1367 results about "Over current protection" patented technology

The invention is suitable for the technical field of LED backlight driving, and provides a starting control circuit for LED backlight driving, a chip and a display device. The starting control circuit of the LED backlight drive comprises a detection selection module, an error amplification module, a first change-over switch module, a control module, a second change-over switch module, a logic drive module, a feedback module and a first switch module. When each first voltage is in a preset range, the first change-over switch module is used for conducting the first input end of the error amplification module and the output end of the error amplification module. And the second change-over switch module is used for transmitting the overcurrent protection signal to the logic driving module. When the detection voltage is larger than the first reference voltage, the first change-over switch module is used for conducting the first input end of the error amplifier and the detection selection module. And the second change-over switch module is used for conducting the control module and the logic driving module. Therefore, the Boost has more response time to respond to the rapid change of the LED.

The invention discloses a power supply circuit, a power supply method, a server, a product and a medium, and relates to the technical field of server power supply, the total power demand of the server is dispersed through the parallel design of multiple power panels, the bus current of a single board connected to a first voltage is reduced to the safe bearing range of an MOS tube, the impact risk is reduced, and the service life of the server is prolonged. The electronic fuse is matched with the single-board power to set an overcurrent protection threshold value, and the short-circuit protection response time is shortened; each board is independently provided with a power supply brick to realize second voltage localization conversion and single board output current reduction, a multi-board output end combined power supply design is combined, a heat source is dispersed to eliminate heat accumulation, the through-current capability is multiplied through a parallel path, and the heat dissipation and electrical design feasibility of the circuit board is improved. The technical problems of MOS tube over-limit, overcurrent protection delay, circuit board heat accumulation and difficult through-flow caused by large current brought by a power supply in a high-power server are solved, and the technical effects of enhancing power supply reliability and optimizing energy efficiency are achieved.

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 high-voltage power amplifier with an over-temperature and over-current protection circuit, and relates to the technical field of integrated circuits. The high-voltage operational amplifier comprises a high-voltage operational amplifier core unit and a self-adaptive protection circuit unit, the high-voltage operational amplifier core unit comprises a rail-to-rail input stage, a gain amplification stage and an AB type push-pull output stage which are sequentially cascaded, and the AB type push-pull output stage comprises a PMOS upper power tube and an NMOS lower power tube; the self-adaptive protection circuit unit comprises a PMOS (P-channel Metal Oxide Semiconductor) current-limiting protection circuit, an NMOS (N-channel Metal Oxide Semiconductor) current-limiting protection circuit and an over-temperature protection circuit; the PMOS current-limiting protection circuit is used for generating a high-voltage domain over-current control signal when the power tube on the PMOS is over-current; the NMOS current-limiting protection circuit is used for generating a low-voltage domain overcurrent control signal when the NMOS lower power tube is in overcurrent; the over-temperature protection circuit is used for generating high-voltage domain over-temperature turn-off signals and low-voltage domain over-temperature turn-off signals when the amplifier is over-temperature; and finally, carrying out logic synthesis on the corresponding over-current control signal and the over-temperature turn-off signal to generate a gate clamping signal.

The invention discloses an overcurrent protection control circuit of a low-dropout linear regulator and the low-dropout linear regulator, and relates to the field of voltage regulators. A first sampling module is connected with a drain electrode, a grid electrode and a source electrode of a power control tube in the low-dropout linear regulator and a first current comparator; the first current comparator is further connected with the grid electrode of the first protection switch and the input voltage end of the low dropout linear regulator, the source electrode of the first protection switch is connected with the grid electrode of the power control tube, the drain electrode of the first protection switch is grounded, and the source electrode of the power control tube is connected with the voltage output end of the low dropout linear regulator; the second sampling module is respectively connected with the drain electrode of the power control tube, the grid electrode of the power control tube and the clamping module, the clamping module is connected with the grid electrode of the second protection switch through the second current comparator and is also connected with the source electrode of the power control tube, the drain electrode of the second protection switch is grounded, and the source electrode of the second protection switch is connected with the grid electrode of the power control tube. The reliability of current limiting can be improved.

The invention discloses an overcurrent protection circuit and a BUCK type DC-DC converter, and relates to the technical field of integrated circuits. The over-current protection circuit can be applied to a BUCK type DC-DC converter, and comprises an over-current judgment circuit which is connected with the output end of the converter and is used for sampling a current signal output by the converter according to a preset proportion and converting the sampled current signal into an over-current detection signal; the digital logic module is connected with the output end of the overcurrent judgment circuit and the control end of the converter, and is used for sampling the overcurrent detection signal, counting overturning signals of the overcurrent detection signal in each switching period of the converter, judging whether the converter is in an overcurrent state or not on the basis of a count value, and if the converter is in the overcurrent state, outputting the overcurrent detection signal; and if so, outputting a turn-off signal to the converter to turn off the converter. The over-current protection circuit is simple in control logic and low in power consumption, and can prevent the occurrence of false touch in over-current detection.

The invention discloses a frequency converter multi-stage cooperative rapid overcurrent protection circuit, and the overcurrent protection circuit cooperates with an IGBT inverter circuit, an IGBT drive circuit, a current sampling circuit and a master control MCU of a frequency converter to construct a three-stage cooperative protection system composed of hardware-stage extreme rapid protection, hardware-stage rapid protection and software-stage intelligent protection. And independent action and information interaction between the stages can be realized through circuit design. Compared with the prior art, protection blind areas are eliminated, nanosecond-microsecond level extreme protection is achieved, a multiple and high-reliability redundancy protection system is constructed, intelligent grading processing of faults is achieved, and the diagnosability of the system is enhanced.

The invention provides a turn-back overcurrent protection circuit and a linear voltage regulator, and the turn-back overcurrent protection circuit comprises a turn-back switch module which compares an output voltage with a preset voltage, and outputs a turn-back current when the output voltage is smaller than or equal to the preset voltage; and the overcurrent protection module is connected with the turn-back switch module, performs overcurrent protection on the linear voltage regulator based on the first current limiting point when the turn-back switch module does not output the turn-back current, and reduces the current limiting point from the first current limiting point to a second current limiting point based on the turn-back current when the turn-back switch module outputs the turn-back current, and over-current protection is carried out on the linear voltage regulator based on the second current limiting point. According to the invention, the problem of circuit damage caused by overlarge output current due to short circuit or overload in the prior art is solved.

The invention provides a silicon carbide MOS drive control chip overcurrent protection method and device, and the method comprises the steps: setting a forward sampling channel and a reverse sampling channel at a source sampling resistor, setting different sampling time windows for different sampling channels, carrying out the peak shifting setting of the time windows of the double sampling channels, and carrying out the peak shifting setting of the time windows of the double sampling channels, thereby achieving the overcurrent protection of a silicon carbide MOS drive control chip. The time period with the strongest common-mode interference can be avoided; meanwhile, the switching speed of the silicon carbide MOS device is mapped into a theoretical common-mode interference waveform, and the waveform and a bidirectional sampling signal are synthesized, so that a common-mode interference component in the sampling signal can be accurately separated, and the synthesized current signal is more accurate; on the basis, current signals are compensated by combining on-resistance change caused by junction temperature change, and overcurrent protection is carried out by adopting a graded protection strategy. According to the method, the influence of common-mode interference on current sampling is effectively overcome through peak shifting design on sampling channel time and common-mode interference separation based on switching speed.

A level conversion assembly (50), an overcurrent protection method and a display device, the level conversion assembly (50) comprising a level conversion module (51), the level conversion module (51) comprising a control unit (511), a current detection unit (512), a level conversion unit (513) and an overcurrent protection unit (514). When a control unit (511) is at a first falling edge of a digital clock signal (CPV), a first analog clock signal corresponding to the first falling edge in a plurality of analog clock signals (CLK1-CLK8) is determined based on the corresponding relation of the current display mode, and a current detection unit (512) is controlled to detect the current of the first analog clock signal. Since the moment of the falling edge of the digital clock signal (CPV) is located in the last row of the high level period or the low level period in the corresponding analog clock signal, the current detection unit (512) can send an overcurrent signal to the overcurrent protection unit (514) when the current of the first analog clock signal is not located in the current threshold range. The effect of improving the accuracy of over-current phenomenon detection is achieved.

The invention discloses an overcurrent protection method. The method comprises the following steps: acquiring overcurrent protection influence factors, wherein the overcurrent protection influence factors comprise temperature drift and voltage fluctuation; dynamic compensation is carried out on the basic overcurrent threshold value according to the overcurrent protection influence factors, and an overcurrent protection threshold value is obtained; the basic overcurrent threshold value is determined based on a wire harness impedance model; and under the condition that the real-time current value is greater than the overcurrent protection threshold value, triggering an overcurrent protection action so as to realize overcurrent protection of the protected object. Through dynamic compensation of the basic overcurrent threshold and integration of multi-dimensional influence factors such as temperature drift and voltage fluctuation, threshold deviation caused by the temperature drift and the voltage fluctuation is effectively eliminated, false triggering or protection failure is avoided, and the method has the advantages of improving overcurrent protection precision and system stability.

A DC electronic load circuit relates to the technical field of electronic load control. The utility model provides a direct current electronic load circuit which integrates a dissipation MOS tube array, an analog PID loop, a digital integrated control module, a bus electrical parameter sampling and processing module and a WiFi communication module, and realizes a plurality of working modes such as constant current, constant voltage, constant resistance and constant power by accurately controlling the conduction degree of the MOS tube array. The system has the advantages of real-time monitoring, remote control, overvoltage and overcurrent protection, low power consumption design and the like, and an electronic load solution which is high in precision, high in stability and flexible to operate is provided, so that diversified test requirements are met, and the power supply test efficiency and safety are improved.

The utility model relates to the technical field of batteries, and discloses a top cover assembly and a battery. The top cover assembly comprises a cover group assembly and a top cover assembly, the cover group assembly comprises a cover plate and a pole, the cover plate is connected with the opening of the shell, a first through hole is formed in the cover plate, one end of the pole is positioned on the inner side of the cover plate and is electrically connected with the tab of the battery cell, and the other end of the pole extends out of the outer side of the cover plate from the first through hole; the top cover assembly comprises a first connecting piece, a PTC and a top cover body which are sequentially connected in the direction away from the shell, and the first connecting piece is located above the cover plate and electrically connected with the pole. By adopting the arrangement mode, the top cover assembly can be connected with the opening of the shell by adopting a full-sealing structure, so that the battery has good sealing performance; by integrating the PTC, the over-current protection function in the assembling process of the top cover assembly can be achieved, and therefore the safety and reliability of the assembling process of the top cover assembly are guaranteed.

The invention discloses a converter valve multistage thyristor level closed-loop test device which comprises a CPU control module, a photoelectric conversion module, an analog quantity acquisition module, a switching value module, an output control unit, an impedance test unit, an overvoltage and overcurrent protection module, a safety protection module, a man-machine interaction unit module and a power supply module. The CPU control module is respectively connected with the photoelectric conversion module, the analog quantity acquisition module, the switching value module, the output control unit, the impedance test unit, the overvoltage and overcurrent protection module, the safety protection module and the man-machine interaction unit module; the power supply module is connected with the CPU control module, the safety protection module, the photoelectric conversion module, the analog quantity acquisition module, the overvoltage and overcurrent protection module, the switching value module, the output control unit, the impedance test unit and the man-machine interaction unit module. According to the invention, the automation degree and the field adaptability of the test are improved, and the field maintenance efficiency and the visual analysis capability of the operation state of the thyristor are improved.

The embodiment of the invention provides a gallium nitride totem-pole circuit and a control evaluation system of the gallium nitride totem-pole circuit, and the circuit comprises a gallium nitride power device which comprises an integrated semiconductor tube and an integrated drive circuit; the isolation chip is connected between the control module and an integrated driving circuit of the gallium nitride power device and is used for sending the pulse width modulation signal sent by the control module to the integrated driving circuit, and the isolation chip can ensure the electrical safety of weak current and strong current; the gallium nitride power device is used for controlling the on-off state of the integrated semiconductor tube through the integrated driving circuit according to the pulse width modulation signal sent by the isolation chip; under the condition that the integrated semiconductor tube is conducted, the voltage is output to the control module based on the bus voltage through the integrated semiconductor tube, and the driving circuit is integrated on the gallium nitride power device, so that the circuit design can be simplified, overcurrent protection and undervoltage protection are simultaneously carried out, and the safety of the gallium nitride totem pole circuit is improved.

A mainboard protection system and method are provided. A precision resistor is arranged between an overcurrent protection component and a voltage regulator, and the precision resistor is connected to a current monitoring circuit. The current monitoring circuit is connected to a complex programmable logic device, and transmits, w detecting that a voltage difference of the precision resistor is greater than a set threshold, an early-warning signal to the complex programmable logic device. The complex programmable logic device is connected to a processor and sends, when receiving the early-warning signal, an interrupt signal to the processor. in response to receiving the interrupt signal, the processor cuts off outputting of the overcurrent protection component.

The utility model discloses a current metering circuit for a protection board, which comprises a charging and discharging protection circuit, a current acquisition circuit and a controller circuit, and is characterized in that the charging and discharging protection circuit is used for carrying out charging and discharging protection control on a battery; the current acquisition circuit comprises a current sampling resistor R39 and a current signal processing circuit, the current sampling resistor R39 is used for sampling current, and a signal input end of the current signal processing circuit is connected with the current sampling resistor R39 so as to output the sampled current after processing the sampled current; and the controller circuit carries out overcurrent protection control and / or carries out flow statistics output on the current through the charging and discharging protection circuit according to the sampling current. Therefore, a special metering chip is replaced by the independent current signal processing circuit and the controller circuit, so that the implementation of the whole metering function is cheaper, the controller circuit can transmit current metering signals to the outside in a wired or wireless mode, and the application is more flexible.

The invention relates to the field of ceramic materials, provides a high-voltage-resistant PTC (Positive Temperature Coefficient) thermal sensitive ceramic material as well as a preparation method and application thereof, and aims to improve the voltage resistance and PTC effect stability of thermal sensitive ceramic. The material is composed of aluminum oxide-coated manganese-doped barium titanate nanorods, hollow-core silicon dioxide microspheres and a glass phase sintering aid, and the electric heating performance and the microstructure stability are optimized by constructing a core-shell structure and a three-dimensional composite system. A hydrothermal method and a sol-gel method are adopted to precisely control a raw material structure, and alcohol dispersion, tape casting and weak oxidizing atmosphere sintering are combined, so that the compactness and consistency of the ceramic are ensured. The material is suitable for high-voltage temperature control elements and over-current protection devices, and is widely applied to the fields of new energy automobile battery pack over-temperature protection, high-voltage power equipment current limiting elements, industrial automatic temperature control switches and the like.

The invention relates to power semiconductor device on-line monitoring and power electronic system control, in particular to a SiC MOSFET conduction current extraction circuit and method, high-frequency oscillation interference is effectively suppressed through a second-order passive RC filter circuit, a measurement error less than or equal to 1.5% is realized within a current range of 50A-300A in combination with an accurate mathematical model established by a depth symbol optimization algorithm, and the measurement accuracy is improved. The requirement of the intelligent gate driver on high-precision current feedback is met, and the measurement precision is remarkably improved; the pulse width direct analysis technology is adopted, a traditional active integrator and a digital decoding link are omitted, the system response delay is smaller than or equal to 500 ns, microsecond-level over-current protection can be supported, the response speed and the real-time performance are optimized, and the system safety in a high-frequency application scene is remarkably improved.

The invention relates to the technical field of charging control, and provides an intelligent control method and system for a high-power charging module, and the method comprises the steps: obtaining a charging state sequence of the charging module, carrying out the feature extraction and mode recognition processing of the charging state sequence, and obtaining a charging safety control parameter; performing hierarchical calculation on the charging safety control parameters to obtain a dynamic safety level, generating an overcharge protection signal and an overcurrent protection signal by using the dynamic safety level, and performing data mapping calculation on the overcharge protection signal and the overcurrent protection signal to obtain a real-time protection strategy; and generating a charging module control instruction according to the real-time protection strategy, and controlling the charging process of the charging module based on the charging module control instruction. Through hierarchical calculation of charging safety control parameters, a charging module control instruction is generated to control a charging process, and the problems of low charging efficiency and poor safety in a scene with a complex charging environment and dynamic demand change are solved.

The invention discloses an energy storage converter and an overcurrent protection circuit and an overcurrent protection method thereof. The overcurrent protection method comprises the following steps: acquiring the equipment temperature and the output current and voltage of the energy storage converter; calculating a current change rate based on the acquired output current; the current real-time temperature is adjusted on the basis of the reference over-current protection threshold value, the voltage collected in real time is applied to the adjusted over-current protection threshold value according to the set proportion, and meanwhile, the current change rate obtained through real-time calculation is applied to the adjusted over-current protection threshold value according to the set proportion. Obtaining a result of a dynamic overcurrent protection threshold value; comparing the dynamic over-current protection threshold value with the output current of the energy storage converter, if the dynamic over-current protection threshold value is exceeded, triggering to execute a protection action, generating a control instruction, and tripping off a switch device for controlling the operation of the energy storage converter; and if not, continuously monitoring and comparing the output current with the dynamic overcurrent protection threshold.

The present application discloses an intelligent power protection control method, device, and intelligent power supply. The method includes: performing curve fitting on i historical voltages to obtain a historical voltage curve; performing curve fitting on j historical currents to obtain a historical current curve; determining a first voltage curve of the intelligent power supply in a future time period according to the historical voltage curve; determining a first current curve of the future time period according to the historical current curve; determining an overvoltage protection threshold curve and an undervoltage protection threshold curve according to the load power curve of the future time period; determining an overcurrent protection threshold curve according to the load power curve; determining a target critical point according to the first voltage curve, the first current curve, the overvoltage protection threshold curve, the undervoltage protection threshold curve, and the overcurrent protection threshold curve; and controlling a protection device to perform a power protection operation corresponding to the target critical point. The present application is beneficial to improving the safety of the intelligent power supply.

The invention discloses a PFC (Power Factor Correction) circuit suitable for electrode high-voltage discharge. The PFC circuit comprises an EMI (Electro-Magnetic Interference) filtering module, a starting protection module, a PFC power conversion module and a PWM (Pulse-Width Modulation) switch type auxiliary power supply module which are connected in sequence. The EMI filtering module realizes bidirectional suppression of interference, and when the circuit is powered off, the bleeder resistor enables the common mode inductor and the differential mode capacitor to rapidly discharge, so that secondary interference is prevented; according to the PWM switch type auxiliary power supply module, a high-voltage area and a low-voltage area are isolated, and it is guaranteed that the power supply input pin of the control chip U2 / U3 can be within the normal working voltage; according to the invention, the control chip U2 limits the PWM duty ratio of the control chip U3 through the control logic, so that overcurrent protection is realized; when the MOS tube Q1 / Q2 is conducted, the resistor R22 consumes energy generated by discharging of the capacitor C21, meanwhile, resonance between the capacitor C21 and the energy storage inductor L2 is restrained, high-frequency electromagnetic interference is prevented, and electromagnetic compatibility of the whole system is achieved.

The invention provides a probe power supply over-current protection circuit and an over-current protection method thereof, relates to the technical field of power electronics, and solves the problems that periodic instantaneous over-current and continuous fault over-current are difficult to accurately distinguish and a control signal and a protection system lack a linkage mechanism in the prior art. In the circuit, a current detection unit generates a single over-current trigger signal when detecting a single over-current event; the central control unit sends a blocking signal after receiving the single overcurrent trigger signal, and sends a reset signal after preset time delay; meanwhile, cumulative counting is carried out on single overcurrent trigger signals, and whether an overcurrent fault occurs or not is judged according to a preset threshold number of times; the output control unit is used for controlling the closing and resetting of a probe power supply under the action of different signals; and the state feedback unit feeds back state information to the main control system when an overcurrent fault occurs. According to the invention, accurate response to the ELM overcurrent of the Tokamak device and reliable blocking of persistent faults are realized.

The invention discloses an efficient synchronous rectification BUCK circuit based on a silicon carbide MOSFET, and the circuit comprises a digital controller, the output end of the digital controller is sequentially connected with a silicon carbide MOSFET driving unit and a DC / DC conversion unit, and the DC / DC conversion unit is connected with an output Vout. The input end of the digital controller is connected with the temperature sensor, the frequency adjusting unit and the self-adaptive dead time adjusting unit. The output Vout is further connected with the digital controller through the SW zero-crossing comparison unit, the overcurrent protection unit and the feedback and compensation network unit. A silicon carbide MOSFET is used as a switching device, the dead time is dynamically adjusted in combination with a frequency-temperature two-parameter mapping algorithm, lossless current detection and overcurrent protection are realized by using a device on-resistor Rds (on), and zero-current turn-off control is realized based on SW node voltage real-time monitoring.

The invention discloses a safety test method and device for a charging pile and electronic equipment. The method comprises the steps that a charging pile of a new energy automobile is tested through a preset unit and a simulation unit, first data, second data and third data are obtained, the preset unit at least comprises a resistor, a capacitor and an inductor, and the simulation unit is used for simulating different operation states of a power grid; the first data is used for representing an island protection test result of the charging pile, the second data is used for representing an overvoltage protection test result of the charging pile, and the third data is used for representing an overcurrent protection test result of the charging pile; and determining a safety test result of the charging pile according to the first data, the second data and the third data. The technical problem that in the prior art, the safety of the operation process of the charging pile connected to the power grid is low is solved.

The utility model discloses a mining intrinsic safety type DC-DC conversion device comprising a hardware circuit which comprises a single-end flyback switching power supply module, a voltage stabilization module, an overvoltage protection module and an overcurrent protection module. The single-end flyback switching power supply module comprises a PWM control module and a voltage transformation module. The overvoltage protection module comprises a first-stage protection circuit, a second-stage protection circuit and a third-stage protection circuit; the overcurrent protection module comprises a first-stage protection unit and a second-stage protection unit, the first-stage protection unit comprises a current sampling protection circuit, the second-stage protection unit comprises a gold resistor, and the gold resistor is externally connected with the output end of the hardware circuit. According to the mining intrinsic safety type DC-DC conversion device, the overvoltage protection module and the overcurrent protection module are arranged, so that the voltage and current protection requirements of the mining intrinsic safety type DC-DC conversion device are met.

The invention discloses a torque motor driving control circuit. The circuit comprises an auxiliary power supply module, an ACM32 control system, a DRV8301 drive circuit, a three-phase inverter circuit, a current detection circuit, a three-phase overcurrent protection circuit, a bus voltage detection circuit and a magnetic encoder circuit. Wherein the auxiliary power supply module realizes redundant power supply through an AMS1117 linear voltage regulator or a DRV8301 built-in BUCK circuit; the DRV8301 driving chip integrates the functions of MOS tube driving, BUCK power supply and current amplification, and the circuit structure is simplified; the three-phase overcurrent protection circuit realizes rapid hardware protection based on an LMV331 comparator; the magnetic encoder adopts an MT6826 chip to replace a traditional photoelectric encoder, multi-mode output and SPI configuration are supported, and the detection precision and the integration degree are improved. According to the invention, the response speed and control precision of the system are optimized through modular design, and the stability and reliability are enhanced.

The invention relates to an over-current protection circuit of a synchronous step-down DC-DC converter, and the over-current protection circuit is characterized in that one end of the over-current protection circuit is connected with one end of a power conversion circuit, the other end of the over-current protection circuit is connected with a power supply, and the other end of the power conversion circuit is connected with the power supply; and the overcurrent protection circuit is used for controlling the power tube to be closed when overcurrent occurs in the power tube in the power conversion circuit, and controlling the power tube to be opened after a preset duration. The overcurrent protection circuit can solve the overcurrent problem of the power conversion circuit.

The invention discloses a vehicle-mounted charging and discharging system and method based on a V2G technology, and relates to the technical field of electric vehicle charging and discharging. The system comprises a power grid interaction module used for performing power grid connection confirmation, overcurrent protection, leakage protection and grid-connected synchronous detection; the man-machine interaction module is used for displaying a charging and discharging setting interface and battery state information and supporting remote operation of a user; the communication module is used for realizing information interaction with an external power grid dispatching center and a cloud management platform; the vehicle-mounted charging and discharging module is used for adjusting charging and discharging voltage and current of a vehicle power battery; the battery management module is used for collecting state parameters of a vehicle power battery and controlling and protecting the charging and discharging process. The control center module is used for monitoring battery parameters, receiving a user instruction and an external power grid dispatching signal, predicting the power of a vehicle power battery and generating a charging and discharging plan. The method can improve the flexibility and economy of the electric vehicle participating in the power grid interaction, guarantees the safety of the battery, and prolongs the service life of the battery.