381 results about "Voltage limit" patented technology

The invention relates to the technical field of intelligent power grids, and provides an intelligent operation centralized control center intelligent scheduling interaction method and system, and the method comprises the steps: generating a heat distribution gradient through environment noise filtering, reflecting the temperature field change of equipment, obtaining a voltage amplitude envelope through fundamental wave and harmonic wave separation, and monitoring the power quality; a current fluctuation coefficient is extracted by combining segmented deviation analysis to evaluate a line load state, and frequency fluctuation parameters are captured by using time domain statistics to track system stability. By constructing a dynamic association map, heterogeneous data such as thermodynamics, electrical quantity, load characteristics and synchronous states are mapped to power grid topological nodes, and a cross-dimension association relationship is established to realize whole-network state coupling analysis. An overload risk, a voltage out-of-limit probability and a system instability threshold are quantified through a hierarchical evaluation mechanism, a multi-target optimization constraint condition is formed, and finally a scheduling strategy considering equipment safety, economy and power supply reliability is generated. When the power system operates, intelligent scheduling is carried out according to the operation state of the power grid.

The invention relates to the technical field of automatic control, and discloses a PID (Proportion Integration Differentiation) intelligent pressure reducer controller, which comprises the following steps of: judging whether an environment disturbance or a load sudden change event exists according to a system load change rate and sensor feedback stability, constructing a master control-controlled coupling characteristic matrix by adopting a dual-channel data fusion method, performing attribution splitting on each disturbance channel, and obtaining a PID (Proportion Integration Differentiation) intelligent pressure reducer. PID parameters are dynamically adjusted according to the principal component weight of a disturbance channel, a variable parameter PID adjustment matrix is constructed, filtering smoothing is carried out on sampled signals through an extended Kalman filtering algorithm, a feedback closed-loop correction vector based on sampling residual errors is constructed, a historical offset tracking and switching value boundary judgment mechanism is introduced, fine tuning suppression is carried out on control signals of a motor driving mechanism, and the control signals of the motor driving mechanism are output. Judging whether a mechanical limiting protection device needs to be activated or not; and if yes, automatically triggering voltage limiting protection logic and locking the current control quantity. The method has the advantage of improving efficient and stable operation.

The invention discloses a voltage out-of-limit control method and system for grid connection of a photovoltaic power generation system containing energy storage, and the method comprises the steps: building a grid connection model according to an equivalent structure diagram of grid connection of the photovoltaic power generation system containing energy storage; according to the grid-connected model, under the conditions that the line impedance is fixed and the load power is random and uncontrollable, the voltage of a grid-connected point is adjusted by controlling active power and reactive power output by an inverter; a dynamic participation factor is introduced, and the charge state of energy storage and the residual capacity of an inverter are taken into reference so as to carry out self-adaptive distribution of power. The method can effectively solve the problems of insufficient adjustment and response lag of a current power distribution network voltage out-of-limit control strategy.

The invention discloses an MPC-SP-based all-vanadium redox flow battery constant-power charging and discharging control method, which is applied to an energy storage control system composed of an MPC-SP controller, a PCS and an all-vanadium redox flow battery, and is characterized in that the controller dynamically and accurately adjusts the power output to the battery based on preset SOC interval division, and the power output to the battery is increased along with the increase of the actual SOC value of the battery. The power is increased in stages. Meanwhile, the controller pays attention to the voltage Ud of the battery end all the time, and when the Ud reaches a voltage limiting value, the constant voltage mode is switched, so that the battery is effectively prevented from being damaged due to overhigh voltage. The state-based dynamic power management is much safer, more flexible and more intelligent than traditional fixed constant power control. According to the invention, the change rate of current in the charge-discharge process of the all-vanadium redox flow battery can be reduced, the service life of the battery is prolonged, and the safety is guaranteed.

The invention relates to the technical field of welding, and provides a low-load voltage circuit and a lithium battery welding machine. The circuit comprises a main control module, a voltage detection unit, a switching circuit, a pulse modulation unit and a current sampling feedback unit. The voltage detection unit monitors the end voltage of a welding gun of a welding machine in real time, the switching circuit limits the output voltage to be smaller than a safety threshold value of 36 V in a no-load mode, and a built-in bidirectional thyristor achieves isolation of a high-voltage loop and a low-voltage loop. The pulse modulation unit adjusts the on-off frequency of a main power loop, and the current sampling feedback unit dynamically adjusts the pulse duty ratio so as to accurately control the welding current. The lithium battery welding machine integrates the circuit and is provided with a welding gun assembly, a main transformer and a power supply module, the electric shock risk is effectively reduced, and the welding quality and efficiency are improved.

An adapter for introduction into a two-conductor line comprises an adapter housing; and, arranged in the adapter housing, an adapter electronics that connects a first terminal with a third terminal using a first connecting line and a second terminal with a fourth terminal using a second connecting line, wherein the adapter electronics further includes an overvoltage protection system designed to limit a voltage applied across the third and fourth terminals to a first maximum value in the event of failure; an overcurrent protection system adapted to prevent a rise of the loop current above a maximum electrical current value in the event of failure; and a circuit adapted in the non-failure case to control a voltage applied to the overvoltage protection system, from a minimum input voltage, to a second maximum value lower than the first maximum value.

The invention provides a data center micro power supply capacity optimization method and system. The method comprises the following steps: constructing a corresponding three-dimensional constraint parameter group in real time according to real-time working parameters; obtaining a first correlation coefficient between the power balance parameter and the equipment capacity parameter through linear correlation, obtaining a second correlation coefficient between the equipment capacity parameter and the voltage limiting parameter through nonlinear correlation, and obtaining a third correlation coefficient between the voltage limiting parameter and the power balance parameter through mapping correlation; obtaining a power output predicted value of the photovoltaic micro-grid, and constructing a corresponding capacity optimization function in real time in combination with the first correlation coefficient, the second correlation coefficient and the third correlation coefficient; and performing optimization processing on a preset particle swarm algorithm to generate a corresponding target optimization algorithm, and solving the capacity optimization function through the target optimization algorithm to output a corresponding photovoltaic capacity optimization value in real time. According to the method, the capacity of the photovoltaic micro power supply can be objectively and dynamically optimized, and the optimization efficiency is improved.

The invention discloses a field weakening control method and device of a motor, a storage medium and a vehicle, and the method comprises the steps: determining and inputting an electrical parameter corresponding to a given reference torque of the motor to the motor based on a pre-established current lookup table; when the output voltage of a current controller of the motor exceeds the output voltage limit of an inverter of the motor, determining corresponding motor parameters based on the electrical parameters obtained through real-time monitoring and a pre-established motor parameter lookup table; determining a target included angle based on the electrical parameters and the motor parameters; determining a weak magnetic area where the motor is located based on the target included angle; and based on the weak magnetic area where the motor is located, determining a corresponding electrical parameter correction value, and correcting the electrical parameter to control the output torque of the motor. According to the method, the electrical parameters can be effectively corrected based on the change of the motor parameters, the torque can be accurately output in the flux-weakening acceleration process of the motor, and the torque control precision of the motor under the flux-weakening working condition is improved.

A method and system for protecting a battery power limit, and a storage medium are disclosed. The method for protecting a battery power limit is applied to a vehicle with a battery management system. The method includes: acquiring temperature data, a state of charge, and a cell voltage extreme value of a battery, periodically; calculating a current maximum available power according to the temperature data and the state of charge; determining a power limit coefficient according to the cell voltage extreme value, and a voltage limited power interval corresponding to the temperature data; and obtaining an actual available power that the battery management system allows the vehicle to use according to the maximum available power and the power limit coefficient. According to the method, different temperature ranges can be adapted according to logic.

The invention belongs to the technical field of impact current suppression, and relates to a method and system for suppressing the impact current of a DC bus output by a DC charger, and the method comprises the following steps: collecting the output voltage of the DC bus and the required voltage of a vehicle side, and forming a voltage sequence; calculating the change rate and the pressure difference of the two; when the change rate exceeds a threshold value or the communication time sequence is discontinuous, entering voltage limiting constraint control; determining a limiting function according to the change rate and the voltage difference and updating a voltage reference value; adjusting the output voltage according to the updated reference value; and continuously executing voltage reference value updating and output adjustment until the output and the required voltage tend to be consistent, then exiting the voltage limiting constraint, and continuously performing dynamic adjustment according to the required voltage. According to the technical scheme, through dynamic monitoring and voltage difference constraint on the bus and the required voltage, voltage limiting adjustment and reference value smooth updating during sudden change are achieved, the impact current peak value is effectively restrained, and it is ensured that the voltage is stable, the current is limited, and the system operates stably.

The invention discloses a bidirectional direct current circuit breaker which comprises an electronic branch assembly, a voltage limiting branch assembly and an energy consumption branch assembly. The electronic branch assembly is used for transferring current; the voltage limiting branch assembly is electrically connected with the electronic branch assembly in parallel so as to reduce the turn-off overvoltage of the circuit breaker; and the energy consumption branch assembly is electrically connected with the electronic branch assembly in parallel so as to be used for absorbing the energy of the circuit. According to the hybrid DC circuit breaker, the current transfer function of the hybrid DC circuit breaker can be realized through the electronic branch assembly, the voltage limiting branch assembly and the energy consumption branch assembly. Compared with a bidirectional direct-current circuit breaker based on a power electronic device in the related technology, the bidirectional direct-current circuit breaker is compact in structure, low in connection inductance and high in universality, and functional units can be configured. The problems that in the related technology, connection is complex, redesign is needed under different working conditions, and functional units are inconvenient to adjust are solved.

The invention discloses a torque ripple suppression method for a permanent magnet synchronous motor under a limited voltage, and belongs to the technical field of power generation, power transformation or power distribution. The method comprises the following steps: acquiring torque data changing along with a rotor position under different excitation currents, and establishing a torque three-dimensional look-up table model of the torque about a shaft current and the rotor position; respectively establishing optimization targets for a low-rotating-speed working condition and a high-rotating-speed working condition, and establishing a stator current two-dimensional table look-up model under the low-rotating-speed working condition and a stator current three-dimensional table look-up model under the high-rotating-speed working condition in combination with the torque three-dimensional table look-up model; an optimized stator current algorithm model is established according to the stator current look-up table model, the stator current two-dimensional look-up table model or the stator current three-dimensional look-up table model is switched according to the criterion of direct current voltage out-of-limit, and the query value of the optimized stator current is used as a stator current reference value for vector control of the permanent magnet synchronous motor. While low-speed copper loss reduction and high-speed speed regulation range expansion are taken into consideration, overall torque harmonic suppression under a voltage limited working condition is realized.

A power supply control method, power supply, and computer program product are applied to the power supply technology field. The power supply control method includes: obtaining a currently configured target output value and a target limit value; obtaining a currently measured voltage value and a currently measured current value of the circuit; if a source operating mode is satisfied, determining the feedback time relationship between a current loop control module and a voltage loop control module; if the feedback time of the current loop control module is less than the feedback time of the voltage loop control module, controlling the current to reach the current limit value or current output value between the target output value and the target limit value; otherwise, controlling the voltage to reach the voltage limit value or voltage output value between the target output value and the target limit value based on the voltage loop control module. Because the power supply output can be controlled by switching to a control module with a shorter feedback time, voltage and current switching can be performed smoothly, thereby avoiding overshoot and inflection points.

The invention relates to the field of explosion-proof electrical technology, and discloses an intrinsically safe output Ethernet transmission circuit, which comprises an Ethernet physical layer transceiver chip U6, a network transformer U7, an electrostatic protection diode D17, an electrostatic protection diode D18, voltage stabilizing diodes D13-16, capacitors C46-62, resistors R42-45, resistors R59-65, thick film resistors R74-77, fuses F1-4, a safety Y capacitor CY1, an inductor L2, a gas discharge tube TV1, a gas discharge tube TV2 and an RJ45 connector RJ1. The intrinsically safe output Ethernet transmission circuit provided by the invention realizes 3000V voltage isolation, has the characteristics of low cost and easiness in implementation, not only has strong anti-interference and lightning surge protection capabilities and stable transmission performance, but also is easy to calculate and check intrinsically safe parameters through multi-stage isolation and current-limiting and voltage-limiting protection, and has a wide application prospect. And multiple key problems in intrinsic safety Ethernet transmission are effectively solved.

The invention discloses a photovoltaic string medium-voltage convergence system, and belongs to the technical field of photovoltaic power generation, the system realizes voltage level jump through a + / -1500V bipolar symmetric architecture, and a plurality of 1500V photovoltaic strings are configured to have positive electrodes and negative electrodes symmetrically arranged to form a medium-voltage convergence system with the total output voltage of 3000V. And meanwhile, the stability of the system is maintained through the midpoint high-resistance grounding device, and the voltage limitation of a traditional 1500V system is broken through on the premise of not changing the insulation and voltage resistance level (1500V) of the existing equipment. According to the scheme, the direct current side transmission loss and the cable cost are remarkably reduced, the confluence radius is expanded, existing photovoltaic modules, cables and matched equipment are compatible, and an efficient and economical confluence solution is provided for a large photovoltaic power station.

The invention relates to a rotating shaft assembly, a grounding part and electronic equipment, the rotating shaft assembly comprises a rotating shaft and the grounding part, the grounding part is arranged between the rotating shaft and a rotating shaft back cover in the electronic equipment and is electrically connected with the rotating shaft back cover and the rotating shaft to form a grounding circuit, and the grounding part comprises a voltage limiting element. When the voltage in the grounding circuit is greater than or equal to a first threshold value of the voltage limiting element, the voltage limiting element conducts the grounding circuit; when the voltage in the grounding circuit is smaller than the first threshold value of the voltage limiting element, the voltage limiting element disconnects the grounding circuit. The rotating shaft assembly is simple in structure, easy to manufacture and low in cost, the ESD grounding requirement of the rotating shaft back cover and the daily use requirement of a user can be met at the same time, the service life of a metal appearance part outside the electronic equipment is prolonged, and the use safety of the electronic equipment is improved.

The application discloses a voltage-limited overvoltage protection component with a recoverable electromagnetic drive tripping mechanism, which is composed of a voltage-limited overvoltage protector and an electromagnetic drive tripping mechanism. In a normal state, the normally closed contact of the electromagnetic drive tripping mechanism is in a closed state, which does not affect the normal working state of the voltage-limited overvoltage protector and the protection state under a normal intensity overvoltage. When an overvoltage occurs, a pulse current flowing through the voltage-limited pressure-sensitive resistor induces a current in the upper metal disc of the electromagnetic drive tripping mechanism, which is opposite to the direction of the spiral conductor coil of the lower electromagnetic drive disc, so that the upper metal disc of the lower electromagnetic drive mechanism induces an electromagnetic repulsive force with the lower electromagnetic drive disc, thereby causing the normally closed contact of the electromagnetic drive tripping mechanism to break, effectively inhibiting the continuous effect of a subsequent power frequency or direct current arc on the voltage-limited protector, prolonging the service life of the voltage-limited overvoltage protection component, and effectively realizing the safe use coefficient and prolonging the service life of the voltage-limited overvoltage protection component.

The invention relates to an electronic device (100), comprising:-a switching device (102) for switching a main current path (103), the switching device (102) having n semiconductor switching cells (102.1, 102.2,..., 102. N) connected in series, where n is a natural number other than zero,-a voltage limiting device (114) connected in parallel with the switching device (102), the invention relates to a voltage limiting device (100), comprising at least one overvoltage protection means (107) and at least one bidirectional trigger diode (109) connected in series with the at least one overvoltage protection means (107), and n overvoltage arresters (110, 110.1, 110.2,..., 110. N), each of the n overvoltage arresters (110, 110.1, 110.2,..., 110. N) being connected in parallel with each of the n semiconductor switching units (102.1, 102.2,..., 102. N) in a bijection-dependent manner.

To suppress application of an excessive voltage to a specific electrolytic capacitor.SOLUTION: A voltage adjustment device (10a) connected to a series circuit of a plurality of electrolytic capacitors (C[1], C[2]) provided between ground wiring and input voltage wiring includes a high-side terminal and a low-side terminal (TMH, TML) connected to the input voltage wiring and the ground wiring, an intermediate terminal (TMM[1]) connected to a connection node between the plurality of electrolytic capacitors, and voltage limiting circuits (11H-13H, 11L-13L) that limit a voltage between the high-side terminal and the intermediate terminal to a high-side limit voltage or less by controlling a high-side adjustment current (IH) between the terminals in accordance with a voltage therebetween, and limit a voltage between the intermediate terminal and the low-side terminal to a low-side limit voltage or less by controlling a low-side adjustment current (IL) between the terminals in accordance with a voltage therebetween.SELECTED DRAWING: Figure 7

This invention relates to a voltage limiting control method for a series-type offshore wind power DC collector system, comprising: superimposing a low-voltage DC link voltage control loop on the power control loop of the wind turbine generator-side converter, and obtaining a reference value for the d-axis component of the generator-side converter voltage. umsd_ref and q-axis component reference value umsq_ref The control signal for the generator-side converter is generated through sinusoidal pulse width modulation to maintain stable low-voltage DC link voltage while ensuring stable power output. The grid-side converter of the wind turbine adopts voltage / frequency control to obtain the d-axis reference value of the grid-side converter output voltage. uod _ ref and q-axis reference value uoq _ ref The grid-side converter control signal is generated by sinusoidal pulse width modulation. By setting the d-axis setpoint of the grid-side converter output voltage, the AC output voltage of the grid-side converter is limited, thereby controlling the DC output voltage of the wind turbine generator within the limit value.

Electrical protection device, associated electrical installation and control method The present invention relates to an electrical protection device comprising: a mechanical switch; an interruption cell (18) comprising N switching modules (32, 42), N being greater than or equal to 2, each switching module (32, 42) comprising a voltage limiting element (39, 49), each voltage limiting element having a different limiting voltage (Ulim1, Ulim2);a control unit comprising a cell control module (66), configured to control each switching module in the blocked configuration, the limiting voltages, alone and / or summed together, form at least 2N-1 distinct steps, and the cell control module is configured to control in the blocked configuration the switching module(s) whose limiting voltages form a step being the largest step less than or equal to a dielectric withstand of the mechanical switch. Figure for the abbreviation: Figure 2;

According to the present invention, a power conversion unit converts a DC voltage of a DC power supply into an AC voltage and applies the AC voltage to a rotary machine, a current detection unit detects a current supplied from the power conversion unit to the rotary machine, and a power conversion control unit issues a switching command to the power conversion unit, generates a first voltage command to be applied to the rotary machine on the basis of the detected current, calculates, on the basis of a d-axis voltage on a d-axis and a q-axis voltage on a q-axis, which are synchronized with the rotation of the rotary machine, the phase of a second voltage command so as to be equal to the phase of the first voltage command, and determines, as the amplitude of the second voltage command, a voltage limit value corresponding to the DC voltage of the DC power supply.

A voltage protection circuit, comprising a dV / dt triggered turn-on circuit configured to receive an input voltage and to turn on a switch when a change in voltage over time exceeds a predetermined level. A voltage limiting circuit coupled to the dv / dt triggered turn-on circuit and configured to limit a maximum voltage seen by the dV / dt triggered turn-on circuit. A current sharing circuit coupled to the dV / dt triggered turn-on circuit and configured to control a level of current through the dV / dt triggered turn-on circuit. A level shifting circuit coupled to the dV / dt triggered turn-on circuit and configured to shift a DC voltage level of the dV / dt triggered turn-on circuit.

The invention discloses a power output circuit and a power output method.The power output circuit comprises a constant-current module, a constant-voltage module and a master control module.The master control module receives an external input instruction, generates a first control signal and a second control signal according to the external input instruction and outputs the first control signal and the second control signal to the constant-current module; the first control signal is output to the constant-current module, and the second control signal is output to the constant-voltage module, so as to control the constant-current and constant-voltage output of the input power supply. Through the scheme, constant-current and constant-voltage output of the input power supply is realized, 0-40A adjustable current and 1.25-6.25 V adjustable voltage can be provided on the premise that a 5V safety voltage threshold is not exceeded, and the technical effects of large-current output and wide-range voltage adjustability under strict voltage limitation are realized.

A method for operating an electrochemical stack (10) comprising a plurality of electrochemical cells (1), each cell having an anode compartment (2) with an anode electrode (6) and a cathode compartment (3) with a cathode electrode (7), wherein the anode compartment (2) and the cathode compartment (3) are separated from each other by a semipermeable membrane (8). An electrical voltage is present between the anode electrode (6) and the cathode electrode (7) during operation, with the electrochemical cells (1) being connected in series. A cell voltage monitoring unit (17) is connected to the electrochemical cells (1). The method is characterized by - Measuring electrical voltages U i using the cell voltage monitoring system (17) of n electrochemical cells connected in series, where n is greater than or equal to 2, - Comparing the measured voltages U i with a maximum voltage U exp,nand a minimum voltage U min,n , where the maximum voltage U exp,n n times the maximum possible cell voltage of a single electrochemical cell U exp is and U min,n the (n-1) times the maximum possible cell voltage of a single cell (1) plus a lower voltage limit U Limit , where U Limit the smallest cell voltage down to which operation of a single electrochemical cell (1) is to be carried out, - Output an error message if at least one of the measured voltages U i smaller than U min,n or larger than U exp,n is.

The invention discloses a field weakening trajectory tracking control method for permanent magnet synchronous motors based on enhanced model predictive current control, comprising: S1, establishing a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system and determining the optimal operating trajectory in the field weakening region; S2, constructing an extended virtual voltage vector set synthesized from the basic voltage vector, and constructing a virtual voltage vector containing continuous components, excess components, and disturbance components as feedback quantities, which are adjusted by the field weakening current controller. d The shaft reference current limits the virtual voltage amplitude within the inverter output voltage limit; S3, a nonlinear extended state observer based on a nonlinear function is designed to estimate the current state and total disturbance in real time, and correct the current prediction model. The optimal voltage vector is selected through a cost function, and a switching pulse sequence is generated to drive the inverter. This invention can effectively reduce current ripple when motor parameters are mismatched and overcome the deviation of the field weakening trajectory when model parameters are mismatched.

System which includes the following: a peak current mode controller for controlling the cycle operation of a power switch in a switching power converter for controlling an output voltage to a nominal value, wherein the peak current mode controller includes a comparator (520) to generate a turn-off command in response to a comparison of a multiplied fault signal with a signal (Isense) representing an input current into an AC / DC power converter; an upper threshold voltage (VOUT-limit) matching circuit (530) configured to increase an upper threshold voltage (VOUT-limit) in response to an increase in a voltage ripple between the output voltage and the nominal value, wherein the upper threshold voltage (VOUT-limit) matching circuit (530) is further configured to decrease the upper threshold voltage in response to a decrease in the voltage ripple; a lower threshold voltage (VOUT lower limit) matching circuit (535) configured to decrease a lower threshold voltage (VOUT lower limit) in response to an increase in voltage ripple, wherein the lower threshold voltage (VOUT lower limit) matching circuit (535) is further configured to increase the lower threshold voltage in response to a decrease in voltage ripple; and a mode control circuit (525) configured to allow the comparator (520) to control the cycling of a power switch when an output voltage for the switching power converter is both lower than the upper threshold voltage (VOUT upper limit) and higher than the lower threshold voltage (VOUT lower limit), and to prevent the comparator (520) from controlling the cycling of the power switch when the output voltage is higher than the upper threshold voltage (VOUT upper limit) or lower than the lower threshold voltage (VOUT lower limit).

The invention belongs to the field of vehicle-mounted electronic product power supply, and particularly discloses a stabilized power supply output system and an output method thereof.The system comprises a voltage reference chip, a first triode, a second triode, a power MOS tube, a first resistor, a second resistor, a third resistor and a fourth resistor; the third resistor and the fourth resistor are connected in series between the power output end and the ground, the voltage dividing point is connected with the base electrode of the second triode, the emitter electrode is grounded through the first resistor, and the collector electrode is connected with the source electrode of the power MOS tube through the fifth resistor and used for adjusting the voltage stabilizing output voltage limit value according to the normal working voltage limit value of a back-stage load. When the voltage of the input end is smaller than the set voltage-stabilizing output voltage limit value, the output voltage is kept consistent with the input voltage, and when the voltage of the input end is larger than the set voltage-stabilizing output voltage limit value, the output voltage is kept at the set voltage-stabilizing output voltage limit value. The circuit can meet the requirement of a large-power load, and can still work normally when the power supply voltage changes.

The application discloses a short-circuit recovery voltage limiting method for a three-stage direct-current generator, which detects output voltage U0 of the three-stage direct-current generator and load current i L to determine the state of the load, adjusts the output state of the three-stage direct-current generator according to the state of the load by using an asymmetric half-bridge excitation topology, detects the generation output voltage and the load current to determine characteristic states such as a short-circuit state, a short-circuit recovery state and a first voltage peak falling edge after short-circuit recovery, and closes upper and lower excitation power tubes in combination with the asymmetric half-bridge during short-circuit recovery, so that the two power tubes are opened only when the first voltage peak falls to a voltage undervoltage value after short-circuit recovery, and voltage overshoot during short-circuit recovery of the three-stage direct-current generator is limited to the maximum extent, and the safety of a power supply system is ensured.