Active magnetic compensation bipolar current source driving system

Abstract

The invention relates to the technical field of active magnetic compensation current driving, in particular to an active magnetic compensation bipolar current source driving system which comprises a preceding-stage filtering and protection module, a DC-DC switching power supply module, an LDO voltage stabilization module, an analog compensation network module, a bipolar output voltage-controlled current source module, a microcontroller module, a current setting module and a digital acquisition module. The primary power supply is used as the input of the DC-DC switching power supply module after being subjected to pre-filtering and protection, and the multi-path LDO voltage stabilizing module is used for stabilizing the voltage of the output of the DC-DC power supply, reducing the ripple noise of a switch and supplying power to the bipolar voltage-controlled current source module. The microcontroller module communicates with the current setting and data acquisition module in an SP I mode, and real-time current setting and reading are achieved. The active magnetic compensation electric control system is low in cost and noise, stable bipolar current output can be provided for the magnetic compensation coil, and the active magnetic compensation electric control system has the advantages of being low in noise, high in stability, rapid in response and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of active magnetic compensation current drive technology, and in particular to an active magnetic compensation bipolar current source drive system. Background Art

[0002] Fluctuations in the Earth's magnetic field can significantly impact the results of quantum precision science experiments conducted in extremely weak magnetic field environments. Therefore, suppressing geomagnetic interference is crucial for improving the accuracy and reliability of related experiments. Active magnetic compensation, as a key method for suppressing geomagnetic interference, offers the significant advantages of high precision and full-band suppression. The bipolar current drive in active magnetic compensation devices supplies current to the coils, making the current noise level and current response speed crucial, directly impacting residual magnetic field indicators and magnetic field stability.

[0003] Current active magnetic compensation bipolar circuit drivers suffer from insufficient dynamic current response due to the coil's inductive nature, making them unable to track rapidly changing active magnetic compensation signals in real time. This results in magnetic field lag and high current noise at high power output, which can couple into the coil and introduce magnetic field noise. Therefore, a high-precision, low-noise bipolar current source with multi-channel coordinated output and microsecond-level transient response is needed to meet the core requirements of active magnetic field compensation. Summary of the Invention

[0004] In view of this, the present invention addresses the deficiencies of the prior art and proposes an active magnetically compensated bipolar current source drive system, aiming to solve at least one of the problems raised in the above background technology.

[0005] The present invention provides an active magnetically compensated bipolar current source drive system, comprising: a pre-stage filtering and protection module, a DC-DC switching power supply module, an LDO voltage regulator module, an analog compensation network module, a bipolar output voltage-controlled current source module, a microcontroller module, a current setting module, and a digital acquisition module, wherein:

[0006] The pre-stage filtering and protection module is configured to perform EMI filtering on the input primary power supply, reduce differential mode and common mode interference through X / Y capacitors, and protect the post-stage circuit with a surge suppressor;

[0007] The DC-DC switching power supply module is configured to perform power conversion on the voltage after the pre-stage filtering;

[0008] The LDO voltage regulator module is configured to perform low voltage difference regulation on the output voltage of the DC-DC switching power supply module, provide Vdd and Vss voltages for the front stage of the bipolar output voltage-controlled current source module, reduce switching ripple noise, and provide the power supply voltage required by the current setting module and the digital acquisition module;

[0009] The current setting module is used to set the current output size of the bipolar output voltage-controlled current source module;

[0010] The microcontroller module is configured to control the DAC via the SPI bus and perform digital settings;

[0011] The bipolar output voltage-controlled current source module is composed of an operational amplifier, an instrumentation amplifier, a sampling resistor, and a power amplifier. The front-stage Vdd and Vss are set near the maximum power consumption critical point of the power amplifier to increase the bandwidth of the output current.

[0012] The analog compensation network module is configured to perform error amplification and loop compensation on the control voltage output by the current setting module and the output voltage of the instrumentation amplifier;

[0013] The digital acquisition module is configured to monitor the system output current and communicate with the microcontroller module via SPI to upload current data in real time;

[0014] The microcontroller module is used to drive the system output current setting and output current data collection.

[0015] In some embodiments, the pre-stage filtering and protection module is composed of a fuse, a TVS diode, a differential mode capacitor, a common mode inductor, a Y capacitor, an EMI filter and a surge suppressor.

[0016] In some embodiments, the DC-DC switching power supply module includes:

[0017] A first integrated switch driver chip, a second integrated switch driver chip and peripheral circuits thereof;

[0018] The first integrated switch driver chip has a 32V input voltage, an input filter capacitor is connected between the input and ground, the SW pin of the integrated switch driver chip is connected to the first end of the output inductor, the second end of the output inductor is connected to the output voltage for step-down, and the FB pin is connected to a voltage divider resistor network for desired output voltage conversion;

[0019] The second integrated switch driver chip has a 32V input voltage for voltage polarity reversal, and its input is connected to the first end of the coupled inductor L1; the first switch transistor S1 is connected to the second end of the coupled inductor L1; the first end of the jumper capacitor C1 is connected to the common node of the coupled inductor L1 and the first switch transistor S1, the second end of the jumper capacitor C1 is connected to the first end of the coupled inductor L2, and the second end of the coupled inductor L2 is connected to the output voltage; the first end of the second switch transistor S2 is connected to the first end of the coupled inductor L2, and the second end of the second switch transistor S2 is connected to ground;

[0020] An output filter capacitor C2 is connected in parallel between the output voltage terminal and the ground;

[0021] The cross-capacitor C1 is configured to transfer energy bidirectionally from input to output by alternately charging and discharging;

[0022] The sampling resistor Rs is configured to sample the current flowing through the first switch tube S1 and is connected to the SENSE pin to control the peak current.

[0023] In some embodiments, the LDO voltage regulator module is configured to perform low voltage difference regulation on the output voltages Vdd and Vss of the DC-DC switching power supply module to supply power to the subsequent bipolar output voltage-controlled current source module.

[0024] In some embodiments, the current setting module uses a 16-bit analog-to-digital conversion chip DAC8734, an external reference input 5V reference voltage, and simultaneously outputs a four-channel, ±10V bipolar voltage. The current setting module is connected to the microcontroller module via an SPI communication bus.

[0025] In some embodiments, the input end of the voltage follower circuit of the bipolar output voltage-controlled current source module is connected to the output end of the current setting module, and the output end of the bipolar output voltage-controlled current source module is connected to the input end of the inverting proportional circuit;

[0026] The operational amplifier is used to amplify the error between the input voltage signal and the output current signal;

[0027] The power amplifier is used to output bipolar power current;

[0028] The instrument amplifier is used to convert the current signal on the sampling resistor into a voltage signal;

[0029] The sampling resistor is used to sample the output current signal and convert it into a voltage signal to transmit to the digital acquisition module.

[0030] In some embodiments, the analog compensation network module is used to perform loop compensation on the error-amplified signal.

[0031] In some embodiments, the digital acquisition module uses a multi-channel high-precision digital-to-analog conversion chip AD7689, one acquisition channel is connected to the output voltage signal of the current setting module, and the other acquisition channel acquires the current sampling signal of the bipolar output voltage-controlled current source module;

[0032] The digital acquisition module is connected to the microcontroller module via the SPI bus, and transmits the acquired two-way voltage digital signals for current state monitoring.

[0033] In some embodiments, the microcontroller module communicates with the current setting module and the digital acquisition module via SPI to set the current and read the actual current value.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] A DC-DC switching power supply is used to step down the input voltage and reverse its polarity, achieving a voltage conversion efficiency exceeding 90% for step-down conversion and over 80% for polarity conversion. Multiple LDO circuits are used to provide low-dropout voltage regulation on the two outputs of the DC-DC switching power supply module, reducing switching ripple noise. After voltage regulation, the high-power input voltage of the positive and negative bipolar current source power amplifier is at its critical operating point, reducing power consumption in the current source circuit and providing low-noise, high-current drive for the active magnetic compensation device.

[0036] The output current range of the current drive system of the present invention is -500 to 500 mA, and the noise is less than 200 nA and the current fluctuation is less than 28 μA under a current load of 500 mA. The closed-loop bandwidth of the current source system is 38 kHz.

[0037] The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure.

[0038] Other features and aspects of the present disclosure will become more apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0040] Figure 1 A control block diagram of an active magnetically compensated bipolar current source drive system according to an embodiment of the present invention;

[0041] Figure 2 A schematic diagram of a polarity conversion circuit for a DC-DC switching power supply module in an active magnetically compensated bipolar current source drive system according to an embodiment of the present invention;

[0042] Figure 3 A schematic diagram of a step-down conversion circuit of a DC-DC switching power supply module in an active magnetically compensated bipolar current source drive system according to an embodiment of the present invention;

[0043] Figure 4A control block diagram of a bipolar output voltage-controlled current source module of an active magnetically compensated bipolar current source drive system provided by an embodiment of the present invention;

[0044] Figure 5 This is a circuit principle block diagram of the analog compensation network module of the active magnetic compensation bipolar current source drive system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0046] In the description of this application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0047] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout this application, unless otherwise specified, "plurality" means two or more.

[0048] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0049] See Figure 1-5 As shown, an active magnetically compensated bipolar current source driving system according to an embodiment of the present application includes:

[0050] Pre-stage filtering and protection module, DC-DC switching power supply module, LDO voltage regulator module, analog compensation network module, bipolar output voltage-controlled current source module, microcontroller module, current setting module, digital acquisition module, including:

[0051] The pre-stage filtering and protection module is configured to perform EMI filtering on the input primary power supply, reduce differential mode and common mode interference through X / Y capacitors, and use surge suppressors to protect the subsequent circuits from surge current / voltage impacts;

[0052] The DC-DC switching power supply module is configured to perform power conversion on the voltage after the pre-stage filtering, and obtain the low-noise, high-efficiency voltage required by the post-stage circuit after polarity and magnitude conversion based on the integrated switching power supply chip;

[0053] The LDO voltage regulator module is configured to perform low voltage difference regulation on the output voltage of the DC-DC switching power supply module, provide Vdd and Vss voltages for the front stage of the bipolar output voltage-controlled current source module, reduce switching ripple noise, and provide the power supply voltage required by the current setting module and the digital acquisition module;

[0054] The current setting module is used to set the current output size of the bipolar output voltage-controlled current source module;

[0055] The microcontroller module is configured to control the DAC via the SPI bus and perform digital settings;

[0056] The bipolar output voltage-controlled current source module is composed of an operational amplifier, an instrumentation amplifier, a sampling resistor, and a power amplifier to achieve bipolar current output. The front-stage Vdd and Vss are set near the maximum power consumption critical point of the power amplifier to increase the bandwidth of the output current and provide an output current range of -500 to +500 mA for the active magnetic compensation coil.

[0057] The analog compensation network module is configured to perform error amplification and loop compensation on the control voltage output by the current setting module and the output voltage of the instrumentation amplifier, so as to improve the stability and speed of the current source loop;

[0058] The digital acquisition module is configured to monitor the system output current and communicate with the microcontroller module via SPI to upload current data in real time;

[0059] The microcontroller module is used to drive the system output current setting and output current data collection.

[0060] It should be understood that if Figure 4As shown in the figure, the low-noise AD8674 operational amplifier serves as the error amplifier in the analog compensation network. The power amplifier circuit uses the OPA544 power amplifier, configured with a gain of 2 (R1 / R2 = 1). The instrumentation amplifier uses the high-precision INA849, configured with a gain of 200. The current output terminal samples the load current in real time and converts it into a voltage signal, which is then conditioned by a high-precision instrumentation amplifier. The amplified feedback voltage Vf and the control voltage Vc generated by the current setting module are combined in the analog compensation network module for error amplification and loop compensation. This dynamically adjusts the power circuit output, ensuring that the load current accurately tracks the preset command value. This closed-loop negative feedback control mechanism improves system response speed while effectively suppressing the effects of temperature drift and nonlinear distortion on output accuracy.

[0061] In some specific embodiments, the pre-stage filtering and protection module is composed of a fuse, a TVS diode, a differential mode capacitor, a common mode inductor, a Y capacitor, an EMI filter and a surge suppressor.

[0062] like Figure 2 As shown, in some specific embodiments, the DC-DC switching power supply module includes:

[0063] A first integrated switch driver chip, a second integrated switch driver chip and peripheral circuits thereof;

[0064] The first integrated switch driver chip has a 32V input voltage, an input filter capacitor is connected between the input and ground, the SW pin of the integrated switch driver chip is connected to the first end of the output inductor, the second end of the output inductor is connected to the output voltage for step-down, and the FB pin is connected to a voltage divider resistor network for desired output voltage conversion;

[0065] The second integrated switch driver chip has a 32V input voltage for voltage polarity reversal, and its input is connected to the first end of the coupled inductor L1; the first switch transistor S1 is connected to the second end of the coupled inductor L1; the first end of the jumper capacitor C1 is connected to the common node of the coupled inductor L1 and the first switch transistor S1, the second end of the jumper capacitor C1 is connected to the first end of the coupled inductor L2, and the second end of the coupled inductor L2 is connected to the output voltage; the first end of the second switch transistor S2 is connected to the first end of the coupled inductor L2, and the second end of the second switch transistor S2 is connected to ground;

[0066] An output filter capacitor C2 is connected in parallel between the output voltage terminal and the ground;

[0067] The cross-capacitor C1 is configured to transfer energy from input to output in a bidirectional manner by alternately charging and discharging, so that the polarity of the input voltage and the output voltage are opposite;

[0068] The sampling resistor Rs is configured to sample the current flowing through the first switch tube S1 and is connected to the SENSE pin to control the peak current.

[0069] It should be understood that the Vss voltage obtained by polarity reversal of the DC-DC switching power supply is obtained by designing the integrated switch driver chip LT3758 of the Cuk topology structure. It is configured in discontinuous conduction mode under low load and enters continuous conduction mode when the current output is above 500mA. Dual switch tubes and coupled inductors are set externally; the integrated switch driver chip LT3758 inputs a 32V voltage, and its input is connected to the first end of the coupled inductor L1; the drain of the first switch tube S1 is connected to the second end of the coupled inductor L1, the source is connected to the SENSE pin, and the gate is connected to the SW pin for controlling the conduction and shutdown of the switch tube; A first end of a cross-capacitor C1 is connected to a common node between the coupled inductor L1 and the first switching tube S1, and a second end is connected to a first end of the coupled inductor L2; the second end of the coupled inductor L2 is connected to the output voltage; a first end of a second switching tube S2 is connected to the first end of the coupled inductor L2, and a second end is connected to ground; an output filter capacitor C2 is connected in parallel between the output voltage terminal and ground; the cross-capacitor C1 achieves bidirectional energy transfer from input to output through alternating charge and discharge, thereby achieving opposite polarity between the input voltage and the output voltage; a sampling resistor Rs samples the current flowing through the switching tube S1 and is connected to the SENSE pin to achieve peak current control.

[0070] like Figure 3 As shown, the Vdd voltage obtained by polarity reversal of the DC-DC switching power supply is obtained by designing the integrated switch driver chip LT8641 with a Buck topology structure. It is configured in discontinuous conduction mode under low load and enters continuous conduction mode when the current output is above 500mA. An output inductor is set externally. The integrated switch driver chip LT8641 inputs a 32V voltage, and the input filter capacitor is connected between the input and ground. The SW pin of the integrated switch driver chip is connected to the first end of the output inductor, and the second end of the output inductor is connected to the output voltage to achieve voltage reduction. The desired output voltage conversion is achieved by connecting the voltage divider network through the FB pin.

[0071] In some specific embodiments, the LDO voltage regulator module is configured to perform low voltage difference regulation on the output voltages Vdd and Vss of the DC-DC switching power supply module to supply power to the subsequent bipolar output voltage-controlled current source module.

[0072] In some specific embodiments, the current setting module uses a 16-bit analog-to-digital conversion chip DAC8734, an external reference input 5V reference voltage, and simultaneously outputs four-channel, ±10V bipolar voltage. The current setting module is connected to the microcontroller module via an SPI communication bus.

[0073] In some specific embodiments, the input end of the voltage follower circuit of the bipolar output voltage-controlled current source module is connected to the output end of the current setting module, and the output end of the bipolar output voltage-controlled current source module is connected to the input end of the inverting proportional circuit;

[0074] The operational amplifier is used to amplify the error between the input voltage signal and the output current signal;

[0075] The power amplifier is used to output bipolar power current;

[0076] The instrument amplifier is used to convert the current signal on the sampling resistor into a voltage signal, which is used as the negative input terminal of the error amplifier after amplification;

[0077] The sampling resistor is used to sample the output current signal and convert it into a voltage signal to transmit to the digital acquisition module.

[0078] like Figure 5 As shown, in some specific embodiments, the analog compensation network module is used to perform loop compensation on the error-amplified signal.

[0079] It should be understood that the analog compensation network module is composed of a resistor-capacitor network Z1 and a resistor-capacitor network Z2. Z1 is composed of a resistor R21 and a capacitor C2 connected in series, and then in parallel with a resistor R22. Z2 is composed of a resistor R23. The introduction of capacitor C2 improves the phase margin and closed-loop gain, thereby improving the speed and stability of the bipolar output voltage-controlled current source module.

[0080] In some specific embodiments, the digital acquisition module uses a multi-channel high-precision digital-to-analog conversion chip AD7689, one acquisition channel is connected to the output voltage signal of the current setting module, and the other acquisition channel acquires the current sampling signal of the bipolar output voltage-controlled current source module;

[0081] The digital acquisition module is connected to the microcontroller module via the SPI bus, and transmits the acquired two-way voltage digital signals for current state monitoring.

[0082] In some specific embodiments, the microcontroller module communicates with the current setting module and the digital acquisition module via SPI to set the current and read the actual current value.

[0083] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. An active magnetically compensated bipolar current source drive system, characterized in that: include: Pre-stage filtering and protection module, DC-DC switching power supply module, LDO voltage regulator module, analog compensation network module, bipolar output voltage-controlled current source module, microcontroller module, current setting module, digital acquisition module, including: The pre-stage filtering and protection module is configured to perform EMI filtering on the input primary power supply, reduce differential mode and common mode interference through X / Y capacitors, and protect the post-stage circuit with a surge suppressor; The DC-DC switching power supply module is configured to perform power conversion on the voltage after the pre-stage filtering; The LDO voltage regulator module is configured to perform low voltage difference regulation on the output voltage of the DC-DC switching power supply module, provide Vdd and Vss voltages for the front stage of the bipolar output voltage-controlled current source module, reduce switching ripple noise, and provide the power supply voltage required by the current setting module and the digital acquisition module; The current setting module is used to set the current output size of the bipolar output voltage-controlled current source module; The microcontroller module is configured to control the DAC via the SPI bus and perform digital settings; The bipolar output voltage-controlled current source module is composed of an operational amplifier, an instrumentation amplifier, a sampling resistor, and a power amplifier. The front-stage Vdd and Vss are set near the maximum power consumption critical point of the power amplifier to increase the bandwidth of the output current. The analog compensation network module is configured to perform error amplification and loop compensation on the control voltage output by the current setting module and the output voltage of the instrumentation amplifier; The digital acquisition module is configured to monitor the system output current and communicate with the microcontroller module via SPI to upload current data in real time; The microcontroller module is used to drive the system output current setting and output current data collection.

2. The active magnetic compensation bipolar current source drive system according to claim 1, characterized in that: The pre-stage filtering and protection module is composed of a fuse, a TVS diode, a differential mode capacitor, a common mode inductor, a Y capacitor, an EMI filter and a surge suppressor.

3. The active magnetic compensation bipolar current source drive system according to claim 2, characterized in that: The DC-DC switching power supply module includes: A first integrated switch driver chip, a second integrated switch driver chip and peripheral circuits thereof; The first integrated switch driver chip has a 32V input voltage, an input filter capacitor is connected between the input and ground, the SW pin of the integrated switch driver chip is connected to the first end of the output inductor, the second end of the output inductor is connected to the output voltage for step-down, and the FB pin is connected to a voltage divider resistor network for desired output voltage conversion; The second integrated switch driver chip has a 32V input voltage for voltage polarity reversal, and its input is connected to the first end of the coupled inductor L1; the first switch transistor S1 is connected to the second end of the coupled inductor L1; the first end of the jumper capacitor C1 is connected to the common node of the coupled inductor L1 and the first switch transistor S1, the second end of the jumper capacitor C1 is connected to the first end of the coupled inductor L2, and the second end of the coupled inductor L2 is connected to the output voltage; the first end of the second switch transistor S2 is connected to the first end of the coupled inductor L2, and the second end of the second switch transistor S2 is connected to ground; An output filter capacitor C2 is connected in parallel between the output voltage terminal and the ground; The cross-capacitor C1 is configured to transfer energy bidirectionally from input to output by alternately charging and discharging; The sampling resistor Rs is configured to sample the current flowing through the first switch tube S1 and is connected to the SENSE pin to control the peak current.

4. The active magnetic compensation bipolar current source drive system according to claim 3, characterized in that: The LDO voltage regulator module is configured to perform low voltage difference regulation on the output voltages Vdd and Vss of the DC-DC switching power supply module to supply power to the subsequent bipolar output voltage-controlled current source module.

5. The active magnetic compensation bipolar current source drive system according to claim 4, characterized in that: The current setting module uses a 16-bit analog-to-digital conversion chip DAC8734, an external reference input 5V reference voltage, and simultaneously outputs a four-channel, ±10V bipolar voltage. The current setting module is connected to the microcontroller module via an SPI communication bus.

6. The active magnetic compensation bipolar current source drive system according to claim 5, characterized in that: The input end of the voltage follower circuit of the bipolar output voltage-controlled current source module is connected to the output end of the current setting module, and the output end of the bipolar output voltage-controlled current source module is connected to the input end of the inverting proportional circuit; The operational amplifier is used to amplify the error between the input voltage signal and the output current signal; The power amplifier is used to output bipolar power current; The instrument amplifier is used to convert the current signal on the sampling resistor into a voltage signal; The sampling resistor is used to sample the output current signal and convert it into a voltage signal to transmit to the digital acquisition module.

7. The active magnetic compensation bipolar current source driving system according to claim 6, characterized in that: The analog compensation network module is used to perform loop compensation on the error-amplified signal.

8. The active magnetic compensation bipolar current source driving system according to claim 7, characterized in that: The digital acquisition module uses a multi-channel high-precision digital-to-analog conversion chip AD7689, one acquisition channel is connected to the output voltage signal of the current setting module, and the other acquisition channel acquires the current sampling signal of the bipolar output voltage-controlled current source module; The digital acquisition module is connected to the microcontroller module via the SPI bus, and transmits the acquired two-way voltage digital signals for current state monitoring.

9. The active magnetic compensation bipolar current source driving system according to claim 8, characterized in that: The microcontroller module communicates with the current setting module and the digital acquisition module via SPI to set the current and read the actual current value.

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