A magnetic suspension balance and mass measurement method based on a three-actuator structure

Abstract

The present invention relates to magnetic levitation measurement technology, specifically to a magnetic levitation balance and mass measurement method based on a three-actuator structure. The balance comprises a main housing, a magnetic levitation actuator, a reaction chamber, a displacement sensor, and hardware circuitry. The magnetic levitation actuator is a three-actuator structure consisting of three rotationally symmetrically distributed coils. The displacement sensor provides feedback on the position and posture of the actuator. A controller generates three drive signals, which are then amplified and fed into the three coils of the magnetic levitation actuator. This generates electromagnetic force to stabilize the actuator in the reaction chamber. The three currents are then measured and analyzed to determine the mass of the sample being measured. The magnetic levitation balance's actuator maintains stable levitation in complex reaction environments, avoiding mass measurement errors caused by spin or oscillation, and enabling non-contact, high-precision measurement of sample mass. ZYNQ technology is used to synchronize the three coils of the magnetic levitation actuator, miniaturizing the instrument.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic suspension measurement, and in particular relates to a magnetic suspension balance based on a three-actuator structure and a mass measurement method. Background Art

[0002] Due to its advantages of non-mechanical contact and high precision, magnetic levitation balances can replace mechanical levers and are ideal for high-precision mass monitoring of trace samples during chemical reactions. Currently, research on magnetic levitation balances for these applications is predominant abroad, while domestic research is relatively late and the technology is still immature.

[0003] The Discovery HP-TGA series thermogravimetric analyzers, developed by TA Instruments, utilize a drop-down magnetic suspension balance. This design transfers the weight of a sample within a pressure- and temperature-resistant reaction chamber to a balance outside the chamber via a magnetic coupling in a contactless manner. However, this system still relies on a traditional balance to measure the force acting on the stator to determine mass, requiring expensive strain gauges. Zeroing under varying operating conditions is very slow, and the noise generated during measurement is greater than with traditional mechanical couplings.

[0004] The Magnetic Mass Comparator (MSMC) developed by the National Institute of Standards and Technology (NIST) [1] , is designed to directly compare mass in air and mass in a vacuum for mass calibration. The MSMC does not use the voltage or current output of the controller to determine mass, but rather couples the magnetic suspension force between two weighing pans. Furthermore, the magnetic solenoids used for suspension are not fixed, allowing the weighing pans to swing freely and align with gravity. Any lateral constraint will introduce cosine-type errors.

[0005] In addition, during the sample reaction process, due to the complex environment in the reaction chamber, it may be affected by factors such as high temperature, high pressure, and airflow, causing the mover to spin or shake, thereby reducing the accuracy of mass measurement. Summary of the Invention

[0006] In response to the problems existing in the background technology, the present invention provides a magnetic suspension balance based on a three-actuator structure.

[0007] To solve the above technical problems, the present invention adopts the following technical solution: a magnetic levitation balance based on a three-actuator structure, including a balance main body shell, a reaction chamber, a magnetic levitation actuator, a sensing system and a hardware circuit: the magnetic levitation actuator is a three-actuator structure, which includes a stator and a mover, which are used to adjust the suspension position and posture of the mover; the sensing system is used to feedback the suspension gap of the mover; the hardware circuit includes a controller, a power management module, an A / D sampling module, a D / A conversion module, a voltage regulation module, a current measurement module, and a power amplifier and drive module, which are used for synchronous control of the magnetic levitation actuator.

[0008] In the above-mentioned magnetic levitation balance based on the three-actuator structure, the stator is installed on the top of the magnetic levitation balance and includes three coils, a stator permanent magnet, a coil cover, and a coil base. The stator permanent magnet and the coil cover are glued together, the three coils are glued together, and the coil cover and the coil base are connected by threads.

[0009] The upper part of the mover is T-shaped and the lower part is cylindrical, with rotational symmetry; it includes a mover permanent magnet, a mover permanent magnet mounting seat, a main connecting rod, a bearing, a bearing seat, a bearing end cover, three middle connecting rods, a loading tray, three lower connecting rods, and a mover lower end cover; the mover permanent magnet and its mounting seat are connected by interference fit, and the bearing end cover and the mover permanent magnet mounting seat are connected by threads; the mover is located in the reaction chamber.

[0010] In the above-mentioned magnetic levitation balance based on the three-actuator structure, the magnetic levitation balance further includes a balance main body housing and a reaction chamber;

[0011] The reaction chamber is sealed and has a sample delivery window, air inlet and air outlet for sample placement and gas circulation;

[0012] The main housing of the balance includes an optical platform, two adapter plates, two side panels and a top plate, all of which are connected by threads.

[0013] In the above-mentioned magnetic levitation balance based on the three-actuator structure, the sensing system includes three displacement sensors uniformly distributed on the top plate of the balance main body housing, and the three displacement sensors are distributed in rotational symmetry.

[0014] In the aforementioned magnetic levitation balance based on a three-actuator structure, the controller includes the ZYNQ minimum system and other peripheral circuits. The ZYNQ includes a processing system (PS) and a programmable logic (PL) terminal. The drivers for the A / D sampling module and D / A conversion module are located on the ZYNQ's PL terminal, using an FPGA for data acquisition and output. The ZYNQ's PS terminal performs magnetic levitation control and mass calculation functions, utilizing an ARM core for data operations and control instruction generation. The PS and PL terminals communicate via the on-chip AXI bus. The current measurement module is used to measure the current passing through the three coils.

[0015] In the aforementioned three-actuator magnetic levitation balance, the hardware circuit is powered by ±12V, generating a 5V analog power supply and a 3.3V digital power supply through voltage conversion. The D / A conversion module uses an ADC chip to measure analog voltages of different polarities across multiple channels and output digital signals. This signal communicates with the ZYNQ's power supply (PL) terminal using the SPI protocol, and the analog voltage input range for each channel is independently selectable via software. The A / D sampling module uses a DAC chip to convert the input digital signal into analog voltages of different polarities across multiple channels. This signal communicates with the ZYNQ's power supply (PL) terminal using the SPI protocol, and the internal reference voltage is programmable. The voltage regulation module, with an operational amplifier as its core component, amplifies the output voltage of the D / A conversion module by an appropriate multiple, outputting voltages of different polarities. The power amplifier and driver module uses a wideband, high-output current operational amplifier, the PA02, whose output power is used to drive the coil load. The current measurement module uses a current sensor to convert the drive current supplied to the coil into a voltage via a precision sampling resistor, which is then fed into the analog input channel of the A / D conversion module for measurement. The software program, located on the ZYNQ's power supply (PS), implements operational data collection, key parameter calculation, and suspension control.

[0016] In the aforementioned three-actuator magnetic levitation balance, the ZYNQ architecture includes: LCD_ctrl and adc_ctrl, dac_ctrl, and keyboard_ctrl custom IP cores located on the PL side for driving modules such as the LCD, ADC, DAC, and matrix keyboard; an ARM core and UART, GPIO, DDR3, QSPI, and SD controllers located on the PS side for running software programs; with the help of the AXI bus, the PS side transmits data with the PL side via the HP and GP interfaces, and the PL side interconnects the master and slave devices on the PL side via AXI Interconnect and AXISmartConnect; the PL side is used to drive the ADC, DAC, and keyboard, while the PS side is used to run software programs; the interface type of adc_ctrl, dac_ctrl, and keyboard_ctrl is AXI-Lite, which respectively implements communication with the ADC and DAC and the key detection function of the matrix keyboard, and exchanges data with the PS side; a timer interrupt is used to maintain the control frequency at 5kHz, and a UART is used for data interaction with the host computer.

[0017] A mass measurement method of a magnetic suspension balance based on a three-actuator structure, comprising:

[0018] When the three coils are energized, the stator generates an electromagnetic field, which is superimposed on the permanent magnetic field generated by the permanent magnet of the mover, generating an attractive force on the mover, causing it to levitate. The controller adjusts the current according to the displacement signal fed back by the displacement sensor, thereby changing the magnitude of the electromagnetic force to levitate the mover at a specified position.

[0019] When environmental factors in the reaction chamber interfere with the mover, the displacement sensor feeds back the mover's suspension position and posture information to the controller in real time. The controller then synchronously controls and adjusts the drive current of the three coils. By changing the electromagnetic force generated by one or more coils, the mover's suspension position and posture are adjusted to prevent it from spinning or shaking.

[0020] An intelligent filtering algorithm is used to suppress noise and interference, a zero-drift compensation algorithm is used to remove slowly changing trend items in the current, and the mass of the measured sample is inverted by analyzing the electromagnetic force generated by the three-way coil current to achieve sample mass measurement.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The magnetic levitation actuator of the present invention adopts three coils for synchronous control, which avoids the mass measurement error caused by spin or shaking while ensuring the stable suspension of the mover, thereby improving the mass measurement accuracy of the magnetic levitation balance.

[0023] (2) The present invention uses a small and high-precision displacement sensor that can detect the displacement of the mover at a fixed point, avoiding the inaccuracy of vertical position detection and achieving a miniaturized design of the instrument.

[0024] (3) The present invention adopts ZYNQ chip, which is smaller in size, has faster communication speed and stronger anti-interference ability compared with discrete ARM and FPGA solutions;

[0025] (4) The present invention rationally divides the work of each part of the ZYNQ chip to ensure the real-time control. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a three-dimensional diagram of a magnetic suspension balance body based on a three-actuator structure according to an embodiment of the present invention;

[0027] Figure 2 This is a front view of a magnetic levitation balance body based on a three-actuator structure according to an embodiment of the present invention;

[0028] Figure 3 This is an exploded diagram of the stator of a magnetic suspension balance based on a three-actuator structure according to an embodiment of the present invention;

[0029] Figure 4 This is an exploded diagram of a mover of a magnetic suspension balance based on a three-actuator structure according to an embodiment of the present invention;

[0030] Figure 5 This is a hardware circuit block diagram of a magnetic suspension balance based on a three-actuator structure according to an embodiment of the present invention;

[0031] Figure 6This is a ZYNQ architecture diagram of a magnetic levitation balance based on a three-actuator structure according to an embodiment of the present invention;

[0032] Among them, 1-optical platform, 2-adapter plate, 3-side panel, 4-top plate, 5-stator permanent magnet, 6-coil cover, 7-coil, 8-coil seat, 9-motor permanent magnet, 10-motor permanent magnet mounting seat, 11-motor main connecting rod, 12-bearing, 13-bearing seat, 14-bearing end cover, 15-middle connecting rod, 16-carrying tray, 17-lower connecting rod, 18-motor lower end cover, 19-displacement sensor, 20-reaction chamber, 21-sample delivery window, 22-air inlet, 23-air outlet. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0035] The present invention will be further described below with reference to specific examples, but they are not intended to limit the present invention.

[0036] This embodiment proposes a three-actuator structure and uses ZYNQ to achieve synchronous control of three coils. The drive currents of the three coils can be synchronously controlled and precisely adjusted. By varying the electromagnetic force generated by the coils, the actuator's suspension position and posture are adjusted to prevent spin or wobbling. This approach addresses the quality monitoring of trace samples during complex reactions. By analyzing the three coil currents to infer the mass of the measured sample, this approach overcomes the shortcomings of existing magnetic levitation balances, such as complex structure, high measurement noise, and low measurement accuracy, enabling non-contact, high-precision mass measurement in complex reaction environments.

[0037] This embodiment is implemented through the following technical solution: a magnetic levitation balance based on a three-actuator structure, comprising a balance housing, a magnetic levitation actuator, a reaction chamber, displacement sensors, and hardware circuitry. The magnetic levitation actuator, a three-actuator structure consisting of three rotationally symmetrically distributed coils, enables the mover to stably levitate without spinning or shaking in complex reaction environments. The hardware circuitry includes a power management module, a ZYNQ minimum system, an A / D sampling module, a D / A conversion module, a voltage regulation module, a current sensor, a power amplifier and driver module, and a peripheral interface. The ZYNQ chip comprises a processing system (PS) and programmable logic (PL). Three displacement sensors are used to measure the suspension gap of the magnetic levitation mover, and current sensors measure the drive current of the three coils.

[0038] In addition, the magnetic levitation actuator is a three-actuator structure containing three coils distributed in rotational symmetry, including a stator and a mover, and the whole has rotational symmetry; the stator is installed on the top of the magnetic levitation balance, including three coils, a stator permanent magnet, a coil cover and a coil seat, and the mover includes a permanent magnet, a loading tray and a connecting rod. The stator permanent magnet provides a certain static centering force for the mover; the mover is located in a closed reaction chamber, and the reaction chamber is provided with a sample delivery window, an air inlet and an air outlet for sample placement and gas circulation; the three-actuator structure can substantially reduce the stabilization time of the magnetic levitation balance, and can well overcome the measurement stability under the conditions of high temperature, high pressure and air flow in the reaction chamber.

[0039] In order to avoid mass measurement errors caused by the spin or shaking of the mover, the magnetic levitation actuator adopts a three-actuator structure consisting of three coils distributed in rotational symmetry. The three coils can be controlled synchronously to ensure the stable suspension of the mover.

[0040] The controller adjusts the driving current based on the position and attitude signals fed back by the current sensor to make the coil generate electromagnetic force of corresponding magnitude, so that the mover can be stably suspended without spinning or shaking.

[0041] The ZYNQ chip consists of a processing system (PS) and programmable logic (PL). The PS includes an ARM core, DDR, UART, MIO, and other components. The two components communicate via the on-chip AXI bus. The ZYNQ PL drives the A / D sampling and D / A conversion modules, utilizing the FPGA for real-time, high-speed data acquisition and output. The ZYNQ PS performs magnetic levitation control and mass calculation functions, utilizing the ARM core for data operations and control instruction generation.

[0042] There are three displacement sensors, which are small in size and have high measurement accuracy, and can collect the position and posture information of the mover in real time.

[0043] The current sensor can accurately measure the excitation current of the three coils.

[0044] When implementing it specifically, Figure 1 Figure 1 shows a magnetic levitation balance based on a three-actuator structure, comprising a balance housing, a magnetic levitation actuator, a reaction chamber, a displacement sensor, and hardware circuitry. The magnetic levitation actuator is a three-actuator structure consisting of three rotationally symmetrically distributed coils. The displacement sensor provides feedback on the position and posture of the actuator. A controller generates three drive signals, which are then amplified and fed into the three coils of the magnetic levitation actuator. This generates electromagnetic force to stabilize the actuator in the reaction chamber. The three currents are then measured and analyzed to determine the mass of the sample being measured. The three-actuator structure ensures stable levitation of the actuator in complex reaction environments, avoiding mass measurement errors caused by spin or oscillation of the actuator, thereby achieving non-contact, high-precision measurement of the sample mass. ZYNQ is used to synchronize the three coils of the magnetic levitation actuator, miniaturizing the instrument.

[0045] like Figure 2 As shown, a magnetic levitation balance based on a three-actuator structure includes a balance main body shell, a magnetic levitation actuator, a reaction chamber 20, a displacement sensor 19 and a hardware circuit. The position and posture of the mover are adjusted by adjusting the magnitude of the three driving currents to change the electromagnetic force, so that the mover equipped with the carrier tray 16 is suspended at a specified position without spinning or shaking, and the current is used to invert the mass of the sample being measured.

[0046] The front view of the magnetic levitation balance is as follows Figure 2 As shown, it consists of a balance main body shell, a reaction chamber 20 and a magnetic levitation actuator.

[0047] The main housing of the balance is composed of an optical platform 1, two adapter plates 2, two side panels 3 and a top plate 4, which are connected by threads.

[0048] The magnetic levitation actuator consists of two parts: the stator and the mover. The exploded diagrams of the stator and the mover are as follows: Figure 3 and Figure 4 As shown. The stator consists of a stator permanent magnet 5, a coil cover 6, three coils 7, and a coil base 8. The stator permanent magnet 5 is glued to the coil cover 6, the three coils 7 are glued to the coil base 8, and the coil cover 6 and coil base 8 are threaded. The mover is T-shaped at the top and cylindrical at the bottom, with rotational symmetry. It consists of a mover permanent magnet 9, a mover permanent magnet mounting base 10, a main connecting rod 11, a bearing 12, a bearing base 13, a bearing end cap 14, three middle connecting rods 15, a loading tray 16, three lower connecting rods 17, and a mover lower end cap 18. The mover permanent magnet 9 and its mounting base 10 are connected by an interference fit, and the bearing end cap 14 and the mover permanent magnet mounting base 10 are threaded.

[0049] There are three displacement sensors 19, which are evenly distributed on the top plate 4 of the balance main body shell, and feed back the suspension gap of the mover to the controller in real time.

[0050] Hardware circuit diagram as follows Figure 5 As shown, the system consists of the ZYNQ minimum system, power management module, A / D sampling module, D / A conversion module, power amplifier and driver module, current detection module, displacement sensor, and other peripheral circuits. The system uses a ±12V power supply, which can be converted to a 5V analog power supply and a 3.3V digital power supply through voltage conversion. The A / D sampling module uses an ADC chip to measure analog voltages of different polarities across multiple channels and output them as digital signals. It communicates with the ZYNQ's PL terminal using the SPI protocol, and the analog voltage input range for each channel is independently selectable via software. The D / A conversion module uses a DAC chip to convert input digital signals into analog voltages of different polarities across multiple channels. It communicates with the ZYNQ's PL terminal using the SPI protocol, and the internal reference voltage is programmable. The voltage regulation module, with an operational amplifier as its core component, amplifies the D / A conversion module's output voltage by an appropriate multiple, producing voltages of both positive and negative polarities. The power amplifier and driver module uses the wideband, high-output-current PA02 operational amplifier to provide sufficient power to drive the coil load. The current measurement module converts the drive current supplied to the coil into a voltage through a precision sampling resistor and feeds it into the analog input channel of the A / D conversion module for measurement. The software program, located on the PS side of the ZYNQ, collects operational data, calculates key parameters, and controls suspension, enabling high-precision mass measurement while ensuring stable suspension.

[0051] The architecture diagram of the ZYNQ chip is as follows Figure 6 As shown in the figure, the custom IP cores, such as LCD_ctrl and adc_ctrl, dac_ctrl, and keyboard_ctrl, are located on the PL side and drive modules such as the LCD, ADC, DAC, and matrix keyboard. The ARM core, along with the UART, GPIO, DDR3, QSPI, and SD controllers, are located on the PS side and are responsible for running the software. The PS side uses the AXI bus to exchange data with the PL side via the HP and GP interfaces. The PL side interconnects the master and slave devices on the PL side via AXI Interconnect and AXI SmartConnect. The PL side primarily drives peripherals such as the ADC, DAC, and keyboard, while the PS side runs the software. The adc_ctrl, dac_ctrl, and keyboard_ctrl interfaces are AXI-Lite, respectively implementing communication with the ADC and DAC and key detection for the matrix keyboard, and enabling data exchange with the PS side. Timer interrupts are used to maintain the control frequency at 5kHz, and UART is used for data exchange with the host computer.

[0052] The operating principle and process of this embodiment are as follows: When coil 7 is energized, the stator generates an electromagnetic field, which, combined with the permanent magnetic field generated by the mover's permanent magnet 9, exerts an attractive force on the mover, causing it to levitate. The controller adjusts the current based on the displacement signal fed back by the displacement sensor 19, thereby varying the magnitude of the electromagnetic force to levitate the mover at a specified position. When environmental factors in the reaction chamber interfere with the mover, the displacement sensor 19 provides real-time feedback of the mover's levitation position and posture to the controller. The controller synchronously controls and precisely adjusts the drive currents of the three coils, adjusting the levitation position and posture of the mover by varying the electromagnetic force generated by one or more coils to prevent spin or wobbling. Simultaneously, an intelligent filtering algorithm is employed to suppress noise and interference, a zero-drift compensation algorithm is employed to remove slowly varying trend terms in the current, and the mass of the sample being measured is inverted by analyzing the electromagnetic forces generated by the three coil currents, achieving high-precision measurement of the sample's mass.

[0053] The above are only preferred embodiments of the present invention and do not limit the implementation mode and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the contents of the present invention specification should be included in the protection scope of the present invention.

[0054] References:

[0055] [1]VLAJIC N, DAVIS M, STAMBAUGH C. Nanometer positional control using magnetic suspension for vacuum-to-air mass metrology[J]. Journal of DynamicSystems, Measurement and Control, Transactions of the ASME, 2018, 140(12).

Claims

1. A magnetic suspension balance based on a three-actuator structure, characterized in that: The system includes a balance body housing, a reaction chamber, a magnetic levitation actuator, a sensor system, and hardware circuits. The magnetic levitation actuator is a three-actuator structure consisting of a stator and a mover, which are used to adjust the mover's suspension position and posture. The sensor system is used to provide feedback on the mover's suspension gap. The hardware circuit includes a controller, a power management module, an A / D sampling module, a D / A conversion module, a voltage regulation module, a current measurement module, and a power amplifier and drive module for synchronous control of the magnetic levitation actuator. The stator is installed on the top of the magnetic suspension balance and includes three coils, a stator permanent magnet, a coil cover, and a coil base. The stator permanent magnet and the coil cover are glued together, the three coils are glued together, and the coil cover and the coil base are connected by threads. The upper part of the mover is T-shaped and the lower part is cylindrical, with rotational symmetry; it includes a mover permanent magnet, a mover permanent magnet mounting seat, a main connecting rod, a bearing, a bearing seat, a bearing end cover, three middle connecting rods, a loading tray, three lower connecting rods, and a mover lower end cover; the mover permanent magnet and its mounting seat are connected by interference fit, and the bearing end cover and the mover permanent magnet mounting seat are connected by threads; the mover is located in the reaction chamber.

2. The magnetic suspension balance based on the three-actuator structure according to claim 1, characterized in that: The magnetic levitation balance also includes a balance main body shell and a reaction chamber; The reaction chamber is sealed and has a sample delivery window, air inlet and air outlet for sample placement and gas circulation; The main housing of the balance includes an optical platform, two adapter plates, two side panels and a top plate, all of which are connected by threads.

3. The magnetic suspension balance based on the three-actuator structure according to claim 1, characterized in that: The sensing system includes three displacement sensors that are evenly distributed on the top plate of the balance main body shell, and the three displacement sensors are distributed in rotational symmetry.

4. The magnetic suspension balance based on a three-actuator structure according to claim 1, characterized in that: The controller includes the ZYNQ minimum system and other peripheral circuits; ZYNQ includes a processing system PS side and a programmable logic PL side; the drivers of the A / D sampling module and D / A conversion module are located on the ZYNQ PL side, using FPGA to realize data acquisition and output; the ZYNQ PS side completes the magnetic levitation control and mass calculation functions, using the ARM core to realize data calculation and control instruction generation; the PS side and the PL side communicate through the on-chip AXI bus; the current measurement module is used to measure the current passing through the three coils.

5. The magnetic suspension balance based on the three-actuator structure according to claim 4, characterized in that: The hardware circuit is powered by ±12 V, with voltage conversion resulting in a 5 V analog power supply and a 3.3 V digital power supply. The D / A conversion module uses an ADC chip to measure analog voltages of different polarities across multiple channels and output digital signals. This signal communicates with the ZYNQ's PL terminal using the SPI protocol, with the analog voltage input range of each channel independently selectable via software. The A / D sampling module uses a DAC chip to convert the input digital signal into analog voltages of different polarities across multiple channels. This signal communicates with the ZYNQ's PL terminal using the SPI protocol, with the internal reference voltage programmable. The voltage regulation module, with an operational amplifier as its core component, amplifies the D / A conversion module's output voltage by an appropriate factor, outputting voltages of varying polarity. The power amplifier and driver module uses the broadband, high-output-current PA02 operational amplifier, whose output power is used to drive the coil load. The current measurement module uses a current sensor to convert the coil's drive current into a voltage via a precision sampling resistor, which is then fed into the A / D conversion module's analog input channel for measurement. The software, located on the ZYNQ's PS terminal, enables operational data acquisition, key parameter calculation, and suspension control.

6. The magnetic suspension balance based on the three-actuator structure according to claim 4, characterized in that: The ZYNQ architecture includes: LCD_ctrl and adc_ctrl, dac_ctrl, and keyboard_ctrl custom IP cores are located on the PL side, used to drive modules such as the LCD, ADC, DAC, and matrix keyboard; the ARM core and UART, GPIO, DDR3, QSPI, and SD controllers are located on the PS side, used to run software programs; with the help of the AXI bus, the PS side transmits data with the PL side through the HP and GP interfaces, and the PL side completes the interconnection between the PL side master and slave devices through AXIInterconnect and AXI SmartConnect; the PL side is used to drive the ADC, DAC, and keyboard, and the PS side is used to run software programs; the interface type of adc_ctrl, dac_ctrl, and keyboard_ctrl is AXI-Lite, which respectively implements communication with the ADC and DAC and the key detection function of the matrix keyboard, and exchanges data with the PS side; a timer interrupt is used to maintain the control frequency at 5 kHz, and UART is used for data interaction with the host computer.

7. The mass measurement method of a magnetic suspension balance based on a three-actuator structure according to any one of claims 1 to 6, characterized in that: include: When the three coils are energized, the stator generates an electromagnetic field, which is superimposed on the permanent magnetic field generated by the permanent magnet of the mover, generating an attractive force on the mover and causing it to levitate. The controller adjusts the current according to the displacement signal fed back by the displacement sensor, thereby changing the magnitude of the electromagnetic force to make the mover levitate at the specified position; When environmental factors in the reaction chamber interfere with the mover, the displacement sensor feeds back the mover's suspension position and posture information to the controller in real time. The controller then synchronously controls and adjusts the drive current of the three coils. By changing the electromagnetic force generated by one or more coils, the mover's suspension position and posture are adjusted to prevent it from spinning or shaking. An intelligent filtering algorithm is used to suppress noise and interference, a zero-drift compensation algorithm is used to remove slowly changing trend items in the current, and the mass of the measured sample is inverted by analyzing the electromagnetic force generated by the three-way coil current to achieve sample mass measurement.

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