973 results about "Over current protection" patented technology

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 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 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.

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 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 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 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.

The invention is suitable for the technical field of LED backlight driving, and provides a starting time sequence control circuit and a control chip. The starting time sequence control circuit comprises a switching module, a comparison module, a threshold adjusting module and a switch module, the comparison module is electrically connected with the switching module, the threshold adjusting module and the switch module, the switching module is electrically connected with the detection selection module and the error amplification module, and the comparison module is electrically connected with the feedback module. The threshold adjusting module is electrically connected with the logic driving module, and the switch module is electrically connected with the logic driving module and the control module. According to the starting time sequence control circuit provided by the embodiment of the invention, the error amplification module is configured as the unity gain buffer in the starting stage, and the error amplification module and the control module are connected to the closed loop when the output voltage is close to the target value; and the over-current protection threshold value is gradually increased through the threshold value adjusting module so as to relax the staged cooperative control logic of the current limitation, so that the stable rise of the output voltage is realized.

The invention discloses an intelligent opening and closing method and system for a reclosing circuit breaker based on an electromagnet, and relates to the field of intelligent control, and the method comprises the steps: monitoring a line current in real time, comparing the line current with a preset threshold value, and carrying out the opening after the overcurrent abnormality is detected. Entering a first time delay stage after opening, comprehensively evaluating the states of the circuit breaker and the circuit, and constructing a dynamic weight index system to calculate an evaluation score; if the score exceeds a threshold value, closing is carried out after time delay is finished, otherwise, an alarm is triggered. And entering a second delay stage after switching on, continuously monitoring the electric parameters and establishing an anomaly judgment mechanism, forming a closed-loop protection process of monitoring, switching off, evaluating, switching on and re-monitoring, and realizing intelligent linkage of overcurrent protection and state self-adaption. The method has the advantages that through real-time line electric parameter monitoring, multi-dimensional state evaluation and an intelligent decision-making mechanism, precise opening and closing of the circuit breaker are achieved, the power supply reliability is improved, the power failure time is shortened, and the misoperation risk is reduced.

Systems and methods for implementing over current protection for wireless power devices is described. The method can include receiving alternating current (AC) power from a wireless power transmitter. Rectifying the AC power into a rectified voltage. Generating an output voltage using the rectified voltage. Determining whether an output current of the output voltage can be within a range of current values. In response to output current being within the range of current values, regulating the rectified voltage to a level that minimizes a difference between the rectified voltage and the output voltage. In response to output current being outside of the range of current values, determining whether output current can be greater than or less than an upper bound of the range of current values. In response to the output current being greater than the upper bound of range of current values, shutting down the wireless power transfer system.

The invention relates to a switch module control circuit and an energy storage power supply. The switch module control circuit comprises a power supply circuit, a locking module, a detection module and a driving module. The power supply circuit is arranged between a power supply end and a load end, and a switch module and an overcurrent protection element are arranged on the power supply circuit; the overcurrent protection element is used for being disconnected when the current output by the power supply circuit is larger than a preset current threshold value. The locking module is used for outputting a locking signal when the driving signal of the switch module is a high level, and the high level is a corresponding signal for driving the switch module to be conducted; the detection module is used for bypassing the locking signal when the power supply circuit is switched on; and the driving module is used for controlling the switch module to be switched off when the locking signal is received, and controlling the switch module to be switched on based on the driving signal when the locking signal is not received. By adopting the switch module control circuit, the reliability of the switch module on the power supply circuit of the energy storage power supply can be improved.

The invention relates to the technical field of circuit breakers, and provides a self-adaptive overcurrent protection method and system for an explosion-proof circuit breaker. The method comprises the following steps: determining electrical equipment connected with an explosion-proof circuit breaker bus; carrying out load type judgment, analyzing current waveform dynamic characteristics according to the type, and constructing an overcurrent threshold mapping decision relation; collecting current environment data, analyzing the influence of the current environment data on the current bearing capacity, and generating a current bearing capacity decline index; and optimizing an over-current threshold mapping decision relation in real time according to the index, and performing over-current monitoring and protection action triggering on the bus according to the optimized mapping decision relation. The technical problems that the overcurrent setting value of a traditional explosion-proof circuit breaker is fixed, and different load working conditions and environment derating cannot be considered at the same time, so that the protection accuracy and adaptability are insufficient are solved, the overcurrent threshold value is adaptively set in real time according to the load pulse characteristic and the environment current bearing capacity, and the protection accuracy and adaptability are improved. And the over-current protection accuracy and adaptability of the explosion-proof circuit breaker are improved.

A short-circuit protection circuit of a half-bridge driving chip relates to the field of short-circuit protection and integrated circuit design, and comprises a pre-driving module for generating a high-side signal and a low-side signal; the half-bridge module is driven, a high-side MOS receives a high-side signal, and a low-side MOS receives a low-side signal; the gate source hardware clamping module is used for carrying out voltage clamping on the high-side MOS when over-current of the over-ground short circuit of the high-side MOS is detected; the phase voltage short-circuit protection module is used for controlling the overcurrent time when the high-side MOS short circuit is over-current, and sending a fault signal to the logic module when detecting that the high / low-side MOS short circuit is over-current; the bus over-current protection module is used for sending a fault signal to the logic module when bus over-current is detected; and the logic module judges whether the short-circuit protection circuit enters a protection state according to the fault signal. According to the invention, the response speed and the protection mechanism are intelligently switched in real time in different overcurrent fault scenes through the three-stage protection circuit, and the circuit has the characteristics of high sensitivity, fast response speed and strong anti-interference capability.

A meter collar adapter including a housing, a plurality of contacts to electrically connect the meter collar adapter to a meter socket and to a utility meter, a load management device within the housing to manage electrical load to an interface circuit with external, co-located electric equipment, and an overcurrent protection device electrically connected in series with an interface circuit. The load management device includes the interface circuit to electrically connect to either the line side or load side of an electrical service via the utility meter an external, co-located electric equipment. An interface contact to electrically connect the co-located electric equipment to the interface circuit, an adjustable electrical switch electrically configured to control electric load, and an energy management unit to control, monitor, and / or report a position of the adjustable electrical switch to manage the electrical loads.

The present disclosure relates to a power supply circuit and a vehicle. The power supply circuit comprises: a detection module and a switch control module, wherein the switch control module comprises a first switch unit and a second switch unit; the detection module is used for detecting an access voltage of the power supply circuit; the detection module generates a first level signal on the basis that the access voltage is greater than a threshold voltage of the detection module, and outputs the first level signal to the switch control module; the detection module generates a second level signal on the basis that the access voltage is less than the threshold voltage of the detection module, and outputs the second level signal to the switch control module; the second switch unit is switched to an off state after receiving the first level signal, and controls the first switch unit to turn off; and the second switch unit is switched to an on state after receiving the second level signal, and controls the first switch unit to turn on. The protection circuit provided in the present disclosure adds an automatic overcurrent protection function, has a lower cost, and has a stable main power supply always-on capability.

The invention discloses a distribution line protection method, device and equipment with an excitation inrush current identification function, and a storage medium. The method comprises the following steps: collecting a current signal and a voltage signal of a distribution line in real time; the current signal is used for harmonic component extraction, and the voltage signal is used for constructing an auxiliary criterion variable; the position state of the circuit breaker is monitored in real time, the current closing / tripping state of the circuit breaker is judged to trigger a closing event, and an inrush current recognition mode is started; and on the basis of the inrush current identification mode, the excitation inrush current condition is judged in combination with a multi-feature criterion, and the distribution line is protected. On the basis of existing over-current protection function configuration, secondary harmonic content judgment logic is added, based on the characteristics that the secondary harmonic content of magnetizing inrush current is high, bus voltage is normal and waveform is asymmetric, line misoperation caused by the magnetizing inrush current is prevented through the secondary harmonic content, meanwhile, a voltage criterion is added to avoid faults and inrush current, and therefore the over-current protection function is achieved. While the overcurrent protection action is ensured to quickly cut off the fault, the protection misoperation caused by inrush current during switching on can be prevented.

The invention relates to a driving circuit and a driving method of a display panel and the display panel, the driving circuit comprises a time schedule controller, a memory and a level translator, the time schedule controller is provided with a first communication port, a second communication port and a third communication port, the second communication port is connected with the memory, the third communication port is connected with the level translator, and the level translator is connected with the memory. Wherein the time schedule controller is used for acquiring a refresh rate adjustment instruction, acquiring an overcurrent protection parameter corresponding to the refresh rate adjustment instruction, and sending the overcurrent protection parameter to the level translator; the memory is used for storing at least two over-current protection parameters; and the level converter is used for setting an overcurrent protection function of the display panel according to the overcurrent protection parameter, so that the width of a detection window of the overcurrent protection function is adaptive to the pulse width of the vertical clock signal under the target refresh rate. Through the circuit, the technical problem that the design of a fixed overcurrent protection parameter is difficult to adapt to a display panel with a variable refresh rate is solved.

The invention relates to a flyback circuit over-current protection circuit realized based on an operational amplifier. The flyback circuit over-current protection circuit comprises a power supply driving module, an output voltage module, a current sampling module, a current comparison module and an over-current protection switch module. According to the circuit, a Hall sensor, a first operational amplifier chip U2, a first comparator U3 and a first triode Q2 are adopted for sequentially transmitting or processing signals, whether current exceeds a threshold value or not is judged through comparison, a result is fed back to a first driving chip U1, once the sampling current reaches a set value, a pin COMP of the first driving chip U1 is grounded through the first triode Q2, and the first driving chip U1 is driven by the first triode Q2. And the PWM waves are fed back to the first driving chip U1 and no longer output to drive the circuit to operate, so that the system can quickly achieve the purpose of protection instead of transferring the pressure to other devices. The whole circuit is simple in structure, timely in overcurrent protection, accurate in judgment and high in reliability, and can be widely applied to circuit scenes needing an auxiliary power supply with relatively high stability for power supply, such as solar inverters, smart home and other products.

The utility model relates to the converter field, and discloses an energy storage converter DC side over-current protection device comprising a base plate, the outer wall of the base plate is fixedly connected with a hydraulic cylinder, the output end of the hydraulic cylinder is fixedly provided with a rack, the lower surface of the rack is slidably connected to the upper surface of the base plate, the tooth end of the rack is engaged with a gear, and the gear is engaged with the hydraulic cylinder. A second swing rod is rotatably connected to the outer wall of the first swing rod, a supporting plate is rotatably connected to the outer wall of the second swing rod, the inner wall of the supporting plate is rotatably connected to the outer wall of the fixing rod, the lower surface of the sliding rail is fixedly connected to the upper surface of the bottom plate, and a dismounting assembly is arranged on the upper surface of the supporting plate. And the dismounting and mounting assembly is used for dismounting and mounting the converter. According to the utility model, the rack is pushed by the hydraulic cylinder to enable the gear to rotate, and the supporting plate is driven to lift by the second oscillating rod, so that the effect of facilitating circuit connection and fixation operation by installation personnel is achieved.

The utility model discloses an over-temperature and over-current protection circuit and a power adapter system, and the over-temperature and over-current protection circuit comprises an over-current monitoring assembly which is used for outputting a first fault signal lasting for a first preset time when the load voltage of a load circuit is greater than a set voltage. And the temperature control unit is used for outputting a second fault signal when the temperature of the load circuit exceeds the preset temperature threshold. And the first logic unit is electrically connected with the overcurrent monitoring assembly, the temperature control unit and the execution unit, and is used for controlling the execution unit to disconnect the load circuit when receiving the first fault signal and / or the second fault signal. And when the first logic unit receives the first recovery signal and / or the second recovery signal, the execution unit is controlled to close the load circuit again. The over-temperature and over-current protection circuit can prevent the load circuit from being disconnected for a long time in the over-temperature and over-current protection process.

The invention discloses a current fault detection circuit and device, a storage medium and a program product, and relates to the technical field of current detection, an external detection resistor and a related conditioning circuit can be omitted by directly utilizing a CS pin signal of a power supply module and introducing a dynamic threshold generation module, the response speed is increased, and the reliability is improved. And the system power consumption, the cost and the PCB area are reduced. Meanwhile, the design reduces a current detection link, and can greatly improve the response speed of overcurrent protection. Besides, the dynamic threshold value can be intelligently adjusted according to the power model, the temperature and the load change, so that more accurate fault judgment can be realized, false triggering and leakage protection are effectively avoided, and the reliability and the safety of the system are fundamentally enhanced.

The invention provides an arc suppression coil grounding system zero-sequence overcurrent protection method based on zero-sequence voltage verification. The protection reliability is improved through multi-criterion fusion. The method specifically comprises the following steps: S1, arc suppression coil system fault starting criterion: monitoring a zero sequence voltage in real time, and triggering a protection algorithm when the amplitude of the zero sequence voltage exceeds a preset threshold value; s2, fault time calculation: calculating the duration time of a grounding fault based on the duration characteristic of the zero-sequence voltage; s3, fault position discrimination: in combination with the amplitude characteristics of the zero-sequence current, distinguishing an internal fault from an external fault; and S4, intelligent comprehensive decision making: fusing the transient and steady state characteristic quantities of the zero-sequence voltage and the zero-sequence current, and generating a protection action signal. According to the invention, by dynamically checking the correlation characteristics of the zero-sequence voltage and current, the problems of insufficient sensitivity and high maloperation rate of the traditional zero-sequence overcurrent protection in the arc suppression coil grounding system are effectively solved.

The invention discloses a detection and protection circuit system of an amplifier, which is characterized in that a protection circuit system consisting of an over-temperature protection circuit (OTP), an over-current protection circuit (OCP), an over-voltage protection circuit (OVP), an electromagnetic interference (EMI) protection circuit and an ESD protection circuit is used, and a band-gap reference circuit BG and the over-temperature protection circuit are connected in series to form a whole which is connected in parallel with a core of the amplifier; meanwhile, the overcurrent protection circuit is connected to the output end of the amplifier in parallel, the overvoltage protection circuit is connected with the electromagnetic interference protection circuit in series and arranged at the input end of the amplifier, and the ESD protection circuit is connected with the power port in series. The over-temperature protection circuit mainly aims at an output heat source power tube and an input heat source differential pair. The over-current protection is to protect the output power tube, and if the over-temperature protection is triggered, the FLAG outputs an over-temperature protection signal. And the ESD protection is used for protecting electrostatic discharge of IO and POWER ports.

The invention discloses an impact load flexible starting method for a bidirectional off-grid and grid-connected energy storage inverter, and the method comprises the steps: collecting an output current of the bidirectional off-grid and grid-connected energy storage inverter to obtain a target current if a load connected with the bidirectional off-grid and grid-connected energy storage inverter is detected to be started; if the target current is greater than or equal to a preset current threshold value, taking a first preset PI controller as a target controller; obtaining a correction parameter of a modulation wave amplitude output by the target controller, and generating a control signal based on the correction parameter of the modulation wave amplitude; and controlling the bidirectional off-grid and grid-connected energy storage inverter based on the control signal so as to realize flexible starting. According to the invention, the output voltage can be reduced when the load is started, so that overcurrent and overpower are avoided, and overload or overcurrent protection can be avoided.

The invention relates to the technical field of power supplies, and discloses a motor controller driving power supply and a control method, the driving power supply comprises a main controller, a power supply management unit, a plurality of overcurrent protection circuits, an upper bridge driving power supply circuit and a lower bridge driving power supply circuit; wherein the main controller is respectively connected with the power management unit, the plurality of overcurrent protection circuits, the upper bridge driving power supply circuit and the lower bridge driving power supply circuit; the input end of the power management unit is connected with an input power supply, and the output end of the power management unit is respectively connected with the plurality of overcurrent protection circuits; and the output ends of the plurality of overcurrent protection circuits are respectively connected with each bridge arm circuit in the upper bridge driving power supply circuit and the lower bridge driving power supply circuit, so that the main controller controls and outputs a plurality of paths of independent driving power supplies. The motor controller driving power supply is provided with a plurality of paths of independent driving power supplies, so that the upper three-bridge-arm and lower three-bridge-arm six-path driving power supplies of the upper bridge driving power supply circuit and the lower bridge driving power supply circuit independently control power supply and do not interfere with each other.

The utility model relates to a kind of compressor inverter overcurrent protection circuit and air conditioner, belong to air conditioning technical field, including rectifier unit, sampling resistance, main control chip, overcurrent protection control switch, fault state self-locking maintenance switch, operational amplifier and voltage comparator.Sampling resistance gathers DC bus voltage signal, after amplification by operational amplifier, it is transmitted to the analog-digital conversion pin and voltage comparator of main control chip.Signal is compared with preset threshold by voltage comparator, low level is output when over threshold, makes overcurrent protection control switch open, rectifier unit is disabled;While fault state self-locking maintenance switch is turned on, and fault pin is locked as low level, realizes overcurrent protection and self-locking.The circuit cooperates by hardware and software, quickly responds overcurrent fault and prevents false restart, improves the security and reliability of air conditioning system.

The invention discloses an overcurrent protection circuit and an overcurrent protection method. In the overcurrent protection circuit, a temperature acquisition unit acquires the environment temperature of an environment where a switch element is located, and sends the environment temperature to a calculation unit; the current acquisition unit acquires an actual current value flowing through the switch element and sends the actual current value to the calculation unit; after receiving the environment temperature and the actual current value, the calculation unit compensates the actual current value by using the environment temperature to obtain a compensation current value, and generates an overcurrent protection signal when the compensation current value is greater than an overcurrent protection threshold value; and the driving unit is connected with the calculation unit, and the driver drives the switching element to be switched off based on the overcurrent protection signal after receiving the overcurrent protection signal sent by the calculation unit. According to the invention, the technical problems that the collected current is inaccurate and fault false alarm or missing alarm is easily caused due to the fact that the conduction impedance of the high-side driving switch is greatly influenced by the temperature in the prior art are solved.