119 results about "Self excited oscillation" patented technology

The invention discloses a joint heat dissipation structure and a robot in the technical field of robots. The joint heat dissipation structure comprises a joint, the joint is provided with a shell, a containing cavity is formed in the inner side of the shell, a motor is fixedly arranged in the containing cavity, the joint heat dissipation structure is further provided with a heat dissipation assembly used for reducing the temperature in the containing cavity, the heat dissipation assembly is a pulsating heat pipe, and the pulsating heat pipe comprises an evaporation section and a condensation section. The evaporation section is attached to the outer wall of the motor, and the condensation section is attached to the inner wall of the shell. The pulsating heat pipe is used for heat dissipation, based on the phase change heat transfer principle, no extra fan or pump is needed, self-oscillation flowing is achieved completely through thermal driving, and the overall energy consumption of the robot is remarkably reduced. The pulsating heat pipe is small in occupied space, light in weight, simple in structure, low in maintenance cost and suitable for long-term operation, and joint movement flexibility and load capacity are effectively improved; the condensation section is attached to the inner wall of the shell, the joint shell can be heated while heat dissipation is conducted, and the warm touch feeling can be provided without extra energy consumption.

The invention provides a multi-feedback-channel fluid oscillator, and belongs to the technical field of fluid jetting devices. Comprising an oscillation cavity, an inlet, a nozzle and at least three feedback channels, the inlet is formed in one end of the oscillation cavity, the nozzle is formed in the other end of the oscillation cavity, the nozzle and the inlet are oppositely arranged along the central axis of the oscillation cavity, and the feedback channels are circumferentially distributed around the central axis of the oscillation cavity. And each feedback channel is provided with a feedback channel inlet and a feedback channel outlet. Through the configuration design of the multiple feedback channels, the fluid can form feedback control flow through the feedback channels, and the fluid entering the oscillation cavity through the inlet flows along the wall of the oscillation cavity in multiple directions and is switched through the coupling effect of the fluid coanda effect and multi-channel backflow feedback. And finally, multi-direction sweeping self-oscillation jet flow is formed at the nozzle, so that the space coverage range and the atomization efficiency of the jet flow are greatly improved.

The invention provides a self-excited cesium optical pump atomic magnetometer and a magnetic field measurement method. The magnetometer comprises a physical probe part and a circuit part. The physical probe part comprises a cesium spectrum lamp, an optical element, a cesium atom absorption gas chamber, a radio frequency coil and a photoelectric detector; the circuit part comprises a photoelectric conversion circuit, a phase-locked amplification circuit and a radio frequency excitation circuit modulated by square waves. A macroscopic magnetic moment is generated by pumping cesium atoms through left-handed circularly polarized light, a radio frequency magnetic field induces Larmor precession, light intensity changes are detected and fed back to a radio frequency coil to form self-oscillation, and the external magnetic field intensity is calculated according to the linear relation between oscillation frequency and the magnetic field. Square wave modulation is adopted to broaden the measurement bandwidth, a magnetic field direction adjusting system is additionally arranged to automatically keep an angle of 45 degrees between an optical axis and a magnetic field so as to eliminate a blind area, the hemisphere automatic switching function is achieved, and the advantages of being high in sensitivity, fast in response, high in adaptability, small in size and low in power consumption are achieved.

The invention provides a handheld shock wave generating system which comprises a shock wave balloon and a driving circuit, and the driving circuit comprises a primary power supply circuit, a high-voltage booster circuit, a voltage doubling circuit and a control circuit. After a voltage signal VCCS2 output by the primary power supply circuit is subjected to self-oscillation and boosting of the high-voltage boosting circuit and multiple rounds of voltage multiplication of the voltage doubling circuit, the voltage signal VCCS2 can be increased by hundreds or even thousands of times, a storage battery and a mains supply do not need to be used, miniaturization can be achieved, and carrying is convenient.

The invention provides an ultra wide band millimeter wave transition structure based on gold wire bonding, and relates to the technical field of millimeter wave chip packaging, and the transition structure comprises a substrate, a rectangular cavity, a chip, a parallel gold wire connection structure, a stepped grounding coplanar waveguide GCPW matching structure, and a plurality of blind holes. The substrate comprises a top dielectric layer, a middle metal layer and a bottom metal layer, the rectangular cavity is arranged on the top dielectric layer; the chip is fixed in the rectangular cavity; the parallel gold wire connecting structure is used for connecting the chip and the stepped grounding coplanar waveguide GCPW matching structure; and the plurality of blind holes vertically penetrate through the substrate, are positioned in an area right below the edge of the rectangular cavity and gold wire bonding, are connected with the middle metal layer and the bottom metal layer, and are used for suppressing self-excited oscillation. According to the method provided by the invention, the transition from the chip to the substrate with the average loss lower than 0.28 dB is realized within the frequency band of 30-100GHz.

The invention relates to an audio decoding output stage circuit and audio equipment, the audio decoding output stage circuit comprises an I / V conversion module and a low-pass filtering module, and the I / V conversion module comprises a conversion circuit, a crossed diamond amplification circuit, an overcurrent protection circuit and a Roche network circuit; the conversion circuit comprises a JFET (Junction Field Effect Transistor) audio operational amplifier chip and an I / V (Input / Output) conversion resistor and is used for converting an input current into an analog voltage signal; the crossed diamond amplifying circuit can reduce the input offset voltage; the over-current protection circuit can carry out over-current protection; the rowbell network circuit can prevent high-frequency self-oscillation of the power output stage; and the low-pass filtering module comprises a filtering circuit and an ultrahigh frequency filtering circuit arranged at the output end of the audio decoding output stage circuit. The scheme can bring high-performance sound performance, and has the advantages of lower distortion, higher conversion rate, low output impedance and large pushing current.

The application provides a salt-preventing ocean high-pressure water pump port ring structure based on coupled oscillation, and belongs to the technical field of ocean water pump equipment, and comprises a pump body port ring and an impeller port ring, and an annular gap is formed between the two; a nozzle-shaped first groove is arranged on the inner circumferential surface of the pump body port ring, and a second groove with an inclined wall surface and a backflow channel is arranged on the outer circumferential surface of the impeller port ring; the first groove and the second groove are connected to form a fluid oscillation channel. Through the matching design of the circumferential interval of the groove and the rotating speed of the impeller, the groove connection-separation frequency reaches the ultrasonic frequency band, and double coupling of fluid self-excitation oscillation and ultrasonic vibration is realized. The application effectively prevents salt deposition under the premise of not changing the existing lubrication mode, and significantly improves the water film lubrication performance and the service life of the equipment.

This invention relates to a ball-operated plugging device for downhole pulsating hydraulic fracturing, comprising a main body assembly. A conical valve seat is disposed in the middle of the main body assembly, and an umbrella-shaped valve is slidably connected within the conical valve seat. The umbrella-shaped valve includes a valve head boss and a valve stem. A self-excited oscillation chamber is also provided at the bottom of the conical valve seat. A spring support seat is disposed below the self-excited oscillation chamber, with a central circular hole at the geometric center of the spring support seat. A spring is placed on the spring support seat, and the top of the spring contacts the valve head boss of the umbrella-shaped valve. A through-hole flow channel is provided in the middle of the umbrella-shaped valve, with its upper and lower ends communicating with cavity A and cavity B, respectively. The valve stem of the umbrella-shaped valve passes through the spring, and its bottom is inserted into the central circular hole of the spring support seat. A spherical groove is provided at the top of the umbrella-shaped valve for placing a soluble plugging ball. This invention can adjust the pressure variation of the pulsating fluid at the bottom of the well during construction.

The application discloses a kind of digital frequency tracking and synchronous sampling control system for resonant gyro, including self-excitation oscillation and automatic gain control device, preamplifier circuit and digital signal processor, digital signal processor includes first A / D conversion unit, second A / D conversion unit, frequency error detection unit FD, phase error detection unit PD, digital control oscillator NCO, sampling frequency generator and quadrature demodulation unit, the vibration signal of drive channel is handled after device output to first A / D conversion unit, conversion obtains the vibration signal after conversion, FD obtains frequency difference by frequency error detection, PD obtains phase difference by phase error detection, NCO is adjusted the frequency and phase of sampling frequency generator according to frequency difference and phase difference in real time, until the resonant frequency and phase of drive channel are tracked;The vibration signal of detection channel is handled after circuit output to second A / D conversion unit, obtains the vibration signal after conversion, and quadrature demodulation unit carries out quadrature demodulation and obtains speed signal.

This invention relates to the field of flow battery technology and discloses a method and system for regulating self-excited oscillation in flow batteries. By integrating a flow oscillation generator into the electrolyte circulation loop of the flow battery, the periodic vortex ring oscillation and acoustic-fluid positive feedback phenomenon generated by the flow within the resonant cavity of this device are utilized to achieve pulsating regulation of electrolyte flow rate and pressure. This fundamentally improves the convective mass transfer efficiency at the electrode / electrolyte / diaphragm interface within the flow battery stack, thereby alleviating concentration polarization at the battery reaction interface caused by factors such as uneven flow rate, thickened diffusion boundary layer, and restricted ion migration. Furthermore, this device eliminates the need for long-term, additional electrical drive and complex control components, exhibiting a simple structure and stable operation.

The application relates to a zero-flux closed-loop circuit, which comprises a self-oscillating fluxgate current sensor, a magnetic integrator and a feedback circuit; wherein the self-oscillating fluxgate current sensor can generate a magnetic field signal under the action of an excitation current, the magnetic integrator can generate a corresponding voltage signal according to the magnetic field signal, the feedback circuit can generate a feedback signal according to the corresponding magnetic field intensity of the voltage signal, and the feedback signal acts on the self-oscillating fluxgate current sensor, so that the self-oscillating fluxgate current sensor adjusts the excitation current, thereby ensuring that the magnetic flux of a fluxgate through the self-oscillating fluxgate current sensor is kept near a zero-flux point. Therefore, the zero-flux closed-loop circuit can effectively reduce the influence of noise and the distortion degree of a signal when detecting the current of a current-carrying wire in a zero-flux environment, thereby improving the precision of current detection.

The utility model relates to a kind of load impedance measurement circuit, system and equipment, including waveform control circuit, load impedance acquisition circuit, signal amplification circuit, analog signal conversion PWM circuit, filter circuit and MCU connected in turn;Waveform control circuit includes self-oscillation circuit and rectangular wave output circuit, rectangular wave output circuit receives the rectangular wave that self-oscillation circuit exports and reference voltage comparison generates complementary rectangular wave output to load impedance acquisition circuit, load impedance acquisition circuit gathers load impedance and exports direct current signal to signal amplification circuit, analog signal conversion PWM circuit gathers amplified signal conversion as digital signal to filter circuit and carries out filter processing, and MCU receives the signal after filter processing of filter circuit.The utility model uses self-oscillation and complementary rectangular wave output circuit to form sampling circuit combination, the signal gathered is more accurate, and it is easy to be read and further processed by lower circuit, and finally the impedance measurement value of equipment is more accurate.

The application provides a power amplifier packaging structure. The power amplifier packaging structure comprises a power amplifier chip, a substrate, a wall, a transmission ceramic, a transmission lead and a cover plate; the power amplifier chip is arranged on the upper surface of the substrate; the wall is arranged around the power amplifier chip and is connected with the upper surface of the substrate; a plurality of through holes are arranged on the side surface of the wall and at the connection position of the upper surface of the substrate; one end of the transmission ceramic is arranged on the inner side of the side surface of the wall through the through holes and is connected with the corresponding pin on the power amplifier chip respectively, and the other end is arranged on the outer side of the side surface of the wall and is connected with the transmission lead respectively; the cover plate is arranged on the upper surface of the wall; and the cover plate is made of ceramic. The application can effectively eliminate the low-temperature self-excitation oscillation phenomenon of the power amplifier.

The application provides a vertical state carrier rocket self-excitation oscillation suppression network design method, mainly including a vertical state carrier rocket dynamics model construction and a vertical state carrier rocket self-excitation oscillation suppression method. Aiming at the self-excitation oscillation phenomenon in the target test of the carrier rocket in the vertical state, a carrier rocket self-excitation oscillation suppression method is provided. Firstly, a vertical state carrier rocket dynamics model is established; then frequency domain analysis is carried out based on the dynamics model; finally, a dithering elimination network is designed and time domain simulation verification is carried out. The method can effectively solve the self-excitation oscillation phenomenon in the target test of the carrier rocket in the vertical state, eliminate the influence of the periodic dithering of the carrier rocket on the loaded rocket product, and effectively ensure the safety of the rocket ground test and take-off.

The invention discloses a self-driven high-frequency induction heating circuit structure suitable for in-situ pyrolysis in an oil-rich coal well, and relates to the technical field of pyrolysis. The circuit structure comprises an uncontrolled rectifying circuit, a self-driven high-frequency inverter circuit and an induction heating coil, the uncontrolled rectifying circuit converts an alternating current power supply into direct current and is connected to a power supply node VCC2; the self-driven high-frequency inverter circuit is composed of a main circuit, a self-driven protection circuit and an output circuit, the main circuit comprises an upper bridge arm structure and a lower bridge arm structure, the self-driven protection circuit achieves automatic driving of a switching device through a pull-down unit, a pull-up unit and a turn-off guide unit, and the output circuit comprises a resonant capacitor set and two inductors. The induction heating coil is connected between the VCC1 and the VCC. According to the scheme, self-oscillation is achieved by means of inconsistency of device parameters, direct current is converted into high-frequency alternating current, a control chip and a detection circuit are omitted, the system structure is simplified, and the operation reliability in the underground high-temperature and high-humidity environment is improved.

A self-excitation microwave sensor suitable for non-destructive testing of metal mesh film, belonging to microwave sensor technology, comprising a resonant sensing structure, a microwave amplifier, a phase shift element, a band-pass filter, a radio frequency detector, a digital-to-analog converter and a microprocessor; wherein the resonant sensing structure, the microwave amplifier, the phase shift element and the band-pass filter form a self-excitation oscillation loop, the resonant sensing structure has a band-pass characteristic, is located in the feedback branch of the loop, the resonant frequency thereof is consistent with the center frequency of the band-pass filter, and the loop gain and the phase shift satisfy the self-excitation oscillation condition at the frequency; by reasonably setting the gain of the microwave amplifier and collecting the self-excitation oscillation signal power in real time, the sensor can realize detection of sub-millimeter width crack damage and identification of high square resistance samples, has high detection sensitivity, compact structure, small volume and low cost, does not need other external microwave analysis instruments, and can be applied to on-site non-destructive testing of metal mesh film.

The utility model discloses a leakage current detection circuit suitable for a photovoltaic grid-connected inverter. The leakage current detection circuit comprises an AC sampling transformer, a DC sampling mutual inductor, a self-oscillation circuit, an amplification circuit, a digital signal processing unit and a switching circuit. The direct current sampling mutual inductor is combined with the self-oscillation circuit to carry out high-frequency processing on a direct current leakage current signal, and the direct current leakage current signal and an alternating current signal output by the alternating current sampling transformer are jointly transmitted to the amplifying circuit and the digital signal processing unit, so that integrated detection of alternating current and direct current leakage current is realized. The high-frequency processing of the self-oscillation circuit optimizes the leakage current detection capability in a broadband range, the amplification circuit has a dynamic gain adjustment function, the filter effectively suppresses noise interference, and the digital signal processing unit rapidly cuts off a power supply through intelligent threshold judgment and control of the signal output module. According to the overall technical scheme, through deep cooperation of multiple modules, the detection precision, the anti-interference capability and the safety performance are improved, the circuit structure is simplified, and the cost is reduced.

This invention discloses a casting apparatus and casting process for lead-free brass water meter housings, relating to the field of brass casting technology. It includes a main body, a fixing unit, a pretreatment unit, a pneumatic unit, and a control unit. The fixing unit clamps the water meter housing; the control unit monitors the casting temperature in real time via a temperature sensor. When the water meter housing is in the hot brittle range above 300°C, the air supply unit only outputs airflow for gentle cooling to prevent deformation and cracking of the casting. When the temperature drops to 200°C from 300°C, the air supply unit outputs high-pressure airflow to drive a vibrating unit, using high-frequency self-excited oscillation to break down and peel off the internal molding sand. When the temperature drops below 200°C, the air supply unit outputs pulsed airflow to drive a striking unit, reciprocatingly striking the outer wall of the water meter housing to remove residual molding sand. Finally, the extraction unit uses negative pressure to extract and separate the molding sand. This invention solves the problem of easy damage or difficult sand removal of lead-free brass water meter housings at different cooling stages, achieving efficient and non-destructive sand removal.

The invention relates to a high-voltage direct-current generation circuit of a plasma generator. The high-voltage direct-current generation circuit comprises a first rectifying unit, a filtering unit, a self-oscillation unit, a boosting unit and a second rectifying unit, and the self-excited oscillation unit is used for inverting the second direct current into the second alternating current. And the boosting unit is used for boosting the second alternating current to obtain a third alternating current. And the second rectifying unit is used for rectifying the third alternating current to obtain a third direct current. The self-oscillation unit comprises at least one pair of switch tubes and a positive feedback winding. The self-oscillation unit comprises at least one pair of switching tubes and a positive feedback winding, and the positive feedback winding provides induced positive feedback current for the control ends of the switching tubes under the condition that current in a primary winding of a transformer is increased, so that the switching tubes are gradually changed from a micro-conduction state to a conduction state. And the burnout phenomenon caused by sudden conduction of the switch tube can be avoided.

The invention discloses an isolation feedback circuit based on magnetic saturation self-oscillation, which is applied to a DC / DC module power supply with a preceding-stage PWM control circuit, and comprises a self-oscillation circuit, a voltage and current conversion circuit, a low-pass filter circuit and a signal acquisition circuit, the self-oscillation circuit comprises a saturation inductor and an asymmetric circuit; the input end of the voltage and current conversion circuit is connected with the output voltage end of the DC / DC module power supply, and the output end of the voltage and current conversion circuit is connected with a secondary winding of the self-oscillation circuit; the input end of the low-pass filter circuit is connected with the signal output end of the self-excited oscillation circuit, and the output end of the low-pass filter circuit outputs a feedback voltage signal; the input end of the signal acquisition circuit is connected with the output end of the low-pass filter circuit, and the output end of the signal acquisition circuit is connected with the preceding-stage PWM control circuit. The defect that an optical isolation scheme is insufficient in radiation resistance is overcome, the integration level and the response speed of the whole circuit are improved, and the reliability requirement of spaceflight long-life application is met.

The application discloses a corona discharge load state detection method based on an oscillation circuit voltage ratio relationship and relates to the technical field of corona discharge detection. An ideal Royer circuit is constructed; a peak value protection circuit is used for collecting a peak voltage Vm; a direct current input voltage of a sine wave self-excitation oscillation boost circuit is Vin; a ratio relationship of Vm and Vin in the ideal Royer circuit under no-load is calculated to obtain a first relationship formula; a ratio relationship of Vm and Vin in the ideal Royer circuit under load is calculated to obtain a second relationship formula; first-order linear approximation fitting is performed on the first relationship formula and the second relationship formula to obtain a target relationship formula; and the corona discharge load state is determined according to the target relationship formula. Through establishing a quantitative relationship between the ratio of the peak voltage of the primary side of the Royer circuit which is easy to measure and the input voltage and the secondary direct current high voltage and the load current reflecting the needle tip state, safe, quantitative and adaptive contamination detection is realized.

This invention relates to the field of ultrasonic motor drive technology, and discloses a micro-driver for an ultrasonic motor based on the principle of self-excited oscillation and its usage method. The driver includes: an amplification circuit module, comprising a voltage series negative feedback amplification circuit composed of integrated operational amplifiers, the output of which is connected to a feedback network via an inductor; a temperature compensation module, which directly senses temperature changes through the equivalent circuit of the ultrasonic motor and dynamically adjusts circuit parameters; and a frequency selection network module, composed of three impedance elements, which are respectively connected to the temperature compensation module, the amplification circuit module, and the feedback network module. By utilizing the self-excited oscillation principle and the feedback characteristics of the ultrasonic motor, a complex external frequency tracking loop is eliminated, simplifying and miniaturizing the circuit design. The temperature compensation module automatically adjusts the driving frequency, achieving adaptability to resonant frequency drift. Optimized feedback network reduces power consumption and improves driving efficiency.

This invention discloses a thermally excited piezoresistive self-excited resonant inertial sensor, belonging to the field of microelectromechanical systems (MEMS). It comprises an integrated inertial force sensing module, a frequency modulation module, and a self-excited oscillation module. The inertial force sensing module senses acceleration and converts it into an axial force applied to the frequency modulation module. The frequency modulation module changes its effective stiffness by receiving the axial force, thus completing frequency modulation. The self-excited oscillation module generates alternating thermal expansion force through its own closed loop, achieving self-excited oscillation of the frequency modulation module under the action of this alternating thermal expansion force. This invention solves the problem of the lack of transverse vibration mode accelerometers both domestically and internationally by coupling the resonator with a DETF beam. It also avoids the problem of the resonator's transverse vibration mode aligning with the accelerometer's mass motion direction, which could affect the overall acceleration mode and reduce sensitivity.

This invention relates to a self-oscillating closed-loop voltage regulator circuit, comprising a self-oscillating circuit, a primary power supply undervoltage indicator circuit, a secondary power supply undervoltage indicator circuit, a key valid indicator circuit, a power amplifier circuit, and a boost control circuit. The self-oscillating circuit outputs a fixed-frequency reference square wave signal. Undervoltage, overvoltage, and key valid indicator signals are passed through an AND gate to output a variable-frequency square wave signal. This variable-frequency square wave signal is then passed through a complementary pull-up circuit to increase the driving capability. The complementary output variable-frequency square wave controls the boost circuit. When the battery is low or the secondary power supply is undervoltage, the output frequency of the self-oscillating circuit controls the switching of the boost circuit to achieve rapid voltage boost. When the battery and secondary power supply voltages are normal, the boost control circuit is shut down. This effectively ensures stable operation under normal control conditions and is particularly suitable for the automotive electronics industry.

This invention belongs to the technical field of engineering vibration control and discloses a real-time suppression method for low-frequency oscillations based on a fully closed-loop servo drive system. The invention utilizes dual encoder feedback on the motor and load sides to extract the position deviation signal, which is then input to a PD compensator with a first-order low-pass filter. The output of this compensator is superimposed on the torque command side to suppress low-frequency self-excited oscillations caused by nonlinear factors. Based on this, the fully closed-loop system is equivalent to a second-order model, and its natural frequencies are identified. ω Based on the damping ratio and the tolerable oscillation level, the input shaper pulse sequence is designed to convolve and shape the original position command, suppressing low-frequency residual oscillations. Simultaneously, the differential and second-order differential signals of the command are shaped and used in conjunction with the feedforward gain to generate the speed and acceleration feedforward amount, compensating for the time delay introduced by the shaper. This invention achieves real-time suppression of low-frequency oscillations under all operating conditions through the synergistic effect of feedforward shaping and feedback compensation, making it easy to deploy and apply in industrial servo drives.

This invention discloses an adaptive constant temperature control method and system for circulating water pumps based on ambient temperature, relating to the field of adaptive constant temperature control. The method involves acquiring the spatial structural parameters of an air conditioning cooler, constructing a three-dimensional thermal and humid air motion model coupling exhaust and intake airflows, generating a potential energy field for the risk of exhaust hot and humid air mass recirculation based on the three-dimensional thermal and humid air motion model, and combining real-time ambient temperature, forecast temperature, and meteorological boundary conditions to perform recirculation self-excited oscillation detection. A corrected equivalent ambient temperature is output to eliminate recirculation self-interference deviation. Using the corrected equivalent ambient temperature as a feedforward variable, a target operating current setpoint for the water pump is generated through a compensation function that compensates for the inverse relationship between the pump operating current and ambient temperature. After smoothing and filtering, the setpoint is output to the variable frequency drive of the circulating water pump. The variable frequency drive adjusts the output frequency according to the current setpoint to ensure that the pump operating current tracks the setpoint, maintaining a constant cooling water supply temperature.

The invention provides a pulse laser pumping cesium atom magnetometer and a measuring method. The magnetometer comprises a physical probe part and a circuit part. The physical probe comprises a VCSEL laser, an optical element, a cesium atom absorption gas chamber, a radio frequency coil and a photoelectric detector; the circuit part comprises a photoelectric conversion circuit, a differential amplification circuit and a radio frequency excitation circuit. The method comprises the following steps: carrying out optical pumping on cesium atoms by adopting pulse laser, inducing magnetic resonance through a radio frequency field, detecting precession signals by utilizing a time division multiplexing mechanism, forming self-oscillation through differential amplification and feedback, and calculating the external magnetic field intensity through oscillation frequency. The invention further provides a scheme for adaptively switching between a high-sensitivity working mode and a wide-bandwidth working mode based on the change degree of a magnetic field measurement value and a scheme for accumulatively detecting a magnetic field for mobile platform application. The invention has the characteristics of high sensitivity, large bandwidth, small volume and low power consumption, and is suitable for geomagnetic field and magnetic field measurement in a wider range.

The application relates to a self-excitation oscillation magnetic flux gate sensor and a measuring system, and relates to the technical field of measuring electric variables. The self-excitation oscillation magnetic flux gate sensor comprises a detection component connected with a measured wire and used for sensing a measured electric signal on the measured wire; a measurement and control circuit used for providing a control signal; a feedback filter circuit connected with the measurement and control circuit, used for filtering and processing the control signal and outputting a reference signal, and used for adjusting the output reference signal according to the reference signal and the filtered control signal; a driving excitation circuit connected with the detection component, the feedback filter circuit and the measurement and control circuit respectively, used for self-excitation oscillation according to the reference signal and the measured electric signal, and used for generating an excitation current; and the measurement and control circuit is further used for determining a measurement value of the measured electric signal according to the excitation current. The application can improve the measurement precision.

This invention provides a method for dynamically adjusting the current distribution of feeders in a distribution cabinet, relating to the field of distribution cabinet technology. By real-time acquisition and fusion of contact temperature, feeder current, and cabinet humidity data, the method identifies target feeders with current deviations and detects the starting moment when the current distribution changes from unidirectional deviation to reciprocating alternating oscillations. Combining fluctuation amplitude clustering and critical humidity cross-comparison, the method determines the feeder group that needs immediate adjustment and simultaneously executes bus tie switch switching, adjustable shunt branch capacity configuration, and heating and dehumidification module activation. This solves the problem of unpredictable and uncontrollable self-excited oscillating current fluctuations caused by dynamic changes in contact resistance due to contact oxidation, effectively suppressing repeated current transfers between feeders and improving the stability of current distribution and power supply safety and reliability in the distribution cabinet.