31 results about "Total harmonic distortion" patented technology

An audio input circuit capable of avoiding the deterioration of total harmonic distortion (THD) includes a single-ended signal input circuit, a differential signal input circuit, a first amplifier circuit and a second amplifier circuit. The single-ended signal input circuit is enabled by a switch in a single-ended mode to output a single-ended audio signal to the first amplifier circuit. The differential signal input circuit is enabled by a switch in a differential mode to output a differential audio signal to the first amplifier circuit. The first amplifier circuit outputs an inverted audio output signal to the second amplifier circuit according to the signal received thereby. The second amplifier circuit outputs a non-inverted audio output signal according to the signal received thereby. In the single-ended and differential modes, the signals input to the non-inverted input terminals of the first and second amplifier circuits are DC signals to stabilize the on-resistance linearity of the switches in the audio input circuit and to avoid the deterioration of THD of the audio input circuit.

The application relates to a compressor valve piece fault monitoring method and device, which is applied to the technical field of compressor intelligent operation and maintenance and fault diagnosis, and comprises the following steps: collecting a compressor exhaust pressure pulsation signal, a motor three-phase current signal and a compressor shell vibration signal; performing feature extraction on the compressor exhaust pressure pulsation signal to obtain a modulation sideband amplitude value ratio in an envelope spectrum with a compressor real-time operation frequency as the center; performing feature extraction on the motor three-phase current signal to obtain a current total harmonic distortion rate; performing feature extraction on the compressor shell vibration signal to obtain a preset frequency band root mean square value; performing graded fault judgment according to the modulation sideband amplitude value ratio, the current total harmonic distortion rate, the preset frequency band root mean square value and judgment logic to determine a fault judgment result; and performing graded early warning based on the fault judgment result. The application has the effect of timely and accurate identification of early compressor valve piece faults.

This invention discloses a grain depot equipment operation status monitoring and green energy-saving control system, belonging to the field of intelligent grain depot control technology. It collects the instantaneous output frequency and total harmonic distortion (THD) of the variable frequency drive equipment, and simultaneously separates high-frequency noise components higher than the grain temperature change frequency. Based on the output frequency, it determines whether it falls into a sensitive frequency band, and performs causal correlation analysis between the high-frequency noise energy spectrum and the THD to calculate a reliability index. When the reliability exceeds a threshold, it determines that the temperature sampling value is contaminated by harmonics, discards the value, and generates a repaired temperature value based on the heat diffusion law of the grain pile using time-domain prediction or spatial interpolation. The repaired value is used for energy-saving control drive; when a temperature jump and an energy-saving control action are detected to be inversely related, the start / stop command of the variable frequency drive equipment is forcibly blocked. This invention, by identifying and suppressing harmonic interference from the variable frequency drive, avoids reverse control caused by temperature data jumps, ensuring the safety and reliability of energy-saving operation of the grain depot.

An audio input circuit includes a single-ended signal input circuit, a differential signal input circuit, a first amplifier circuit, and a second amplifier circuit. The single-ended signal input circuit is enabled by switches in a single-ended mode to output a single-ended audio signal to the first amplifier circuit. The differential signal input circuit is enabled by switches in a differential mode to output a differential audio signal to the first amplifier circuit. The first amplifier circuit outputs an inverted audio output signal to the second amplifier circuit according to signals it received. The second amplifier circuit outputs a non-inverted audio output signal according to signals it received. In the single-ended and differential modes, the signals inputted to non-inverting inputs of the first and second amplifier circuits are DC signals to stabilize the on-resistance linearity of the switches and prevent the deterioration of the audio input circuit's total harmonic distortion.

The application discloses a single-stage isolated inverter control method based on variable frequency and extended phase-shift modulation. The method comprises the following steps: sampling and acquiring input and output voltage and current of the converter and preset parameters; calculating real-time power and comparing the real-time power with a preset threshold to determine a heavy-load constant-frequency or light-load variable-frequency working mode; calculating a switching frequency, a theoretical inner phase-shift angle and an outer phase-shift angle based on the mode, and maintaining an effective phase-shift angle through variable frequency to ensure a zero-voltage turn-on range when the light load; predicting a switching tube turn-off current by using an analytical model; judging a switching state according to the predicted current, calculating a dead-time compensation correction quantity adaptive to the switching frequency variation, correcting the theoretical phase-shift angle, and obtaining a final control quantity. The application realizes high efficiency and soft-switching operation in a full power range by combining light-load variable frequency control with extended phase-shift modulation, and significantly improves the output current waveform quality and reduces total harmonic distortion through frequency-adaptive accurate dead-time compensation.

This invention relates to a Kalman filter active damping iterative learning model predictive control method for grid-connected inverters. First, by using only measured signals of inverter-side current and grid-side voltage through a Kalman filter, the state variables of the LCL filter are estimated in real time, replacing physical sensors and reducing hardware costs. Second, based on the estimated capacitor voltage, the active damping current is calculated, and a composite current reference value for the inverter side is generated to actively suppress resonance. Then, an iterative learning control outer loop is introduced to compensate for periodic disturbances such as dead-zone effects, generating a compensation current using historical error data to improve current quality. Finally, finite set model predictive control is used to optimize the switching state, achieving high-precision tracking. This invention reduces the number of sensors, enhances anti-interference capability and robustness, and significantly reduces the total harmonic distortion of the output current. It is suitable for distributed renewable energy generation systems, ensuring the stable and efficient operation of grid-connected inverters.

The application provides a power distribution box power quality optimization method and device, and belongs to the technical field of smart grids. The method comprises the following steps: determining three-phase electrical effective value data based on three-phase electrical sampling data at the outlet of a smart grid terminal power distribution box; determining a power factor, a load change rate, a total harmonic distortion rate and a three-phase imbalance degree based on the three-phase electrical effective value data; determining an electric power quality disturbance grade type based on the total harmonic distortion rate, the three-phase imbalance degree and the power factor; determining a power distribution box operation scene type based on the load change rate, wherein the operation scene type is a steady-state scene or a transient mutation scene; determining the governance weight of a plurality of governance components based on the electric power quality disturbance grade type, determining a hierarchical governance instruction based on the governance weight of the plurality of governance components; and generating a scene-adaptive governance instruction based on the hierarchical governance instruction and the operation scene type. The application can realize hierarchical and accurate governance of power distribution box power quality disturbances and adapt to the development needs of smart grids.

This invention discloses a method and apparatus for common-mode voltage elimination and current ripple minimization in a three-level inverter. Addressing the problem of significantly increased total harmonic distortion (THD) of phase current in traditional common-mode voltage elimination (CMVE) methods, this invention explores all feasible PWM sequences for achieving CMVE, deriving the optimal PWM sequence for each modulation ratio and voltage vector angle. The concept of harmonic flux linkage error is used to quantitatively evaluate the current ripple generated by each sequence within one switching cycle. The significant impact of the initial switching instant on the effective value of harmonic flux linkage error for the same PWM sequence is revealed. Based on the optimal PWM sequence and optimal delay time, a final mirror-symmetric PWM sequence is obtained after phase shifting, and applied to a dual three-phase three-level inverter. This invention can significantly reduce the THD of phase current while eliminating common-mode voltage, maintaining the motor's output performance.

The application discloses a power distribution network evolution mode division method considering voltage out-of-limit and harmonic over-limit, and belongs to the technical field of intelligent power grid operation management and control, and comprises the following steps: constructing a multi-resource grid connection scene of multiple flexible resources of a power distribution network; performing power flow calculation and harmonic power flow calculation on the multi-resource grid connection scene, acquiring voltage amplitude, voltage harmonic content and voltage total harmonic distortion rate of each node at different time sections, and constructing a power distribution network voltage out-of-limit matrix and a power distribution network harmonic over-limit matrix; based on the power distribution network voltage out-of-limit matrix, performing primary division on the multi-resource grid connection scene by using a density clustering DBSCAN algorithm, and based on the primary division result, performing secondary division on the multi-resource grid connection scene by using the DBSCAN algorithm according to the power distribution network harmonic over-limit matrix. The method fully reflects the complexity and quality constraint of the operation state in the mode division process, and the result is more comprehensive and more in line with the actual operation characteristics.

The application discloses a method for adaptively adjusting SOGI damping coefficient based on power grid THD, which comprises the following steps: S1: collecting three-phase power grid voltage to obtain two-phase voltage signals and; S2: calculating total harmonic distortion rate of current power grid voltage; S3: based on the value of the total harmonic distortion rate, SOGI damping coefficient k; S4: inputting the dynamically determined SOGI damping coefficient k into two SOGI operation units for processing the two-phase voltage signals and respectively to generate two orthogonal signals and; S5: using the orthogonal signals and output by the SOGI operation unit for subsequent control, and the orthogonal signals and are used for constructing virtual orthogonal signals to realize phase locking or positive and negative sequence separation. The application establishes a closed-loop dynamic mapping relationship between power grid total harmonic distortion rate THD and adaptively adjusted SOGI damping coefficient k.

The application discloses a high-torque-density double-rotor permanent magnet fault-tolerant motor and a pole arc coefficient optimization method thereof, and comprises coaxially arranged inner rotor, stator and outer rotor; the axial end portions of the outer rotor and the inner rotor are fixedly connected, the stator is arranged between the inner rotor and the outer rotor and forms inner-layer air gaps and outer-layer air gaps with the inner rotor and the outer rotor respectively; the inner rotor and the outer rotor are both provided with Halbach arrays; the pole arc coefficient of the Halbach array is determined through an electromagnetic performance prediction model based on HO-GRNN and a pole arc coefficient optimization method of an improved sacred religion algorithm, the sum of the inner-layer air gap and the outer-layer air gap magnetic flux density fundamental wave amplitude is maximized, and the total harmonic distortion rate is minimized; and when the motor operates, the winding magnetic field simultaneously acts on the inner-layer air gap and the outer-layer air gap, and respectively interacts with the permanent magnet magnetic field of the inner rotor and the outer rotor, and the outer rotor and the inner rotor superimpose and output total torque.

A power tools includes a battery pack interface configured to receive a removable and rechargeable battery pack and a motor. The motor includes a rotor and a stator. The rotor includes a plurality of magnets and a rotor outer surface. The outer rotor surface includes a plurality of notches. Each of the plurality of notches is positioned between adjacent magnets of the plurality of magnets. The stator includes a plurality of stator teeth configured to receive a plurality of stator windings. Each of the plurality of stator teeth includes a plurality of peaks and valleys that extend around the rotor outer surface. Each peak extends axially inward in a radial direction of the rotor, and each valley extends axially outward in the radial direction of the rotor.

The present application belongs to the technical field of low-voltage reactive power compensation. A method for identifying harmonic risk and inhibiting misoperation of an intelligent metal comprehensive distribution box is disclosed. First, the present application collects harmonic-related operating state information and constructs a harmonic risk feature vector. Then, a light gradient boosting classification model is used to estimate the basic risk probability of future short-term harmonic risk. Next, the harmonic level is corrected at the combination level according to the basic risk probability and the current total harmonic distortion rate, combined with the equivalent compensation capacity of the candidate compensation combination, to generate a set of allowed branches. Finally, the comprehensive control cost is calculated in the allowed set, and the combination with the minimum cost is selected to execute the switching. The present application jointly uses the future harmonic risk probability, the candidate combination harmonic level estimate, the zero sequence current, the branch health state and the compensation capacity for switching decision, which can effectively reduce the number of harmonic over-limit windows and the number of misoperation actions, and can balance the inhibition effect and compensation performance under harmonic pollution conditions.

The application relates to the technical field of oscilloscopes, in particular to a digital oscilloscope circuit and control method based on LVGL, which comprises a front-stage signal conditioning circuit, an analog-digital conversion circuit, a main control circuit and a display module; wherein the front-stage signal conditioning circuit, the analog-digital conversion circuit, the main control circuit and the display module are electrically connected; the front-stage signal conditioning circuit attenuates and biases input signals; the main control circuit analyzes sampling data in time domain and frequency domain; total harmonic distortion is calculated by frequency domain analysis; range control is carried out; and the front-stage signal conditioning circuit is controlled by signal amplitude trend. The application solves the problems of waveform tearing, ghosting and FFT spectrum pseudo-peak on the screen during range switching of the existing oscilloscope.

The application discloses a kind of multi-scene equipment communication methods and electric energy meter based on intelligent internet of things electric energy meter, it is related to electric energy meter communication technical field, comprising: obtaining voltage sampling sequence and current sampling sequence, according to signal zero crossing and disturbance event starting point determine phase anchor point, and combine event register and measurement state to determine scene number;With phase anchor point as center, extract integer fundamental period window, calculate voltage total harmonic distortion, current total harmonic distortion, harmonic amplitude and equivalent impedance amplitude, generate measurement fingerprint, and combine table in counter derived time slot seed;According to scene number configuration time slot length and maximum waiting time delay, based on measurement fingerprint and time slot seed, determine sending time slot and sending time, and after combining bearing state table selects main communication bearing and standby communication bearing, send message, and based on receipt check switch retransmission, to improve time slot determination accuracy, sending real-time and communication stability.

The application provides a control method and device of a doubly-fed induction motor, electronic equipment and a storage medium, and is suitable for the technical field of motor control. The method comprises the following steps: acquiring a plurality of basic voltage vectors of a back-to-back three-level neutral point clamped converter; determining a machine-side pulse width modulation signal based on a machine-side double-vector prediction model and the basic voltage vectors; determining a grid-side first voltage vector and a grid-side second voltage vector from the basic voltage vectors by using a grid-side double-vector prediction model; constructing a symmetrical switching pulse sequence based on the grid-side first voltage vector and the grid-side second voltage vector to generate a grid-side pulse width modulation signal; and outputting the machine-side pulse width modulation signal and the grid-side pulse width modulation signal to a machine-side converter and a grid-side converter respectively. The grid-side pulse width modulation signal of the application adopts a symmetrical switching pulse sequence wave generation mechanism, suppresses even harmonics in a switching period, and reduces the total harmonic distortion of the grid-connected current.

This invention relates to the field of power system relay protection technology and discloses an adaptive relay protection threshold setting method for high-proportion distributed photovoltaic distribution networks, comprising the following steps: S1: The end-side protection device collects electrical signals of the protected line and extracts the current transient change rate di / dt and the negative sequence current change amount ΔI2 as mixed fault characteristic quantities; This adaptive relay protection threshold setting method for high-proportion distributed photovoltaic distribution networks extracts the current transient change rate and the negative sequence current change amount as mixed fault characteristic quantities through the end-side protection device, and calculates the dynamic current protection threshold by combining the inverter current limiting value, low voltage ride-through state, real-time output of distributed photovoltaic, system short-circuit capacity, total harmonic distortion rate of voltage, line rated current and maximum load current, so that the protection threshold can be adjusted according to the fault characteristics, photovoltaic penetration state and inverter current limiting capability, thereby improving the adaptability of relay protection threshold setting in high-proportion distributed photovoltaic access scenarios.

The application provides an improved method and device for a variable reluctance resolver based on a reluctance sinusoidal rotor, and belongs to the technical field of variable reluctance resolvers. The method comprises the following steps: obtaining an air gap permeance waveform of the reluctance sinusoidal rotor; determining an output cosine envelope waveform of the reluctance sinusoidal rotor according to the air gap permeance waveform and a unit cosine envelope waveform; determining a target harmonic component with the largest total harmonic distortion contribution to the output cosine envelope waveform according to the output cosine envelope waveform; and determining a target stator tooth width of the variable reluctance resolver by using a finite element simulation method, with the amplitude of the target harmonic component being the smallest as the target. The improved method and device for the variable reluctance resolver based on the reluctance sinusoidal rotor can determine the rotor configuration of the reluctance sinusoidal rotor and the stator tooth width of the variable reluctance resolver, so as to improve the variable reluctance resolver based on the reluctance sinusoidal rotor and obtain a smaller THD.

This utility model relates to the field of chip packaging technology, and more particularly to a packaging structure for reducing the total harmonic distortion (THD) of MEMS piezoacoustic devices. The structure includes: a substrate having a hollowed-out cavity, a limiting device, and multiple vent holes at the bottom; and a MEMS sound-emitting chip, inverted and soldered onto the substrate, with its edge region bonded to the substrate via a connection point to form a first acoustic cavity. This utility model provides a packaging structure for reducing the THD of MEMS piezoacoustic devices. The inverted soldering of the MEMS sound-emitting chip effectively reduces the volume while ensuring packaging stability. The diaphragm of the MEMS sound-emitting chip and the substrate form the first acoustic cavity, while the chip, substrate, and shell together form a second acoustic cavity. Through dual-cavity air pressure balance, mechanical limiting, and acoustic path optimization, nonlinear vibration is reduced, significantly lowering the total harmonic distortion (THD) of the MEMS piezoacoustic device and improving sound radiation efficiency.

This invention relates to the field of power monitoring technology, specifically to an intelligent fusion terminal integrating circuit breaker condition monitoring and adaptive control. It obtains the load harmonic coupling coefficient at any given time based on the correlation characteristics of changes in active power and total harmonic distortion rate within preset adjacent time periods. The coupling coefficient sequence is decomposed using STL time series decomposition to obtain a trend term and a residual term. Based on the difference between the trend term and the predicted trend value at any given time, and the residual term, a health deviation index is obtained. The rate of change is obtained based on the changing characteristics of the health deviation index. The future health deviation index for the next time moment is obtained based on the rate of change and the current health deviation index. This invention obtains a safe duration based on a preset health deviation index threshold, the current health deviation index, and the rate of change. It monitors and controls the circuit based on the future health deviation index and the safe duration, improving power supply reliability, early warning, and the accuracy of control.

Technologies are described for a light emitting diode (LED) driver configured for powering LED(s) and having a wide input voltage range between about 100V and about 528V, high power factor, low total harmonic distortion (THD), and low output current ripple load. The LED driver has a single stage buck-boost type converter with output current regulation, an output current regulation circuit, a ripple control circuit having a transient voltage suppressor (TVS) and a parallel resonant LC filter, a power factor correction (PFC) control circuit having a digital compensation block, a PFC controller, and a gate drive IC.

This invention belongs to the field of power quality measurement technology, specifically disclosing a harmonic measurement and evaluation method and system based on time-domain statistics. The method includes: acquiring the time-domain waveform signal of the power signal containing harmonic information for each sliding window; calculating the single-window harmonic energy variance index using statistical calculation methods; grouping the discretized single-window harmonic energy variance index according to the required frequency resolution; determining whether each group of data exhibits a centrally symmetrical distribution within acceptable error limits; if so, calculating the harmonic energy variance index for harmonic distortion evaluation with a preset period length; and establishing the correspondence between the harmonic energy variance index and the total harmonic distortion rate index, thereby intuitively evaluating the harmonic distortion of the power system. This invention enables lightweight data calculation, improves data processing efficiency, and can meet the needs of online monitoring to a certain extent.

This invention discloses a diesel generator parallel operation management system and power switching control method, belonging to the field of power system automation technology. It collects voltage, current, phase difference, and active and reactive power data from the power grid, diesel generator, and parallel operation system; it also collects test load temperature, personnel intrusion data from the work area, and power grid reactive power demand data. An improved FFT spectrum analysis algorithm is used to process the voltage and current signals to calculate the total harmonic distortion (THD). An improved coordinate partitioning method is used to obtain the phase sequence components, and the three-phase imbalance value is calculated based on these components. This invention combines diesel generator parallel operation power switching with test load air intake control and personnel safety monitoring, achieving automatic opening and closing of the air intake damper and graded alarm linkage for personnel intrusion. This reduces manual intervention and lowers operational safety hazards. Simultaneously, a closed-loop correction mechanism dynamically adjusts compensation parameters and switching timing to ensure the stability of power output during power switching.

This invention provides a harmonic suppression method for a T-type three-level inverter using active reconfiguration of switch combinations, relating to the field of power electronics technology. Addressing the shortcomings of existing methods that rely on precise modeling and have poor dynamic adaptability, this method acquires the three-phase output voltage in real time and extracts the harmonic deviation vector. Based on its direction angle, a lookup table is used to select the corresponding switch combination as the modulation mode. The drive pulses of the selected switches are actively shielded to change the available set of the basic voltage vector. A linear equation system for the modulation time correction is established, and the SVPWM modulation time is reconstructed. A compensation voltage opposite to the original harmonic deviation is synthesized, and this process is iterated in a closed loop until the harmonic deviation is below a threshold. This method does not change the main circuit, does not rely on precise mathematical models, and does not affect the fundamental frequency control. It achieves directional harmonic cancellation through dynamic reconfiguration of switch combinations, effectively reducing the total harmonic distortion rate and adapting to high power quality scenarios such as motor drives and new energy grid integration.

The application discloses an active control method for suppressing secondary ripples on the DC side of a two-stage inverter, and relates to the technical field of new energy power generation. The core characteristic parameters of the secondary ripples on the DC side are accurately and timely captured by a ripple detection module, a dynamic compensation current instruction with opposite phase and matched amplitude is generated by combining a compensation signal generation module, and the dynamic compensation current instruction is superimposed on a current inner loop reference signal through a front-stage DC-DC converter control module, so that the secondary ripples on the DC side are effectively offset, compared with a traditional passive filtering scheme, no additional bulky filtering elements are needed, the system size and cost are reduced, and a higher ripple suppression rate is achieved; a rear-stage inverter coordination module can dynamically respond to the front-stage compensation action, the spectral characteristics of a modulation wave are optimized, the total harmonic distortion rate of the output power on the AC side is ensured to be maintained at a low level, the front-stage module and the rear-stage module are cooperatively worked, and the ripple suppression effect and the power quality are considered.

This invention discloses and provides a low-cost, simple-structured totem-pole PFC power supply circuit and its control method for wireless charging systems, which can reduce total harmonic distortion and improve the performance of wireless charging systems. The bridgeless totem-pole PFC power supply circuit for wireless charging systems in this invention includes an AC power supply V... ac The components include inductors Lm1 and Lm2, a first high-speed power bridge arm, a second high-speed power bridge arm, a slow-speed rectifier bridge arm, an output filter capacitor C, a load resistor R, and a voltage output V. This invention is applicable to the field of power electronics technology.

A voltage controller detects a voltage spike in an electrical signal received from an electrical power source. The voltage controller is implemented using a single-loop control system in a stationary reference frame. The electrical signal includes voltage harmonics caused by a non-linear or unbalanced load. The voltage controller includes a phase-compensated harmonic regulator that regulates the voltage harmonics present in the electrical signal and receives a feedback voltage of the single-loop control system. The feedback voltage is a delayed version of an instantaneous voltage of the electrical signal. The instantaneous voltage is sub-transiently stabilized into a steady-state voltage based on the feedback voltage. Sub-transiently stabilizing the instantaneous voltage is performed within a single cycle after the voltage spike is detected. The steady-state voltage has a total harmonic distortion less than a threshold total harmonic distortion and the steady-state voltage has a balanced sinusoidal waveform.

This invention discloses a performance testing method and system for power amplifier boards, relating to the field of power amplifier board testing technology. Its main technical solution involves configuring the amplitude weights of each fundamental frequency component in a multi-tone test signal according to the small-signal gain, and then inputting the configured multi-tone test signal into the power amplifier board under test. An adaptive flatness adjustment mechanism is employed to reduce the workload of manually reconfiguring signals due to batch differences or uneven frequency response of the power amplifier boards. This aims to improve the automation and repeatability of the testing process. Simultaneously, the impedance value of the programmable electronic load connected to the power amplifier board under test is adjusted to obtain corrected efficiency curves and total harmonic distortion (THD) curves under different impedance values. By scanning the programmable electronic load, the variation of the efficiency and distortion curves with load impedance is obtained. This aims to identify the optimal load matching of the power amplifier board and the regions prone to mismatch failure.

The application relates to the technical field of inverters, and particularly discloses a single-tube inverter with full-wave output, a wireless power transmission system and a control method thereof. The inverter has the characteristics of simple circuit structure, simple driving circuit, only one NMOS tube, resonant state irrelevant to a load, etc. The main switch can be effectively opened at zero voltage from a wide load resistance range from a rated load to a short circuit, the system output voltage is approximately a sine wave, the total harmonic distortion of the system current is very small, and the inverter can be widely applied to various fields of high-frequency inversion. The wireless power transmission system adopts the above inverter at a transmitting end, is coupled to a receiving end through a wireless power transmission coupling mechanism, adopts a series capacitance compensation mode for a compensation network, realizes stable constant voltage output of the system, and effectively realizes zero voltage opening of a power NMOS tube. The system circuit structure is simple, the reactive power is small, the transmission efficiency is high, and the system has the best transmission effect in a wide load resistance range from a rated load to a short circuit.

This invention relates to the field of switching power supply technology and discloses a single-stage resonant AC-DC converter device with an integrated Buck-boost unit. The device includes a single-stage resonant AC-DC converter with an integrated Buck-boost unit and a control circuit. It solves the technical problems of existing AC-DC converters, such as complex two-stage structures, large single-stage resonant cavity current, low power factor, and high total harmonic distortion. The single-stage resonant AC-DC converter with an integrated Buck-boost unit includes a filter, an input rectifier, and a filter capacitor C. in First switch arm, second switch arm, capacitor C b Inductor L b Resonant inductor L r and resonant capacitor C r The components include a resonant cavity, a transformer T, an output rectifier, and an output capacitor C. o This invention eliminates energy backflow, achieving low resonant cavity current, high power factor, and low THD. Furthermore, it features a small frequency variation range for the switching transistor, facilitates soft switching, and simplifies the structure. It can be applied to data center server power supplies, vehicle chargers, power adapters, and other fields, demonstrating significant engineering application value.