A motor control device, a control method, and a turnstile system

Abstract

The present application discloses a motor control device, including: a forward path including a position reference unit for generating a motor rotation position reference signal, a position control unit for controlling the motor rotation position, a speed control unit for controlling the motor speed, and a current control unit for controlling the motor current, which are connected in sequence; and a feedback path including a first feedback unit for feedbacking the current rotation position and current rotation speed of the motor, a second feedback unit for feedbacking the current motor current, and a feedforward unit for selectively compensating the motor current. The feedforward unit outputs a selectively compensating current signal according to the position error signal from the position control unit. The current control unit outputs a control signal for controlling the motor according to the selectively compensating current signal, a first current reference signal from the speed control unit, and a current feedback signal from the second feedback unit. The present application is beneficial to improving the stability and anti-interference ability of reaching the position.

Description

Technical Field

[0001] The present invention relates to the field of motor control, and in particular, to a motor control method, device, and turnstile system. Background Art

[0002] In the actual application of motor drive, in order to avoid wear of the speed reducer and faults caused by the connection between the speed reducer and the motor, and to increase the reliability of the motor drive, the output shaft of the motor can be directly connected to the driven mechanism through a flexible coupling. This motor drive method without a speed reduction mechanism greatly improves the cost performance compared with the existing motor drive method with a speed reducer. The overall structure is compact, the power transmission efficiency is high, the service life of the motor can be significantly increased, and at the same time, the noise generated by the motor operation can be greatly reduced, having a broad market prospect.

[0003] However, due to the cancellation of the speed reducer, problems such as serious mismatch between the load inertia (the inertia of the load reflected on the output shaft of the motor) and the motor rotor inertia (the inertia of the motor body), and low stiffness of the mechanical transmission mechanism are brought about, resulting in a relatively long transmission or reaction time of the mechanical transmission mechanism, and further affecting the rapidity of the motor response and the stability of reaching the position. That is to say, due to the mismatch between the fast response of the rotational position control and the slow response of the mechanical transmission, the motor operation is finally unstable, directly manifested as inertial jitter when the driven mechanism reaches the target position. Summary of the Invention

[0004] The present invention provides a motor control method to improve the stability when the motor drives the driven mechanism to reach the target position.

[0005] The present invention provides a motor control device, which includes:

[0006] A forward channel including a position reference unit connected in sequence for generating a motor rotation position reference signal, a position control unit for controlling the motor rotation position, a speed control unit for controlling the motor speed, and a current control unit for controlling the motor current, and

[0007] A feedback channel including a first feedback unit for feedbacking the current rotation position and current rotation speed of the motor, a second feedback unit for feedbacking the current current of the motor, and a feedforward unit for selectively compensating the motor current,

[0008] Wherein,

[0009] The position reference unit generates a position reference signal for controlling the motor rotation position according to the set target position,

[0010] The position control unit outputs a rotational speed reference signal for controlling the rotational speed of the motor and a position error signal according to a position reference signal from the position reference unit and a position feedback signal from the first feedback unit. The position error signal is used to represent the position error between the target rotational position and the current rotational position.

[0011] The rotational speed control unit outputs a first current reference signal according to the rotational speed reference signal from the position control unit and a rotational speed feedback signal from the first feedback unit.

[0012] The feedforward unit outputs a selective compensation current signal according to the position error signal from the position control unit.

[0013] The current control unit outputs a control signal for controlling the motor according to the selective compensation current signal, the first current reference signal, and a current feedback signal from the second feedback unit.

[0014] Preferably, the feedforward unit includes:

[0015] A differentiation module, which outputs the selective compensation current signal as zero when the position error signal is greater than a set compensation threshold, and differentiates the position error signal to obtain a differentiation result when the position error signal is not greater than the set compensation threshold. The differentiation result is used as the selective compensation current signal.

[0016] Preferably, the feedforward unit further includes:

[0017] A compensation coefficient module, which corrects the differentiation result from the differentiation module according to a compensation coefficient, and the corrected differentiation operation result is used as the selective compensation current signal, where the compensation coefficient is determined according to the load inertia;

[0018] The signal after superimposing the selective compensation current signal and the first current reference signal is used as a second current reference signal and input to the current control unit;

[0019] The current control unit includes a first proportional-integral controller,

[0020] wherein,

[0021] The first proportional-integral controller performs proportional integration on the difference between the second current reference signal and the current feedback signal and outputs it as the control signal.

[0022] Preferably, the corrected differentiation operation result is: the product of the differentiation result and the compensation coefficient;

[0023] When the change rate of the position error signal is greater than 0, the selective compensation current positively compensates the first current; when the change rate of the position error signal is less than 0, the selective compensation current negatively compensates the first current; when the change rate of the position error signal is equal to 0, the first current is not compensated.

[0024] Preferably, the motor is a brushless DC motor.

[0025] The selective compensation current signal is a torque current signal for torque current compensation.

[0026] The current control unit is a current control module in a vector control module for motor field-oriented control. The current control module outputs a first torque reference voltage in a two-phase rotating coordinate system according to the selective compensation current signal, the first current reference signal, and the torque current feedback signal from the second feedback unit; and outputs a first excitation reference voltage in a two-phase rotating coordinate system according to the excitation current feedback signal from the second feedback unit and a given excitation current reference signal.

[0027] Preferably, the second feedback unit is a current feedback module in the vector control module, and the current feedback module includes a first transformation function.

[0028] Wherein,

[0029] The first transformation function performs a coordinate transformation on the sampled three-phase current signal according to the angle feedback signal for characterizing the current rotation angle from the first feedback unit, and outputs the torque current feedback signal and the excitation current feedback signal.

[0030] Preferably, the vector control module further includes a second transformation function module. The second transformation function module transforms the first torque reference voltage and the first excitation reference voltage from the current control module into a second reference voltage in a two-phase stationary coordinate system according to the angle feedback signal.

[0031] Preferably, the control unit further includes a pulse width modulation unit.

[0032] The pulse width modulation unit generates a pulse width modulation wave from the second reference voltage from the second transformation function module. The pulse width modulation wave is used to provide a control signal for the operation of an inverter circuit, where the inverter circuit is used to invert a DC power supply into an AC power supply and supply it to the brushless DC motor.

[0033] Preferably, the first feedback unit includes: an encoder for obtaining the rotational position and speed of the motor, a first sampling circuit for obtaining the output signal from the encoder, and a position and speed calculation module for calculating the rotational position and speed of the motor.

[0034] Wherein,

[0035] The position and speed calculation module determines the position feedback signal according to the sampling signal representing the current rotational position from the first sampling circuit; determines the speed feedback signal according to the sampling signal and the corresponding time, and determines the angle feedback signal according to the sampling signal.

[0036] Preferably, the first feedback unit further includes a first filtering circuit, which filters the speed feedback signal from the position and speed calculation module and then outputs it to the speed control unit.

[0037] Preferably, the second feedback circuit further includes a second sampling circuit for sampling the three-phase current of the DC brushless motor and the DC power supply voltage. The second sampling circuit inputs the sampled current signal into the first transformation function, and inputs the sampled DC power supply voltage and the sampled current signal into the fault detection unit.

[0038] Preferably, the fault detection unit includes: a second filtering circuit and a fault detection module.

[0039] Wherein,

[0040] The second filtering circuit filters the DC power supply voltage signal and the sampled current signal sampled by the second sampling circuit and then inputs them into the fault detection module.

[0041] The fault detection module performs motor fault detection according to the input signals.

[0042] Preferably, the current control module includes a second proportional-integral controller and a third proportional-integral controller.

[0043] Wherein,

[0044] The second proportional-integral controller performs proportional integration on the difference between the torque current reference signal and the torque current feedback signal and outputs it as the first torque reference voltage signal.

[0045] The third proportional-integral controller performs proportional integration on the difference between the field current reference signal and the field current feedback signal and outputs it as the first field reference voltage signal.

[0046] Preferably, the motor is connected to the driven mechanism through a flexible coupling, or the load inertia of the motor does not match the motor inertia, or the motor has no reduction mechanism.

[0047] The position reference unit includes a ramp function module and a third filter circuit. After the target position signal is processed by the ramp function module and the third filter circuit in sequence, the position reference signal is output. The target position signal corresponds to the target position of the driven mechanism or the target rotation position of the motor.

[0048] The compensation threshold is determined according to the position error between the current position and the target position of the driven mechanism.

[0049] Preferably, the position error signal is the difference between the position reference signal and the position feedback signal.

[0050] The position control unit includes a proportional controller.

[0051] Wherein, the proportional controller processes the position error signal according to a set ratio and outputs it as the speed reference signal.

[0052] Preferably, the speed control unit includes a fourth proportional-integral controller.

[0053] Wherein,

[0054] The fourth proportional-integral controller performs proportional integration on the difference between the speed reference signal and the speed feedback signal and outputs it as the first current reference signal.

[0055] The present invention provides a motor control method, which includes:

[0056] Obtaining a position feedback quantity for characterizing the current rotation position of the motor, a speed feedback quantity for characterizing the current speed of the motor, and a current feedback quantity for characterizing the current current of the motor.

[0057] Determining a position reference quantity for controlling the rotation position of the motor according to a set target position.

[0058] Determining a speed reference quantity for controlling the speed of the motor according to the position feedback quantity and the position reference quantity.

[0059] Determining a first current reference quantity according to the speed feedback quantity and the speed reference quantity.

[0060] Determining a selective compensation current quantity according to a position error quantity for characterizing the position error between the target rotation position and the current rotation position.

[0061] Determine a control quantity for controlling the motor according to the selective compensation current quantity, the first current reference quantity, and the current feedback quantity.

[0062] Preferably, determining the selective compensation current quantity according to the position error quantity for characterizing the position error between the target rotation position and the current rotation position includes:

[0063] When the position error is greater than a set compensation threshold, determine that the selective compensation current quantity is zero; when the position error is not greater than the set compensation threshold, perform a differential process on the position error to obtain the selective compensation current quantity;

[0064] The compensation threshold is determined according to the position error between the current position and the target position of the driven mechanism.

[0065] Preferably, determining the selective compensation current quantity according to the position error quantity for characterizing the position error between the target rotation position and the current rotation position further includes:

[0066] Correct the selective compensation current quantity according to a compensation coefficient to obtain a corrected selective compensation current quantity.

[0067] Wherein, the compensation coefficient is determined according to the load inertia.

[0068] Preferably, determining the control quantity for controlling the motor according to the selective compensation current quantity, the first current reference quantity, and the current feedback quantity for characterizing the current of the motor includes:

[0069] Superimpose the selective compensation current and the first current reference quantity to obtain a second current reference quantity.

[0070] Subtract the current feedback quantity from the second current reference quantity to obtain the control quantity.

[0071] Preferably, the motor is a brushless DC motor.

[0072] Subtracting the current feedback quantity from the second current reference quantity to obtain the control quantity includes:

[0073] Use the second current reference quantity as the torque current given quantity and input it into the vector control module for controlling the brushless DC motor.

[0074] Perform vector pulse width modulation on the second voltage reference quantity output by the vector control module to obtain a pulse width modulation wave for controlling the inverter circuit.

[0075] Wherein, the inverter circuit is used to invert the DC power supply into an AC power supply for supplying power to the motor.

[0076] Preferably, obtaining the position feedback quantity for characterizing the current rotation position of the motor, the speed feedback quantity for characterizing the current speed of the motor, and the current feedback quantity for characterizing the current current of the motor includes:

[0077] Determining the position feedback quantity according to the current position information from the encoder,

[0078] Determining the speed feedback quantity according to the current position information and its corresponding time,

[0079] Determining the angle feedback quantity for characterizing the current rotation angle according to the current position information, and providing it to the vector control module, so that the vector control module determines the torque current feedback quantity for characterizing the current torque current and the excitation current feedback quantity for characterizing the current excitation current according to the sampled AC power supply current.

[0080] Preferably, the method further includes:

[0081] Performing motor fault detection according to the sampled voltage of the DC power supply and the sampled current of the AC power supply.

[0082] The present invention provides a turnstile system, including a motor for driving a blocking part and any one of the motor control devices.

[0083] The present invention provides a computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by a processor, the steps of any one of the motor control methods are implemented.

[0084] In the embodiment of the present application, according to the position error, the compensation current is selectively increased, so that the control quantity for controlling the motor increases, thereby suppressing the jitter after reaching the position and external torque interference by increasing the system damping ratio, which is beneficial to improving the stability and anti-interference ability of the motor or the driven mechanism when reaching the position, and has strong adaptability to the situation where the load inertia does not match the motor inertia. Description of the Drawings

[0085] Figure 1 It is a schematic diagram of a control device for a motor without a deceleration mechanism in an embodiment of the present application.

[0086] Figure 2 It is a schematic diagram of a control device for a DC brushless motor in an embodiment of the present application.

[0087] Figure 3 It is a schematic diagram of a feedforward unit in an embodiment of the present application.

[0088] Figure 4 It is a schematic flowchart of a motor control method in an embodiment of the present application.

[0089] Figure 5 Another schematic diagram of the control device according to the embodiment of the present application.

[0090] Figure 6 Another schematic diagram of the control device according to the embodiment of the present application.

[0091] Figure 7 A schematic diagram of the turnstile system according to the embodiment of the present application.

[0092] Figure 8 A schematic diagram of the experimental comparison waveform of the position control loop before and after adding the present optimization scheme.

[0093] Figure 9 It is a Figure 8 Waveform diagram after magnifying the marked position 1 in

[0094] Figure 10 It is a Figure 8 Waveform diagram after magnifying the marked position 2 in

[0095] Figure 11 A schematic diagram of the waveform of the position signal after suddenly applying a disturbance when the turnstile wing is in a stationary state after reaching the position before optimization in the embodiment of the present application.

[0096] Figure 12 A schematic diagram of the position waveform after suddenly applying a disturbance when the turnstile wing is in a stationary state after reaching the position after optimization in the embodiment of the present application. Detailed implementation manners

[0097] In order to make the purpose, technical means and advantages of the present application clearer, the following further describes the present application in detail with reference to the accompanying drawings.

[0098] In the embodiment of the present application, a feedforward unit for selectively compensating the motor current is added to the forward channel, so as to selectively increase the current value of the motor to increase the system damping ratio, thereby suppressing the jitter after the driven mechanism reaches the target position (in place).

[0099] Refer to Figure 1 as shown in Figure 1 A schematic diagram of the control device of the motor without a deceleration mechanism according to the embodiment of the present application. The control device includes:

[0100] A forward channel including a position reference unit connected in sequence for generating a motor rotation position reference signal, a position control unit for controlling the motor rotation position, a speed control unit for controlling the motor speed, and a current control unit for controlling the motor current, and

[0101] A feedback channel includes a first feedback unit for feedbacking the current rotation position and current rotation speed of the motor, a second feedback unit for feedbacking the current current of the motor, and a feedforward unit for selectively compensating the motor current.

[0102] Among them,

[0103] The position reference unit generates a position reference signal for controlling the rotation position of the motor according to the set target position.

[0104] The position control unit outputs a rotation speed reference signal for controlling the rotation speed of the motor and a position error signal according to the position reference signal from the position reference unit and the position feedback signal from the first feedback unit. This position error signal is used to characterize the position error between the target rotation position and the current rotation position.

[0105] The rotation speed control unit outputs a first current reference signal according to the rotation speed reference signal from the position control unit and the rotation speed feedback signal from the first feedback unit.

[0106] The feedforward unit outputs a selectively compensating current signal according to the position error signal from the position control unit.

[0107] The current control unit outputs a control signal for controlling the motor according to the selectively compensating current signal, the first current reference signal, and the current feedback signal from the second feedback unit.

[0108] In the embodiment of the present application, the selectively compensating current signal is used to selectively increase the input current of the current control unit, thereby improving the stability of the motor driving the driven mechanism to reach the position.

[0109] To facilitate the understanding of the embodiment of the present application, the following takes the motor control of a direct-drive swing gate in a turnstile system for channel blocking as an example for illustration. It should be understood that the embodiment of the present application is not limited to the turnstile system, nor is it limited to the swing gate. Any motor without a reduction mechanism or motor control with a mismatch between the load inertia and the motor inertia is applicable.

[0110] The direct-drive swing gate used in the turnstile mechanism usually eliminates the speed reducer and adopts a brushless DC motor (BLDC) with a relatively low rated speed and a relatively large rated torque. This brushless DC motor is a permanent magnet synchronous motor with a trapezoidal wave air-gap magnetic field. The rotation position, rotation angle, and speed of the motor rotor are fed back through an encoder coaxial with the motor, such as a compound incremental magnetic encoder. The magnitude of the motor current is fed back through a sampling circuit, such as a sampling resistor. Using the above feedback quantities and adopting a vector control (FOC, Field Oriented Control) method for field-oriented control, the current, speed, and rotation position of the motor are controlled. Then, the motor directly drives the door wing load through a coupling to realize a series of actions such as opening and closing the turnstile door.

[0111] Although the direct-drive technology used in the turnstile mechanism has the advantages of high operating efficiency, good reliability of the mechanism, and reduced noise generated during the operation of the mechanism, the application of direct-drive technology in turnstile scenarios also brings the following problems:

[0112] 1. The encoder measures the rotation position and speed of the motor, rather than the position and speed of the door wing load.

[0113] 2. Since there is no speed reducer, the motor is directly connected to the door wing load through a mechanical transmission mechanism. Due to the too large load inertia ratio (the ratio of load inertia to motor inertia) and insufficient rigidity of the mechanical transmission mechanism, instability problems occur during the point-to-point position control process, which is directly manifested as inertial jitter during positioning.

[0114] 3. The motor is usually subject to torque disturbances from the motor itself (such as cogging torque, harmonic torque) and external loads (such as load torque, friction torque). In the case of a traditional motor with a speed reducer, after passing through a reduction mechanism such as a gearbox, the torque disturbance will be attenuated by a certain proportion. In the case of direct drive, since there is no reduction mechanism, all load torques, moments of inertia, and torque disturbances will be directly applied to the motor side without attenuation. Although the influence of some disturbances can be ignored at medium and high speeds, for low-speed and even ultra-low-speed operating conditions, the stability and performance of the motor will be severely affected, thereby reducing the control accuracy and performance, and increasing the control difficulty of the motor to a certain extent. Therefore, higher requirements are put forward for the anti-disturbance and stability of the motor at low speeds and even ultra-low speeds.

[0115] 4. When the mechanical transmission mechanism is fixed, it is very difficult to change the mechanical rigidity and reduce the load inertia. If the gain of the position control unit is reduced, the operating speed can be reduced, thereby reducing the jitter amplitude and improving the stability. However, this will prolong the movement time of the door wing, which conflicts with the generally required short opening and closing time of the turnstile. Therefore, for the application of direct drive technology in the turnstile system, the traditional proportional-integral (PI) control is difficult to balance the system dynamic characteristics and steady-state performance. It is necessary to improve the traditional PI controller to solve the jitter problem in place and improve the system stability on the premise of high engineering application value.

[0116] To improve the stability of the direct drive swing turnstile in place and avoid jitter after the door wing reaches the target position during the process of the motor driving the door wing to move to the target position due to the mismatch of the load motor inertia ratio, the embodiments of this application have improved the control method and control device of the DC brushless motor.

[0117] See Figure 2 shown in Figure 2 is a schematic diagram of a control device for a DC brushless motor according to an embodiment of this application. The control device includes: an FOC module, a position reference unit for generating a motor rotation position reference signal, a position control unit for controlling the motor rotation position, a speed control unit for controlling the motor speed, and a first feedback unit for respectively outputting a position feedback signal Pos for characterizing the current rotation position of the motor fd and outputting a speed feedback signal n for characterizing the current speed of the motor fd and a first feedback unit for outputting an angle feedback signal for characterizing the current rotation angle of the motor, and a feedforward unit for selectively compensating the motor current.

[0118] Among them,

[0119] the FOC module includes: a second feedback unit for feeding back the current current of the motor, a current control module, a first transformation function module, and a second transformation function module. Among them, the current control module belongs to a current control unit, and the second transformation function module belongs to the second feedback unit.

[0120] The position reference unit, the position control unit, the speed control unit, the current control module, and the first transformation function module are sequentially connected to form a forward channel.

[0121] The feedforward unit, the first feedback unit, and the second transformation function module form a feedback channel.

[0122] As an example, in the forward channel:

[0123] The position reference unit includes a ramp function (RAMP) module and a first filter circuit. The target position signal is processed by the ramp function (RAMP) module and the first filter circuit in sequence and used as the position reference signal Pos refInput to the position control unit, where the first filter circuit is used to smooth the input signal, and the target position signal can be obtained through the position command Pos indicating the target rotation position of the motor. The target position can be the target rotation position of the motor or the target position required by the driven mechanism, for example, the target position of the door wing. targ The target position can be the target rotation position of the motor or the target position required by the driven mechanism, for example, the target position of the door wing.

[0124] The position control unit includes a proportional controller (P). The position control unit subtracts the position feedback signal Pos from the input position reference signal Pos ref from the first feedback unit fd to obtain a position error signal Pos error . After passing through the proportional controller, the position error signal outputs a speed reference signal n ref . Among them, the position error signal characterizes the position error between the target position and the current position.

[0125] The speed control unit includes a first proportional-integral controller (PI). The speed control unit subtracts the speed feedback signal n from the input speed reference signal n ref from the first feedback unit fd and, after passing through the first proportional-integral controller, outputs a first current reference signal i q '.

[0126] The feedforward unit outputs a selective compensation current signal i qcmp according to the position error signal from the position control unit.

[0127] The selective compensation current signal i qcmp is superimposed on the first current reference signal i q ' and then input to the current control module in the FOC module. Among them, the superimposed current signal serves as a second current reference signal i qref .

[0128] In the FOC module, the current control module subtracts the torque current feedback signal i q and the excitation current feedback signal i d from the first transformation function module, respectively, from the input second current reference signal i qref and the given excitation current reference id ref . After passing through the third proportional-integral controller and the fourth proportional-integral controller respectively, a first torque reference voltage u q and a first excitation reference voltage u d in the two-phase rotating coordinate system are obtained. The second transformation function module, such as the inverse Park (IPARK) function, according to the angle feedback signal, transforms the first torque reference voltage u q and the first excitation reference voltage u dAfter performing transformations respectively, the second reference voltages u α and u β in the two-phase stationary coordinate system are obtained and output to the pulse width modulation unit, for example, the space vector pulse width modulation (SVPWM) unit. The reference voltage generates a pulse width modulation wave (PWM) after passing through the pulse width modulation unit. This pulse width modulation wave is used to control the conduction and turn-off of the thyristors in the inverter circuit. The number of paths of the pulse width modulation wave depends on the number of thyristors in the inverter circuit. For example, in this embodiment, it is six paths of pulse width modulation waves. The inverter circuit is used to invert the DC power supply into an AC power supply, for example, three-phase alternating current, and this three-phase AC power supply provides the working power for the DC brushless motor, thereby driving the motor to rotate to the given target rotation position Pos targ .

[0129] The second feedback unit includes a second transformation function module and a second sampling circuit. The second sampling circuit samples the three-phase current of the DC brushless motor and the DC power supply voltage. The second transformation function module performs coordinate transformation on the sampled three-phase current signals according to the angle feedback signal from the first feedback unit and outputs the torque current feedback signal i q and the field current feedback signal i d . Among them, the second transformation function module includes the Clarke function and the Park function, and the angle feedback signal is input to the Park function

[0130] The first feedback unit includes: an encoder for collecting the motor rotation position signal, a first sampling circuit for sampling the output signal of the encoder, a position and speed calculation module for calculating the position feedback signal Pos fd , the angle feedback signal, and the speed feedback signal n ref , and a first filtering circuit. Among them, the motor rotation position signal from the encoder is sampled by the first sampling circuit to obtain a sampling signal for characterizing the current rotation position. This sampling signal is input to the position and speed calculation module. The position and speed calculation module determines the position feedback signal Pos fd according to the input sampling signal, determines the speed feedback signal n ref according to the sampling signal and the corresponding time, and determines the angle feedback signal according to the sampling signal. In order to improve the quality of the motor speed feedback signal, the speed feedback signal n ref output by the position and speed calculation module is output after being processed by the first filtering circuit

[0131] The control device further includes a fault detection unit. The fault detection unit includes: a second filtering circuit and a fault detection module. The second filtering circuit filters the DC power supply voltage signal and the sampled current signal sampled by the second sampling circuit and inputs them to the fault detection module. The fault detection module performs motor fault detection according to the input signals

[0132] As an example, such as Figure 2 in, the second filter circuit filters the DC power supply voltage signal u sampled by the second sampling circuit dc and at least two-phase current signals among the sampled three-phase current signals, and then inputs the filtered signals to the fault detection module.

[0133] The above filter circuits are all low-pass filter circuits.

[0134] Referring to Figure 3 as shown Figure 3 is a schematic diagram of a feedforward unit according to an embodiment of the present application. The feedforward unit includes a differentiator module and a compensation coefficient module,

[0135] wherein:

[0136] When the position error signal is greater than the set compensation threshold, the differentiator module outputs a selective compensation current signal of zero. When the position error signal is not greater than the compensation threshold, the differentiator module differentiates the position error signal to obtain a differentiation result, which can be used as the selective compensation current signal. Differentiation can reflect the rate of change of the position error signal and does not affect the constant steady-state error of the system, which is equivalent to increasing the damping ratio of the system.

[0137] In order to make the selective compensation current signal match the load inertia, the compensation coefficient module corrects the differentiation result according to the compensation coefficient, and uses the corrected differentiation result as the selective compensation current signal.

[0138] The differentiator module may include a comparator and a differentiator, and the compensation coefficient module may include a multiplier. The comparator compares the position error signal with the compensation threshold. If the position error signal is greater than the compensation threshold, the output stops. If the position error signal is not greater than the compensation threshold, the position error signal is input to the differentiator, and the output signal of the differentiator is input to the multiplier, and the multiplier outputs the selective compensation current signal. Among them, the proportional value of the multiplier is the compensation coefficient.

[0139] The compensation coefficient can be selected with different values according to different door wing load inertias. Generally, a larger load inertia requires a larger damping ratio, so a larger compensation coefficient is selected; a smaller load inertia requires a smaller damping ratio, so a smaller compensation coefficient is selected. The compensation threshold can be a set compensation angle threshold.

[0140] In this embodiment, by differentiating the position error, the direction of the position change can be detected in advance, and the torque current is corrected in advance by using the detected differential quantity of the position change, which is beneficial to reaching the steady-state value as soon as possible. In this embodiment, differential control is not added at the very beginning of the movement of the turnstile door wing, avoiding the extension of the opening time, and differential control is added when the door wing is about to reach the position, ensuring the rapidity of the operation of the turnstile door wing.

[0141] See Figure 4 as shown Figure 4 which is a schematic flowchart of a motor control method according to an embodiment of the present application. The method includes:

[0142] Step 401, obtaining a position feedback quantity Pos fd , a rotational speed feedback quantity n fd , and a current feedback quantity.

[0143] As an example, according to the current position information from the encoder, the position feedback quantity is determined.

[0144] According to the current position information and its corresponding time, the rotational speed feedback quantity is determined.

[0145] According to the sampled current at present, the current feedback quantity is determined.

[0146] Furthermore, according to the current position information, an angle feedback quantity is determined and provided to the vector control module.

[0147] Step 402, according to the set target position Pos targ , determining a position reference quantity Pos ref for controlling the rotational position of the motor.

[0148] As an example, the target position can be the target position required by the driven mechanism, for example, the target position required by the door wing, or the rotational target position required by the motor rotation, and the two can be converted through calibration.

[0149] Step 403, according to the position feedback quantity Pos fd representing the current rotational position of the motor ref , and the position reference quantity Pos ref , determining a rotational speed reference quantity n ref

[0150] As another example, in the control of a brushless DC motor, the position feedback quantity Pos fd is obtained through an encoder.

[0151] Step 404, according to the rotational speed feedback quantity n fd representing the current rotational speed of the motor, determine the first current reference quantity i q ′,

[0152] Step 405, according to the position error quantity Pos used to characterize the position error between the target rotation position and the current rotation position error , determine the selective compensation current quantity i qcmp ,

[0153] As an example, during the opening or closing movement of the direct-drive swing gate wing, the position reference quantity Pos of the motor ref and the position feedback quantity Pos fd are subtracted to obtain the position error quantity Pos error , which is expressed by the mathematical formula as:

[0154] Pos error = Pos ref - Pos fd

[0155] The absolute value of the position error quantity Pos error is compared with the compensation angle threshold θ:

[0156] If it is greater than the compensation angle threshold θ, determine that the selective compensation current quantity i qcmp is zero,

[0157] If it is not greater than the compensation angle threshold θ, differentiate the position error quantity Pos error The compensation angle threshold can be determined according to the position error between the current position and the target position of the driven mechanism.

[0158] The above comparison process can be expressed by the mathematical formula as:

[0159]

[0160] Among them, dPos error / dt reflects the rate of change of the position error quantity and does not affect the constant steady-state error of the system, which is equivalent to increasing the damping ratio of the system.

[0161] Multiply the value diff(Pos) obtained after differential processing by the compensation coefficient k to obtain the selective compensation current quantity i qcmp , which is expressed by the mathematical formula as:

[0162] i qcmp = k × diff(Pos)

[0163] The compensation coefficient k can be selected with different values according to different gate wing load inertias. Generally, a large load inertia requires a large damping ratio, so a larger k value is selected; a small load inertia requires a small damping ratio, so a smaller k value is selected.

[0164] Step 406: Determine the control quantity for controlling the motor according to the selective compensation current i qcmp , the first current reference quantity i q ', and the current feedback quantity used to characterize the current of the motor at present.

[0165] As an example, add the selective compensation current quantity i qcmp to the first current reference quantity i q ' to obtain the second current reference quantity i qref , which is expressed by the mathematical formula as:

[0166] i qref = i qcmp + i q '

[0167] Wherein, when the change rate of the position error signal is greater than 0, the selective compensation current positively compensates the first current; when the change rate of the position error signal is less than 0, the selective compensation current negatively compensates the first current; when the change rate of the position error signal is equal to 0, the selective compensation current does not compensate the first current.

[0168] As an example, in the control of a brushless DC motor, use the second current reference quantity as the torque current reference quantity and input it to the FOC module, and subtract it from the torque current feedback quantity i q to obtain the given torque current quantity of the current control module in the FOC module.

[0169] Step 407: Perform space vector pulse width modulation on the second voltage reference quantity output by the FOC module to obtain the pulse width modulation wave for controlling the inverter circuit.

[0170] As an example, this method may further include performing motor fault detection according to the sampled DC power supply voltage u dc and at least two-phase currents among the sampled three-phase current signals.

[0171] As another example, the functions of the above FOC module can be realized by the following steps:

[0172] Step 501: Obtain the angle feedback quantity and the three-phase AC current feedback quantity.

[0173] Step 502: Perform CLARKE function transformation on the three-phase AC current feedback quantity to obtain the currents i α and i β in the two-phase stationary coordinate system. According to the angle feedback quantity, rotate the currents i α , i βPerform the PARK function transformation to obtain the current feedback quantities \(i\) q and \(i\) d ,

[0174] Step 502: Subtract the second current reference quantity \(i\) qref from the current feedback quantity \(i\) q to obtain the given torque current quantity. Subtract the exciting current reference quantity from the current feedback quantity \(i\) d to obtain the given exciting current quantity;

[0175] Step 503: Perform proportional integration on the given torque current quantity and the given exciting current quantity respectively to obtain the first torque voltage quantity and the first exciting voltage quantity,

[0176] Step 504: According to the angle feedback quantity, perform the IPARK function transformation on the first torque voltage quantity \(u\) q and the first exciting voltage quantity \(u\) d to obtain the second voltage reference quantities \(u\) α and \(u\) β ,

[0177] Step 505: According to the second voltage reference quantities \(u\) α and \(u\) β , perform vector pulse width modulation to obtain the pulse width modulation wave for controlling the inverter circuit. See Figure 5 shown Figure 5 is another schematic diagram of the control device according to the embodiment of the present application. The control device includes a memory, a processor, and an FOC module. The memory stores a computer program, and the processor executes the computer program to implement steps 401-407 in the above motor control method. The first current reference signal and the angle feedback signal output by the processor are input into the FOC module, and the FOC module outputs a second reference voltage to the processor.

[0178] See Figure 6 shown Figure 6 is another schematic diagram of the control device according to the embodiment of the present application. The control device includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement steps 401-406 and steps 501-505 in the above motor control method.

[0179] The memory may include a random access memory (RAM), or may also include a non-volatile memory (NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located far from the aforementioned processor.

[0180] The above-mentioned processor may be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc.; it may also be a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field-Programmable Gate Array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

[0181] An embodiment of the present invention also provides a computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by a processor, the steps of the above control method are implemented.

[0182] See Figure 7 as shown in Figure 7 a schematic diagram of a turnstile system according to an embodiment of the present application. The turnstile system includes a motor for driving a blocking part and a motor control device for controlling the motor.

[0183] For ease of understanding the technical effects of the embodiments of the present application, see Figure 8 as shown in Figure 8 the experimental comparison waveforms of the position control loop before and after adding the present optimization scheme, corresponding to the test results of the left and right door opening and closing of the direct-drive swing turnstile. It can be seen from the figure that when the scheme of the embodiments of the present application is not enabled, the actual position Pos fd of the door wing has a jitter phenomenon when approaching the target reference position Pos ref while when the embodiments of the present application are enabled, the actual position Pos fd has significantly eliminated the jitter phenomenon when approaching the target reference position Pos ref

[0184] See Figure 9 as shown in Figure 9 is the waveform diagram after magnifying the marked position 1 in Figure 8 It can be seen that the in-place jitter phenomenon is obvious before optimization.

[0185] See Figure 10 as shown in Figure 10 is the waveform diagram after magnifying the marked position 2 in Figure 8 It can be seen that the in-place jitter phenomenon is significantly weakened after optimization.

[0186] See Figure 11 as shown in Figure 11 ​Before optimization in the embodiment of the present application, when the wing of the turnstile gate is in a static state after reaching the position, the waveform of the position signal after a sudden disturbance is applied. It can be seen that the anti-disturbance ability of the wing of the turnstile gate before optimization is poor, and the time to return to the stable state is long;

[0187] See Figure 12 as shown Figure 12 In the embodiment of the present application after optimization, when the wing of the turnstile gate is in a static state after reaching the position, the position waveform after a sudden disturbance is applied. It can be seen that the anti-disturbance ability of the wing of the turnstile gate after optimization is strong and it can quickly return to the stable state.

[0188] In this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0189] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A motor control device, characterized in that, The device includes: a forward channel including a position reference unit for generating a motor rotation position reference signal, a position control unit for controlling the motor rotation position, a speed control unit for controlling the motor speed, and a current control unit for controlling the motor current, which are connected in sequence, and a feedback channel including a first feedback unit for feeding back the current rotation position and current rotation speed of the motor, a second feedback unit for feeding back the current current of the motor, and a feedforward unit for selectively compensating the motor current. The position reference unit generates a position reference signal for controlling the motor rotation position according to a set target position, the position control unit outputs a speed reference signal for controlling the motor speed and a position error signal according to the position reference signal from the position reference unit and the position feedback signal from the first feedback unit. The position error signal is used to characterize the position error between the target rotation position and the current rotation position, the speed control unit outputs a first current reference signal according to the speed reference signal from the position control unit and the speed feedback signal from the first feedback unit, the feedforward unit outputs a selectively compensating current signal according to the position error signal from the position control unit, the current control unit outputs a control signal for controlling the motor according to the selectively compensating current signal, the first current reference signal, and the current feedback signal from the second feedback unit; wherein, the feedforward unit includes: a differentiation module for outputting the selectively compensating current signal as zero when the position error signal is greater than a set compensation threshold, and differentiating the position error signal to obtain a differentiation result when the position error signal is not greater than the set compensation threshold. The differentiation result is used as the selectively compensating current signal. The differentiation result is used to characterize the change rate of the position error signal, a compensation coefficient module for correcting the differentiation result from the differentiation module according to a compensation coefficient. The corrected differentiation operation result is used as the selectively compensating current signal. The signal obtained by superimposing the selectively compensating current signal and the first current reference signal is used as a second current reference signal and input to the current control unit.

2. The motor control device according to claim 1, characterized in that, The compensation coefficient is determined according to the load inertia.

3. The motor control device according to claim 1, wherein, The current control unit includes a first proportional integrator. The first proportional integrator performs proportional integration on the difference between the second current reference signal and the current feedback signal and outputs it as the control signal.

4. The motor control device according to claim 3, characterized in that, The corrected differentiation operation result is: the product of the differentiation result and the compensation coefficient; The selectively compensating current positively compensates the first current when the change rate of the position error signal is greater than 0, negatively compensates the first current when the change rate of the position error signal is less than 0, and does not compensate the first current when the change rate of the position error signal is equal to 0.

5. The motor control device according to claim 1, characterized in that, The position error signal is the difference between the position reference signal and the position feedback signal. The position control unit includes a proportional controller. Wherein, the proportional controller processes the position error signal according to a set ratio and outputs it as the rotational speed reference signal.

6. The motor control device according to claim 1, wherein The motor is connected to the driven mechanism through a flexible coupling, or the load inertia of the motor does not match the motor inertia, or the motor has no reduction mechanism. The position reference unit includes a ramp function module and a third filter circuit. After the target position signal is processed by the ramp function module and the third filter circuit in sequence, the position reference signal is output. The target position signal corresponds to the target position of the driven mechanism or the target rotational position of the motor. The compensation threshold is determined according to the position error between the current position and the target position of the driven mechanism.

7. The motor control device according to any one of claims 1 to 6, characterized in that The motor is a brushless DC motor. The selective compensation current signal is a torque current signal for torque current compensation. The current control unit is the current control module in the vector control module for motor field-oriented control. This current control module outputs the first torque reference voltage in the two-phase rotating coordinate system according to the selective compensation current signal, the first current reference signal, and the torque current feedback signal from the second feedback unit; and outputs the first excitation reference voltage in the two-phase rotating coordinate system according to the excitation current feedback signal from the second feedback unit and the given excitation current reference signal. The second feedback unit is the current feedback module in the vector control module. This current feedback module includes a first transformation function. Wherein, The first transformation function performs coordinate transformation on the sampled three-phase current signal according to the angle feedback signal for characterizing the current rotational angle from the first feedback unit, and outputs the torque current feedback signal and the excitation current feedback signal. The vector control module further includes a second transformation function module. The second transformation function module transforms the first torque reference voltage and the first excitation reference voltage from the current control module into the second reference voltage in the two-phase stationary coordinate system according to the angle feedback signal.

8. The motor control device according to claim 7, characterized in that The control unit further includes a pulse width modulation unit. The pulse width modulation unit generates a pulse width modulation wave from the second reference voltage from the second transformation function module. This pulse width modulation wave is used to provide a control signal for the operation of the inverter circuit to the inverter circuit. Wherein, the inverter circuit is used to invert the DC power supply into an AC power supply and supply it to the brushless DC motor. The first feedback unit includes: an encoder for obtaining the rotational position and speed of the motor, a first sampling circuit for obtaining the output signal from the encoder, and a position and speed calculation module for calculating the rotational position and speed of the motor. Wherein, The position and speed calculation module determines the position feedback signal according to the sampling signal for characterizing the current rotational position from the first sampling circuit; determines the speed feedback signal according to the sampling signal and the corresponding time, and determines the angle feedback signal according to the sampling signal.

9. The motor control device according to claim 8, characterized in that, The first feedback unit further includes a first filter circuit, which filters the rotational speed feedback signal from the position and speed calculation module and then outputs it to the rotational speed control unit; The second feedback unit further includes a second sampling circuit for sampling the three-phase current of the DC brushless motor and the DC power supply voltage. The second sampling circuit inputs the sampled current signal into the first transformation function and inputs the sampled DC power supply voltage and the sampled current signal into the fault detection unit; The fault detection unit includes: a second filter circuit and a fault detection module, wherein, the second filter circuit filters the DC power supply voltage signal and the sampled current signal sampled by the second sampling circuit and then inputs them into the fault detection module, and the fault detection module performs motor fault detection according to the input signals; The current control module includes a second proportional-integral controller and a third proportional-integral controller, wherein, the second proportional-integral controller performs proportional integration on the difference between the torque current reference signal and the torque current feedback signal and outputs it as the first torque reference voltage signal, and the third proportional-integral controller performs proportional integration on the difference between the excitation current reference signal and the excitation current feedback signal and outputs it as the first excitation reference voltage signal; The rotational speed control unit includes a fourth proportional-integral controller. Among them, the fourth proportional-integral controller performs proportional integration on the difference between the rotational speed reference signal and the rotational speed feedback signal and outputs it as the first current reference signal.

10. A motor control method, characterized in that, The method includes: obtaining a position feedback quantity for characterizing the current rotational position of the motor, a rotational speed feedback quantity for characterizing the current rotational speed of the motor, and a current feedback quantity for characterizing the current current of the motor, determining a position reference quantity for controlling the rotational position of the motor according to the set target position, determining a rotational speed reference quantity for controlling the rotational speed of the motor according to the position feedback quantity and the position reference quantity, determining a first current reference quantity according to the rotational speed feedback quantity and the rotational speed reference quantity, determining a selective compensation current quantity according to the position error quantity for characterizing the position error between the target rotational position and the current rotational position, determining a control quantity for controlling the motor according to the selective compensation current quantity, the first current reference quantity, and the current feedback quantity, wherein, the determining a selective compensation current quantity according to the position error quantity for characterizing the position error between the target rotational position and the current rotational position includes: when the position error is greater than the set compensation threshold, determining that the selective compensation current quantity is zero; when the position error is not greater than the set compensation threshold, performing differential processing on the position error to obtain the selective compensation current quantity, correcting the selective compensation current quantity according to a compensation coefficient to obtain a corrected selective compensation current quantity.

11. The motor control method according to claim 10, characterized in that, The compensation threshold is determined according to the position error between the current position and the target position of the driven mechanism.

12. The motor control method according to claim 10, wherein The compensation coefficient is determined according to the load inertia.

13. The motor control method according to claim 12, characterized in that, Determining a control quantity for controlling the motor according to the selective compensation current quantity, the first current reference quantity, and the current feedback quantity for characterizing the current current of the motor includes: Superposing the selective compensation current and the first current reference quantity to obtain a second current reference quantity, Subtracting the current feedback quantity from the second current reference quantity to obtain the control quantity.

14. The motor control method according to claim 13, wherein, The correcting the selective compensation current quantity according to a compensation coefficient includes: Taking the product of the selective compensation current quantity and the compensation coefficient as the corrected selective compensation current quantity; The superposing the selective compensation current and the first current reference quantity includes: When the change rate of the position error signal is greater than 0, the selective compensation current positively compensates the first current, When the change rate of the position error signal is less than 0, the selective compensation current negatively compensates the first current, When the change rate of the position error signal is equal to 0, the selective compensation current does not compensate the first current.

15. The motor control method according to claim 14, wherein The motor is a brushless DC motor, The subtracting the current feedback quantity from the second current reference quantity to obtain the control quantity includes: Taking the second current reference quantity as the given value of the torque current and inputting it into a vector control module for controlling the brushless DC motor, Performing vector pulse width modulation on the second voltage reference quantity output by the vector control module to obtain a pulse width modulation wave for controlling an inverter circuit, wherein the inverter circuit is used to invert a DC power supply into an AC power supply for supplying power to the motor.

16. The motor control method according to claim 15, wherein The obtaining a position feedback quantity for characterizing the current rotation position of the motor, a speed feedback quantity for characterizing the current speed of the motor, and a current feedback quantity for characterizing the current current of the motor includes: Determining the position feedback quantity according to the current position information from an encoder, Determining the speed feedback quantity according to the current position information and its corresponding time, Determining an angle feedback quantity for characterizing the current rotation angle according to the current position information and providing it to the vector control module, so that the vector control module determines a torque current feedback quantity for characterizing the current torque current and an excitation current feedback quantity for characterizing the current excitation current according to the sampled AC power supply current; This method further includes: Performing motor fault detection according to the sampled voltage of the DC power supply and the sampled current of the AC power supply.

17. A turnstile system, characterized in that, Including a motor for driving a blocking portion and the motor control device according to any one of claims 1 to 9.

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