CN115167593A - High-precision constant current source for three-dimensional magnetic compensation of SERF gyroscope - Google Patents
High-precision constant current source for three-dimensional magnetic compensation of SERF gyroscope Download PDFInfo
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Abstract
The invention relates to a high-precision constant current source for three-dimensional magnetic compensation of an SERF gyroscope, which comprises: host computer and constant current source output control circuit, constant current source output control circuit includes: the device comprises a serial port communication control module, a microcontroller module, a reference voltage source module, a V/I conversion module and a load coil. The invention can obtain higher-precision current control.
Description
Technical Field
The invention belongs to the technical field of electronic circuits, and relates to a high-precision programmable constant current source, in particular to a high-precision constant current source for three-dimensional magnetic compensation of an SERF gyroscope.
Background
The control of atomic spin in an SERF state is a precondition for realizing an ultrahigh-precision atomic spin gyroscope; and the weak magnetic field environmental condition is a necessary condition for realizing the atomic spin SERF state. The environmental magnetic field directly affects the output of the gyroscope, so active and passive magnetic shielding technologies are needed, and the environmental remanence is reduced as much as possible. Due to the presence of geomagnetism, high performance multi-layer magnetic shielding is required. However, the shielding barrel is provided with a light through hole which influences the shielding performance and the shielding barrel has residual magnetism, so that active three-dimensional magnetic field compensation is needed on the basis of passive magnetic shielding for better realizing the SERF gyroscope, and the environmental magnetic field is further reduced. The stability of the three-dimensional compensation magnetic field is also one of factors determining the zero offset drift of the gyroscope, the three-dimensional compensation magnetic field is realized by introducing weak current into a three-dimensional magnetic field coil, and the stability of current output directly determines the effects of three-dimensional magnetic compensation and reduction of environmental remanence. Therefore, the design of the high-precision constant current source for the three-dimensional magnetic compensation of the SERF gyroscope has great significance.
Firstly, in the experimental process of constructing an SERF principle prototype, the current introduced into the three-dimensional magnetic field coil needs to have higher precision and stability so as to meet the requirement of experimental weak magnetic compensation; the working environment of the SERF atomic gas chamber is sensitive to the temperature, so that electronic devices with small heat generation and good thermal stability need to be adopted as far as possible; in order to facilitate the overall control of the SERF prototype system, the output current is displayed and controlled by Labview upper computer software through a serial port communication control module, and the current source output current can be set and displayed through a software interface.
The current source circuit has the main limitations that:
a reference voltage source built by an analog device is easily influenced by the environment, so that the output current is unstable; the V/I conversion circuit built by the triode can cause temperature rise after long-term operation, and the temperature of the working environment of the atomic gas chamber is influenced; the current regulation function is usually realized by changing the voltage by using a potentiometer, and has no software control and man-machine interaction functions.
Upon search, no prior art publications that are identical or similar to the present invention were found.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a high-precision constant current source for three-dimensional magnetic compensation of an SERF gyroscope, which has the advantages of reasonable design, high stability, small heat generation and controllable upper computer.
The invention solves the practical problem by adopting the following technical scheme:
a high precision constant current source for three dimensional magnetic compensation of a SERF gyroscope, comprising: host computer and constant current source output control circuit, constant current source output control circuit includes: the device comprises a serial port communication control module, a microcontroller module, a reference voltage source module, a V/I conversion module and a load coil; the upper computer sends a control instruction to the constant current source output control circuit by using the serial port communication control module; the serial port communication control module is connected with the microcontroller module and is used for carrying out serial port communication with the microcontroller and sending a control instruction to the microcontroller; the microcontroller module is connected with the input end of the reference voltage source module and is used for carrying out program-controlled regulation on the output voltage of the reference voltage source; the reference voltage source module is used for outputting constant voltage, the output voltage of the reference voltage source can be adjusted under the action of the microcontroller module, and the output end of the reference voltage source module is connected with the V/I conversion module; the V/I conversion module is used for converting constant voltage output by the reference voltage source into constant current output through the conversion circuit, the output end of the V/I conversion module is connected with the load coil, and the load coil obtains a corresponding compensation magnetic field by outputting current with a certain value.
Moreover, the V/I conversion module is a dual V/I conversion circuit built by dual integrated operational amplifiers, and includes: reference voltage input V REF Four constant value resistors R1, R2, R3 and R4, and a sampling resistor R ref An operational amplifier U1 and an operational amplifier U2; the operational amplifier U1 forms an adder, and the operational amplifier U2 forms a follower; reference voltage input V ref The input end of the constant value resistor R1 is connected with a constant value resistor R1, and the constant value resistor R1 is respectively connected with the input anode of the operational amplifier U1 and a constant value resistor R2; the other end of the constant value resistor R2 is connected with the input cathode and the output end of the operational amplifier U2 respectively to form a follower; the input cathode of the operational amplifier U1 is respectively connected with the constant value resistors R3 and R4, the other end of the R3 is grounded, and the other end of the R4 is connected with the output end of the U1; the U1 output end is also connected with a sampling resistor R ref Connected, sampling resistor R ref The other end is connected with the current output positive end I 0 + connected, current output negative terminal I 0 -ground, load coil connected to positive output terminal I 0 + and current outputNegative terminal I 0 -in the middle.
Moreover, the three-dimensional magnetic field coils of the SERF gyroscope comprise four axial coils and two pairs of radial coils; the axial coil is a coaxial coil, and the radial coil is a saddle-shaped coil; the two pairs of radial coils are arranged oppositely and surround the outer sides of the four axial coils; the four axial coils and the two pairs of radial coils are wound on an integral cylindrical coil framework.
Moreover, the output end of the upper computer is connected with the USB-to-serial port device through a USB interface; the USB serial port conversion device comprises a level sampling interface RXD + and an RXD-of the USB serial port conversion device, and a level transmitting interface TXD + and a level transmitting interface TXD-of the serial port communication control module respectively; level transmitting interfaces TXD + and TXD-of the USB serial-to-serial device are respectively connected with a level sampling interface RXD + and RXD-of the serial communication control module; the instruction received by the serial port communication control module is transmitted to the microcontroller module through an I/O port of the microcontroller module; the USB-to-serial port equipment is connected to the upper computer through a USB interface.
The invention has the advantages and beneficial effects that:
1. the invention provides a high-precision constant current source for three-dimensional magnetic compensation of an SERF gyroscope, which comprises: a reference voltage source module for outputting a constant voltage; the reference voltage source is changed into a V/I conversion module for current source output through a conversion circuit, and the V/I conversion module is a double V/I conversion circuit built by double integrated operational amplifiers; and the microcontroller module changes the reference voltage source so as to change the output current. The reference voltage source signal is given by a high-precision digital-to-analog converter with controllable program, and the output voltage of the reference voltage source can be controlled by an upper computer serial port communication control algorithm, so that the current output is adjustable; compared with the control of a microcontroller, the Labview upper computer serial port communication control has the advantages of higher digits, decimal fraction retention and the like, so that the current control with higher precision is obtained.
2. The reference voltage source built by the high-precision digital-to-analog converter has the characteristics of program control and strong anti-interference capability.
3. According to the invention, the loop current of the double V/I conversion circuit built by the double integrated operational amplifiers is small, the heating is low, the stability of current output can be improved, and the influence of temperature change on the atomic gas chamber is reduced.
4. The constant current source circuit designed by the invention has a serial port communication function, can realize the adjustment control of the on-off and the size of the current by the software of an upper computer, and is more favorable for the man-machine interaction.
Drawings
FIG. 1 is a schematic diagram of a SERF gyroscopic principle prototype three-dimensional magnetic field coil of the present invention;
FIG. 2 is a functional block diagram of the high precision constant current source circuit of the present invention;
FIG. 3 is a schematic diagram of a V/I conversion circuit built by a double integrated operational amplifier of the high-precision constant current source circuit;
FIG. 4 is a block diagram of a schematic implementation of the current regulation of the high precision constant current source of the present invention;
description of reference numerals:
1-axial coil (Barker); 2-radial coil (saddle shape).
Detailed Description
The embodiments of the invention will be described in further detail below with reference to the accompanying drawings:
a high-precision constant current source for three-dimensional magnetic compensation of a SERF gyroscope comprises: host computer and constant current source output control circuit, constant current source output control circuit includes: the device comprises a serial port communication control module, a microcontroller module, a reference voltage source module, a V/I conversion module and a load coil;
the upper computer sends a control instruction to the constant current source output control circuit by using the serial port communication control module; the serial port communication control module is connected with the microcontroller module and is used for carrying out serial port communication with the microcontroller and sending a control instruction to the microcontroller; the microcontroller module is connected with the input end of the reference voltage source module and is used for carrying out program-controlled regulation on the output voltage of the reference voltage source; the reference voltage source module is used for outputting constant voltage, the output voltage of the reference voltage source can be adjusted under the action of the microcontroller module, and the output end of the reference voltage source module is connected with the V/I conversion module; the V/I conversion module is used for converting constant voltage output by the reference voltage source into constant current output through the conversion circuit, the output end of the V/I conversion module is connected with the load coil, and the load coil obtains a corresponding compensation magnetic field by outputting current with a certain value;
in this embodiment, the V/I conversion module is a dual V/I conversion circuit built by dual integrated operational amplifiers, and includes: reference voltage input V REF Four constant value resistors R1, R2, R3 and R4, and a sampling resistor R ref An operational amplifier U1 and an operational amplifier U2; the operational amplifier U1 forms an adder, and the operational amplifier U2 forms a follower; reference voltage input V ref The input end of the constant value resistor R1 is connected with a constant value resistor R1, and the constant value resistor R1 is respectively connected with the input anode of the operational amplifier U1 and a constant value resistor R2; the other end of the constant value resistor R2 is connected with the input cathode and the output end of the operational amplifier U2 respectively to form a follower; the input cathode of the operational amplifier U1 is respectively connected with the constant value resistors R3 and R4, the other end of the R3 is grounded, and the other end of the R4 is connected with the output end of the U1; the U1 output end is also connected with a sampling resistor R ref Connected, sampling resistor R ref The other end is connected with the current output positive end I 0 + connected, current output negative terminal I 0 Ground, the load coil being connected to the positive output terminal I 0 + and a negative terminal I for current output 0 -in the middle.
In this embodiment, the three-dimensional magnetic field coils of the SERF gyroscope include four axial coils and two pairs of radial coils; the axial coil is a coaxial coil, and the radial coil is a saddle coil; the two pairs of radial coils are arranged oppositely and surround the outer sides of the four axial coils; the four axial coils and the two pairs of radial coils are wound on an integral cylindrical coil framework.
In this embodiment, the output end of the upper computer is connected with the USB to serial port device through a USB interface; the USB serial port conversion device comprises a level sampling interface RXD + and an RXD-of the USB serial port conversion device, and a level transmitting interface TXD + and a level transmitting interface TXD-of the serial port communication control module respectively; level transmitting interfaces TXD + and TXD-of the USB serial-to-serial device are respectively connected with a level sampling interface RXD + and RXD-of the serial communication control module; the instruction received by the serial port communication control module is transmitted to the microcontroller module through an I/O port of the microcontroller module; the USB-to-serial port equipment is connected to the upper computer through a USB interface.
In this embodiment, the serial communication control process is implemented by communicating with a serial communication control module through a USB to serial device, such as a USB serial line or a moxa box. Common communication standards include RS232, RS422, RS485, and the like. The invention adopts RS422 serial port communication mode, which is a data transmission protocol adopting four-wire, full duplex, differential transmission and multipoint communication, and the four-wire interface is defined as follows: TXD-, RXD-, TXD + and RXD +. The serial port communication control module comprises a level sampling interface and a level sending interface, and the specific communication mode is as follows: level sampling interfaces RXD + and RXD-of the USB serial-to-serial device are respectively connected with a level transmitting interface TXD + and TXD-of the serial communication control module; level transmitting interfaces TXD + and TXD-of the USB serial-to-serial device are respectively connected with a level sampling interface RXD + and RXD-of the serial communication control module; the instruction received by the serial port communication control module is transmitted to the microcontroller through an I/O port of the microcontroller module; the USB-to-serial port equipment is connected to the upper computer through a USB interface.
Fig. 1 is a schematic diagram of a SERF gyroscope three-dimensional magnetic field coil. It comprises four axial coils 1, two pairs of radial coils (only one direction of the radial saddle coil is shown in the figure for ease of viewing) 2. Coaxial coils such as Helmholtz coils, barker four coils are commonly used for axial coils. The radial coil generally adopts conventional Helmholtz coil, but the coil part is more dispersed, the equipment is inconvenient, and the magnetic field is difficult even in the cylinder magnetic shield device, therefore adopts saddle-shaped coil to replace, can coil on an integral cylindrical coil skeleton, has avoided the loaded down with trivial details shortcoming of above-mentioned equipment, has just also realized that a coil skeleton can coil all three-dimensional coils.
Fig. 2 is a functional block diagram of a high-precision constant current source design principle. The device comprises a serial port communication control part, a microcontroller part, a reference voltage source part, a V/I conversion part, a load coil and the like.
FIG. 3 is a schematic diagram of a V/I conversion circuit with a high-precision constant current source built by an integrated operational amplifier. In the figure V REF Is a reference voltage, R ref Is a sampling resistor. The 4 resistors in the box of the figure are identical in value. Because the temperature has less influence on the parameters of the integrated operational amplifier than the parameters of the transistor and the field effect transistor, the constant current source formed by the integrated operational amplifier has the advantages of better stability and higher constant current performance. The grounding device is widely applied to occasions where one end of a load needs to be grounded. The operational amplifier U1 forms an adder, the U2 forms a follower, and the U1 and the U2 both use low-noise, low-offset and high-open-loop gain bipolar operational amplifier chips.
Under ideal conditions, according to the virtual short and virtual break principle of the operational amplifier, the output current can be obtained:
I O ＝V REF /R ref
in the formula:
V REF -inputting a reference voltage (V);
R ref -a sampling resistance (Ω).
From the formula, when V REF And R ref When the value of (A) is not changed, I o The output can be constant and is independent of the value of the load (within the linear working area of the operational amplifier). The current magnitude can be changed by changing the input reference V REF Or adjusting the reference resistance R ref Is realized, stable small current and compensation calibration are easily obtained. In the present invention, the use of a change V REF And inputting a reference standard to realize current size adjustment.
The dual operational amplifier constant current source has two significant advantages: 1. the load may be grounded; 2. the output current may be a bi-directional output or an alternating current output (usually on the premise of dual power supply).
Fig. 4 is a block diagram of a schematic implementation of the current regulation of a high-precision constant current source. The specific working process is as follows: the method comprises the steps that digital voltage data information to be sent is obtained through a serial port of an upper computer, the data to be sent is converted into an encoded data stream which accords with a serial port communication protocol and a baud rate, and the encoded data stream is downloaded to a USB-to-serial port device; the serial port Rx level sampling interface receives the coded data and sends the coded data to the microcontroller for processing operation, and the processed and operated data can be used as a level control word of the digital-to-analog converter, so that V is changed REF Inputting a reference voltageAnd current size adjustment is realized.
It should be emphasized that the examples described herein are illustrative and not restrictive, and thus the present invention includes, but is not limited to, those examples described in this detailed description, as well as other embodiments that can be derived from the teachings of the present invention by those skilled in the art and that are within the scope of the present invention.
Claims (4)
1. A high-precision constant current source for three-dimensional magnetic compensation of an SERF gyroscope is characterized in that: the method comprises the following steps: host computer and constant current source output control circuit, constant current source output control circuit includes: the device comprises a serial port communication control module, a microcontroller module, a reference voltage source module, a V/I conversion module and a load coil; the upper computer sends a control instruction to the constant current source output control circuit by using the serial port communication control module; the serial port communication control module is connected with the microcontroller module and is used for carrying out serial port communication with the microcontroller and sending a control instruction to the microcontroller; the microcontroller module is connected with the input end of the reference voltage source module and is used for carrying out program-controlled regulation on the output voltage of the reference voltage source; the reference voltage source module is used for outputting constant voltage, the output voltage of the reference voltage source can be adjusted under the action of the microcontroller module, and the output end of the reference voltage source module is connected with the V/I conversion module; the V/I conversion module is used for converting constant voltage output by the reference voltage source into constant current output through the conversion circuit, the output end of the V/I conversion module is connected with the load coil, and the load coil obtains a corresponding compensation magnetic field by outputting current with a certain value.
2. The high-precision constant current source for three-dimensional magnetic compensation of the SERF gyroscope of claim 1, wherein: the V/I conversion module is a double V/I conversion circuit built by double integrated operational amplifiers, and comprises: reference voltage input V REF Four constant value resistors R1, R2, R3 and R4, and a sampling resistor R ref An operational amplifier U1 and an operational amplifier U2; the operational amplifier U1 forms an adder, and the operational amplifier U2 forms a follower; reference voltage input V ref The input end of the constant value resistor R1 is connected with a constant value resistor R1, and the constant value resistor R1 is respectively connected with an operational amplifier U1The input anode is connected with a constant value resistor R2; the other end of the constant value resistor R2 is connected with the input cathode and the output end of the operational amplifier U2 respectively to form a follower; the input cathode of the operational amplifier U1 is respectively connected with the constant value resistors R3 and R4, the other end of the R3 is grounded, and the other end of the R4 is connected with the output end of the U1; the U1 output end is also connected with a sampling resistor R ref Connected, sampling resistor R ref The other end is connected with the current output positive end I 0 + connected, current output negative terminal I 0 Ground, the load coil being connected to the positive output terminal I 0 + and a negative terminal I for current output 0 -in the middle.
3. The high-precision constant current source for three-dimensional magnetic compensation of the SERF gyroscope of claim 1, wherein: the three-dimensional magnetic field coils of the SERF gyroscope comprise four axial coils and two pairs of radial coils; the axial coil is a coaxial coil, and the radial coil is a saddle coil; the two pairs of radial coils are arranged in an opposite way and surround the outer sides of the four axial coils; the four axial coils and the two pairs of radial coils are wound on an integral cylindrical coil framework.
4. The high-precision constant current source for three-dimensional magnetic compensation of the SERF gyroscope of claim 1, wherein: the output end of the upper computer is connected with the USB-to-serial port device through a USB interface; the USB serial port conversion device comprises a level sampling interface RXD + and an RXD-of the USB serial port conversion device, and a level transmitting interface TXD + and a level transmitting interface TXD-of the serial port communication control module respectively; level transmitting interfaces TXD + and TXD-of the USB serial-to-serial device are respectively connected with a level sampling interface RXD + and RXD-of the serial communication control module; the instruction received by the serial port communication control module is transmitted to the microcontroller module through an I/O port of the microcontroller module; the USB-to-serial port equipment is connected to the upper computer through a USB interface.
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| CN106773893A (en) * | 2016-11-11 | 2017-05-31 | 东南大学 | The program controlled constant current source circuit of the device for force feedback based on magnetic flow liquid |
| CN108490823A (en) * | 2018-03-02 | 2018-09-04 | 北京航空航天大学 | High-precision field drives stored program controlled |
| CN113433999A (en) * | 2021-07-12 | 2021-09-24 | 北京航空航天大学 | High-precision low-noise program-controlled current source for magnetic field generation |
| CN114001724A (en) * | 2021-11-19 | 2022-02-01 | 中国船舶重工集团公司第七0七研究所 | Method for three-dimensional orthogonal coincidence of optical path and magnetic field of SERF (spin-exchange nuclear spin gyroscope) |
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2022
- 2022-06-30 CN CN202210762612.9A patent/CN115167593A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106773893A (en) * | 2016-11-11 | 2017-05-31 | 东南大学 | The program controlled constant current source circuit of the device for force feedback based on magnetic flow liquid |
| CN108490823A (en) * | 2018-03-02 | 2018-09-04 | 北京航空航天大学 | High-precision field drives stored program controlled |
| CN113433999A (en) * | 2021-07-12 | 2021-09-24 | 北京航空航天大学 | High-precision low-noise program-controlled current source for magnetic field generation |
| CN114001724A (en) * | 2021-11-19 | 2022-02-01 | 中国船舶重工集团公司第七0七研究所 | Method for three-dimensional orthogonal coincidence of optical path and magnetic field of SERF (spin-exchange nuclear spin gyroscope) |
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