Satellite-borne servo antenna control system based on heterogeneous FPGA and control method thereof

Abstract

The application relates to a satellite-borne servo antenna control system based on a heterogeneous FPGA and a control method thereof, and belongs to the technical field of satellite-borne servo antenna control. The system comprises a heterogeneous FPGA, an S-shaped curve planner, a position type PID controller, a micro-step subdivision controller, a double-H-bridge driving chip, a stepping motor, a double-channel rotary transformer and a rotary transformer decoding chip; the heterogeneous FPGA comprises a PS end and a PL end. The system constructs a software and hardware collaborative control architecture based on the heterogeneous FPGA, places complex trajectory planning and PID calculation control algorithms in the PS end to improve development flexibility and maintainability, and places high real-time micro-step subdivision control in the PL end to ensure control certainty. On this basis, through feedforward-feedback compound closed-loop control formed by the PS end and the PL end, the smoothness of an antenna operation trajectory and high tracking precision are ensured, and jitter in the stepping motor control process is optimized.

Description

Technical Field

[0001] This application relates to the field of spaceborne servo antenna control technology, and in particular to a spaceborne servo antenna control system and control method based on heterogeneous FPGA. Background Technology

[0002] With the accelerating pace of global informatization, the demand for high-throughput and high-reliability satellite communication services continues to grow, placing higher demands on the performance of spaceborne communication payloads. As a key component of spaceborne communication systems, the performance of the pointing mechanism of the spaceborne servo antenna directly determines the establishment, maintenance, and transmission efficiency of the communication link. Among these, the pointing accuracy of the antenna pointing mechanism is a core performance indicator for evaluating its ability to execute high-precision ground-pointing commands and achieve complex space scanning modes, and this pointing accuracy ultimately depends on the control performance of its control system. Therefore, developing a spaceborne servo antenna control system with extremely high control accuracy is a fundamental prerequisite for achieving high-precision and high-stability pointing of the spaceborne servo antenna.

[0003] However, the development of current spaceborne servo antenna control systems still faces several severe challenges:

[0004] First, traditional control schemes based on general-purpose processors employ sequential execution, and interrupts and task scheduling introduce unpredictable delays, making it difficult to meet the stringent real-time and deterministic requirements of high-precision control. Second, while integrating all functions (such as trajectory planning and communication protocols) into a single FPGA (Field-Programmable Gate Array) can improve determinism, it suffers from high development difficulty, high resource consumption, and poor flexibility, making subsequent algorithm updates and on-board maintenance extremely difficult. Finally, the conventional PID (Proportional-Integral-Derivative) direct-drive stepper motor method suffers from high vibration and noise, and low-speed crawling problems, resulting in an uneven antenna trajectory and limiting the improvement of final control accuracy.

[0005] In summary, existing technologies have significant shortcomings in terms of real-time control, flexibility, and smoothness of operational trajectory, and there is an urgent need for an innovative high-precision control architecture to meet the high-standard control requirements of modern spaceborne servo antennas. Summary of the Invention

[0006] Therefore, it is necessary to provide a spaceborne servo antenna control system and its control method based on heterogeneous FPGA to address the above-mentioned technical problems.

[0007] A spaceborne servo antenna control system based on heterogeneous FPGA, the system comprising: a heterogeneous FPGA, an S-curve planner, a position-type PID controller, a microstepping controller, a dual H-bridge driver chip, a stepper motor, a dual-channel rotary transformer, and a rotary transformer decoding chip; the heterogeneous FPGA includes a PS terminal and a PL terminal; the stepper motor is a two-phase type;

[0008] The PS terminal is used to control the S-curve planner and the position PID controller to perform motor trajectory planning and motor stepping speed calculation respectively, based on the target angle command received from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back from the PL terminal, and output the target speed and rotation direction of the stepper motor to the PL terminal.

[0009] The PL terminal is used to control the microstepping controller to perform microstepping control of the motor step size according to the received target speed and rotation direction, and output four PWM pulse signals to the dual H-bridge driver chip. After the dual H-bridge driver chip drives the stepper motor's control antenna pointing mechanism to rotate towards the target angle, and after the dual-channel resolver and resolver decoding chip detect and output the actual position of the stepper motor, the PL terminal is also used to periodically collect the coarse and fine machine code values ​​representing the actual position of the stepper motor output by the resolver decoding chip, and feed them back to the PS terminal to realize closed-loop control of the antenna pointing mechanism's rotation angle.

[0010] Furthermore, after receiving the target angle command from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back from the PL terminal at the PS terminal, and converting the target angle command into the target position of the stepper motor, the S-curve planner is used to periodically calculate the planned position based on the target position and the actual position of the stepper motor, and outputs the planned position at the current moment to the position-type PID controller; the position-type PID controller is used to perform differential calculation between the planned position and the actual position of the stepper motor at the current moment to obtain the position error, and outputs the target speed and rotation direction of the stepper motor to the PL terminal by performing PID calculation on the position error.

[0011] Furthermore, the microstepping controller includes a speed control module, a microstepping lookup table module, and a microstepping control module;

[0012] The speed control module is used to control the speed mode of the stepper motor based on the target speed and rotation direction output by the PS terminal;

[0013] The microstep lookup module is used to look up the microstep number corresponding to the target speed and rotation direction in the microstep table;

[0014] The microstepping control module is connected to the speed control module and the microstepping lookup table module respectively. It is used to calculate the electrical angle based on the output of the speed control module and the microstepping sequence number output by the microstepping lookup table module, calculate the optimized current based on the electrical angle, and finally generate four PWM pulse signals based on the optimized current and output them to the dual H-bridge driver chip.

[0015] Furthermore, the four PWM pulse signals are divided into two groups, each group including both positive and negative PWM pulse signals. The PWM pulse signal values ​​are calculated as follows:

[0016] Based on the given number of microsteps, the 360° electrical angle is divided into equal parts to obtain the electrical angle value of each microstep. Based on the electrical angle corresponding to the microstep number output by the microstep lookup module, the corresponding optimized current is generated. The value range of the optimized current is -1.0 to 1.0.

[0017] Determine the sign of the optimized current. When the current is greater than 0, configure the positive phase PWM pulse signal value in each group as the product of the optimized current and MAX_DUTY, and configure the negative phase PWM pulse signal value in each group as 0; otherwise, configure the positive phase PWM pulse signal value in each group as 0, and configure the negative phase PWM pulse signal value in each group as the product of the negative value of the optimized current and MAX_DUTY; where MAX_DUTY is the preset maximum duty cycle parameter of PWM.

[0018] Furthermore, the microstepping controller also includes a register set, which includes write registers and read registers;

[0019] The write registers include a mode switching register, a PWM frequency register, a pulse increment register, a rotation direction register, a rotation speed register, and a configuration output register. These registers are used to receive external control commands and configure the motor drive's control / operating mode, PWM output frequency, number of motor rotation pulses, motor rotation direction, motor rotation speed, and output port functions. The read registers include a remaining increment register and a resolver position value register. These registers are used to provide feedback to the outside world on the real-time operating status of the motor drive, including reading the remaining rotation pulses and the actual position data of the motor.

[0020] Furthermore, the dual-channel rotary transformer is used to detect the actual position of the stepper motor; the rotary transformer decoding chip is connected to the dual-channel rotary transformer and is used to receive the output signal of the dual-channel rotary transformer for decoding, and output coarse and fine machine code values ​​representing the actual position of the stepper motor.

[0021] Furthermore, after receiving the coarse and fine machine code values ​​representing the actual position of the stepper motor periodically fed back from the PL end, the PS end is also used for combined error correction of the resolver coarse and fine machine code.

[0022] The error correction principle of the resolver roughing and finishing machine combination is as follows:

[0023] The last 12 bits of the coarse machine code value are shifted and compared with the fine machine code value to determine whether the coarse machine code value is ahead or behind the fine machine code value. Then, the first four bits of the coarse machine code value are compensated or shifted back to obtain the first four bits of the corrected coarse machine code value. These four bits are then combined with the 16 bits of the fine machine code value to form a 20-bit resolution angle value, thus completing the error correction.

[0024] Furthermore, the PS and PL terminals communicate via the FIC bus.

[0025] A method for controlling a spaceborne servo antenna based on a heterogeneous FPGA, the method being implemented based on the aforementioned spaceborne servo antenna control system based on a heterogeneous FPGA, includes the following steps:

[0026] At the PS end, based on the target angle command received from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back from the PL end, the S-curve planner and the position PID controller are controlled to perform motor trajectory planning and motor stepping speed calculation respectively, and the target speed and rotation direction of the stepper motor are output to the PL end.

[0027] At the PL end, the microstepping controller is controlled to perform microstepping control of the motor step size according to the received target speed and rotation direction, and four PWM pulse signals are output to the dual H-bridge driver chip.

[0028] The control antenna pointing mechanism of the stepper motor is rotated to the target angle by the dual H-bridge driver chip. After the dual-channel rotary transformer and the resolver decoding chip detect and output the actual position of the stepper motor, the coarse and fine machine code values ​​representing the actual position of the stepper motor are periodically collected by the PL terminal and fed back to the PS terminal to realize the closed-loop control of the rotation angle of the antenna pointing mechanism.

[0029] The aforementioned spaceborne servo antenna control system and its control method based on heterogeneous FPGA have the following advantages compared to existing technologies:

[0030] 1. This application utilizes a heterogeneous FPGA-based hardware-software separation mechanism for control function partitioning. Under this architecture, highly complex control algorithms (such as S-curve trajectory planning and position-based PID calculation) are deployed on the PS (Power Supply) terminal, leveraging its software advantages to simplify development and facilitate subsequent algorithm upgrades and on-board maintenance. High real-time control tasks (such as microstepping control and pulse generation) are fixed on the PL (Power Producer) terminal, ensuring precise timing and extremely high determinism in motor control. This control function partitioning fundamentally solves the problems of high development difficulty and poor flexibility caused by integrating all functions into hardware logic in a single FPGA solution, achieving "decoupling of hardware and software updates" and significantly improving system maintainability.

[0031] 2. This application is based on a deep hardware and software collaboration mechanism of heterogeneous FPGA. From the PS end to the PL end, the stepper motor control planning is carried out by curve trajectory planning, PID calculation and microstepping control. From the PL end to the PS end, the feedback adjustment of motor control is carried out by periodically collecting the actual position of the motor. The feedforward-feedback composite closed-loop control is realized in a comprehensive manner, which together ensures the smoothness of the antenna running trajectory and high tracking accuracy, and optimizes the jitter in the stepper motor control process. Attached Figure Description

[0032] Figure 1This is a schematic diagram of the structure of a spaceborne servo antenna control system based on a heterogeneous FPGA in one embodiment;

[0033] Figure 2 This is a functional collaboration diagram of a spaceborne servo antenna control system based on a heterogeneous FPGA in one embodiment.

[0034] Figure 3 This is a schematic diagram of the error correction principle of the rotary transformer coarsening and finishing machine combination in one embodiment. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0036] In one embodiment, such as Figure 1 and 2 As shown, a spaceborne servo antenna control system based on heterogeneous FPGA is provided, including: heterogeneous FPGA, S-curve planner, position PID controller, microstepping controller, dual H-bridge driver chip, stepper motor, dual-channel rotary transformer and rotary decoder chip; the heterogeneous FPGA includes PS (Processing System) terminal and PL (Programmable Logic) terminal, and the stepper motor is two-phase.

[0037] The PS end is the processing system, and the PL end is the programmable logic. Specifically, the PS end has functions such as system initialization, multi-axis collaborative scheduling, complex trajectory planning, and parameter management and distribution; the PL end has functions such as speed mode control, fine-grained control, and data acquisition.

[0038] The PS terminal is used to control the S-curve planner and the position-type PID controller to perform motor trajectory planning and motor stepping speed calculation respectively, based on the target angle command received from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back from the PL terminal, and outputs the target speed and rotation direction of the stepper motor to the PL terminal.

[0039] The PL terminal is used to control the microstepping controller to perform microstepping control of the motor step size based on the received target speed and rotation direction, and outputs four PWM (Pulse Width Modulation) pulse signals to the dual H-bridge driver chip. After the dual H-bridge driver chip drives the stepper motor's control antenna pointing mechanism to rotate towards the target angle, and after the dual-channel resolver and resolver decoding chip detect and output the actual position of the stepper motor, the PL terminal is also used to periodically acquire the coarse and fine machine code values ​​representing the actual position of the stepper motor output by the resolver decoding chip, and feed them back to the PS terminal to achieve closed-loop control of the antenna pointing mechanism's rotation angle. Specifically, as shown... Figure 2 As shown, the dual H-bridge driver chip is used to output drive current according to four PWM pulse signals, and drive the stepper motor to control the antenna pointing mechanism to rotate towards the target angle according to the drive current.

[0040] The aforementioned spaceborne servo antenna control system based on heterogeneous FPGA constructs a hardware-software co-control architecture based on heterogeneous FPGA. It places complex trajectory planning and PID calculation control algorithms at the PS (Power Position) terminal to improve development flexibility and maintainability, while placing high real-time microstepping control at the PL (Power Probe) terminal to ensure control determinism. This effectively overcomes the drawbacks of high resource consumption and difficult upgrades associated with single FPGA solutions. Furthermore, the feedforward-feedback composite closed-loop control formed by the PS and PL terminals, encompassing trajectory planning, PID calculation, microstepping control, and actual motor position feedback, jointly ensures smooth antenna trajectory and high tracking accuracy, and optimizes jitter during stepper motor control.

[0041] Furthermore, such as Figure 2 As shown, after receiving the target angle command from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back from the PL terminal at the PS terminal, and converting the target angle command into the target position of the stepper motor, the S-curve planner is used to periodically calculate the planned position based on the target position and the actual position of the stepper motor, and outputs the planned position at the current moment to the position-type PID controller; the position-type PID controller is used to perform differential calculation between the planned position and the actual position of the stepper motor at the current moment to obtain the position error, and outputs the target speed (Speed) and rotation direction (Dir) of the stepper motor to the PL terminal by performing PID calculation on the position error. Figure 2 Circles marked with an "×" indicate differential calculations. Trajectory planning refers to path planning based on the starting position of the stepper motor, assigning path timing information.

[0042] It should be understood that the S-curve planner can eliminate the rigid impact during motor start-up, shutdown, and speed changes, thus effectively solving the problems of high vibration and noise and low-speed crawling, ensuring the smoothness of the antenna's trajectory. The positional PID controller compares the planned position with the actual position at the current moment, and uses proportional, integral, and derivative operations to calculate the target speed and rotation direction to correct the deviation, thereby effectively suppressing external disturbances and internal system errors, ensuring the control accuracy of the motor.

[0043] Furthermore, the microstepping controller includes a speed control module, a microstepping lookup table module, and a microstepping control module. The speed control module is used to control the speed mode of the stepper motor based on the target speed and rotation direction output by the PS terminal. The microstepping lookup table module is used to look up the microstep number corresponding to the target speed and rotation direction in the microstepping table. The microstepping control module is connected to both the speed control module and the microstepping lookup table module. It is used to calculate the electrical angle based on the output of the speed control module and the microstepping lookup table module, calculate the optimized current based on the electrical angle, and finally generate four PWM pulse signals based on the optimized current and output them to the dual H-bridge driver chip.

[0044] It should be understood that a microstepping controller significantly improves the angular resolution of a stepper motor by subdividing a full step into hundreds or even thousands of microsteps. This effectively eliminates the vibration and noise associated with traditional full-step / half-step drives, resulting in extremely smooth operation and achieving higher-precision positioning control. Furthermore, it solves the "creeping" or "jamming" phenomenon that easily occurs when stepper motors operate at low speeds, ensuring uniform and smooth rotation at any low speed.

[0045] Furthermore, for two-phase stepper motors, rotation is typically driven directly using high and low voltage levels, and the control method employs four-beat control. Microstepping control technology can reduce or eliminate low-frequency vibrations in the stepper motor via a dual-bridge drive. Specifically, the four PWM pulse signals are divided into two groups, each group including positive and negative PWM pulse signals, corresponding to phase A: PWMA+ and PWMA-, and phase B: PWMB+ and PWMB-, respectively.

[0046] The PWM pulse signal value is calculated as follows:

[0047] Based on the given number of microsteps, the 360° electrical angle is divided into equal parts to obtain the electrical angle value of each microstep. Based on the electrical angle corresponding to the microstep number output by the microstep lookup module, the corresponding optimized current is generated. The value range of the optimized current is -1.0 to 1.0.

[0048] Determine the sign of the optimized current. When the current is greater than 0, configure the positive phase PWM pulse signal value in each group as the product of the optimized current and MAX_DUTY, and configure the negative phase PWM pulse signal value in each group as 0; otherwise, configure the positive phase PWM pulse signal value in each group as 0, and configure the negative phase PWM pulse signal value in each group as the product of the negative value of the optimized current and MAX_DUTY; where MAX_DUTY is the preset maximum duty cycle parameter of PWM.

[0049] Furthermore, the microstepping controller also includes a register set, which includes write registers and read registers, as shown in Table 1.

[0050] The write registers include a mode switching register, a PWM frequency register, a pulse increment register, a rotation direction register, a rotation speed register, and a configuration output register. These registers are used to receive external control commands and configure the motor drive's control / operating mode and PWM output frequency (corresponding to...). Figure 1 The output includes the period, number of motor rotation pulses, motor rotation direction, motor rotation speed, and output port function (i.e., configuring microsteps). The read registers include the remaining increment register and the resolver position value register, which are used to provide feedback to the outside world on the real-time operating status of the motor drive, including reading the remaining rotation pulses and the actual position data of the motor.

[0051] Table 1 Register set and related parameters

[0052]

[0053] Furthermore, the dual-channel rotary transformer is used to detect the actual position of the stepper motor; the rotary transformer decoding chip is connected to the dual-channel rotary transformer and is used to receive the output signal of the dual-channel rotary transformer for decoding, and output coarse and fine machine code values ​​representing the actual position of the stepper motor.

[0054] It should be understood that the dual-channel resolver provides high resolution through the precision machining channel and eliminates angular ambiguity through the coarse machining channel. Combining the two, extremely high-precision absolute angle values ​​of the motor can be obtained within a 360° range. The resolver decoding chip can quickly and accurately convert the analog signals from the dual-channel resolver into stable digital angle values ​​with a resolution down to the arcsecond level.

[0055] Furthermore, after receiving the coarse and fine machine code values ​​representing the actual position of the stepper motor periodically fed back from the PL end, the PS end also uses them for resolver coarse and fine machine combined error correction. The principle of resolver coarse and fine machine combined error correction is as follows: Figure 3 As shown, a combined error correction algorithm module is used to shift the last 12 bits of the coarse machine code value and compare it with the fine machine code value to determine whether the coarse machine code value is ahead or behind the fine machine code value. Then, the first four bits of the coarse machine code value are compensated or shifted back to obtain the first 4 bits of the error-corrected coarse machine code value. These 4 bits are then combined with the 16 bits of the fine machine code value to form a 20-bit resolution angle value, thus completing the error correction. The error-corrected angle value not only meets the angle bandwidth requirements but also ensures decoding accuracy.

[0056] Furthermore, the PS and PL terminals communicate via an FIC (Fiber Optic Interface Card) bus. The FIC supports high-speed data transmission.

[0057] In one embodiment, a spaceborne servo antenna control method based on heterogeneous FPGA is provided. This method is implemented based on the aforementioned spaceborne servo antenna control system based on heterogeneous FPGA, and includes the following steps:

[0058] First, at the PS end, based on the target angle command received from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back from the PL end, the S-curve planner and the position PID controller are controlled to perform motor trajectory planning and motor stepping speed calculation respectively, and the target speed and rotation direction of the stepper motor are output to the PL end.

[0059] Secondly, at the PL end, the microstepping controller is controlled to perform microstepping control of the motor step size according to the received target speed and rotation direction, and four PWM pulse signals are output to the dual H-bridge driver chip.

[0060] Next, the control antenna pointing mechanism of the stepper motor is rotated to the target angle by the dual H-bridge driver chip. After the dual-channel rotary transformer and the resolver decoding chip detect and output the actual position of the stepper motor, the coarse and fine machine code values ​​representing the actual position of the stepper motor are periodically collected by the PL terminal and fed back to the PS terminal to realize the closed-loop control of the rotation angle of the antenna pointing mechanism.

[0061] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application.

Claims

1. A spaceborne servo antenna control system based on heterogeneous FPGA, characterized in that, The system includes: a heterogeneous FPGA, an S-curve planner, a positional PID controller, a microstepping controller, a dual H-bridge driver chip, a stepper motor, a dual-channel rotary transformer, and a rotary transformer decoding chip; the heterogeneous FPGA includes a PS terminal and a PL terminal; the stepper motor is a two-phase type. The PS terminal is used to control the S-curve planner and the position-type PID controller to perform motor trajectory planning and motor step speed calculation respectively, based on the target angle command received from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back by the PL terminal, and output the target speed and rotation direction of the stepper motor to the PL terminal. The PL terminal is used to control the microstepping controller to perform microstepping control of the motor step size according to the received target speed and rotation direction, and output four PWM pulse signals to the dual H-bridge driver chip; after the dual H-bridge driver chip drives the control antenna pointing mechanism of the stepper motor to rotate towards the target angle, and after the dual-channel rotary transformer and the resolver decoding chip detect and output the actual position of the stepper motor, the PL terminal is also used to periodically collect the coarse and fine machine code values ​​representing the actual position of the stepper motor output by the resolver decoding chip, and feed them back to the PS terminal to realize closed-loop control of the rotation angle of the antenna pointing mechanism.

2. The spaceborne servo antenna control system based on heterogeneous FPGA according to claim 1, characterized in that, After receiving the target angle command from the antenna pointing mechanism at the PS terminal and the actual position of the stepper motor periodically fed back from the PL terminal, and converting the target angle command into the target position of the stepper motor, the S-curve planner is used to periodically calculate the planned position based on the target position and the actual position of the stepper motor, and outputs the planned position at the current moment to the position-type PID controller. The position-type PID controller is used to perform differential calculation between the planned position and the actual position of the stepper motor at the current moment to obtain the position error. By performing PID calculation on the position error, the target speed and rotation direction of the stepper motor are output to the PL terminal.

3. The spaceborne servo antenna control system based on heterogeneous FPGA according to claim 1, characterized in that, The microstep subdivision controller includes a speed control module, a microstep lookup table module, and a subdivision control module; The speed control module is used to control the speed mode of the stepper motor according to the target speed and rotation direction output by the PS terminal. The microstep lookup table module is used to look up the microstep number corresponding to the target speed and rotation direction in the microstep table; The subdivision control module is connected to the speed control module and the microstep lookup table module respectively. It is used to calculate the electrical angle based on the output result of the speed control module and the microstep sequence number output by the microstep lookup table module, calculate the optimized current based on the electrical angle, and finally generate four PWM pulse signals based on the optimized current and output them to the dual H-bridge driver chip.

4. The spaceborne servo antenna control system based on heterogeneous FPGA according to claim 3, characterized in that, The four PWM pulse signals are divided into two groups, each group including two PWM pulse signals: one in phase and one in reverse phase. The PWM pulse signal values ​​are calculated as follows: Based on the given number of microsteps, the 360° electrical angle is divided into equal parts to obtain the electrical angle value of each microstep. Based on the electrical angle corresponding to the microstep number output by the microstep lookup module, the corresponding optimized current is generated. The value range of the optimized current is -1.0 to 1.

0. Determine the sign of the optimized current. When the current is greater than 0, configure the positive phase PWM pulse signal value in each group as the product of the optimized current and MAX_DUTY, and configure the negative phase PWM pulse signal value in each group as 0. Otherwise, the positive phase PWM pulse signal value in each group is configured to 0, and the negative phase PWM pulse signal value in each group is configured to be the product of the negative value of the optimized current and MAX_DUTY; where MAX_DUTY is the preset maximum duty cycle parameter of PWM.

5. The spaceborne servo antenna control system based on heterogeneous FPGA according to claim 3, characterized in that, The microstepping controller also includes a register group, which includes a write register and a read register; The write register includes a mode switching register, a PWM frequency register, a pulse increment register, a rotation direction register, a rotation speed register, and a configuration output register. It is used to receive external control commands and configure the motor drive's control / operating mode, PWM output frequency, motor rotation pulse count, motor rotation direction, motor rotation speed, and output port functions. The read register includes a remaining increment register and a resolver position value register. It is used to provide feedback to the outside world on the real-time operating status of the motor drive, including reading the remaining rotation pulses and the actual position data of the motor.

6. The spaceborne servo antenna control system based on heterogeneous FPGA according to claim 1, characterized in that, The dual-channel rotary transformer is used to detect the actual position of the stepper motor; the rotary transformer decoding chip is connected to the dual-channel rotary transformer and is used to receive the output signal of the dual-channel rotary transformer for decoding, and output coarse and fine machine code values ​​representing the actual position of the stepper motor.

7. The spaceborne servo antenna control system based on heterogeneous FPGA according to claim 1, characterized in that, After receiving the coarse and fine machine code value representing the actual position of the stepper motor periodically fed back by the PL terminal, the PS terminal is also used to perform combined coarse and fine machine error correction for resolver. The error correction principle of the resolver roughing and finishing machine combination is as follows: The last 12 bits of the coarse machine code value are shifted and compared with the fine machine code value to determine whether the coarse machine code value is ahead or behind the fine machine code value. Then, the first four bits of the coarse machine code value are compensated or shifted back to obtain the first four bits of the corrected coarse machine code value. These four bits are then combined with the 16 bits of the fine machine code value to form a 20-bit resolution angle value, thus completing the error correction.

8. The spaceborne servo antenna control system based on heterogeneous FPGA according to claim 1, 2, or 7, characterized in that, The PS terminal and the PL terminal communicate via the FIC bus.

9. A method for controlling a spaceborne servo antenna based on a heterogeneous FPGA, characterized in that, The method is implemented based on the heterogeneous FPGA-based spaceborne servo antenna control system according to any one of claims 1-8, and includes the following steps: At the PS end, based on the target angle command received from the antenna pointing mechanism and the actual position of the stepper motor periodically fed back from the PL end, the S-curve planner and the position PID controller are controlled to perform motor trajectory planning and motor stepping speed calculation respectively, and the target speed and rotation direction of the stepper motor are output to the PL end. At the PL end, the microstepping controller is controlled to perform microstepping control of the motor step size based on the received target speed and rotation direction, and four PWM pulse signals are output to the dual H-bridge driver chip. The control antenna pointing mechanism of the stepper motor driven by the dual H-bridge driver chip rotates to the target angle. After the dual-channel rotary transformer and the resolver decoding chip detect and output the actual position of the stepper motor, the coarse and fine machine code values ​​representing the actual position of the stepper motor are periodically collected by the PL terminal and fed back to the PS terminal to realize closed-loop control of the rotation angle of the antenna pointing mechanism.

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