11174 results about "Inductance" patented technology

The invention discloses a plug-in inductor winding process control method based on production parameter dynamic compensation, and provides a closed-loop compensation control strategy taking a physical field evolution model as a core aiming at the problems of unstable sensing quantity and non-uniform structure in the traditional process. The method comprises the following steps: firstly, constructing an ideal physical field reference model according to target inductance parameters and a structure, and describing an evolution law of characteristics such as a magnetic field, an electric field or impedance in an ideal state; in the actual winding process, a physical field signal is collected through a sensor, production parameters such as wire tension and main shaft rotating speed are obtained, and a physical field distribution snapshot of the current winding state is generated. And the system compares the extracted actual features with the reference model, identifies a dominant disturbance source causing deviation in combination with real-time production parameters, and outputs a disturbance type label carrying causal information. And according to a label and a production parameter change trend, a compensation instruction is dynamically generated and executed, fine adjustment of tension, a winding displacement track or density is realized, and consistency and precision of an inductor finished product are ensured.

The invention discloses a grinding machine internal part temperature anomaly detection method based on vibration signal analysis, which comprises the following steps that grinding data are collected through sensor deployment, and the sensors comprise a temperature sensor, a vibration sensor, an infrared thermal imaging sensor, a magnetic resistance current sensor and an inductance type particle sensor; carrying out preprocessing and feature extraction on the collected data; model construction and training are carried out based on data of preprocessing and feature extraction; according to the method, the abnormal condition of the temperature of the part is predicted by detecting the vibration signal of the internal part, the content of metal particles in lubricating oil is detected through the oil analysis sensor, and the abrasion degree of the bearing is judged in combination with the vibration signal. And motor current harmonic characteristics are monitored, and overload or rotor imbalance problems are identified.

The invention discloses an error compensation inductance sensor calibration method and system, and the method comprises the steps: controlling a macro-micro composite driving platform to drive a moving part provided with a to-be-calibrated inductance sensor, and enabling the moving part to carry out the continuous displacement movement relative to a fixed standard target surface; measuring the actual displacement of the moving part to obtain a standard displacement sequence; the actual output voltage of the inductive sensor to be calibrated in the movement process is synchronously collected, and an actual measurement value sequence is formed; solving measurement deviation, generating a measurement deviation sequence, and dividing the sequence into not less than three compensation intervals according to a displacement range; a compensation value lookup table is established in each compensation interval, and calibration parameters used for correcting zero offset, gain drift and nonlinear characteristics are generated. Displacement measurement and sensor output synchronous acquisition are combined, zero offset, gain drift and non-linear errors can be corrected in a targeted mode, and compensation fineness and adaptability are improved.

The invention relates to the technical field of power electronics, in particular to a voltage ripple suppression and compensation method for a multi-output AC-DC switching power supply, and the method comprises the steps: obtaining the real-time voltage ripple signal of each AC-DC output channel and the working parameters of the switching power supply, and the working parameters comprise the switching frequency, the duty ratio, the inductance and capacitance parameters and the load current; inputting the real-time voltage ripple signal and the working parameters of the switching power supply into a preset coupling interference model, and generating ripple coupling characteristics between AC-DC output channels; determining a ripple suppression compensation coefficient through the ripple coupling characteristics; and based on the ripple suppression compensation coefficient and a preset PWM control signal, adjusting the output voltage of the switching power supply to suppress the ripple, thereby breaking through the limitation of a traditional method on independent processing of a single channel, and fundamentally solving the problem of a ripple suppression blind area caused by cross interference between channels.

The invention relates to the technical field of GIS equipment, and discloses a partial discharge detection method and device for totally-enclosed vacuum environment-friendly GIS equipment, and the method comprises the steps: constructing a dual detection circuit system of the GIS equipment, and building an equipment impedance characteristic model which comprises housing distribution inductance and internal conductor distribution inductance; acquiring a first multi-mode discharge signal in a vacuum insulation environment, performing empirical mode decomposition to obtain a plurality of eigenmode function components, and synchronously recording environment characteristic parameters; constructing a discharge signal identification model; and identifying the second multi-mode discharge signal of the GIS equipment through the discharge signal identification model, and determining the internal defect three-dimensional coordinate and the hazard level of the GIS equipment, so that intelligent identification of discharge characteristics is realized, the calculation efficiency is improved, the anti-interference capability is enhanced, the three-dimensional coordinate of the internal defect of the GIS equipment can be accurately calculated, and the reliability of the GIS equipment is improved. And comprehensive evaluation of defect types and hazard levels is realized.

The invention relates to a power supply module which comprises an inductance circuit, a switch circuit, a check driving circuit and a controller, wherein the inductance circuit is provided with an inductor and a voltage feedback line, and the voltage feedback line feeds back the end voltage of the inductor. The switch circuit is electrically connected with the inductance circuit to drive the inductance circuit. The check driving circuit is electrically connected with the switch circuit and the voltage feedback line, and the check driving circuit controls the switch circuit and generates a current feedback signal according to the end voltage of the inductor. The controller is electrically connected with the check driving circuit, and controls the check driving circuit according to the current feedback signal.

The invention relates to the technical field of energy storage, in particular to an energy storage converter which comprises a shell, the shell is provided with a first containing cavity, a second containing cavity and a third containing cavity which are distributed in the first direction, the first containing cavity is provided with an inductor, a radiator and a first cooling fan, and the second containing cavity is provided with a high-voltage box, a power device and a heating electronic device; the third accommodating cavity is provided with a control board, an anti-interference board and a power board; a first partition plate and a second partition plate which are distributed in a spaced mode in the second direction are arranged between the first containing cavity and the second containing cavity, the first partition plate can support the high-voltage box, and the second partition plate can support the heating electronic device; along a second direction, the power device is arranged between the first partition plate and the second partition plate, and the second direction is perpendicular to the first direction; a first supporting plate is arranged between the second containing cavity and the third containing cavity and supports the control plate, the anti-interference plate and the power panel. The energy storage converter is high in space utilization rate, small in size and high in operation stability.

Power converters including electronic-embedded transformers for current sharing and load-independent voltage gain are described. An example power converter system includes an input, an output, a power converter between the input and output, and a controller. The converter includes a first bridge, a second bridge, and an electronic-embedded transformer between the first and second bridge. The electronic-embedded transformer includes a bidirectional coupling switch bridge. The controller generates drive control signals for quasi-trapezoidal current modulation control of the bidirectional coupling switch bridge. The controller is configured to generate the drive control signals based on a commutation coefficient k and a switching frequency for the power converter. The commutation coefficient k can be set based on an inductance in the electronic-embedded transformer, a capacitance in the bidirectional coupling switch bridge, and a margin for resonant current commutation.

The invention relates to the technical field of resonance suppression, and discloses an active damping control LC resonance suppression method and device. The method comprises the following steps: performing parameter identification processing based on bus voltage to obtain an inductance value, a capacitance value and a resonance frequency of an LC circuit; extracting a resonant current component of the current signal based on the resonant frequency; calculating damping power according to the resonance current component, and converting the damping power into a voltage compensation instruction under an alpha-beta coordinate system; generating a PWM control signal according to the voltage compensation instruction and a voltage reference instruction; and performing on-off control on the inverter based on the PWM control signal, and injecting power opposite to the resonant current component into the LC circuit to generate a virtual damping effect. Virtual impedance characteristics are seamlessly integrated into inverter control, rapid response of the whole process from resonance detection to power injection is ensured, the resonance peak value is effectively suppressed, and the current quality is improved.

The invention discloses a dual-electric brake boosting system, which belongs to the technical field of vehicle brake control and comprises the following steps: S1, dynamically calculating quadrature-axis inductance parameters, generating a synchronous magnetic field signal and inhibiting electromagnetic interference of dual motors; s2, extracting a harmonic-rotating speed mapping relation, and dynamically correcting an observation equation to control a parameter error; s3, reconstructing neutral point voltage to counteract high-frequency jitter, and reducing residual harmonic interference through adaptive filtering; s4, establishing a three-dimensional thermal field to predict copper and iron loss, dynamically adjusting current and generating an inverse time limit protection curve; s5, splitting the hot parameters into parity check frames, optimizing a communication protocol and compressing a refresh cycle to 10ms; s6, overlapping response of the white noise excitation system, and performing closed-loop calibration on the filtering weight to improve the observation precision; s7, triggering an audible and visual alarm and synthesizing a directional voiceprint and a tactile pulse to ensure safety regulations and perception intensity; the method has the beneficial effects that the method has remarkable advantages in a high-temperature and high-vibration severe environment, and the reliability and the safety of a system can be improved.

The invention provides a COT step-down converter comprising an inductive current detection circuit configured to detect an inductive current flowing through an inductor connected to a system output of an output voltage of an output system of the COT step-down converter, and generate a current zero-crossing detection signal indicating whether the inductive current crosses zero, the inductive current zero-crossing means that the inductive current is changed from positive current to negative current; and a sleep mode control circuit configured to generate a sleep mode control signal for controlling one or more circuit modules in the COT buck converter to change from an operating state to a closed state based on the current zero-crossing detection signal, an output feedback voltage representing a system output voltage of the COT buck converter, and a predetermined reference voltage.

Some examples relate to a circuit including a plurality of input pins, a plurality of output pins, a pulse width modulated (PWM) controller, and an inductor-open detection circuit. The PWM controller has a plurality of inputs and a plurality of outputs. The plurality of inputs of the PWM controller are coupled to the plurality of input pins, and the plurality of outputs of the PWM controller are coupled to the plurality of output pins. The inductor-open detection circuit has an input coupled to a pin of the plurality of input pins, and has an output coupled to the PWM controller.

A conversion control circuit controls plural stackable sub-converters which are coupled in parallel to generate an output power to a load. The conversion control circuit includes a current sharing terminal and a current sharing circuit. A current sharing signal is connected, in parallel, to the current sharing terminals. The current sharing circuit includes: configuration (1): the current sharing signal is generated only according to an inductor current corresponding to one of plural inductors of the plural stackable sub-converters; or configuration (2): the current sharing signal is generated according to plural inductor currents corresponding to plural inductors of plural activated phases of the plural stackable sub-converters, wherein a ratio of a portion of the current sharing signal generated by a master control circuit to a portion generated by one of the slave control circuits is k which relates to a difference between a total phase number and an activated phase number.

The invention discloses a reclosing locking dynamic adjustment method and system based on voltage mutual inductance, and relates to the technical field of reclosing locking dynamic adjustment, and the method comprises the following steps: collecting the voltage waveform of a power system, and carrying out the power failure prediction if the system does not recover the power supply; acquiring cable equipment data and power grid load data when the power system breaks down; constructing a power system anomaly evaluation model based on machine learning according to the cable equipment data and the power grid load data; obtaining a node area power system abnormity evaluation coefficient with the voltage waveform higher than the stable voltage, and carrying out fault positioning on the node area based on a preset power system safety and stability coefficient; and judging whether locking operation is carried out or not, if the locking operation is carried out, acquiring the voltage waveform after maintenance and the abnormal evaluation coefficient of the power system to judge whether the fault is eliminated or not, and closing the locking of the reclosing. According to the invention, through reclosing locking dynamic adjustment, the problems that the locking time is too long and the fault type cannot be accurately identified are solved.

A low voltage ride through control method for a grid-forming inverter based on dynamic internal potential adjustment comprises the following steps: detecting a voltage per unit value of a grid-connected point in real time, and comparing the voltage per unit value with a threshold value to judge a voltage drop event and trigger low voltage ride through control; dynamically calculating active and reactive power reference values through a reactive compensation equation and an active current limiting equation according to the voltage amplitude and the power reference value before falling during the ride-through period; inputting the active reference value into a virtual rotor motion equation to generate a reference phase, and outputting a phase reference signal in combination with a dual-mode phase compensation controller; superposing the reactive reference value with the reference voltage through a reactive voltage regulating ring to generate a voltage amplitude reference signal; synthesizing an internal potential according to the phase and the amplitude reference signal, and obtaining an inductive current reference value through virtual impedance control and current amplitude limiting; and finally, a driving signal is generated through the current inner loop controller and the modulation module. According to the invention, overcurrent can be effectively inhibited, rapid reactive power support is provided, and synchronous stability and smooth transition in a fault period and a recovery process are ensured.

The invention discloses a zero-sequence pilot-frequency excitation method for a double-circuit line in an incomplete power failure environment, which comprises the following steps of: applying zero-sequence pilot-frequency signal excitation on a power failure line by using a pilot-frequency power supply as an excitation signal source of a zero-sequence network of the double-circuit line, different-frequency induced current and voltage are measured at secondary sides of a current transformer and a voltage transformer at two sides of the operation line, and different-frequency zero-sequence voltage and different-frequency zero-sequence current in the double-circuit line zero-sequence network are obtained; simultaneously solving a zero-sequence network equation, and calculating mutual impedance between double circuits; performing frequency conversion to obtain the power frequency mutual impedance of the line; and finally, carrying out simulation verification by constructing a non-full-stop double-circuit line zero-sequence mutual inductance impedance measurement system. According to the method, the multi-path coupling caused by the existing power frequency interference method and the accuracy problem caused by the signal measurement error of the zero sequence increment method are solved, the test calculation can be accurately completed under the complex interference working condition, and the safety risk caused by the single-phase reclosing operation is avoided.

The invention provides an open-circuit fault diagnosis method for a three-phase interleaving three-level DC-DC converter, which comprises the following steps of: establishing a mathematical model of the three-phase interleaving three-level DC-DC converter by taking the sum of three-phase inductive current iL1 + iL4, iL2 + iL5 and iL3 + iL6 of inductive current iL1-iL6 of the three-phase interleaving three-level DC-DC converter as state variables; on the basis, designing an improved sliding-mode observer of the three-phase interleaving three-level DC-DC converter, and combining an observation value output by the improved sliding-mode observer with an actual value of the sum of inductive currents of upper and lower bridge arms of the same phase to construct a fault detection variable Mx (x = A, B and C) based on a residual gamma (t); a fault detection variable Nj based on the difference value between the inductive current iL1-iL6 and the current mean value is constructed by utilizing the characteristic that the corresponding inductive current declines at the fastest speed after the open-circuit fault of the switching tube, and j is equal to 1-6; and judging whether the corresponding switch tube has an open-circuit fault or not by comparing the two fault detection variables with a set threshold value.

The invention relates to a BUCK-BOOST converter control circuit, a control method and a safety air bag chip, the peak value of inductive current is detected through a current sampling compensation module, stable control of output voltage is achieved, the dynamic response speed is high, the loop stability is good, and meanwhile the circuit structure is simple. According to the BUCK-BOOST converter, stable switching of the working modes of the BUCK-BOOST converter is achieved through the mode control module, and it is ensured that the BUCK-BOOST converter can still work normally under the high voltage level. And the slope compensation unit is introduced into the circuit, so that subharmonic oscillation can be effectively prevented when the duty ratio of the PWM signal is greater than 50%, and the stability of the system is ensured.

The embodiment of the invention provides a closed-loop control method for power driving and protection, and the method comprises the steps: constructing a voltage feedback type circuit through a high-speed operational amplifier, and forming a closed-loop gain structure through a feedback network of the voltage feedback type circuit; the load current of the output end of the voltage feedback type circuit is monitored in real time, and when the load current exceeds a first set threshold value, a protection mechanism is triggered to turn off the output stage; the power-on surge current is limited through the soft start control circuit; phase information of a load reflection coefficient is obtained, an inductance / capacitance combination of the variable dynamic impedance matching network is selected according to phase information table look-up, inductance / capacitance parameters are switched through a relay, and the transmission standing-wave ratio between the power amplifier and a load is optimized; monitoring the temperature of the radiating fin of the power tube, and dynamically adjusting the resistance value of the feedback network; and performing cooperative control of short-circuit protection, over-temperature protection and surge suppression according to the priority. According to the embodiment of the invention, the performance bottleneck in a load fluctuation scene is broken through.

The invention discloses a single-stage bidirectional power conversion topological structure capable of realizing wide-range soft switching and a control method of the single-stage bidirectional power conversion topological structure. In-bridge and inter-bridge phase shift control of a double-half-bridge circuit and a high-frequency switch matrix provides a basis for realizing soft switching of all power tubes; the switching frequency is adjusted in real time according to the magnitude of the port voltage, soft switching within a wide voltage change range is achieved, the current of a bridge arm connected with the primary side of the second transformer is the sum of the primary side current of the second transformer and the current of an inductor connected in parallel with the second transformer, and the inductance value of the inductor connected in parallel with the primary side of the second transformer is designed. The current of the bridge arm connected with the primary side of the second transformer can be effectively changed, so that the soft switching implementation range of the switching tube of the bridge arm connected with the primary side of the second transformer in a wide power transmission range can be expanded.

According to the SiC MOSFET global short circuit and overcurrent protection circuit and the control method thereof provided by the invention, when a short circuit fault occurs in the SiC MOSFET, the drain current ID is more than several times of the rated current of the SiC MOSFET. When a short circuit occurs, a transistor QDZ of the short circuit detection circuit is switched on by node voltage Vr of the resistance-capacitance filter circuit, a fault signal VFAULT is converted into a low level, grid voltage VGS output by the grid control unit is gradually converted into zero voltage from negative driving voltage VEE, and soft turn-off is performed on the SiC MOSFET; when an over-current fault occurs in the SiC MOSFET, drain current ID is higher than rated current, node voltage Vo of the resistance-capacitance filter circuit lasts for a long time, the maximum value of capacitor voltage Vch of the over-current detection circuit is higher than reference voltage Vref2, a fault signal VFAULT is converted into low level, grid voltage VGS output by the grid control unit is gradually converted into zero voltage from negative driving voltage VEE, and soft turn-off is performed on the SiC MOSFET. According to the invention, high-speed short circuit and over-current fault protection of the SiC MOSFET in all inductance regions of a commutation loop can be realized.

The invention discloses a control method of a multi-module DAB converter. The control method comprises the following steps: S1, constructing a transmission power calculation model and a current stress calculation model of the DAB converter in an extended phase-shift control mode; s2, combining the two models through a Lagrangian function and then deriving, and determining a relational expression among a phase shift ratio, a voltage conversion ratio and transmission power of the DAB converter under the minimum current stress; s3, acquiring voltage and current information of the DAB converter, and calculating actual transmission power of each DAB module according to a direct power control method; and S4, solving the relational expression among the phase shift ratio, the voltage conversion ratio and the transmission power to obtain the optimal solution of the phase shift ratio of each DAB module, and sending the optimal solution of each phase shift ratio into an extended phase shift control circuit to realize control of each DAB module. While the power balance is realized, the inductive current stress is reduced, the system loss is reduced, and the overall operation efficiency is improved.

The invention discloses an ultra-low phase noise harmonic wave type four-core voltage-controlled oscillator. The ultra-low phase noise harmonic wave type four-core voltage-controlled oscillator is composed of a transformer T1, a transformer T2, a transformer T3, a transformer T4, a head oscillator HR1, a head oscillator HR2, a head oscillator HR3, a head oscillator HR4, a resistor R1, a resistor R2, a resistor R3, a resistor R4 and a plurality of decoupling capacitors Cecap. According to the voltage-controlled oscillator, noise is prevented from being converted into phase noise by means of second and third harmonic impedance broadening, inductance loss reduction, reduction of the sensitive time of the resonant cavity to the noise and the like, the phase noise generated by the voltage-controlled oscillator can be effectively reduced, and excellent noise performance is obtained.

The invention discloses a SiC MOSFET junction temperature monitoring circuit and monitoring method based on high-frequency oscillation suppression. The SiC MOSFET junction temperature monitoring circuit comprises a SiC MOSFET to be detected, a PCB mutual inductance coil, a high-frequency oscillation extraction unit, a grid adjustable driving unit and a junction temperature evaluation unit. According to the system, the oscillation time of the transient drain current of the SiC MOSFET switch is used as a temperature-sensitive electrical parameter to represent the junction temperature of the device, and the temperature sensitivity of the oscillation time can be improved by adjusting the grid amplifier to suppress high-frequency oscillation. According to the invention, the rapid detection of the junction temperature of the SiC MOSFET is realized, and the sensitivity of temperature-sensitive electrical parameters and the detection integration level are superior to those of a traditional junction temperature monitoring method.

The invention discloses a system and method for measuring the opening and closing state of an electromagnetic valve, and relates to the technical field of electromagnetic valves.The method comprises the steps that after an electromagnetic valve control signal is triggered, dynamic inductance L at each moment t is obtained through real-time backstepping by means of a voltage and current sampling module integrated in a driving loop and an inductance analysis module in a local microcontroller MCU; gaussian filtering processing and derivative calculation are carried out on the dynamic inductance L in the edge calculation module, first-order derivative and second-order derivative characteristics are extracted, and an inductance mutation factor index Cimp is obtained through calculation. According to the method, clamping stagnation, rebound and discontinuous abnormal states occurring in the opening and closing process of the electromagnetic valve are comprehensively reflected, a sudden change threshold value Cthr is set and compared, and a set of dynamic opening and closing behavior diagnosis mechanism with high resolution and high adaptability is constructed. According to the method, high-frequency dynamic response extraction and abnormal trend quantification can be completed within 100 ms after the control signal is triggered, and the method has higher early warning capability and non-intrusive compatibility.

The invention relates to a low-inductance SiC half-bridge power module layout structure based on overlapped copper bar conduction. Under the structure, the overlapped copper bars are used for replacing bonding wires in a traditional packaging structure, pits are machined in the copper bars to be connected with the power electrodes on the top face of the chip, the copper bars are bent to be connected with the substrate coated copper, and current conduction is achieved. Based on the overlapped copper bar structure, when the upper switch tube and the lower switch tube are switched on, mutual inductance and mutual suppression exist between current paths on the lower conductive copper bar and the upper conductive copper bar, and the module has low parasitic inductance; two ends of the upper-layer copper bar and the lower-layer copper bar are fixedly connected with the substrate, and the middle positions of the upper-layer copper bar and the lower-layer copper bar are fixedly connected with a chip top surface electrode, so that the module reliability is high; the thicknesses of the upper and lower copper bars are adjustable to ensure the through-current capability of the module; the copper bar is low in processing cost, does not need a cushion block, and reduces the number of connection interfaces. Therefore, compared with the existing layout packaging structure, the module layout structure provided by the invention has outstanding advantages in the aspects of parasitic inductance, outflow capacity and cost, and is suitable for popularization and application.

A control system for an AC-DC converter includes a mixed-signal power controller and first and second gate drivers. The controller has a digital module and an analog module. The analog module has a current sensor generating a current sense voltage based on a sensed switch current. The digital module has a DC voltage sensor generating a DC sense voltage based on a DC bus voltage, and an AC voltage sensor generating an AC sense voltage and a binary polarity signal based on the AC voltage. The digital module induces the first gate driver to output first and second control signals for controlling a high-side switch and a low-side switch of a current shaping half-bridge based on first and second clock signals and the comparator voltage, such that an inductor current flowing through an inductor is proportional to a current command value.

The invention provides an ultrasonic transceiving device and a control method thereof. The ultrasonic wave transmitting and receiving device comprises a plurality of coupled ultrasonic wave transmitting and receiving units. Each ultrasonic wave transceiving unit comprises a plurality of ultrasonic wave oscillators; the driving bias circuit is coupled to the plurality of ultrasonic oscillators, and the driving bias circuit is used for receiving alternating current voltage; and a switching circuit coupled to the driving bias circuit, the switching circuit having a plurality of switching paths, the plurality of switching paths corresponding to a plurality of impedance values or a plurality of inductance values, the switching circuit is used for switching a system driving signal to pass through one of the switching paths according to a mode selection signal to serve as the alternating voltage and transmitting the alternating voltage to the driving bias circuit.

The invention relates to the technical field of servo control, in particular to a high-precision current closed-loop control system and method for a servo driver, and the method comprises the steps: collecting three-phase current, rotor position, winding temperature and bus voltage, and constructing a state data set; constructing a parameter identification model fusing physical prior and an attention mechanism, deducing inductance and flux linkage parameters influenced by temperature, saturation and cross coupling, and correcting a motor model in real time; the correction parameters are injected into an FOC decoupling and feedforward link, and a self-adaptive PI regulator is linked to set the gain of a current loop on line; calculating a d-q axis voltage command according to the update model to respectively control excitation and torque components; an extended state observer is introduced to estimate load abrupt change and parameter disturbance, feed-forward compensation is carried out, and three-phase PWM is generated through anti-Parker and SVPWM; and an inverter nonlinear compensation model of a dead zone and switch delay is constructed, PWM is pre-distorted and output to a power device, and robust and low-ripple current closed-loop control of the servo motor is realized.

The embodiment of the invention discloses a voltage conversion circuit and a switching power supply. A control module magnetizes or demagnetizes an inductor by controlling alternate conduction of a main switching tube and a follow current switching tube in a voltage conversion module, and charges and discharges a first capacitor. A virtual inductive current ripple signal is constructed through a virtual ripple generation module, and the virtual inductive current ripple signal replaces ESR information on a first capacitor to be superposed on a feedback voltage, so that after the feedback voltage is superposed with the virtual inductive current ripple signal, the phase difference between the feedback voltage and an inductive current is reduced, and the feedback voltage is reduced. The control module outputs a first control signal according to a virtual inductive current ripple signal and a feedback voltage to control the conduction time of the main switching tube and the follow current switching tube, so that the problem of harmonic oscillation caused by a time-lag effect between an inductive current and the output voltage on the first capacitor is solved, and the generation of harmonic waves is suppressed; the stability of the output voltage of the voltage conversion circuit is improved.