ratio cur <1 or Ratio sat <1, the speed instruction ω* in the speed control module cannot be higher than the observed speed ω^.

[0070] The embodiment limits the speed loop while performing adaptive limiting control on the current or voltage of the permanent magnet synchronous motor drive, ensuring the stability of the position observer in the current or voltage limiting state.

[0071] In another preferred embodiment, the calculation formula of the current limiting decay rate is: Ratio cur = Ilim / Im*.

[0072] Wherein, Ratio cur is the current limiting decay rate, Ilim is the current limiting protection value, and Im* is the phase current amplitude. Id* is the direct-axis current instruction, and Iq* is the quadrature-axis current instruction.

[0073] The calculation formula of the voltage limiting decay rate is: Ratio sat =Vsat / Vm*.

[0074] Wherein, Ratio sat is the voltage limiting decay rate, Vsat is the voltage limiting threshold value, and Vm* is the modulation voltage amplitude. Vd* is the direct-axis voltage instruction, and Vq* is the quadrature-axis voltage instruction.

[0075] It should be noted that in the embodiment, the current limiting decay rate Ratio cur is at most 1, and the voltage limiting decay rate Ratio satThe maximum is 1. When the current limit attenuation rate is less than 1 or the voltage limit attenuation rate is less than 1, that is, Ratio cur <1 or Ratio sat <1, the speed instruction ω* in the speed control module cannot be higher than the observed speed ω^. Since the input side is the speed instruction-observed speed, when the input is less than or equal to 0, the output value will not increase, so when the voltage protection or the current protection occurs, the speed loop output cannot increase. If the speed loop output increases, the current loop input will increase, thereby indirectly causing the output voltage or the output current to increase.

[0076] Correspondingly, the application also provides a current-voltage adaptive control device of a permanent magnet synchronous motor, which can realize all processes of the current-voltage adaptive control method of the permanent magnet synchronous motor in the above embodiment.

[0077] Please refer to Figure 10 , Figure 10 is a structural schematic diagram of a current-voltage adaptive control device of a permanent magnet synchronous motor provided by an embodiment of the application. The current-voltage adaptive control device of the permanent magnet synchronous motor comprises:

[0078] An acquisition module 101 is configured to acquire a current limit frequency protection value of the permanent magnet synchronous motor, a phase current amplitude, a voltage limit threshold value, and a modulation voltage amplitude.

[0079] A calculation module 102 is configured to calculate a current limit attenuation rate according to the current limit frequency protection value and the phase current amplitude, and calculate a voltage limit attenuation rate according to the voltage limit threshold value and the modulation voltage amplitude.

[0080] An adaptive module 103 is configured to superimpose the current limit attenuation rate to an output of a first proportional-integral controller in a speed control module to obtain a quadrature-axis current instruction Iq* and a direct-axis current instruction Id*, and superimpose the voltage limit attenuation rate to an output of a second proportional-integral controller in a current control module to obtain a quadrature-axis voltage instruction Vq* and a direct-axis voltage instruction Vd*.

[0081] A control module 104 is configured to perform Park inverse transformation and modulation on the quadrature-axis voltage instruction Vq* and the direct-axis voltage instruction Vd* to obtain a three-phase voltage output for driving the motor, and control the permanent magnet synchronous motor according to the three-phase voltage.

[0082] Preferably, the device further comprises a forward feedback module 105 configured to:

[0083] If the current limit attenuation rate is less than the voltage limit attenuation rate, the current limit attenuation rate is superimposed to the speed control module.

[0084] If the current limit attenuation rate is greater than the voltage limit attenuation rate, the voltage limit attenuation rate is superimposed into the speed control module.

[0085] Preferably, the device further comprises a limiting module 106 for:

[0086] The speed control module is limited by a first limiting link to ensure the stability of the position observer, the current limit attenuation rate is limited by a second limiting link to realize the rapid following of the output current when the load suddenly changes, and the voltage limit attenuation rate is limited by a third limiting link to realize the rapid following of the output voltage when the voltage suddenly changes.

[0087] Preferably, when the current limit attenuation rate is less than 1 or the voltage limit attenuation rate is less than 1, the speed instruction in the speed control module is less than or equal to the observed speed.

[0088] Preferably, the calculation formula of the current limit attenuation rate is: Ratio cur = Ilim / Im*;

[0089] Wherein, Ratio cur is the current limit attenuation rate, Ilim is the current limit protection value, Im* is the phase current amplitude, and the phase current amplitude Id* is the direct-axis current instruction, and Iq* is the quadrature-axis current instruction.

[0090] The calculation formula of the voltage limit attenuation rate is: Ratio sat = Vsat / Vm*;

[0091] Wherein, Ratio sat is the voltage limit attenuation rate, Vsat is the voltage limit threshold value, Vm* is the modulation voltage amplitude, and the modulation voltage amplitude Vd* is the direct-axis voltage instruction, and Vq* is the quadrature-axis voltage instruction.

[0092] In specific implementation, the working principle, control process and technical effects of the current and voltage adaptive control device of the permanent magnet synchronous motor provided by the embodiment of the application correspond to the current and voltage adaptive control method of the permanent magnet synchronous motor in the above embodiment, and will not be repeated here.

[0093] The embodiment of the application provides a current-voltage adaptive control method and control device of a permanent magnet synchronous motor, the current limiting frequency protection value, the phase current amplitude, the voltage limiting threshold value and the modulation voltage amplitude of the permanent magnet synchronous motor are acquired; the current limiting amplitude attenuation rate is calculated according to the current limiting frequency protection value and the phase current amplitude; the voltage limiting amplitude attenuation rate is calculated according to the voltage limiting threshold value and the modulation voltage amplitude; the current limiting amplitude attenuation rate is superimposed to the output of a first proportional integral controller in a speed control module to obtain a quadrature axis current instruction Iq* and a direct axis current instruction Id*; the voltage limiting amplitude attenuation rate is superimposed to the output of a second proportional integral controller in a current control module to obtain a quadrature axis voltage instruction Vq* and a direct axis voltage instruction Vd*; the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* are subjected to Park inverse transformation and modulation to obtain three-phase voltage output of the motor, and the permanent magnet synchronous motor is controlled according to the three-phase voltage. The embodiment of the application can adaptively control the output voltage of the motor drive based on the voltage limiting amplitude attenuation rate, and adaptively control the output current of the motor drive based on the current limiting amplitude attenuation rate, so that the safe and reliable operation of the permanent magnet synchronous motor is ensured.

[0094] It should be noted that the system embodiments described above are only schematic, wherein the units described as separate components can or can not be physically separate, and the components displayed as units can or can not be physical units, that is, they can be located in one place, or can be distributed on a plurality of network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the embodiment. In addition, the connection relationship between the modules in the system embodiment provided by the application indicates that there is a communication connection between them, which can be realized as one or more communication buses or signal lines. Those skilled in the art can understand and implement it without creative labor.

[0095] The above is the preferred embodiment of the application, and it should be noted that those skilled in the art can make some improvements and refinements without departing from the principles of the application, and these improvements and refinements are also considered within the protection scope of the application.

Claims

1. A current-voltage adaptive control method of a permanent magnet synchronous motor, characterized by, The method comprises the following steps: obtaining a current limiting frequency protection value, a phase current amplitude, a voltage limiting threshold value and a modulation voltage amplitude of a permanent magnet synchronous motor; calculating a current limiting amplitude attenuation rate according to the current limiting frequency protection value and the phase current amplitude, and calculating a voltage limiting amplitude attenuation rate according to the voltage limiting threshold value and the modulation voltage amplitude; superimposing the current limiting amplitude attenuation rate to the output of a first proportional integral controller in a speed control module to obtain a quadrature axis current instruction Iq* and a direct axis current instruction Id*; superimposing the voltage limiting amplitude attenuation rate to the output of a second proportional integral controller in a current control module to obtain a quadrature axis voltage instruction Vq* and a direct axis voltage instruction Vd*; performing Park inverse transformation and modulation on the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* to obtain a three-phase voltage output for driving the motor, and controlling the permanent magnet synchronous motor according to the three-phase voltage; wherein when the current limiting amplitude attenuation rate is less than 1 or the voltage limiting amplitude attenuation rate is less than 1, the speed instruction in the speed control module is less than or equal to the observed speed; wherein the method further comprises: if the current limiting amplitude attenuation rate is less than the voltage limiting amplitude attenuation rate, superimposing the current limiting amplitude attenuation rate to the speed control module; if the current limiting amplitude attenuation rate is greater than the voltage limiting amplitude attenuation rate, superimposing the voltage limiting amplitude attenuation rate to the speed control module.

2. The current and voltage adaptive control method of a permanent magnet synchronous motor according to claim 1, wherein, The method further comprises: limiting the speed control module through a first limiting link to ensure the stability of a position observer; limiting the current limiting amplitude attenuation rate through a second limiting link to achieve rapid following of the output current when a load suddenly changes; limiting the voltage limiting amplitude attenuation rate through a third limiting link to achieve rapid following of the output voltage when a voltage suddenly changes.

3. The current and voltage adaptive control method of a permanent magnet synchronous motor according to claim 2, wherein, The calculation formula of the current limiting amplitude decay rate is: Ratio cur =Ilim / Im*; wherein, Ratio cur is the current limiting attenuation rate, Ilim is the current limiting protection value, Im* is the phase current amplitude, the phase current amplitude , Id* is the direct axis current command, Iq* is the quadrature axis current command; The calculation formula of the voltage amplitude attenuation rate is: Ratio sat =Vsat / Vm*; wherein, Ratio sat is the voltage saturation rate, Vsat is the voltage saturation threshold, Vm* is the modulation voltage amplitude, said modulation voltage amplitude Vd* is the direct-axis voltage command, and Vq* is the quadrature-axis voltage command.

4. A current voltage adaptive control device of a permanent magnet synchronous motor, characterized by, The device comprises: an acquisition module configured to acquire a current limiting frequency protection value, a phase current amplitude, a voltage limiting threshold value and a modulation voltage amplitude of a permanent magnet synchronous motor; a calculation module configured to calculate a current limiting amplitude attenuation rate according to the current limiting frequency protection value and the phase current amplitude, and calculate a voltage limiting amplitude attenuation rate according to the voltage limiting threshold value and the modulation voltage amplitude; an adaptive module configured to superimpose the current limiting amplitude attenuation rate to the output of a first proportional integral controller in a speed control module to obtain a quadrature axis current instruction Iq* and a direct axis current instruction Id*, and superimpose the voltage limiting amplitude attenuation rate to the output of a second proportional integral controller in a current control module to obtain a quadrature axis voltage instruction Vq* and a direct axis voltage instruction Vd*; a control module configured to perform Park inverse transformation and modulation on the quadrature axis voltage instruction Vq* and the direct axis voltage instruction Vd* to obtain a three-phase voltage output for driving the motor, and control the permanent magnet synchronous motor according to the three-phase voltage; wherein when the current limiting amplitude attenuation rate is less than 1 or the voltage limiting amplitude attenuation rate is less than 1, the speed instruction in the speed control module is less than or equal to the observed speed; wherein the device further comprises a forward feedback module configured to: If the current limit attenuation rate is less than the voltage limit attenuation rate, the current limit attenuation rate is superimposed into the speed control module; If the current limit attenuation rate is greater than the voltage limit attenuation rate, the voltage limit attenuation rate is superimposed into the speed control module.

5. The current and voltage adaptive control device of the permanent magnet synchronous motor according to claim 4, wherein, The device further comprises a limiting module for: The speed control module is limited by a first limiting link to ensure the stability of the position observer; the current limit attenuation rate is limited by a second limiting link to realize the rapid following of the output current when the load suddenly changes; and the voltage limit attenuation rate is limited by a third limiting link to realize the rapid following of the output voltage when the voltage suddenly changes.

6. The current and voltage adaptive control device of the permanent magnet synchronous motor according to claim 5, wherein, The calculation formula of the current limiting amplitude decay rate is: Ratio cur =Ilim / Im*; wherein, Ratio cur is the current limiting damping rate, Ilim is the current limiting protection value, Im* is the phase current amplitude, the phase current amplitude , Id* is the direct axis current command, Iq* is the quadrature axis current command; The calculation formula of the voltage amplitude attenuation rate is: Ratio sat =Vsat / Vm*; wherein, Ratio sat is the voltage saturation rate, Vsat is the voltage saturation threshold, Vm* is the modulation voltage amplitude, said modulation voltage amplitude Vd* is the direct-axis voltage command, and Vq* is the quadrature-axis voltage command.

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