Pitch control systems, methods, electronic devices, storage media, and program products

Abstract

This application relates to a pitch control system, method, electronic device, storage medium, and program product. The slave motor control module in this system includes: a voltage loop configured to generate a first speed compensation value for the slave motor based on a feedback value of the slave motor's bus voltage and a given reference value of the slave motor's bus voltage; a speed loop configured to generate a current reference value for the slave motor based on the first speed compensation value, the speed feedback value, and the speed reference value; wherein the speed feedback value and the speed reference value are speed samples from the slave motor at different times; and a current loop configured to control the operation of the slave motor based on the current feedback value and the current reference value. This application, through improvements to the slave motor control module and control method, enables the slave motor to achieve independent control without relying on the communication network within the master and slave motors, while still achieving the cooperative control function of the master and slave motors.

Description

Technical Field

[0001] This application relates to the field of motor control technology, and in particular to pitch control systems, methods, electronic devices, storage media, and program products. Background Technology

[0002] In large wind turbine generators, to enhance the driving force and operational stability of the pitch control system, a design is often adopted in which two or more motors work together to drive the same blade. Currently, the most common coordinated control method is based on a master-slave mode. In this mode, one motor is typically designated as the master motor, directly receiving pitch angle commands from the wind turbine's main controller; the others act as slave motors, tracking the position or speed of the master motor through a real-time communication network, thereby ensuring synchronized movement among the multiple motors.

[0003] The master-slave mode relies on internal communication lines to achieve synchronous and coordinated operation of two or more motors. When this communication link is unexpectedly interrupted, the two or more motor drive units cannot exchange data in real time, losing their ability to work collaboratively and thus unable to output power together. Under the existing control strategy, after the system detects such a fault, it can usually only rely on one drive unit to independently execute an emergency yaw action to ensure the basic safety of the unit. Summary of the Invention

[0004] The purpose of this application is to provide a pitch control system, method, electronic device, storage medium, and program product. By improving the slave motor control module and control method, the slave motor can be independently controlled without relying on the communication network inside the master and slave motors, while still achieving the coordinated control function of the master and slave motors.

[0005] To address the aforementioned technical problems, in a first aspect, embodiments of this application provide a pitch control system. This system includes a slave motor control module, which comprises: a voltage loop configured to generate a first speed compensation value for the slave motor based on a feedback value of the slave motor's bus voltage and a given reference value of the slave motor's bus voltage; a speed loop configured to generate a current reference value for the slave motor based on the first speed compensation value, the speed feedback value, and the speed reference value; wherein the speed feedback value and the speed reference value are speed sampling values ​​of the slave motor at different times; and a current loop configured to control the operation of the slave motor based on the current feedback value and the current reference value.

[0006] Secondly, embodiments of this application provide a pitch control method applied to a pitch control system including a slave motor control module. The method includes: when the slave motor control module operates in a non-interconnection mode, the slave motor control module performs the following steps: generating a first speed compensation amount for the slave motor based on the slave motor bus voltage feedback value and a given slave motor bus voltage reference value; generating a slave motor current reference value based on the first speed compensation amount, the slave motor speed feedback value, and the slave motor speed reference value; wherein the speed feedback value and the speed reference value are speed sampling values ​​of the slave motor at different times; and controlling the operation of the slave motor based on the slave motor current feedback value and the slave motor current reference value.

[0007] Thirdly, embodiments of this application provide an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the above-described method.

[0008] Fourthly, embodiments of this application provide a computer-readable storage medium storing computer instructions, which, when executed by a processor, constitute the method described above.

[0009] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0010] Compared with the prior art, the embodiments described above in this application have at least one or more of the following beneficial effects: In this embodiment, the speed samples of the slave motor at different times are used as the speed reference value and speed feedback value required for the slave motor speed loop calculation. That is, the speed reference value is no longer derived from the speed synchronization command of the master motor, thus eliminating the need for slave motor control to rely on obtaining the speed synchronization command through the master-slave motor communication network. Furthermore, in this embodiment, a voltage loop is added to the slave motor control module. This voltage loop can use the slave motor's bus voltage to calculate the first speed compensation amount of the slave motor. This first speed compensation amount is introduced into the slave motor's speed loop to participate in the control, thereby achieving coordination between the slave and master motors. In other words, this embodiment of the invention, through improvements to the slave motor control module and control method in the pitch control system, enables the slave motor to achieve independent control without relying on the communication network between the master and slave motors, while still achieving the coordinated control function of the master and slave motors. Attached Figure Description

[0011] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0012] Figure 1 This is a schematic diagram of a pitch control system according to an embodiment of this application; Figure 2 yes Figure 1 The detailed diagram of the motor control module structure is provided in the image. Figure 3 This is a schematic diagram of another motor control module provided according to an embodiment of this application; Figure 4 This is a schematic diagram of another pitch control system provided according to an embodiment of this application; Figure 5 This is a schematic diagram of another pitch control system provided according to an embodiment of this application; Figure 6 This is a schematic diagram of a torque backlash elimination module according to an embodiment of this application; Figure 7 yes Figure 6 A detailed diagram of the torque backlash elimination module is shown. Figure 8 This is a schematic diagram of another torque backlash elimination module provided according to an embodiment of this application; Figure 9 yes Figure 8 A detailed diagram of the torque backlash elimination module is shown. Figure 10 This is a flowchart of a pitch control method provided according to an embodiment of this application; Figure 11 This is a flowchart of another pitch control method provided according to an embodiment of this application; and Figure 12 This is a flowchart of another pitch control method provided according to an embodiment of this application. Detailed Implementation

[0013] In existing technologies, the master-slave control method of dual-drive or multi-drive pitch control systems relies on the internal communication network of the master and slave motors. In the event of a communication network failure, emergency pitch return can usually only be performed by a single drive. However, through long-term practice, the inventors of this application have discovered that single-drive emergency pitch return has significant safety hazards and performance limitations. First, the output torque of a single drive is limited, which may lead to insufficient pitch return speed under strong winds or high load conditions, prolonging the time the unit is at risk of overspeed. Second, the sudden concentration of all load on a single drive chain can easily cause mechanical damage such as motor overload and gearbox stress concentration; repeated occurrences over a long period will significantly affect equipment lifespan. Furthermore, single-drive control results in slow system dynamic response and decreased positioning accuracy, potentially causing unstable blade movement and exacerbating unit vibration. Moreover, this effectively eliminates the inherent redundancy and reliability of dual-drive or multi-drive designs; if the only working drive unit also fails during pitch return, it will result in a complete loss of power, exposing the unit to extremely high safety risks. Therefore, the inventors of this application have been exploring a completely new control method that not only maintains the inherent advantages of dual-drive or multi-drive designs but also overcomes the shortcomings of existing master-slave control methods that rely entirely on master-slave communication networks. To this end, the inventors of this application have conducted a detailed study on the meaning and source of the control parameters of each motor in the control of dual-drive or multi-drive pitch systems, as well as the changes in the values ​​of each parameter during the operation of each motor and the relationships between them. Based on this study, the technical solution of this application has been derived.

[0014] To address the aforementioned problems, this application provides a pitch control system, which includes a slave motor control module. The slave motor control module includes: a voltage loop configured to generate a first speed compensation value for the slave motor based on a feedback value of the slave motor's bus voltage and a given reference value of the slave motor's bus voltage; a speed loop configured to generate a current reference value for the slave motor based on the first speed compensation value, the speed feedback value, and the speed reference value; wherein the speed feedback value and the speed reference value are speed samples from the slave motor at different times; and a current loop configured to control the operation of the slave motor based on the current feedback value and the current reference value.

[0015] In this embodiment, the speed samples of the slave motor at different times are used as the speed reference value and speed feedback value required for the slave motor speed loop calculation. That is, the speed reference value is no longer derived from the speed synchronization command of the master motor, thus eliminating the need for slave motor control to rely on obtaining the speed synchronization command through the master-slave motor communication network. Furthermore, a voltage loop is added to the slave motor control module in this embodiment. This voltage loop can use the slave motor's bus voltage to calculate the first speed compensation amount of the slave motor. This first speed compensation amount is introduced into the slave motor's speed loop to participate in the control, thereby achieving coordination between the slave and master motors. The reason why the speed compensation amount calculated using this voltage loop can achieve master-slave coordination is that the inventors discovered in their research that when the master and slave motors are in an ideal coordinated state, the bus voltages of each motor are relatively stable. Here, the bus voltage refers to the DC bus voltage of the motor's driver, which provides the operating voltage for the motor's inverter. Simultaneously, the operating state of the motor's inverter causes fluctuations in the bus voltage. This stable bus voltage can be measured when the motor is operating in an ideal coordinated state or obtained through theoretical calculation. If the slave motor's speed lags behind the master motor's speed, the master motor generates electricity for the slave motor, causing a decrease in the master motor driver's bus voltage and an increase in the slave motor driver's bus voltage. Conversely, if the slave motor's speed exceeds the master motor's speed, the slave motor generates electricity for the master motor, causing a decrease in the slave motor driver's bus voltage and an increase in the master motor driver's bus voltage. Therefore, by using the slave motor's bus voltage under ideal coordination as a benchmark (i.e., the bus voltage reference value), and by measuring the slave motor's bus voltage feedback value in real time, comparing the feedback value with the reference value, master-slave coordination issues can be identified. Furthermore, the first speed compensation amount calculated based on the difference between the feedback and reference values ​​can be used to correct coordination problems between the slave and master motors. Thus, in this embodiment of the invention, improvements to the slave motor control module allow for relatively independent control of the slave motor in the pitch control system, eliminating reliance on the communication network between the master and slave motors, while still enabling coordinated control of both the master and slave motors.

[0016] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details are presented in the various embodiments of the present invention to facilitate a better understanding of this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments. The division of the following embodiments is for ease of description and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined with and referenced by each other without contradiction.

[0017] The pitch control system in this application refers to a dual-drive pitch control system or a multi-drive pitch control system. A dual-drive pitch control system includes one master motor control module and one slave motor control module; a multi-drive pitch control system includes one master motor control module and two or more slave motor control modules. In this application, the main improvement is to the slave motor control module, while the specific structure and control method of the master motor control module are similar to those in the prior art.

[0018] Figure 1 The diagram shown is a schematic diagram of a pitch control system provided in an embodiment of this application. Figure 1 The diagram shows the structure of a slave motor control module, which is also applicable to a multi-drive pitch control system, meaning that the structure of each slave motor control module in the multi-drive pitch control system is the same.

[0019] like Figure 1 In this embodiment, the main motor control module comprises a position loop, a speed loop, and a current loop connected in series. The main motor position loop receives position reference values ​​(total blade angle command) from the host system and position feedback values ​​from the main motor. By adjusting these values, it ensures precise tracking of the main motor shaft end position to the total blade angle command, thereby establishing the reference position and trajectory of the entire pitch system. The speed reference value output by the main motor position loop serves as the given reference value for the main motor speed loop. Based on the speed reference value and the speed feedback value from the main motor, the main motor speed loop outputs a current reference value as the given reference value for the current loop. The main motor current loop, based on the current reference value and the current feedback value from the main motor, controls the main motor through its output. The structure and control method of the main motor control module are largely the same as in existing technologies. It should be noted that the main motor control module in this embodiment can adopt any structure found in existing technologies. Figure 1 This is merely an example and is not limited to this.

[0020] like Figure 1In this circuit, the slave motor control module comprises a voltage loop, a speed loop, and a current loop connected in series. The voltage loop receives the bus voltage feedback value of the slave motor and a given bus voltage reference value, generating a first speed compensation value for the slave motor. The speed loop generates a current reference value for the slave motor based on the first speed compensation value, the speed feedback value, and the speed reference value. The speed feedback value and the speed reference value are speed samples of the slave motor at different times; specifically, the sampling time of the speed reference value is earlier than the sampling time of the speed feedback value. That is, in the control logic of the slave motor, the speed at the previous moment is always used as the target value, and the speed of the slave motor is controlled to align with it. The current loop controls the operation of the slave motor based on the current feedback value and the current reference value. The bus voltage feedback value of the slave motor refers to the DC bus voltage of the slave motor's driver. This DC bus voltage provides the operating voltage for the inverter, and therefore can be detected by a voltage detection device located at the inverter input.

[0021] The position feedback values ​​and speed feedback values ​​of the main motor and the slave motor can be detected by the position and speed sensors installed on the motor; the current feedback values ​​of the main motor and the slave motor can be detected by the current sensors installed at the inverter output terminal of the motor. That is, the current feedback value of the motor can refer to the current value at the inverter output terminal of the motor.

[0022] In this embodiment, the functions of each module in the pitch control system can be implemented on the same physical processor or on different physical processors, and can be designed according to actual needs.

[0023] Figure 2 yes Figure 1 The diagram provided shows a detailed view of the motor control module structure. Figure 2 In this circuit, the voltage loop includes a calculator and a speed-compensated PID controller. The calculator in the voltage loop calculates the voltage difference between the bus voltage reference value and the bus voltage feedback value. The speed-compensated PID controller calculates a first speed compensation amount based on this voltage difference. The speed loop includes a calculator and a speed loop PID controller. The calculator in the speed loop calculates the sum of speeds between the speed reference value and the first speed compensation amount, and calculates the speed difference between this sum of speeds and the speed feedback value. The speed loop PID controller calculates a current reference value based on this speed difference. The current loop includes a calculator and a current loop PID controller. The calculator in the current loop calculates the current difference between the current reference value and the current feedback value. The current loop PID controller calculates the parameter value, such as the voltage value, to be directly applied to the slave motor for control purposes.

[0024] In one example, the reference value of the slave motor's bus voltage can be set as: the slave motor's bus voltage value when the slave motor and master motor are in ideal synchronization. Specifically, the reference value of the slave motor's bus voltage can be set according to the following formula: the slave motor's driver input voltage * sqrt(2) * coefficient. The above formula is set as follows: the driver input voltage refers to the AC input voltage of the slave motor's driver in the ideal master-slave cooperative state; sqrt(2) refers to taking the square root of the driver input voltage; the coefficient is a comprehensive correction factor in engineering practice, which is an engineering experience parameter that integrates "loss compensation", "safety margin" and "control margin". This coefficient is related to the motor's own performance and the power grid environment, and can be obtained by iterating and verifying under multiple constraints. Since this coefficient is related to the motor's own performance, the coefficient corresponding to different motors may be different under the same environment.

[0025] This embodiment provides a novel pitch control system that uses the speed sampled values ​​of the slave motor at different times as the speed reference value and speed feedback value required for the slave motor speed loop calculation. That is, the speed reference value is no longer derived from the speed synchronization command of the master motor, thus eliminating the need for slave motor control to rely on obtaining this speed synchronization command through the master-slave motor communication network. Furthermore, this embodiment adds a voltage loop to the slave motor control module. This voltage loop can use the slave motor's bus voltage to calculate the first speed compensation amount of the slave motor. This first speed compensation amount is introduced into the slave motor's speed loop to participate in the control, thereby achieving coordination between the slave and master motors. In other words, this embodiment improves the slave motor control module in the pitch control system, enabling the slave motor to be controlled independently without relying on the internal communication network between the master and slave motors, while still achieving coordinated control of the master and slave motors. In other words, based on the pitch control system described in this embodiment, the master and slave motors do not need to transmit data through an internal communication network; in fact, the master and slave motors may not even need such a communication network. The slave motor operating in this situation can be referred to as operating in a non-interconnected mode.

[0026] Figure 3 This is a schematic diagram of another slave motor control module provided according to an embodiment of this application. A first controllable path is provided between the bus voltage feedback value receiving end of the voltage loop and the bus voltage detection end of the slave motor. When the first controllable path is in the conducting state, the voltage loop receives the bus voltage feedback value. A second controllable path is provided between the speed reference value receiving end of the speed loop and the speed detection end of the slave motor. When the second controllable path is in the conducting state, the speed loop receives the speed reference value.

[0027] Specifically, a switch S1 is provided between the bus voltage feedback value receiving end of the voltage loop and the bus voltage detection end of the slave motor to form a first controllable path. By controlling the opening or closing of S1, the first controllable path is controlled to be open or closed. When the first controllable path is in the closed state, the voltage loop can receive the bus voltage feedback value. A switch S2 is provided between the speed reference value receiving end of the speed loop and the speed detection end of the slave motor to form a second controllable path. By controlling the opening or closing of S2, the second controllable path is controlled to be open or closed. When the second controllable path is in the closed state, the speed loop can receive the speed reference value.

[0028] The motor control module also includes a mode control unit (not shown). This mode control unit can, when the system starts operating or upon receiving a relevant command, control both the first and second controllable paths to be active, thereby enabling the motor control module to enter that operating state. The mode control unit can also, when the system stops operating or upon receiving a relevant command, control both the first and second controllable paths to be deactivated.

[0029] Figure 4 This is a schematic diagram of another pitch control system provided according to an embodiment of this application. Figure 4 In the system, from the structure of the voltage loop and speed loop of the motor control module, and Figure 3 The parts shown are the same, namely the first controllable pathway and the second controllable pathway, and are the same as those shown. Figure 3 They are the same. The difference lies in... Figure 4 In this system, a switch S3 is installed between the speed reference value receiving terminal of the speed loop of the motor control module and the speed synchronization command output terminal of the main motor control module to form a third controllable path. By controlling the opening or closing of S3, the third controllable path is controlled to be open or closed. When the third controllable path is in the open state, the speed loop can receive the speed synchronization command given by the main motor control module. The speed synchronization command output terminal of the main motor control module is the position loop output terminal in the main motor control module, and the speed reference value output by the position loop is the speed synchronization command.

[0030] Correspondingly, the slave motor can have two operating modes: master-slave mode and no-interconnection mode. In master-slave mode, the slave motor's speed loop receives the speed synchronization command given by the master motor control module and calculates the slave motor's current reference value based on the speed synchronization command and the slave motor's speed feedback value. In no-interconnection mode, the slave motor's voltage loop generates the slave motor's first speed compensation amount based on the slave motor's bus voltage feedback value and the given slave motor bus voltage reference value, and the slave motor's speed loop generates the slave motor's current reference value based on the slave motor's first speed compensation amount, the slave motor's speed feedback value, and the slave motor's speed reference value.

[0031] The mode control unit in the slave motor control module can switch the operating mode of the slave motor control module by opening or closing control switches S1, S2, and S3. Specifically, the mode control unit controls S1 and S2 to open and controls S3 to close, so that the first controllable path is in a non-conductive state, the second controllable path is in a non-conductive state, and the third controllable path is in a conductive state, thereby controlling the slave motor to be in master-slave mode; when it is necessary to switch from master-slave mode to non-interconnection mode, the mode control unit controls S1 and S2 to close and controls S3 to open, so that the first controllable path is in a conductive state, the second controllable path is in a conductive state, and the third controllable path is in a non-conductive state, thereby controlling the slave motor to be in non-interconnection mode.

[0032] In one example, the slave motor can typically operate in master-slave mode. When the mode control unit detects a communication failure between the slave motor control module and the master motor control module, or receives a command from the upper-level controller to switch to non-interconnection mode, it controls the slave motor control module to switch from master-slave mode to non-interconnection mode. Therefore, when a communication failure within the master and slave motors prevents operation in master-slave mode, it can immediately switch to non-interconnection mode without affecting the collaborative control function between the master and slave motors. Furthermore, when the mode control unit detects that the internal communication failure between the master and slave motors has been cleared, or receives a command to switch to master-slave mode, the mode control unit can control the slave motor to switch from non-interconnection mode to master-slave mode.

[0033] Figure 5 This is a schematic diagram of another pitch control system provided according to an embodiment of this application. Figure 5 Examples and Figure 4 The difference in this embodiment is that the system also includes a torque backlash elimination module. This torque backlash elimination module is connected to the master motor, the slave motor, and the slave motor's speed loop. When the slave motor control module operates in master-slave mode, this torque backlash elimination module participates in the control of the slave motor.

[0034] Specifically, when the motor control module operates in master-slave mode, the torque backlash elimination module is configured to: acquire the torque feedback value of the master motor and the torque feedback value of the slave motor; calculate the actual torque difference between the master motor and the slave motor based on the torque feedback values ​​of the master motor and the slave motor; and calculate the second speed compensation amount of the slave motor based on the given reference torque difference, the actual torque difference, and in combination with the PID algorithm.

[0035] Correspondingly, the speed loop of the slave motor control module is configured to generate a current reference value for the slave motor based on the second speed compensation amount of the slave motor, the speed feedback value of the slave motor, and the speed synchronization command given by the master motor control module.

[0036] In this embodiment, the physical quantity of the actual torque difference between the master motor and the slave motor is used to evaluate the impact of mechanical nonlinear factors such as the tooth backlash between the gearbox and the hub. The evaluated impact is then fed back to the control of the slave motor. In other words, the impact of mechanical nonlinear factors is added as a consideration in the control of the slave motor, so that the control of the slave motor can correct this impact as much as possible, thereby improving the actual coordination effect between the slave motor and the master motor during operation.

[0037] refer to Figure 6 and Figure 7 The torque backlash elimination module includes: The torque feedback value acquisition unit 100 is used to acquire the torque feedback value of the main motor and the torque feedback value of the slave motor. The actual torque difference calculation unit 200 is used to calculate the actual torque difference between the main motor and the slave motor based on the torque feedback value of the main motor and the torque feedback value of the slave motor. The speed compensation calculation unit 300 is used to calculate the speed compensation amount of the slave motor based on the given reference torque difference, the actual torque difference, and in conjunction with a PID algorithm; wherein, the speed compensation amount serves as the input to the slave motor control module and participates in the control of the slave motor. Corresponding to Figure 7 In this unit, the speed compensation calculation unit 300 includes a calculator and a slave motor speed compensation PID controller. The calculator calculates the difference between the reference torque difference and the actual torque difference, and the slave motor speed compensation PID controller calculates the speed compensation amount of the slave motor based on the difference.

[0038] In this embodiment, for both the master motor and the slave motor, the torque feedback value acquisition unit 100 can obtain the torque feedback value through the current feedback value. This method is very convenient and has high accuracy.

[0039] The torque feedback value acquisition unit 100 acquires the current feedback value of the main motor and calculates the torque feedback value of the main motor based on the current feedback value. In one example, the current feedback value of the main motor can be decomposed into DQ to obtain the Q-axis current of the main motor, and the torque feedback value of the main motor can be obtained based on the Q-axis current and the torque coefficient of the main motor.

[0040] Similarly, the torque feedback value acquisition unit 100 acquires the current feedback value of the slave motor and calculates the torque feedback value of the slave motor based on the current feedback value. In one example, the current feedback value of the slave motor is decomposed into DQ to obtain the Q-axis current of the slave motor, and the torque feedback value of the slave motor is obtained based on the Q-axis current of the slave motor and the torque coefficient of the slave motor.

[0041] In the above example, both the master motor and the slave motor directly use the Q-axis current as the calculation basis, and the specific calculation method is the same, as follows: The three-phase current feedback value obtained from real-time sampling is subjected to coordinate transformation processing, transforming it from a three-phase stationary coordinate system to a rotating coordinate system that rotates synchronously with the rotor, thereby decomposing it into the corresponding direct-axis current component (D-axis current) and quadrature-axis current component (Q-axis current). Subsequently, the decomposed Q-axis current is multiplied by a pre-calibrated torque coefficient that characterizes the ratio of the electromagnetic torque of the master motor / slave motor to the Q-axis current. After optional filtering processing, the torque feedback value used to characterize the real-time output electromagnetic torque of the master motor / slave motor is obtained. The torque coefficient is determined by the characteristics of the motor itself; different motors, such as the master motor and slave motor, or different slave motors, may have different torque coefficients.

[0042] In this example, the Q-axis current is directly used as the basis for calculation. Essentially, the effective component of the current used to generate electromagnetic torque is extracted, so that the calculated torque feedback value can reflect the instantaneous output torque of the motor most directly and linearly. This avoids coupling errors introduced by factors such as power factor or magnetic field fluctuations, and improves the accuracy of torque feedback and control precision.

[0043] Besides the methods mentioned above, torque feedback values ​​can also be obtained in other ways, as shown in the following examples.

[0044] Direct acquisition via physical sensors: Measured directly by a torque sensor installed in the motor; Estimation method based on power-speed calculation: Given the DC bus voltage, current and system efficiency model of the driver, the input power of the motor can be estimated. At the same time, combined with the motor speed feedback, a rough estimate can be made using the formula torque ≈ power / speed.

[0045] Model estimation based on state observers: By establishing a mathematical model (state-space equation) that includes the motor, load and even the transmission chain, and taking easily measurable physical quantities (such as motor speed and current) as input, the system uses algorithms such as Romberg observers and Kalman filters to "observe" or "estimate" the state variables that cannot be directly measured or are too costly to measure in real time, namely torque.

[0046] In this embodiment, the reference torque difference can be the torque difference under ideal conditions. Under ideal conditions, the master motor and the slave motor are perfectly coordinated, so the torque difference under ideal conditions should be zero. However, in actual operation, there may still be some completely tolerable differences. Therefore, the reference torque difference can be set to an allowable error range, such as 0~10 N / m. That is, as long as the actual torque difference is within this error range, it is considered that the master motor and the slave motor have achieved the expected ideal coordination.

[0047] The speed compensation calculation unit 300 calculates the actual torque difference based on the real-time acquired torque feedback values ​​of the master motor and slave motor. Subsequently, this actual torque difference is compared with a reference torque difference, and the resulting deviation is used as an input signal to a PID (Proportional-Integral-Derivative) controller for adjustment. This PID controller responds and corrects to the dynamic changes in torque deviation in real time according to preset proportional, integral, and derivative coefficients, ultimately outputting a speed compensation amount. This speed compensation amount is used as input to the slave motor control module and superimposed on the slave motor's synchronous speed reference (speed reference). By dynamically fine-tuning its speed, the output torque is changed, thereby driving the actual torque difference to approach the reference torque difference, achieving precise torque following and balance among multiple motors.

[0048] Figure 8 and Figure 9 This is another torque backlash elimination module provided in this application embodiment. The torque backlash elimination module may further include a speed limiting unit 400, or the torque backlash elimination module may simultaneously include a speed limiting unit 400 and a position difference determination unit 500 to limit the speed compensation amount. It should be noted that... Figure 8 and Figure 9 The illustration shows an example where both the speed limiting unit 400 and the position difference determination unit 500 exist simultaneously; however, it is also possible to include only the speed limiting unit 400. Specific details are as follows.

[0049] Method 1: Limiting based solely on speed limiting unit 400; that is, this speed limiting unit is used to limit the speed compensation amount to obtain the limited speed compensation amount; wherein, the limited speed compensation amount is used as the input of the slave motor control module to participate in the control of the slave motor.

[0050] Specifically, a speed compensation limiting range is set, and the speed limiting unit 400 limits the speed compensation amount according to the preset speed compensation limiting range to obtain the limited speed compensation amount. The speed compensation limiting range includes an upper limit value and a lower limit value. When the speed compensation amount calculated in step 203 exceeds the speed compensation limiting range, it will be clamped to the upper or lower limit value of the speed compensation limiting range, so the limited speed compensation amount is the upper or lower limit value of the speed compensation limiting range; when the speed compensation amount calculated in step 203 does not exceed the speed compensation limiting range, the limited speed compensation amount is the speed compensation amount calculated in step 203.

[0051] The speed compensation amount is generated from the deviation between the actual torque difference and the reference torque difference. This deviation can be positive or negative, depending on whether the instantaneous torque of the slave motor is too high or too low. If the slave motor torque is too high, the control algorithm will calculate a negative speed compensation amount to reduce its torque, which is then added to the slave motor's speed reference value, representing a deceleration command to make it "output less power." If the slave motor torque is too low, a positive speed compensation amount will be calculated to increase its torque, which is then added to the slave motor's speed reference value, representing an acceleration command to make it "output more power." Correspondingly, the lower limit of the speed compensation limit range can be set to a negative value, and the upper limit can be set to a positive value; however, this is not the only possibility, and the setting method of the lower and upper limits can be determined according to actual needs.

[0052] In this method, by setting a speed compensation limit range to limit the speed compensation amount calculated based on torque, it is possible to avoid sudden changes in speed compensation amount caused by torque sudden changes due to occasional factors or torque measurement errors, thereby ensuring system stability and preventing position loss between master and slave motors due to excessive or unreasonable speed compensation.

[0053] Method 2: The speed limiting unit 400 and the position difference judgment unit 500 coexist. That is, the position difference judgment unit 500 calculates the position difference between the master motor and the slave motor based on the position feedback values ​​of the master motor and the slave motor; when the position difference is greater than or equal to the position difference threshold, the speed limiting unit 400 uses the preset maximum allowable speed compensation amount as the speed compensation amount; when the position difference is less than the position difference threshold, it limits the speed compensation amount according to the preset speed compensation limiting range to obtain the limited speed compensation amount.

[0054] In this method, position deviation is introduced and considered as a priority factor, combined with the amplitude limiting processing in Method 1. Specifically, the position difference between the position feedback values ​​of the master motor and the slave motor is calculated in real time, and the relationship between this position difference and the position difference threshold is determined. When the position difference reaches or exceeds the position difference threshold, it indicates that the actual position difference between the master motor and the slave motor is approaching the safety boundary. At this time, the speed compensation amount is forcibly set to the maximum allowable speed compensation amount. When the position difference is less than the position difference threshold, the amplitude limiting processing in Method 1 is adopted. The maximum allowable speed compensation amount can be positive or negative. When the slave motor position is ahead of the master motor position, the speed compensation amount is forcibly set to the negative maximum allowable speed compensation amount and superimposed on the slave motor speed reference value to represent a deceleration command. When the slave motor position is behind the master motor position, the speed compensation amount is forcibly set to the positive maximum allowable speed compensation amount and superimposed on the slave motor speed reference value to represent an acceleration command.

[0055] The position difference threshold can be set according to actual needs. A common principle is that when the position difference between the master motor and the slave motor reaches this threshold, the resulting mechanical wear and its impact on the lifespan of the motor and gearbox mechanical structure are considered to be very significant. Therefore, it is necessary to correct the slave motor's speed as soon as possible to improve the coordination between the slave and master motors and reduce mechanical wear. For example, this position difference threshold can be set to the backlash width of the large gear ring in the impeller hub. That is, the pinions on the output shafts of multiple pitch drive motors (one master motor and one or more slave motors) mesh with the large gear ring mounted on the impeller hub to drive the entire impeller. The pinions on the output shafts of the multiple pitch drive motors work together to drive the large gear ring on the impeller hub to rotate. When the position difference between the slave motor and the master motor reaches the backlash width of the large gear ring in the impeller hub, it is considered that there is a significant coordination problem between the slave and master motors, which needs to be corrected as soon as possible.

[0056] In this method two, the maximum permissible speed compensation for positive and negative values ​​can be equal to or different from the upper and lower limits of the speed compensation limit range in method one; these can be set according to actual conditions and needs.

[0057] In this method, the position difference between the master motor and the slave motor is obtained and used as the priority judgment factor. When the position difference between the two is too large, the slave motor is corrected with the maximum allowable speed compensation. Considering that the essence of the collaboration between the master motor and the slave motor is position collaboration, using the position difference as the direct judgment factor can quickly detect extremely poor collaboration. When this happens, the positions of the slave motor and the master motor are immediately pulled back to the allowable error range as quickly as possible, thereby shortening the duration of the extreme situation as much as possible and minimizing the wear and damage to the mechanical structure.

[0058] This application also relates to a pitch control method, corresponding to the above-mentioned... Figure 1 , Figure 2 The pitch control system shown in the embodiment includes the slave motor control module therein. For example... Figure 10 The flowchart shown is of the pitch control method. When the slave motor control module is operating in non-interconnection mode, the method includes the following steps.

[0059] Step 101: The motor control module generates the first speed compensation amount of the slave motor based on the feedback value of the slave motor's bus voltage and the given reference value of the slave motor's bus voltage.

[0060] Step 102: The motor control module generates a current reference value for the slave motor based on the first speed compensation amount of the slave motor, the speed feedback value of the slave motor, and the speed reference value of the slave motor; wherein, the speed feedback value and the speed reference value are speed sampling values ​​of the slave motor at different times.

[0061] Step 103: The motor control module controls the operation of the slave motor based on the current feedback value and the current reference value of the slave motor.

[0062] The reference value of the bus voltage of the slave motor can be set as: the bus voltage value of the slave motor when the slave motor and the master motor in the system are in ideal synchronization.

[0063] Furthermore, corresponding to Figure 3 The slave motor control module shown in the embodiment performs the following steps to enter the above-mentioned interconnection-free mode: The path between the bus voltage feedback value receiving terminal of the motor control module and the bus voltage detection terminal of the motor is opened to obtain the bus voltage feedback value. The speed reference value is obtained by connecting the speed reference value receiving end of the motor control module to the speed detection end of the motor.

[0064] Furthermore, corresponding to Figure 4 The method further includes, when the slave motor control module shown in the embodiment switches from master-slave mode to the above-mentioned non-interconnection mode: The path between the speed reference value receiving terminal of the motor control module and the speed synchronization command output terminal of the main motor control module in the system is disconnected.

[0065] Furthermore, when the motor control module detects a communication failure with the main motor control module, or when it receives a command to switch to the non-interconnection mode, it switches from the master-slave mode to the aforementioned non-interconnection mode.

[0066] Furthermore, corresponding to Figure 5The pitch control system including a torque backlash elimination module shown in the embodiments of this application also provides another pitch control method, see reference. Figure 11 The flowchart is shown. When the motor control module is operating in master-slave mode, the method also includes the following steps.

[0067] Step 201: The torque backlash elimination module obtains the torque feedback value of the main motor and the torque feedback value of the slave motor. Step 202: The torque backlash elimination module calculates the actual torque difference between the main motor and the slave motor based on the torque feedback values ​​of the main motor and the slave motor. Step 203: The torque backlash elimination module calculates the second speed compensation amount from the motor based on the given reference torque difference, the actual torque difference, and in conjunction with the PID algorithm. Step 204: The slave motor control module generates a current reference value for the slave motor based on the second speed compensation amount of the slave motor, the speed feedback value of the slave motor, and the speed synchronization command given by the master motor control module. Step 205: The motor control module controls the operation of the slave motor based on the current feedback value and the current reference value of the slave motor.

[0068] Furthermore, corresponding to Figures 6-7 , Figures 8-9 The torque backlash elimination module shown in the embodiment further includes step 203a between steps 203 and 204. (See reference...) Figure 12 The flowchart shown.

[0069] Step 203a: The torque backlash elimination module performs amplitude limiting processing on the second speed compensation amount to obtain the limited second speed compensation amount.

[0070] The steps described above are for clarity only. In practice, they can be combined into one step or some steps can be broken down into multiple steps. As long as they include the same logical relationship, they are all within the scope of protection of this patent. Adding insignificant modifications or introducing insignificant designs to the algorithm or process, but without changing the core design of the algorithm and process, are also within the scope of protection of this patent.

[0071] It is not difficult to see that the above method embodiments correspond to the above system embodiments, and the above method embodiments can be implemented in conjunction with the above system embodiments. The relevant technical details mentioned in the above system embodiments remain effective in the above method embodiments, and will not be repeated here to avoid repetition. Correspondingly, the relevant technical details mentioned in the above method embodiments can also be applied to the above system embodiments, and the above method embodiments and the above system embodiments have the same beneficial effects.

[0072] Furthermore, the examples mentioned in the above embodiments can be freely combined, and any combination can be understood as an embodiment. The terms "embodiment" or "example" appearing in various locations in the specification do not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Those skilled in the art will understand that the embodiments described herein can be combined with other embodiments.

[0073] Embodiments of the present invention relate to an electronic device, including at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the method embodiments described above.

[0074] The memory and processor are connected via a bus, which can include any number of interconnecting buses and bridges, connecting various circuits of one or more processors and memories. The bus can also connect various other circuits, such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and will not be described further herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be a single element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices over a transmission medium. Data processed by the processor is transmitted over the wireless medium via an antenna, which further receives data and transmits it to the processor.

[0075] The processor manages the bus and general processing, and also provides various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory is used to store data used by the processor during operation.

[0076] In addition, embodiments of this application relate to a computer-readable storage medium storing computer instructions that, when executed by a processor, implement the above-described method embodiments.

[0077] In addition, embodiments of this application relate to a computer program product, including a computer program that, when executed by a processor, implements the above-described method embodiments.

[0078] That is, those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a device (which may be a microcontroller, chip, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0079] Those skilled in the art will understand that the above embodiments are specific embodiments for implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention.

Claims

1. A pitch control system, characterized in that, The system includes a slave motor control module, and the slave motor control module includes: A voltage loop is configured to generate a first speed compensation amount for the slave motor based on the bus voltage feedback value of the slave motor and a given bus voltage reference value of the slave motor. A speed loop is configured to generate a current reference value for the slave motor based on a first speed compensation amount, a speed feedback value, and a speed reference value; wherein the speed feedback value and the speed reference value are speed sampling values ​​of the slave motor at different times. A current loop is configured to control the operation of the slave motor based on the current feedback value of the slave motor and the current reference value of the slave motor.

2. The system according to claim 1, characterized in that, A first controllable path is provided between the bus voltage feedback value receiving terminal of the voltage loop and the bus voltage detection terminal of the slave motor. When the first controllable path is in the conducting state, the voltage loop receives the bus voltage feedback value. A second controllable path is provided between the speed reference value receiving end of the speed loop and the speed detection end of the slave motor. When the second controllable path is in the conducting state, the speed loop receives the speed reference value. The slave motor control module further includes a mode control unit, which is configured to: control the first controllable path to be in a conducting state and control the second controllable path to be in a conducting state.

3. The system according to claim 2, characterized in that, A third controllable path is provided between the speed reference value receiving end of the speed loop and the speed synchronization command output end of the main motor control module in the system. When the third controllable path is in the conducting state, the speed loop receives the speed synchronization command given by the main motor control module. The mode control unit is also configured to: The first controllable path is controlled to be in a conducting state, the second controllable path is controlled to be in a conducting state, and the third controllable path is controlled to be in a non-conducting state, so that the slave motor control module enters a non-interconnection mode; or... The first controllable path is controlled to be in a non-conducting state, the second controllable path is controlled to be in a non-conducting state, and the third controllable path is controlled to be in a conducting state, so that the slave motor control module enters the master-slave mode.

4. The system according to claim 3, characterized in that, The mode control unit is also configured to: When a communication failure is detected between the slave motor control module and the master motor control module, or when a command to switch to the non-interconnection mode is received, the slave motor control module is controlled to enter the non-interconnection mode.

5. The system according to claim 1, characterized in that, The reference value for the bus voltage of the slave motor is set to the bus voltage value of the slave motor when the slave motor and the master motor in the system are in ideal synchronization.

6. The system according to any one of claims 1 to 5, characterized in that, The system also includes a torque backlash elimination module; when the slave motor control module operates in master-slave mode... The torque backlash elimination module is configured as follows: Obtain the torque feedback value of the main motor and the torque feedback value of the slave motor; The actual torque difference between the main motor and the slave motor is calculated based on the torque feedback value of the main motor and the torque feedback value of the slave motor. The second speed compensation amount of the slave motor is calculated based on the given reference torque difference, the actual torque difference, and in conjunction with the PID algorithm. The speed loop of the slave motor control module is configured to generate a current reference value for the slave motor based on the second speed compensation amount of the slave motor, the speed feedback value of the slave motor, and the speed synchronization command given by the master motor control module.

7. The system according to claim 6, characterized in that, The torque backlash elimination module is further configured to: after calculating the second speed compensation amount, limit the second speed compensation amount to obtain the limited second speed compensation amount.

8. A pitch control method, characterized in that, A method applied to a pitch control system including a slave motor control module, the method comprising: when the slave motor control module operates in a non-interconnection mode... The slave motor control module generates a first speed compensation amount for the slave motor based on the feedback value of the slave motor's bus voltage and the given reference value of the slave motor's bus voltage. The slave motor control module generates a current reference value for the slave motor based on the first speed compensation amount of the slave motor, the speed feedback value of the slave motor, and the speed reference value of the slave motor; wherein, the speed feedback value and the speed reference value are speed sampling values ​​of the slave motor at different times. The slave motor control module controls the operation of the slave motor based on the current feedback value and the current reference value of the slave motor.

9. The method according to claim 8, characterized in that, The slave motor control module performs the following steps to enter the non-interconnection mode: The path between the bus voltage feedback value receiving terminal and the bus voltage detection terminal of the slave motor is opened to obtain the bus voltage feedback value; The path between the speed reference value receiving end and the speed detection end of the slave motor is opened to obtain the speed reference value.

10. The method according to claim 9, characterized in that, When the slave motor control module switches from master-slave mode to the non-interconnection mode, the slave motor control module also performs the following steps: The path between the speed reference value receiving terminal and the speed synchronization command output terminal of the main motor control module in the system is disconnected.

11. The method according to claim 10, characterized in that, The method further includes: When the slave motor control module detects a communication failure with the master motor control module, or when it receives a command to switch to the non-interconnection mode, it switches from the master-slave mode to the non-interconnection mode.

12. The method according to claim 8, characterized in that, The reference value for the bus voltage of the slave motor is set to the bus voltage value of the slave motor when the slave motor and the master motor in the system are in ideal synchronization.

13. The method according to any one of claims 8 to 12, characterized in that, The system further includes a torque backlash elimination module; the method further includes: when the slave motor control module operates in master-slave mode... The torque backlash elimination module acquires the torque feedback value of the main motor and the torque feedback value of the slave motor; The torque backlash elimination module calculates the actual torque difference between the main motor and the slave motor based on the torque feedback value of the main motor and the torque feedback value of the slave motor. The torque backlash elimination module calculates the second speed compensation amount of the slave motor based on the given reference torque difference, the actual torque difference, and in conjunction with a PID algorithm. The slave motor control module generates the current reference value of the slave motor based on the second speed compensation amount of the slave motor, the speed feedback value of the slave motor, and the speed synchronization command given by the master motor control module. The slave motor control module controls the operation of the slave motor based on the current feedback value and the current reference value of the slave motor.

14. The method according to claim 13, characterized in that, After the torque backlash elimination module calculates the second speed compensation amount of the slave motor based on the given reference torque difference, the actual torque difference, and in conjunction with the PID algorithm, and before the slave motor control module generates the current reference value of the slave motor based on the second speed compensation amount of the slave motor, the speed feedback value of the slave motor, and the speed synchronization command given by the master motor control module, the following steps are also included: The torque backlash elimination module performs amplitude limiting processing on the second speed compensation amount to obtain the limited second speed compensation amount.

15. An electronic device, characterized in that, include: At least one processor; as well as, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method as described in any one of claims 8 to 14.

16. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a processor, implement the method of any one of claims 8 to 14.

17. A computer program product, characterized in that, Includes a computer program that, when executed by a processor, implements the method of any one of claims 8 to 14.

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