A control method, device and system for a rotary guide actuator

Abstract

The present disclosure provides a control method, device and system for a rotary steering actuator, which is applied to a rotary steering actuator with a brushless DC motor and an output mechanism, wherein the control method includes: obtaining a three-phase voltage signal and a three-phase current signal of the brushless DC motor; obtaining a commutation moment of the brushless DC motor based on the three-phase voltage signal; obtaining a starting current signal and a speed signal of the brushless DC motor based on the three-phase current signal and the three-phase voltage signal; obtaining a current reference parameter of the brushless DC motor based on a target output value of the output mechanism; and controlling the output operation of the brushless DC motor drive output mechanism based on the commutation moment of the brushless DC motor, the starting current signal of the brushless DC motor, the speed signal of the brushless DC motor, and the current reference parameter. The present disclosure can determine the rotor position of the brushless DC motor without a Hall sensor, thereby realizing the sensorless control of the rotary steering actuator.

Description

Technical Field

[0001] The present disclosure relates to the field of rotary steerable actuators, and in particular to a control method, device and system for a rotary steerable actuator. Background Art

[0002] The rotary steerable actuator is the core part of the oil drilling system. The existing rotary steerable actuator generally includes a pressure sensor and a DC brushless motor with a Hall sensor. When working, the Hall sensor obtains the rotor position information of the DC brushless motor, so that the control system can drive the DC brushless motor to operate, and then drive the output mechanism to move and output a certain pressure.

[0003] Since the working environment of the oil drilling system is characterized by high temperature and strong vibration, the Hall sensor has poor resistance to high temperature and vibration. It is very easy to fail in this working environment, and the sensing signal is easily interfered, resulting in the DC brushless motor not being able to work properly, reducing the reliability of the rotary guide actuator. Summary of the invention

[0004] In order to solve the above technical problems, the present disclosure provides a control method, device and system for a rotary steering actuator, which can determine the rotor position of a brushless DC motor without a Hall sensor, thereby realizing sensorless control of the rotary steering actuator.

[0005] The technical solution of the present disclosure is achieved as follows:

[0006] In a first aspect, the present disclosure provides a control method for a rotary steering actuator, using a rotary steering actuator having a brushless DC motor and an output mechanism, wherein the brushless DC motor is drivingly connected to the output mechanism, and the method comprises:

[0007] Acquiring three-phase voltage signals and three-phase current signals of the brushless DC motor;

[0008] Based on the three-phase voltage signal, obtaining the commutation timing of the brushless DC motor;

[0009] Based on the three-phase current signal and the three-phase voltage signal, obtaining a starting current signal and a speed signal of the brushless DC motor;

[0010] Based on the target output value of the output mechanism, obtaining a current reference parameter of the brushless DC motor;

[0011] Based on the commutation timing of the brushless DC motor, the starting current signal of the brushless DC motor, the speed signal of the brushless DC motor, and the current reference parameter, the brushless DC motor is controlled to drive the output mechanism to output operation.

[0012] In one implementation, before obtaining the commutation time of the brushless DC motor based on the three-phase voltage signal, the control method further includes:

[0013] Controlling any two phases of the brushless DC motor to be energized so that the rotor of the brushless DC motor rotates to a position consistent with the stator magnetic field of the brushless DC motor;

[0014] Controlling the brushless DC motor to commutate according to a six-step commutation method, and gradually increasing a commutation frequency and a phase voltage of the brushless DC motor until a rotation speed of the brushless DC motor reaches a preset rotation speed value;

[0015] Acquiring the commutation time of the brushless DC motor based on the three-phase voltage signal, comprising:

[0016] When the speed of the brushless DC motor reaches a preset speed value, the back electromotive force of the brushless DC motor is obtained based on the three-phase voltage signal at that moment;

[0017] Based on the back electromotive force of the DC brushless motor, obtaining a zero-crossing point of the DC brushless motor;

[0018] Based on the zero-crossing point, a commutation timing of the brushless DC motor is determined.

[0019] In one embodiment, the target output value of the output mechanism includes any one of a speed target value and an output pressure target value;

[0020] When the target output value of the output mechanism includes a speed target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism; comprising:

[0021] Based on the speed target value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation;

[0022] When the target output value of the output mechanism includes an output pressure target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism; comprising:

[0023] Based on the output pressure target value and the current output pressure of the output mechanism, a speed reference value of the brushless DC motor is obtained through PI operation;

[0024] Based on the speed reference value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation.

[0025] In one embodiment, after controlling the brushless DC motor to drive the output mechanism to perform an output operation, the control method further includes:

[0026] Based on the operating power parameter of the brushless DC motor, the output pressure of the output mechanism is obtained.

[0027] In one embodiment, obtaining the output pressure of the output mechanism based on the operating power parameter of the brushless DC motor includes:

[0028] When the output pressure of the output mechanism gradually increases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation:

[0029] F=a1*p' 2 +b1*p'+c1;

[0030] When the output pressure of the output mechanism gradually decreases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation:

[0031] F=a2*p' 2 +b2*p'+c2;

[0032] Wherein, F is the output pressure of the output mechanism; P' is the operating power parameter of the brushless DC motor; a1, a2, b1, b2, c1, c2 are all calibration parameters of the output mechanism.

[0033] In a second aspect, the present disclosure provides a control device for a rotary steering actuator, which uses a rotary steering actuator having a DC brushless motor and an output mechanism, wherein the DC brushless motor is drivingly connected to the output mechanism, and the device comprises:

[0034] A current and voltage acquisition module, used to acquire three-phase voltage signals and three-phase current signals of the brushless DC motor;

[0035] A commutation timing acquisition module, used to acquire the commutation timing of the brushless DC motor based on the three-phase voltage signal;

[0036] A starting current acquisition module, used for acquiring a starting current signal and a speed signal of the brushless DC motor based on the three-phase current signal and the three-phase voltage signal;

[0037] A current reference parameter acquisition module, used to acquire a current reference parameter of the brushless DC motor based on a target output value of the output mechanism;

[0038] The execution control module controls the DC brushless motor to drive the output mechanism to perform an output operation based on the commutation timing of the DC brushless motor, the starting current signal of the DC brushless motor, the speed signal of the DC brushless motor, and the current reference parameter.

[0039] In one embodiment, the control device of the rotary steering actuator further includes:

[0040] A rotor positioning module, used for controlling the energization of any two phases of the brushless DC motor, so that the rotor of the brushless DC motor rotates to a position consistent with the stator magnetic field of the brushless DC motor;

[0041] A motor acceleration module, used for controlling the DC brushless motor to commutate according to a six-step commutation method, and gradually increasing a commutation frequency and a phase voltage of the DC brushless motor until a rotation speed of the DC brushless motor reaches a preset rotation speed value;

[0042] The switching time acquisition module comprises:

[0043] A back electromotive force acquisition module, configured to acquire the back electromotive force of the brushless DC motor based on the three-phase voltage signal at the time when the speed of the brushless DC motor reaches a preset speed value;

[0044] A zero-crossing point acquisition module, used for acquiring the zero-crossing point of the brushless DC motor based on the back electromotive force of the brushless DC motor;

[0045] A commutation timing confirmation module is used to determine the commutation timing of the brushless DC motor based on the zero crossing point.

[0046] In one embodiment, the target output value of the output mechanism includes any one of a speed target value and an output pressure target value;

[0047] When the target output value of the output mechanism includes a speed target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism; comprising:

[0048] Based on the speed target value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation;

[0049] When the target output value of the output mechanism includes an output pressure target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism; comprising:

[0050] Based on the output pressure target value and the current output pressure of the output mechanism, a speed reference value of the brushless DC motor is obtained through PI operation;

[0051] Based on the speed reference value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation.

[0052] In one embodiment, the control device of the rotary steering actuator further includes:

[0053] An output pressure acquisition module, used for acquiring the output pressure of the output mechanism based on the operating power parameter of the brushless DC motor;

[0054] The output pressure acquisition module is specifically used for:

[0055] When the output pressure of the output mechanism gradually increases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation:

[0056] F=a1*p' 2 +b1*p'+c1;

[0057] When the output pressure of the output mechanism gradually decreases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation:

[0058] F=a2*p' 2 +b2*p'+c2;

[0059] Wherein, F is the output pressure of the output mechanism; P' is the operating power parameter of the brushless DC motor; a1, a2, b1, b2, c1, c2 are all calibration parameters of the output mechanism.

[0060] In a third aspect, the present disclosure provides a control system for a rotary steering actuator, comprising:

[0061] The controller is used to execute the above control method.

[0062] The advantages or beneficial effects of the above technical solution include at least:

[0063] The control method disclosed in the present invention obtains the three-phase voltage signal and the three-phase current signal of the brushless DC motor; and based on the three-phase voltage signal, obtains the commutation moment of the brushless DC motor, thereby obtaining the position information of the rotor, and can obtain the position information of the rotor without using a position sensing device such as a Hall sensor, thereby realizing the sensorless control of the brushless DC motor and improving the control stability of the brushless DC motor. At the same time, the control method disclosed in the present invention obtains the starting current signal of the brushless DC motor based on the three-phase current signal, and obtains the current reference parameter of the brushless DC motor based on the target output value of the output mechanism; thereby, the precise control of the rotary guide actuator can be realized according to the starting current signal and the current reference parameter. Since the control method disclosed in the present invention can obtain the position information of the rotor without a position sensing device such as a Hall sensor, it can solve the shortcomings of the existing control method of the rotary guide actuator, such as high failure rate and poor stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The accompanying drawings illustrate exemplary embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0065] Figure 1 A schematic flow chart of a control method according to an exemplary embodiment of the present disclosure is shown;

[0066] Figure 2 A schematic diagram of a process for obtaining the commutation timing of a brushless DC motor according to an exemplary embodiment of the present disclosure is shown;

[0067] Figure 3 A schematic diagram of a pre-start process according to an exemplary embodiment of the present disclosure is shown;

[0068] Figure 4 A schematic diagram of a process for obtaining a current reference parameter of a brushless DC motor when a target output value of an output mechanism includes a speed target value according to an exemplary embodiment of the present disclosure is shown;

[0069] Figure 5 A schematic diagram of a process for obtaining a current reference parameter of a brushless DC motor when the target output value of the output mechanism includes an output pressure target value according to an exemplary embodiment of the present disclosure is shown;

[0070] Figure 6 A schematic diagram of a process for obtaining the output pressure of an output mechanism according to an exemplary embodiment of the present disclosure is shown;

[0071] Figure 7 A schematic diagram showing a flow chart of obtaining an output pressure estimation algorithm of an output mechanism according to an exemplary embodiment of the present disclosure is shown;

[0072] Figure 8 A schematic diagram showing the logic principle of a control method in a pressure control mode according to an exemplary embodiment of the present disclosure is shown;

[0073] Fig. 9 A schematic structural diagram of a control device according to an exemplary embodiment of the present disclosure is shown;

[0074] Fig.10 A schematic diagram showing a structure when a control device according to an exemplary embodiment of the present disclosure includes a rotor positioning module, a motor acceleration module and an output pressure acquisition module;

[0075] Fig.11 A schematic structural diagram of a commutation timing acquisition module according to an exemplary embodiment of the present disclosure is shown;

[0076] Fig.12A logical schematic diagram of a control system according to an exemplary embodiment of the present disclosure is shown;

[0077] Fig.13 A circuit schematic diagram of a control system according to an exemplary embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0078] Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are only for exemplary purposes and are not intended to limit the scope of protection of the present disclosure.

[0079] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in the present disclosure may be combined with each other. The present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0080] It should be understood that the various steps described in the method embodiments of the present disclosure may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present disclosure is not limited in this respect.

[0081] The terms "including", "having" and their variations used herein are open inclusions, i.e., "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description.

[0082] Reference Figure 1 An embodiment of the present disclosure provides a control method for a rotary steering actuator, which uses a rotary steering actuator having a DC brushless motor and an output mechanism, wherein the DC brushless motor is drivingly connected to the output mechanism.

[0083] Since the brushless DC motor needs to continuously commutate the stator current to make the rotor rotate, the speed control of the brushless DC motor requires knowing the specific rotor position information. Generally, Hall sensors are used to detect the rotor pole position. However, Hall sensors have disadvantages such as slow response, large temperature drift, and poor anti-interference ability, which affect the control stability and control accuracy of the brushless DC motor.

[0084] In view of the above problems, the present invention discloses a control method for a rotary steering actuator, referring to Figure 1 , control methods include:

[0085] Step S100, obtaining three-phase voltage signals and three-phase current signals of the brushless DC motor;

[0086] Step S200, obtaining the commutation timing of the brushless DC motor based on the three-phase voltage signal;

[0087] Step S300, obtaining a starting current signal and a speed signal of the brushless DC motor based on the three-phase current signal and the three-phase voltage signal;

[0088] Step S400, obtaining a current reference parameter of the brushless DC motor based on a target output value of the output mechanism;

[0089] Step S500, based on the commutation time of the brushless DC motor, the starting current signal of the brushless DC motor, the speed signal of the brushless DC motor and the current reference parameter of the brushless DC motor, the output operation of the brushless DC motor drive output mechanism is controlled. Specifically, the rotor position of the brushless DC motor can be determined by the commutation time, and the operation of the brushless DC motor can be controlled by using the speed signal as a feedback signal combined with the starting current signal and the current reference parameter.

[0090] The control method disclosed in the present invention obtains the three-phase voltage signal and the three-phase current signal of the brushless DC motor; and based on the three-phase voltage signal, obtains the commutation moment of the brushless DC motor, thereby obtaining the position information of the rotor, and can obtain the position information of the rotor without using a position sensing device such as a Hall sensor, thereby realizing the sensorless control of the brushless DC motor and improving the control stability of the brushless DC motor. At the same time, the control method disclosed in the present invention obtains the starting current signal of the brushless DC motor based on the three-phase current signal, and obtains the current reference parameter of the brushless DC motor based on the target output value of the output mechanism; thereby, the precise control of the rotary guide actuator can be realized according to the starting current signal and the current reference parameter. Since the control method disclosed in the present invention can obtain the position information of the rotor without a position sensing device such as a Hall sensor, it can solve the shortcomings of the existing control method of the rotary guide actuator, such as high failure rate and poor stability.

[0091] Reference Figure 1 and Figure 2 In step S200, the commutation time of the brushless DC motor is obtained through the three-phase voltage signal of the brushless DC motor, which specifically includes:

[0092] Step S201, detecting the back electromotive force of the brushless DC motor and obtaining the zero-crossing point of the brushless DC motor;

[0093] Step S202, determining the commutation time of the brushless DC motor according to the zero-crossing point.

[0094] Since the DC brushless motor has a low speed when it is started and the back electromotive force cannot be detected, the present disclosure pre-starts the DC brushless motor before step S200;

[0095] Reference Figure 3 , the pre-startup specifically includes the following steps:

[0096] S601, controlling any two phases of the brushless DC motor to be energized so that the rotor of the brushless DC motor rotates to a position consistent with the stator magnetic field of the brushless DC motor;

[0097] S602, control the brushless DC motor to commutate in sequence according to the six-step commutation method, and gradually increase the commutation frequency and the phase voltage of the brushless DC motor until the speed of the brushless DC motor reaches a preset speed value. In this embodiment, the brushless DC motor is a three-phase brushless DC motor, and the six-step commutation method enables each two phases of the brushless DC motor to be energized in sequence, realizing sequential commutation, thereby causing the brushless DC motor to rotate.

[0098] After the brushless DC motor is started, when the speed of the brushless DC motor reaches a preset speed value, the back electromotive force of the brushless DC motor is obtained based on the three-phase voltage signals at that moment, and then the commutation moment of the brushless DC motor is determined.

[0099] As a preferred embodiment, the rotary steering actuator of this example includes at least a speed control mode and a pressure control mode; in the speed control mode, the rotary steering actuator is operated at a set speed, and the output pressure of the rotary steering actuator is open-loop controlled; in the pressure control mode, the rotary steering actuator is output according to the set pressure. Therefore, in step S400, when the rotary steering mechanism adopts the speed control mode, the target output value of the output mechanism includes the speed target value; when the rotary steering mechanism adopts the pressure control mode, the target value of the output mechanism includes the output pressure target value.

[0100] In the pressure control mode, step S300 further includes acquiring torque information of the brushless DC motor based on the three-phase current signal and the three-phase voltage signal;

[0101] Step S500, based on the commutation moment of the brushless DC motor, the starting current signal of the brushless DC motor, the speed signal of the brushless DC motor, the torque information and the current reference parameter of the brushless DC motor, the output operation of the brushless DC motor driving output mechanism is controlled. Specifically, the rotor position of the brushless DC motor can be determined by the commutation moment, the operating power parameter of the brushless DC motor can be calculated by the speed signal and the torque information, and the pressure value of the output mechanism can be estimated by the operating power parameter, so that the estimated output pressure value is used as a feedback signal, combined with the starting current signal and the current reference parameter, to control the operation of the brushless DC motor.

[0102] Reference Figure 4 When the target output value of the output mechanism includes a speed target value, step S400 includes:

[0103] Step S401, based on the speed target value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation; at this time, the speed of the output mechanism is closed-loop controlled, and the output pressure of the output mechanism is open-loop controlled;

[0104] Reference Figure 5 When the target output value of the output mechanism includes the target output pressure value, step S400 includes:

[0105] Step S402, based on the output pressure target value and the current output pressure of the output mechanism, a speed reference value of the brushless DC motor is obtained through PI calculation;

[0106] Step S403, based on the speed reference value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation.

[0107] In the pressure control module mode, the pressure loop is used as the outermost loop of the DC brushless motor control, that is, the output pressure of the output mechanism and the output result of the PI operation of the current output pressure are used as the speed reference value of the speed loop, and finally the rotary guide actuator is controlled to output according to the set output pressure target value.

[0108] Reference Figure 6 As a preferred implementation of this example, after step S500, the method further includes:

[0109] Step S700, based on the operating power parameter of the brushless DC motor, obtain the output pressure of the output mechanism. Specifically, step S700 includes:

[0110] Step S701, when the output pressure of the output mechanism gradually increases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy equation (1):

[0111] F=a1*p' 2 +b1*p'+c1; (1)

[0112] Step S702: When the output pressure of the output mechanism gradually decreases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy equation (2):

[0113] F=a2*p' 2 +b2*p'+c2; (2)

[0114] Wherein, F is the output pressure of the output mechanism; p' is the operating power parameter of the brushless DC motor; a1, a2, b1, b2, c1, c2 are all calibration parameters of the output mechanism.

[0115] Reference Figure 7 , Figure 7 The schematic diagram of the acquisition process of the output pressure estimation algorithm of the output mechanism is shown; that is, the acquisition method of the above equation (1), equation (2) and calibration parameters a1, a2, b1, b2, c1, c2, this embodiment can be obtained by experiment, specifically including the following steps:

[0116] Step 801, control the brushless DC motor to drive the output mechanism to operate, in speed mode, start from the preset minimum speed, after the operation is stable, record the current value of the brushless DC motor operating power parameter p' and the value of the output pressure F of the output mechanism, and then increase the speed by a set increment each time, and record the value of the brushless DC motor operating power parameter p' and the value of the output pressure F of the output mechanism after each increment until the maximum output pressure is reached; in this step, preferably, the preset minimum speed is 200rpm, and the set increment is 100rpm;

[0117] Step 802, using a tool such as Matlab, with the operating power parameter p' of the brushless DC motor as the horizontal coordinate and the output pressure F of the output mechanism as the vertical coordinate, a quadratic polynomial is fitted to obtain a functional relationship between the output pressure of the output mechanism and the operating power parameter of the brushless DC motor when the output pressure of the output mechanism gradually increases, i.e., equation (1);

[0118] Step 803, control the brushless DC motor to drive the output mechanism to operate, starting from the maximum output pressure of the output mechanism, and after the operation is stable, record the current value of the brushless DC motor operating power parameter p' and the value of the output pressure F of the output mechanism, and then decrease according to the set decrement, and record the value of the brushless DC motor operating power parameter p' and the value of the output pressure F of the output mechanism after each submission until it is reduced to the minimum speed; in this step, the preferred minimum speed is 200rpm, and the set decrement is 100rpm;

[0119] Step 804, using tools such as Matlab, with the DC brushless motor operating power parameter p' as the horizontal coordinate and the output pressure F of the output mechanism as the vertical coordinate, a quadratic polynomial is used to perform the sum, and the functional relationship between the output pressure of the output mechanism and the operating power parameter of the DC brushless motor is obtained when the output pressure of the output mechanism gradually decreases, i.e., equation (2).

[0120] The coefficients a1, a2, b1, b2, c1, and c2 obtained through experiments are used as calibration parameters of the output mechanism, and the calibration parameters are real numbers.

[0121] The control method of the rotary steerable actuator of the embodiment of the present disclosure can estimate the output pressure of the output mechanism in real time based on equations (1) and (2) during the process of controlling the operation of the rotary steerable actuator. Therefore, there is no need to use a pressure sensor. This not only reduces the hardware cost of the control system, but also avoids the problems of low sensing accuracy and unstable operation of the pressure sensor in complex environments.

[0122] In this embodiment, the operating power parameter of the brushless DC motor is positively correlated with the output pressure value of the output mechanism. The brushless DC motor feeds back the speed n and torque T information during operation. According to the motor drag principle, the instantaneous power p of the brushless DC motor is T×n / 9550. Without considering the coefficient, the instantaneous power of the brushless DC motor is low-pass filtered to obtain the operating power parameter p'=LPF(T×n) of the brushless DC motor.

[0123] Figure 8 The schematic diagram of the logic principle of the control method of the embodiment of the present disclosure in the pressure control mode is shown; in this embodiment, steps S100 to S300 are the sensorless control algorithm of the brushless DC motor, and the three-phase phase voltage V of the brushless DC motor is obtained through the ADC conversion module. a 、V b and V c , and the three-phase current I a ,I b and I c Based on the three-phase voltage and three-phase current, the torque T, angular velocity ω and starting current signal I of the brushless DC motor can be obtained according to the sensorless control algorithm. q , the speed n of the brushless DC motor is obtained through the angular velocity ω, the instantaneous power of the brushless DC motor is calculated according to the motor drag principle through the speed n and the torque T, and then the operating power parameter p' of the brushless DC motor is obtained, the output pressure F of the output mechanism is calculated through the operating power parameter p' combined with equation (1) or equation (2), the output pressure and the output pressure target value (given value) are used as input parameters of the pressure loop, PI operation is performed, and the operation result is used as the given value of the speed loop, the PI operation of the speed loop is performed in combination with the angular velocity ω, and the operation result is used as the given value of the current loop, and the starting current signal I q The PI operation of the current loop is performed, and the operation result is used to produce the corresponding SVPWM signal (Space Vector Pulse Width Modulation, SWPWM, space vector pulse width modulation). After three-phase inversion according to the SVPWM signal, the operation of the brushless DC motor is controlled.

[0124] As can be seen from the above, the control method of the embodiment of the present disclosure only needs to collect three-phase voltage signals and current signals to determine the zero-crossing point of the phase voltage and determine the commutation time of the DC brushless motor, thereby realizing the sensorless control of the DC brushless motor. At the same time, during the operation of the DC brushless motor, by calculating the three-phase current signals, the torque information of the DC brushless motor can be calculated in real time. The speed information can also be calculated in real time according to the commutation frequency of the three-phase current, the size of the three-phase voltage and other parameters, so that the operating power parameter p' of the DC brushless motor can be calculated in real time, and then the output pressure F of the output mechanism can be obtained according to equation (1) or equation (2), so as to realize the precise control of the rotary guide actuator. Through experimental calculation, in the pressure control mode, the accuracy of the output pressure can be within 5%.

[0125] Reference Fig. 9 The embodiment of the present disclosure also provides a control device for a rotary steering actuator, which uses a rotary steering actuator having a DC brushless motor and an output mechanism, wherein the DC brushless motor is drivingly connected to the output mechanism, and the device comprises:

[0126] The current and voltage acquisition module 100 is used to acquire the three-phase voltage signal and the three-phase current signal of the brushless DC motor;

[0127] A commutation timing acquisition module 200 is used to acquire the commutation timing of the brushless DC motor based on the three-phase voltage signal;

[0128] The starting current acquisition module 300 is used to acquire the starting current signal of the brushless DC motor based on the three-phase current signal;

[0129] A current reference parameter acquisition module 400 is used to acquire a current reference parameter of the brushless DC motor based on a target output value of the output mechanism;

[0130] The execution control module 500 is used to control the output operation of the brushless DC motor drive output mechanism based on the commutation timing of the brushless DC motor, the starting current signal of the brushless DC motor and the current reference parameter of the brushless DC motor.

[0131] Reference Fig.10 In one embodiment, the control device of the rotary steering actuator further comprises:

[0132] The rotor positioning module 600 is used to control the energization of any two phases of the brushless DC motor so that the rotor of the brushless DC motor rotates to a position consistent with the stator magnetic field of the brushless DC motor;

[0133] The motor acceleration module 700 is used to control the brushless DC motor to commutate in sequence according to the six-step commutation method, and gradually increase the commutation frequency and the phase voltage of the brushless DC motor until the speed of the brushless DC motor reaches a preset speed value;

[0134] Reference Fig.11 , the switching time acquisition module 200 includes:

[0135] The back electromotive force acquisition module 201 is used to acquire the back electromotive force of the brushless DC motor based on the three-phase voltage signal at the moment when the speed of the brushless DC motor reaches a preset speed value;

[0136] A zero-crossing point acquisition module 202 is used to acquire the zero-crossing point of the brushless DC motor based on the back electromotive force of the brushless DC motor;

[0137] The commutation time confirmation module 203 is used to determine the commutation time of the brushless DC motor based on the zero crossing point.

[0138] In one embodiment, the target output value of the output mechanism includes any one of a speed target value and an output pressure target value;

[0139] When the target output value of the output mechanism includes a speed target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism; including:

[0140] Based on the speed target value and the current speed value of the brushless DC motor, the current reference parameter of the brushless DC motor is obtained through PI calculation;

[0141] When the target output value of the output mechanism includes the target output pressure value, obtaining the current reference parameter of the brushless DC motor based on the target output value of the output mechanism; including:

[0142] Based on the output pressure target value and the current output pressure of the output mechanism, a speed reference value of the brushless DC motor is obtained through PI calculation;

[0143] Based on the speed reference value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation.

[0144] Reference Fig.10 In one embodiment, the control device of the rotary steering actuator further comprises:

[0145] The output pressure acquisition module 800 is used to acquire the output pressure of the output mechanism based on the operating power parameter of the brushless DC motor;

[0146] The output pressure acquisition module 800 is specifically used for:

[0147] When the output pressure of the output mechanism gradually increases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation:

[0148] F=a1*p' 2+b1*p'+c1;

[0149] When the output pressure of the output mechanism gradually decreases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation:

[0150] F=a2*p' 2 +b2*p'+c2;

[0151] Wherein, F is the output pressure of the output mechanism; P' is the operating power parameter of the brushless DC motor; a1, a2, b1, b2, c1, and c2 are all calibration parameters of the output mechanism.

[0152] All relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module, and will not be repeated here.

[0153] In a third aspect, the embodiments of the present disclosure further provide a control system for a rotary steering actuator, referring to Fig.12 and Fig.13 , the control system includes:

[0154] The controller 10 is used to execute the above method; the controller can adopt a DSP control chip, preferably TMS320F28069F, which can output six PWM signals and has multiple ADC conversion interfaces, and can be used to collect voltage signals and current signals.

[0155] The control system further comprises:

[0156] The motor drive module 20 is connected to the controller 10 and is used to drive the DC brushless motor of the rotary guide actuator. The motor drive module includes a three-phase inverter.

[0157] The secondary power supply circuit 30 includes a buck regulator, which is used to convert the power supply into the working power supply of the circuit modules such as the DSP control chip and the motor drive module; the buck regulator can be a high temperature resistant buck regulator of model TPS62100-HT;

[0158] The bus voltage acquisition circuit 40, the input end of the bus voltage acquisition circuit 40 is connected to the secondary power supply circuit 30, and the output end is connected to the controller 10, including a resistor R3 and a resistor R4. After the bus voltage is divided by the resistor R3 and the resistor R4, it is input to the conversion interface ADC6 of the DSP control chip; the bus voltage is the output voltage of the secondary power supply circuit;

[0159] A three-phase voltage acquisition circuit 50, wherein the input end of the three-phase voltage acquisition circuit 50 is connected to the three-phase voltage of the brushless DC motor, and the output end is connected to the ADC conversion interface of the controller 10, and is used to acquire the three-phase voltage signal of the brushless DC motor. The three-phase voltage acquisition circuit includes three voltage-dividing resistors. Each phase voltage of the brushless DC motor is respectively divided by a voltage-dividing resistor and then respectively input to the conversion interface ADC3, the conversion interface ADC4 and the conversion interface ADC5 of the DSP control chip;

[0160] The three-phase current acquisition circuit 60 has an input end connected to the motor drive module, and an output end connected to the ADC conversion interface of the controller 10, and is used to collect the three-phase circuit signal of the DC brushless motor. The three-phase current acquisition circuit includes a sampling resistor R1, a sampling resistor R2, an operational amplifier U1 and an operational amplifier U2. The sampling resistor R1 and the sampling resistor R2 collect any two-phase current from the motor drive module, and after being amplified by the operational amplifier U1 and the operational amplifier respectively, they are input to the conversion interface ADC1 and the conversion interface ADC2 of the DSP control chip.

[0161] The communication circuit 70 is connected to the controller and is used to communicate with the host computer, receive control instructions from the host computer, and feed back the working information of the controller.

[0162] The control system of this embodiment collects three-phase voltage signals and current signals, uses a controller to execute the above control method, determines the zero-crossing point of the phase voltage, and determines the commutation moment of the DC brushless motor, thereby realizing sensorless control of the DC brushless motor. At the same time, during the operation of the DC brushless motor, the torque information of the DC brushless motor can be calculated in real time by calculating the three-phase current signals. The speed information can also be calculated in real time based on parameters such as the commutation frequency of the three-phase current and the size of the three-phase voltage. Therefore, the operating power parameters of the DC brushless motor can be calculated in real time, and then the output pressure of the output mechanism can be obtained, thereby realizing precise control of the rotary guide actuator.

[0163] Those skilled in the art should understand that the above embodiments are only for the purpose of clearly illustrating the present disclosure, and are not intended to limit the scope of the present disclosure. For those skilled in the art, other changes or modifications may be made based on the above disclosure, and these changes or modifications are still within the scope of the present disclosure.

Claims

1. A control method for a rotary guide actuator, characterized in that: A rotary guide actuator having a brushless DC motor and an output mechanism is used, wherein the brushless DC motor is drivingly connected to the output mechanism, and the control method includes: Acquiring three-phase voltage signals and three-phase current signals of the brushless DC motor; Based on the three-phase voltage signal, obtaining the commutation timing of the brushless DC motor; Based on the three-phase current signal and the three-phase voltage signal, obtaining a starting current signal and a speed signal of the brushless DC motor; Based on the target output value of the output mechanism, obtaining a current reference parameter of the brushless DC motor; Based on the commutation timing of the brushless DC motor, the starting current signal of the brushless DC motor, the speed signal of the brushless DC motor, and the current reference parameter, control the brushless DC motor to drive the output mechanism to output operation; After controlling the brushless DC motor to drive the output mechanism to perform output operation, the control method further includes: acquiring the output pressure of the output mechanism based on the operating power parameter of the brushless DC motor; Based on the operating power parameter of the brushless DC motor, the output pressure of the output mechanism is obtained, including: when the output pressure of the output mechanism gradually increases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation: F=a1*p' 2 +b1*p'+c1; When the output pressure of the output mechanism gradually decreases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation: F=a2*p’ 2 +b2*p’+c2; Wherein, F is the output pressure of the output mechanism; p' is the operating power parameter of the brushless DC motor; a1, a2, b1, b2, c1, c2 are all calibration parameters of the output mechanism.

2. The control method of the rotary steering actuator according to claim 1, characterized in that: Before obtaining the commutation time of the brushless DC motor based on the three-phase voltage signal, the control method further includes: Controlling any two phases of the brushless DC motor to be energized so that the rotor of the brushless DC motor rotates to a position consistent with the stator magnetic field of the brushless DC motor; Controlling the brushless DC motor to commutate according to a six-step commutation method, and gradually increasing a commutation frequency and a phase voltage of the brushless DC motor until a rotation speed of the brushless DC motor reaches a preset rotation speed value; Acquiring the commutation time of the brushless DC motor based on the three-phase voltage signal, comprising: When the speed of the brushless DC motor reaches a preset speed value, the back electromotive force of the brushless DC motor is obtained based on the three-phase voltage signal at that moment; Based on the back electromotive force of the DC brushless motor, obtaining a zero-crossing point of the DC brushless motor; Based on the zero-crossing point, a commutation timing of the brushless DC motor is determined.

3. The control method of the rotary steering actuator according to claim 1, characterized in that: The target output value of the output mechanism includes any one of a speed target value and an output pressure target value; When the target output value of the output mechanism includes a speed target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism includes: obtaining the current reference parameter of the brushless DC motor through PI operation based on the speed target value and the current speed value of the brushless DC motor; When the target output value of the output mechanism includes an output pressure target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism includes: Based on the output pressure target value and the current output pressure of the output mechanism, a speed reference value of the brushless DC motor is obtained through PI operation; Based on the speed reference value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation.

4. A control device for a rotary guide actuator, characterized in that: A rotary guide actuator having a brushless DC motor and an output mechanism is used, wherein the brushless DC motor is drivingly connected to the output mechanism, and the device comprises: A current and voltage acquisition module, used to acquire three-phase voltage signals and three-phase current signals of the brushless DC motor; A commutation timing acquisition module, used to acquire the commutation timing of the brushless DC motor based on the three-phase voltage signal; A starting current acquisition module, used for acquiring a starting current signal and a speed signal of the brushless DC motor based on the three-phase current signal and the three-phase voltage signal; A current reference parameter acquisition module, used to acquire a current reference parameter of the brushless DC motor based on a target output value of the output mechanism; An execution control module controls the brushless DC motor to drive the output mechanism to perform an output operation based on the commutation timing of the brushless DC motor, the starting current signal of the brushless DC motor, the speed signal of the brushless DC motor, and the current reference parameter; It also includes: an output pressure acquisition module, which is used to acquire the output pressure of the output mechanism based on the operating power parameter of the brushless DC motor; The output pressure acquisition module is specifically used for: When the output pressure of the output mechanism gradually increases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation: F=a1*p' 2 +b1*p'+c1; When the output pressure of the output mechanism gradually decreases, the output pressure of the output mechanism and the operating power parameter of the brushless DC motor satisfy the following equation: F=a2*p’ 2 +b2*p’+c2; Wherein, F is the output pressure of the output mechanism; p' is the operating power parameter of the brushless DC motor; a1, a2, b1, b2, c1, c2 are all calibration parameters of the output mechanism.

5. The control device for the rotary guide actuator according to claim 4, characterized in that: Also includes: A rotor positioning module, used for controlling the energization of any two phases of the brushless DC motor, so that the rotor of the brushless DC motor rotates to a position consistent with the stator magnetic field of the brushless DC motor; A motor acceleration module, used for controlling the DC brushless motor to commutate according to a six-step commutation method, and gradually increasing a commutation frequency and a phase voltage of the DC brushless motor until a rotation speed of the DC brushless motor reaches a preset rotation speed value; The switching time acquisition module comprises: A back electromotive force acquisition module, configured to acquire the back electromotive force of the brushless DC motor based on the three-phase voltage signal at the time when the speed of the brushless DC motor reaches a preset speed value; A zero-crossing point acquisition module, used for acquiring the zero-crossing point of the brushless DC motor based on the back electromotive force of the brushless DC motor; A commutation timing confirmation module is used to determine the commutation timing of the brushless DC motor based on the zero crossing point.

6. The control device for the rotary guide actuator according to claim 4, characterized in that: The target output value of the output mechanism includes any one of a speed target value and an output pressure target value; When the target output value of the output mechanism includes a speed target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism; comprising: Based on the speed target value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation; When the target output value of the output mechanism includes an output pressure target value, obtaining a current reference parameter of the brushless DC motor based on the target output value of the output mechanism; comprising: Based on the output pressure target value and the current output pressure of the output mechanism, a speed reference value of the brushless DC motor is obtained through PI operation; Based on the speed reference value and the current speed value of the brushless DC motor, a current reference parameter of the brushless DC motor is obtained through PI operation.

7. A control system for a rotary steering actuator, characterized in that: include: A controller for executing the control method of the rotary steering actuator as described in any one of claims 1 to 3.

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