A charge management device and method based on disturbance observer sliding mode control

Abstract

The present invention discloses a charge management device and method based on disturbance observer sliding mode control, belonging to the field of high-precision inertial sensors. An AC driving voltage is applied to the parallel plates in the horizontal direction, and the displacement signal of the proof mass is measured and converted into a voltage signal; the charge measurement module converts this voltage signal into the charge value of the proof mass, and subtracts the charge value of the proof mass from the set charge value to obtain a charge error signal, and at the same time inputs the charge error signal into the disturbance observer sliding mode control module; subsequently, the charge and discharge rate required to control to the set charge value is calculated; the ultraviolet light irradiation module is driven according to the charge and discharge rate, and the bias voltage is respectively applied to the parallel plates on both sides in the vertical direction to control the charge of the proof mass to the set charge value. The present invention can still achieve precise control of the charge of the proof mass when there are external disturbances or parameter changes, and can provide good charge closed-loop control and robustness.

Description

Technical Field

[0001] The present invention belongs to the field of high-precision inertial sensors, and particularly relates to a charge management device and method based on disturbance observer sliding mode control. Background Art

[0002] In the field of high-precision inertial sensors (such as gravitational wave detection), in the sensitive axis direction, the displacement measurement module of the inertial sensor detects the relative displacement between the test mass (TM) and the satellite with extremely high sensitivity. The displacement change information is transmitted to the satellite's thruster system, and the thruster applies precise thrust to make the satellite follow the movement of the test mass, ensuring that the relative position between the two remains unchanged. In this state, the test mass serves as the inertial reference point for laser interferometry, and by measuring the relative displacement change between it and the satellite, the detection of gravitational waves is achieved.

[0003] However, high-energy particles and cosmic rays in the universe will cause the test mass to gradually accumulate charges, thereby generating electrostatic forces between its surface and surrounding conductors, interfering with the measurement accuracy. Therefore, it is necessary to effectively control the charges on the test mass. Taking the charge management scheme adopted in LISA Pathfinder as an example, its core method is to use ultraviolet light irradiation to make electrons enter or escape from the test mass or the surrounding electrode plates through the photoelectric effect, thereby quickly reducing the surface charge to the desired level. However, due to reasons such as perturbations in the cosmic space environment, optical power attenuation, and changes in the physical properties of the conductor surface, it is necessary to accurately measure the charge quantity of the conductor before implementing the light irradiation, which poses extremely high technical challenges to actual operations. Summary of the Invention

[0004] The purpose of the present invention is to provide a charge management device and method based on disturbance observer sliding mode control in view of the deficiencies of the prior art.

[0005] The purpose of the present invention is achieved through the following technical solutions: A charge management device based on disturbance observer sliding mode control, the device includes: a test mass, parallel plates, an ultraviolet light irradiation module, a displacement measurement module, a charge measurement module, a disturbance observer sliding mode control module, and a charge execution machine module;

[0006] The parallel plates are placed in the horizontal and vertical directions of the test mass, parallel to the surface of the test mass, all parallel plates are parallel to the test mass and at equal distances, the number of parallel plates placed on both sides of the test mass in the horizontal direction is the same, and the number of parallel plates placed on both sides of the test mass in the vertical direction is the same;

[0007] The output ends of the parallel plates in the horizontal direction are connected to the displacement measurement module; the output of the displacement measurement module is connected to the charge measurement module; one output end of the charge measurement module is connected to the disturbance observer sliding mode control module, and the other output end is subtracted from the input set charge value to obtain a charge error signal; the charge error signal is input into the disturbance observer sliding mode control module; the output end of the disturbance observer sliding mode control module is connected to the input end of the charge actuator module; the output end of the charge actuator is connected to the ultraviolet light irradiation module;

[0008] The disturbance observer sliding mode control module includes a disturbance observer, a sliding mode control module and a disturbance observation control module.

[0009] Furthermore, the parallel plates in the horizontal direction are used to receive an AC drive voltage, so that the test mass rotates, and the magnitudes of the AC drive voltages applied to the adjacent parallel plates on the same side are equal and the directions are opposite;

[0010] The parallel plates in the vertical direction are used to apply a bias voltage;

[0011] The ultraviolet light irradiation module includes a first ultraviolet irradiation sub-module, a second ultraviolet irradiation sub-module, a third ultraviolet irradiation sub-module and a fourth ultraviolet irradiation sub-module;

[0012] The displacement measurement module is used to measure the displacement of the test mass relative to the parallel plates in the horizontal direction, convert the displacement into a voltage signal and transmit it to the charge measurement module;

[0013] The charge measurement module is used to receive the voltage signal, calculate the charge value of the test mass according to the voltage signal and input it into the disturbance observer sliding mode control module; at the same time, subtract the calculated charge value of the test mass from the set charge value to obtain a charge error signal and input it into the disturbance observer sliding mode control module;

[0014] The disturbance observer sliding mode control module is used to receive the charge value of the test mass, the set charge value and the charge error signal, and calculate the charge and discharge rate required to control the charge of the test mass to the set charge value based on the charge on-orbit charge and discharge model and input it into the charge actuator module;

[0015] The charge actuator module is used to receive the charge and discharge rate, drive the ultraviolet light irradiation module to irradiate the parallel plates in the vertical direction or the surface of the test mass, and apply bias voltages with the same magnitude and opposite directions to the parallel plates on both sides in the vertical direction respectively to control the charge of the test mass to the set charge value.

[0016] Furthermore, the number of the parallel plates is 6, including 4 parallel plates in the horizontal direction and 2 parallel plates in the vertical direction;

[0017] The four horizontally parallel plates are respectively a first parallel plate, a second parallel plate, a third parallel plate and a fourth parallel plate; the first parallel plate and the third parallel plate are located on one side of the test mass in the horizontal direction, and the second parallel plate and the fourth parallel plate are located on the other side of the test mass in the horizontal direction; the first parallel plate is parallel and opposite to the second parallel plate; the third parallel plate is parallel and opposite to the fourth parallel plate;

[0018] The two vertically parallel plates are respectively a fifth parallel plate and a sixth parallel plate; the fifth parallel plate is located on one side of the test mass in the vertical direction, and the sixth parallel plate is located on the other side of the test mass in the vertical direction; the fifth parallel plate is parallel and opposite to the sixth parallel plate.

[0019] Further, the driving ultraviolet light irradiation module irradiates the vertically parallel plates or the surface of the test mass, specifically:

[0020] Drive the first ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the parallel plate on one side in the vertical direction, drive the second ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the surface of the test mass opposite to the parallel plate on one side in the vertical direction, drive the third ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the parallel plate on the other side in the vertical direction, and drive the fourth ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the surface of the test mass opposite to the parallel plate on the other side in the vertical direction.

[0021] The present invention also provides a charge management method based on disturbance observer sliding mode control, which is applied to the above-mentioned charge management device based on disturbance observer sliding mode control, and includes the following steps:

[0022] Parallel plates are respectively placed in the horizontal and vertical directions of the test mass. Among them, all parallel plates are parallel to the test mass and have equal distances. The number of parallel plates placed on both sides of the test mass in the horizontal direction is the same, and the number of parallel plates placed on both sides of the test mass in the vertical direction is the same;

[0023] Apply AC driving voltages with the same magnitude and opposite directions to the parallel plates in the horizontal direction of the test mass respectively, drive the test mass to rotate, measure the displacement of the test mass relative to the parallel plates in the horizontal direction through the displacement measurement module, and convert this displacement into a voltage signal and transmit it to the charge measurement module;

[0024] The charge measurement module calculates the charge value of the test mass from the voltage signal and inputs it into the disturbance observer sliding mode control module. At the same time, the difference between the calculated charge value of the test mass and the set charge value is used as a charge error signal and input into the disturbance observer sliding mode control module;

[0025] The interference observer sliding mode control module receives the charge value of the test mass, the set charge value, and the charge error signal, and based on the on-orbit charge charging and discharging model, calculates the charging and discharging rate required to control the charge of the test mass to the set charge value and inputs it to the charge actuator module;

[0026] The charge actuator module receives the charging and discharging rate, drives the ultraviolet light irradiation module to irradiate the parallel plates in the vertical direction or the surface of the test mass, and applies bias voltages of the same magnitude and opposite directions to the parallel plates on both sides in the vertical direction to control the charge of the test mass to the set charge value.

[0027] Further, the on-orbit charge charging and discharging model is , where represents the attenuation coefficient of the actual charging rate of the test mass in space; is the charge value of the test mass; is the derivative of the charge value of the test mass; represents the charging and discharging rate output by the sliding mode control module; represents the attenuation coefficient of the ultraviolet light charging and discharging rate of the actual model; represents the unknown disturbance from the outside;

[0028] The charging and discharging rate output by the sliding mode control module is , where represents the charge error signal, represents the sign function, represents the first gain coefficient of the sliding mode control module, represents the second gain coefficient of the sliding mode control module, represents the sliding mode surface switching function; The sliding mode surface switching function is , where represents the gain coefficient;

[0029] The output of the interference observer is ;

[0030] where represents the estimation of the external unknown disturbance , represents the derivative of the estimation of the external unknown disturbance, represents the estimation of the charge value of the test mass, is the derivative of the estimation of the charge value of the test mass, represents the charging and discharging rate output by the interference observation control module in the interference observer sliding mode control module, represents the first gain coefficient of the interference observer, represents the second gain coefficient of the interference observer;

[0031] The charging and discharging rate output by the interference observation control module is .

[0032] The present invention also provides a charge management device based on interference observation sliding mode control, including one or more processors for implementing the above-mentioned charge management method based on interference observation sliding mode control.

[0033] The present invention also provides a computer-readable storage medium with a program stored thereon, which is used to implement the above-mentioned charge management method based on interference observation sliding mode control when executed by a processor.

[0034] The beneficial effects of the present invention are as follows: In the present invention, the interference sliding mode control module can effectively estimate the unknown external disturbances and automatically adjust the control parameters. When the external environment is disturbed or the charging and discharging physical characteristics of the conductor itself change, there is no need to interrupt the target signal detection to re-measure the external charging rate, avoiding the interference problem caused by interrupting the target signal detection when measuring the cumulative charge for inspection quality, and having a wide application prospect. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flowchart of a charge management method based on interference observation sliding mode control in Embodiment 2;

[0036] Figure 2 is a structural diagram of the interference observation sliding mode control module in Embodiment 2;

[0037] Figure 3 is a schematic structural diagram of a charge management device based on interference observation sliding mode control in Embodiment 3;

[0038] Figure 4 is a schematic diagram of the mechanical structure in a charge management device based on interference observation sliding mode control in Embodiment 3;

[0039] Figure 5 is a schematic structural diagram of a charge management device based on interference observation sliding mode control in Embodiment 4. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0040] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the protection scope of the present invention.

[0041] Embodiment 1: The present invention provides a charge management device based on disturbance observer sliding mode control. The device includes: a proof mass, parallel plates, an ultraviolet light irradiation module, a displacement measurement module, a charge measurement module, a disturbance observer sliding mode control module, and a charge actuator module.

[0042] The parallel plates in the horizontal direction are used to receive an AC driving voltage, causing the proof mass to rotate, and the magnitudes of the AC driving voltages applied to the adjacent parallel plates on the same side are equal and the directions are opposite.

[0043] The parallel plates in the vertical direction are used to apply a bias voltage.

[0044] The ultraviolet light irradiation module includes a first ultraviolet irradiation sub-module, a second ultraviolet irradiation sub-module, a third ultraviolet irradiation sub-module, and a fourth ultraviolet irradiation sub-module.

[0045] The displacement measurement module is used to measure the displacement of the proof mass relative to the parallel plates in the horizontal direction, convert the displacement into a voltage signal, and transmit the voltage signal to the charge measurement module.

[0046] The charge measurement module is used to receive the voltage signal and calculate the charge value of the proof mass and input it to the disturbance observer sliding mode control module; at the same time, subtract the calculated charge value of the proof mass from the set charge value to obtain a charge error signal : and input it to the disturbance observer sliding mode control module.

[0047] The disturbance observer sliding mode control module is used to receive the charge value of the proof mass , the set charge value , and the charge error signal , and calculate, based on the charge on-orbit charge and discharge model, the charge and discharge rate required to control the charge of the proof mass to the set charge value and input it to the charge actuator module.

[0048] The charge actuator module is used to receive the charge and discharge rate , drive the ultraviolet light irradiation module to irradiate the parallel plates in the vertical direction or the surface of the proof mass, and apply bias voltages with the same magnitude and opposite directions to the parallel plates on both sides in the vertical direction respectively, so as to control the charge of the proof mass to the set charge value .

[0049] The number of the parallel plates is 6, including 4 parallel plates in the horizontal direction and 2 parallel plates in the vertical direction.

[0050] The four horizontally parallel plates are respectively a first parallel plate, a second parallel plate, a third parallel plate and a fourth parallel plate; the first parallel plate and the third parallel plate are located on one side of the test mass in the horizontal direction, and the second parallel plate and the fourth parallel plate are located on the other side of the test mass in the horizontal direction; the first parallel plate is parallel and opposite to the second parallel plate; the third parallel plate is parallel and opposite to the fourth parallel plate.

[0051] The two vertically parallel plates are respectively a fifth parallel plate and a sixth parallel plate; the fifth parallel plate is located on one side of the test mass in the vertical direction, and the sixth parallel plate is located on the other side of the test mass in the vertical direction; the fifth parallel plate is parallel and opposite to the sixth parallel plate.

[0052] Embodiment 2: As Figure 1 shown, the present invention also provides a charge management method based on disturbance observer sliding mode control, including the following steps:

[0053] Place parallel plates in the horizontal and vertical directions of the test mass respectively, wherein all the parallel plates are parallel to the test mass and have equal distances, the number of parallel plates placed on both sides of the test mass in the horizontal direction is the same, and the number of parallel plates placed on both sides of the test mass in the vertical direction is the same.

[0054] Apply AC drive voltages with the same magnitude and opposite directions to the parallel plates in the horizontal direction of the test mass respectively, drive the test mass to rotate, measure the displacement of the test mass relative to the parallel plates in the horizontal direction through a displacement measurement module, and convert the displacement into a voltage signal and transmit it to a charge measurement module.

[0055] The charge measurement module calculates the charge value of the test mass from the voltage signal and inputs it to the disturbance observer sliding mode control module. At the same time, the difference between the calculated charge value of the test mass and the set charge value is used as a charge error signal and input to the disturbance observer sliding mode control module.

[0056] The disturbance observer sliding mode control module receives the charge value of the test mass, the set charge value and the charge error signal, and calculates the charge and discharge rate required to control the charge of the test mass to the set charge value based on the on-orbit charge and discharge model of the charge, and inputs it to the charge actuator module.

[0057] The charge actuator module receives the charge and discharge rate, drives the ultraviolet light irradiation module to irradiate the parallel plates in the vertical direction or the surface of the test mass, and applies bias voltages with the same magnitude and opposite directions and to the parallel plates on both sides in the vertical direction respectively, and controls the charge of the test mass to the set charge value.

[0058] As Figure 2 shown, the disturbance observer sliding mode control module includes a disturbance observer, a sliding mode control module, and a disturbance observer control module.

[0059] The on-orbit charge charging and discharging model is , where represents the attenuation coefficient of the actual charging rate of the test mass in space; is the charge value of the test mass; is the derivative of the charge value of the test mass; represents the charging and discharging rate output by the sliding mode control module; represents the attenuation coefficient of the ultraviolet light charging and discharging rate of the actual model; represents the unknown disturbance from the outside world.

[0060] The charging and discharging rate output by the sliding mode control module is , where represents the charge error signal, represents the sign function, represents the first gain coefficient of the sliding mode control module, represents the second gain coefficient of the sliding mode control module, represents the sliding mode surface switching function; the sliding mode surface switching function is , where represents the gain coefficient.

[0061] The output of the disturbance observer is ;

[0062] where represents the estimation of the unknown disturbance from the outside world , represents the derivative of the estimation of the unknown disturbance from the outside world, represents the estimation of the charge value of the test mass, is the derivative of the estimation of the charge value of the test mass, represents the charging and discharging rate output by the disturbance observer control module in the disturbance observer sliding mode control module, represents the first gain coefficient of the disturbance observer, represents the second gain coefficient of the disturbance observer.

[0063] The input of the disturbance observer is the charge value of the test mass , and the charging and discharging rate output by the disturbance observer control module is , according to , it can be obtained that: ; then is substituted into , and it can be obtained that , in this formula, only is an unknown quantity, and the rest are known quantities, then can be obtained. Then, according to , is obtained.

[0064] The charge and discharge rate output by the disturbance observation control module is .

[0065] Embodiment 3: As Figure 3 shown, the present invention provides a charge management device based on disturbance observation sliding mode control. The device includes: a mechanical structure, a displacement measurement module, a charge measurement module, a disturbance observation sliding mode control module, and a charge actuator module.

[0066] The mechanical structure in a charge management device based on disturbance observation sliding mode control is as Figure 4 shown. The mechanical structure includes a proof mass (TM), parallel plates, and an ultraviolet light irradiation module. In this embodiment, the number of the parallel plates is 6, including 4 horizontally arranged parallel plates and 2 vertically arranged parallel plates.

[0067] The 4 horizontally arranged parallel plates are respectively a first parallel plate , a second parallel plate , a third parallel plate , and a fourth parallel plate ; the first parallel plate and the third parallel plate are located on one side of the proof mass in the horizontal direction, and the second parallel plate and the fourth parallel plate are located on the other side of the proof mass in the horizontal direction; the first parallel plate and the second parallel plate are parallel and opposite to each other; the third parallel plate and the fourth parallel plate are parallel and opposite to each other.

[0068] The 2 vertically arranged parallel plates are respectively a fifth parallel plate and a sixth parallel plate ; the fifth parallel plate is located on one side of the proof mass in the vertical direction, and the sixth parallel plate is located on the other side of the proof mass in the vertical direction; the fifth parallel plate and the sixth parallel plate are parallel and opposite to each other.

[0069] The output ends of the first parallel plate , the second parallel plate , the third parallel plate , and the fourth parallel plate , , , and in the mechanical structure are respectively connected to the displacement measurement module.

[0070] The ultraviolet light irradiation module includes a first ultraviolet irradiation sub-module UV light 1, a second ultraviolet irradiation sub-module UV light 2, a third ultraviolet irradiation sub-module UV light 3, and a fourth ultraviolet irradiation sub-module UV light 4.

[0071] The charge actuator module is respectively connected to the first ultraviolet irradiation sub-module UV light 1, the second ultraviolet irradiation sub-module UV light 2, the third ultraviolet irradiation sub-module UV light 3, and the fourth ultraviolet irradiation sub-module UV light 4, and is used to drive the first ultraviolet irradiation sub-module UV light 1 to emit ultraviolet light to irradiate the parallel plate on one side in the vertical direction, drive the second ultraviolet irradiation sub-module UV light 2 to emit ultraviolet light to irradiate the surface of the test mass opposite to the parallel plate on one side in the vertical direction, drive the third ultraviolet irradiation sub-module UV light 3 to emit ultraviolet light to irradiate the parallel plate on the other side in the vertical direction, and drive the fourth ultraviolet irradiation sub-module UV light 4 to emit ultraviolet light to irradiate the surface of the test mass opposite to the parallel plate on the other side in the vertical direction.

[0072] The output of the displacement measurement module is connected to the charge measurement module; one output terminal of the charge measurement module is connected to the disturbance observer sliding mode control module, and the other output terminal is subtracted from the input set charge value to obtain a charge error signal; the charge error signal is input to the disturbance observer sliding mode control module; the output terminal of the disturbance observer sliding mode control module is connected to the input terminal of the charge actuator module; the output terminal of the charge actuator is connected to the ultraviolet light irradiation module.

[0073] Embodiment 4: Corresponding to Embodiment 2 of the foregoing charge management method based on disturbance observer sliding mode control, the present invention further provides an embodiment of a charge management device based on disturbance observer sliding mode control.

[0074] See Figure 5 , a charge management device based on disturbance observer sliding mode control provided by an embodiment of the present invention includes one or more processors for implementing a charge management method based on disturbance observer sliding mode control in the foregoing embodiment.

[0075] An embodiment of the charge management device based on disturbance observer sliding mode control of the present invention can be applied to any device with data processing capabilities, and such a device with data processing capabilities can be a device or apparatus such as a computer. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. Taking software implementation as an example, as a logically meaningful device, it is formed by the processor of any device with data processing capabilities where it is located reading the corresponding computer program instructions in the non-volatile memory into the memory for operation. From the hardware level, as Figure 5 shown, it is a hardware structure diagram of any device with data processing capabilities where the charge management device based on disturbance observer sliding mode control of the present invention is located. In addition to Figure 5 the processor, memory, network interface, and non-volatile memory shown, for any device with data processing capabilities where the device in the embodiment is located, usually according to the actual functions of the device with data processing capabilities, it may also include other hardware, which will not be elaborated here.

[0076] For the implementation processes of the functions and roles of each unit in the above device, please refer to the implementation processes of the corresponding steps in the above method for details, which will not be elaborated here.

[0077] For the device embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they can be located in one place, or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of the present invention. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0078] An embodiment of the present invention also provides a computer-readable storage medium, on which a program is stored. When the program is executed by a processor, it implements a charge management method based on disturbance observer sliding mode control in the above embodiment. The computer-readable storage medium may be an internal storage unit of any device with data processing capabilities described in any of the foregoing embodiments, such as a hard disk or memory. The computer-readable storage medium may also be an external storage device of any device with data processing capabilities, such as a plug-in hard disk, a Smart Media Card (SMC), an SD card, a Flash Card, etc. equipped on the device. Further, the computer-readable storage medium may also include both an internal storage unit and an external storage device of any device with data processing capabilities. The computer-readable storage medium is used to store the computer program and other programs and data required by any device with data processing capabilities, and may also be used to temporarily store data that has been output or is to be output.

[0079] The foregoing is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A charge management device based on disturbance observer sliding mode control, characterized in that The device includes: a test mass, parallel plates, an ultraviolet light irradiation module, a displacement measurement module, a charge measurement module, a disturbance observer sliding mode control module, and a charge actuator module; The parallel plates are placed in the horizontal and vertical directions of the test mass, parallel to the surface of the test mass. All parallel plates are parallel to the test mass and at equal distances. The number of parallel plates placed on both sides of the test mass in the horizontal direction is the same, and the number of parallel plates placed on both sides of the test mass in the vertical direction is the same; The output ends of the parallel plates in the horizontal direction are connected to the displacement measurement module; the output of the displacement measurement module is connected to the charge measurement module; one output end of the charge measurement module is connected to the disturbance observer sliding mode control module, and the other output end is subtracted from the input set charge value to obtain a charge error signal; the charge error signal is input to the disturbance observer sliding mode control module; the output end of the disturbance observer sliding mode control module is connected to the input end of the charge actuator module; the output end of the charge actuator is connected to the ultraviolet light irradiation module; The disturbance observer sliding mode control module includes a disturbance observer, a sliding mode control module, and a disturbance observer control module The output of the disturbance observer is ; Among them, represents the estimation of the external unknown disturbance , represents the derivative of the estimation of the external unknown disturbance, is the charge value for testing the quality, represents the attenuation coefficient of the actual charging rate of the test mass in space, represents the estimation of the charge value of the test mass, is the derivative of the estimation of the charge value of the test mass, represents the charge and discharge rate output by the disturbance observation control module in the disturbance observation sliding mode control module, represents the ultraviolet light charge and discharge rate attenuation coefficient of the actual model, represents the first gain coefficient of the disturbance observer, represents the second gain coefficient of the disturbance observer.

2. The charge management device based on disturbance observer sliding mode control according to claim 1, characterized in that The parallel plates in the horizontal direction are used to receive an AC driving voltage, so that the test mass rotates, and the magnitudes of the AC driving voltages applied to the adjacent parallel plates on the same side are equal and the directions are opposite; The parallel plates in the vertical direction are used to apply a bias voltage; The ultraviolet light irradiation module includes a first ultraviolet irradiation sub-module, a second ultraviolet irradiation sub-module, a third ultraviolet irradiation sub-module, and a fourth ultraviolet irradiation sub-module; The displacement measurement module is used to measure the displacement of the test mass relative to the parallel plates in the horizontal direction, convert the displacement into a voltage signal and transmit it to the charge measurement module; The charge measurement module is used to receive the voltage signal, calculate the charge value of the test mass according to the voltage signal and input it to the disturbance observer sliding mode control module; At the same time, the calculated charge value of the test mass and the set charge value are subtracted to obtain a charge error signal and input to the disturbance observer sliding mode control module; The disturbance observer sliding mode control module is used to receive the charge value of the test mass, the set charge value, and the charge error signal, and calculate the charge and discharge rate required to control the charge of the test mass to the set charge value based on the charge on-orbit charge and discharge model and input it to the charge actuator module; The charge actuator module is used to receive the charge and discharge rate, drive the ultraviolet light irradiation module to irradiate the parallel plates in the vertical direction or the surface of the test mass, and apply bias voltages with the same magnitude and opposite directions to the parallel plates on both sides in the vertical direction respectively, so as to control the charge of the test mass to the set charge value.

3. The charge management device based on disturbance observer sliding mode control according to claim 2, characterized in that, The number of the parallel plates is 6, including 4 parallel plates in the horizontal direction and 2 parallel plates in the vertical direction; The four horizontally parallel plates are respectively a first parallel plate, a second parallel plate, a third parallel plate, and a fourth parallel plate; the first parallel plate and the third parallel plate are located on one side of the test mass in the horizontal direction, and the second parallel plate and the fourth parallel plate are located on the other side of the test mass in the horizontal direction; the first parallel plate and the second parallel plate are parallel and facing each other; the third parallel plate and the fourth parallel plate are parallel and facing each other. The two vertically parallel plates are respectively a fifth parallel plate and a sixth parallel plate; the fifth parallel plate is located on one side of the test mass in the vertical direction, and the sixth parallel plate is located on the other side of the test mass in the vertical direction; the fifth parallel plate and the sixth parallel plate are parallel and facing each other.

4. The charge management device based on disturbance observer sliding mode control according to claim 2, characterized in that, The driving ultraviolet light irradiation module irradiates the vertically parallel plates or the surface of the test mass, specifically: Drive the first ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the vertically parallel plate on one side, drive the second ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the surface of the test mass opposite to the vertically parallel plate on one side, drive the third ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the vertically parallel plate on the other side, and drive the fourth ultraviolet irradiation sub-module to emit ultraviolet light to irradiate the surface of the test mass opposite to the vertically parallel plate on the other side.

5. A charge management method based on disturbance observer sliding mode control, characterized in that, The method uses the device described in any one of claims 1-4, and includes the following steps: Place parallel plates in the horizontal and vertical directions of the test mass respectively. Among them, all parallel plates are parallel to the test mass and have the same distance. The number of parallel plates placed on both sides of the test mass in the horizontal direction is the same, and the number of parallel plates placed on both sides of the test mass in the vertical direction is the same. Apply AC driving voltages with the same magnitude and opposite directions to the parallel plates in the horizontal direction of the test mass, drive the test mass to rotate, measure the displacement of the test mass relative to the parallel plates in the horizontal direction through the displacement measurement module, and convert this displacement into a voltage signal and transmit it to the charge measurement module. The charge measurement module calculates the charge value of the test mass from the voltage signal and inputs it to the disturbance observer sliding mode control module. At the same time, the difference between the calculated charge value of the test mass and the set charge value is used as the charge error signal and input to the disturbance observer sliding mode control module. The disturbance observer sliding mode control module receives the charge value of the test mass, the set charge value, and the charge error signal, and based on the charge on-orbit charge and discharge model, calculates the charge and discharge rate required to control the charge of the test mass to the set charge value and inputs it to the charge actuator module. The charge actuator module receives the charge and discharge rate, drives the ultraviolet light irradiation module to irradiate the vertically parallel plates or the surface of the test mass, and applies bias voltages with the same magnitude and opposite directions to the parallel plates on both sides in the vertical direction respectively, so as to control the charge of the test mass to the set charge value.

6. A charge management method based on disturbance observer sliding mode control according to claim 5, characterized in that The in-orbit charge charging and discharging model is , where represents the attenuation coefficient of the actual charging rate of the test mass in space; is the charge value of the test mass; is the derivative of the charge value of the test mass; represents the charging and discharging rate output by the sliding mode control module; represents the attenuation coefficient of the ultraviolet light charging and discharging rate of the actual model; represents the unknown disturbance from the outside; The charge and discharge rate output by the sliding mode control module is , where represents the charge error signal, represents the sign function, represents the first gain coefficient of the sliding mode control module, represents the second gain coefficient of the sliding mode control module, represents the sliding mode surface switching function; the sliding mode surface switching function is , where represents the gain coefficient; The output of the disturbance observer is ; Among them, represents the estimation of the external unknown disturbance , represents the derivative of the estimation of the external unknown disturbance, represents the estimation of the charge value of the test mass, is the derivative of the estimation of the charge value of the test mass, represents the charge and discharge rate output by the disturbance observation control module in the disturbance observation sliding mode control module, represents the first gain coefficient of the disturbance observer, represents the second gain coefficient of the disturbance observer; The charge and discharge rate output by the interference observation control module is .

7. A charge management device based on disturbance observer sliding mode control, characterized in that, It includes one or more processors for implementing the charge management method based on disturbance observer sliding mode control described in any one of claims 5-6.

8. A computer-readable storage medium having a program stored thereon, characterized in that, When executed by a processor, the program is used to implement the charge management method based on disturbance observer sliding mode control described in any one of claims 5-6.

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