184 results about "Limiting current" patented technology

The invention relates to the technical field of charging optimization, and discloses a multi-stage charging optimization method based on adaptive identification of a battery, and the method comprises the following steps: S101, in-situ detection and battery type identification; step S102, applying a current step and collecting a voltage response; s103, predicting the change of the terminal voltage along with time; step S104, determining a safe amplitude limiting current; step S105, determining a pre-deceleration factor; and step S106, judging full power, generating a quota recovery instruction, and returning to the step S104 for redistribution. Battery individual parameters are obtained through in-situ detection and micro-pulse identification, current quotas are dynamically distributed based on a constant voltage proportion, a safe target current is determined by combining voltage and power amplitude limiting, current distribution unbalance is avoided, the bus current utilization rate is maximized, voltage overshoot is inhibited by means of a first-order following strategy and a pre-deceleration factor, and the safety of a battery is improved. And stable switching is ensured by matching with constant-voltage inlet current clamping.

The invention discloses a network construction converter virtual impedance and power reference cooperative adjustment method and system, and relates to the technical field of power control, a virtual synchronous generator system introduces virtual impedance to increase equivalent output impedance of an inverter, and an internal voltage reference generated by a virtual synchronous generator algorithm of the inverter is monitored in real time; monitoring the local voltage measured by the common coupling point in real time; based on the vector difference between the internal voltage reference and the local voltage, the accurate amplitude of the virtual impedance is solved in real time by combining the maximum current limit value of the power electronic device; and determining a function relationship between an active power reference value and reactive power based on the accurate amplitude of the virtual impedance, monitoring the reactive power measured at the common coupling point in real time, and adjusting the active power reference value according to the function relationship to keep a stable balance point. And virtual impedance is dynamically calculated to accurately limit current, and active power reference is adaptively adjusted according to real-time reactive response, so that maximized power grid support and safe and stable operation of the converter are realized.

The invention discloses a high-efficiency current amplification circuit based on H-bridge structural design, the current amplification circuit comprises a power supply module, two control modules, an H-bridge amplification module, a logic control module, a protection module and a load module, the power supply module is used for providing a direct current input voltage, each control module comprises a half-bridge controller, two resistors and two capacitors, and the logic control module is connected with the H-bridge amplification module. Pins of each half-bridge controller are set to be a VCC end, an IN end, an SD end, a COM end, a VB end, an HO end, a VS end and an LO end, and the two resistors are used for limiting current and adjusting voltage. The H-bridge structure is cooperated with the IRF540N MOS tube, high voltage, large current output, multiple protection and redundancy design are realized, long-term stable operation in an industrial environment is ensured, general elements and a modular architecture are adopted, the purchase and maintenance cost is reduced, and by adjusting the capacitance value of a capacitor, the resistance value of a resistor or the model of the MOS tube, the device can be expanded to scenes with higher power or different voltages.

The invention discloses a quick charging safety control method for a mobile power supply, and particularly relates to the technical field of charging control of an electrochemical energy storage device. The method is started when a charging adapter is connected after the mobile power supply completes high-power discharging, and an ion relaxation index is obtained through open circuit detection; entering rhythm cycle control of charging-charging stopping-measuring, and limiting current according to risk levels; the charging current and the charging stopping duration are adjusted in a self-adaptive mode according to the ion relaxation index and the terminal voltage change rate in the circulation, finally, when the index is stabilized within the safety range, the constant-current and constant-voltage charging stage is smoothly switched, and safety control over rapid charging is achieved; according to the method, the distribution state of the battery cell ions is accurately detected before charging, current is limited in a graded mode according to risk grades in rhythm slow start, dynamic optimization of the charging current and the charging stopping duration is achieved in combination with self-adaptive adjustment, a constant current stage and a constant voltage stage are smoothly switched to when the state is stable, and safety and efficiency are both considered in the whole process.

A bridgeless power factor correction (PFC) circuit for reducing electromagnetic interference (EMI) is disclosed herein. A current source is placed in parallel with a switch of a low frequency leg. The current source may be turned on during zero crossings of the AC input voltage to limit current and reduce the rate of change in voltage. In turn, EMI may be advantageously reduced without the need for large passive filters or complicated circuitry.

The invention discloses a rechargeable battery management system based on negative side current limiting, and the system comprises a power circuit which comprises a positive bus, a negative bus, and a battery interface and an equipment interface which are disposed at the two ends of the positive bus and the negative bus; the charging switch and the discharging switch are connected to the negative bus in series; the detection circuit is used for detecting state parameters of the battery and / or the power supply loop; one end of the current limiting circuit is electrically connected with a node between the charging switch and the discharging switch, and the other end of the current limiting circuit is electrically connected with the negative electrode end of the equipment interface; and the controller is electrically connected with the charging switch, the discharging switch, the current limiting module and the detection circuit, and is used for controlling the current limiting module to access or exit from the power supply loop according to the state parameters detected by the detection circuit. According to the battery management system, the current limiting circuit is arranged on the cathode bus side, and the cooperative work of the detection circuit and the controller is combined, so that the accurate dynamic control of the current of a power supply loop is realized, and the limitation of a traditional hardware current limiting scheme is overcome.

Provided is a power supply control device provided in a switching power supply apparatus that converts an input voltage into an output voltage through switching of an output transistor, including a switching control circuit that stabilizes the output voltage by switching control of the output transistor, based on a feedback voltage corresponding to the output voltage, a signal output terminal, and a signal output circuit that is capable of outputting a signal corresponding to whether the output voltage is normal from the signal output terminal, based on the feedback voltage, the switching control circuit being capable of performing an overcurrent protecting operation that limits a current flowing through the output transistor to a limit current or less, and the signal output circuit outputting a specific signal indicating execution of the overcurrent protecting operation from the signal output terminal when the current flowing through the output transistor reaches the limit current.

The invention discloses an integrated circuit magnetic field auxiliary electroplating system which comprises electroplating equipment provided with a cathode assembly and an anode assembly which are opposite to each other; the magnetic field generator comprises a magnet N pole and a magnet S pole, the magnet N pole is arranged on one side of an anode assembly of the electroplating equipment, the magnet S pole is arranged on one side of a cathode assembly of the electroplating equipment, and the magnetic field generator generates a transverse magnetic field between the cathode assembly and the anode assembly. The invention belongs to the field of micro rapid prototyping processing, and particularly relates to a magnetic field auxiliary electroplating system for an integrated circuit. The transverse magnetic field is applied to adjust the electric field through the magnetic force, and according to the electromagnetic induction principle and the Larentz force law, liquid phase mass transfer is accelerated, the deposition speed and the limiting current density are improved, the time of reaction bubbles staying on the deposition surface is shortened, grains are refined, and the deposition quality is improved.

The invention discloses a Ru / Ni-3DONMC catalyst as well as a preparation method and application thereof, and relates to the technical field of new energy materials and electrochemical catalysis. According to the invention, self-designed ordered SiO2 microspheres are self-assembled as a template, a nitrogen-doped carbon carrier with a three-dimensional ordered hierarchical pore structure is constructed, and a composite catalytic system with a multi-stage active center is successfully prepared by combining a bimetallic precursor adsorption impregnation and thermal reduction process. The catalyst disclosed by the invention shows excellent bifunctional catalytic performance in an alkaline medium; only 16 mV overpotential is needed in a hydrogen evolution reaction under the current density of 10 mA cm <-2 >, and the Tafel slope is as low as 40.54 mV / dec; and in a hydroxide reaction, the material has high limiting current density of 2.55 mA cm <-2 > and excellent mass activity. And it is powerfully proved that the intrinsic catalytic activity and long-term operation stability of the hydrogen-electricity reaction can be effectively improved through a monatomic-nanocluster cooperative regulation strategy.

The invention discloses a current limiting method and system for a virtual synchronous generator after a power grid fault. The method comprises the following steps: monitoring a ratio of a power grid voltage to a rated voltage; comparing the ratio with a voltage drop degree threshold value; when the ratio is smaller than a voltage drop degree threshold value, a fault current limiting strategy is started; when a current-limiting strategy stopping condition is reached, judging whether the amplitude of the power grid current is smaller than or equal to a current-limiting threshold value or not; if the amplitude of the power grid current is smaller than or equal to the current limiting threshold value, ending, otherwise, carrying out the fault current limiting strategy again; when the ratio is greater than or equal to the voltage drop degree threshold value, the fault current limiting strategy does not need to be started; wherein the fault current limiting strategy comprises an active ring adjustment strategy based on angular frequency deviation feedback and a reactive adjustment strategy based on an adaptive adjustment reactive droop coefficient. According to the invention, the response capability and the operation stability of the converter during sudden power grid disturbance can be improved.

The invention relates to the technical field of fuel cell monitoring and life prediction, in particular to a fuel cell life prediction method combining mechanism and data driving, which comprises the following steps: calculating reversible potential of a fuel cell through a Nernst equation, and establishing a theoretical output voltage model by combining three voltage losses of activation, concentration difference and ohm; acquiring historical data of voltage attenuation under actual operation conditions, and determining a life end voltage threshold value; training historical data by using a time sequence algorithm, identifying an aging rule function of key parameters (ohmic impedance, hydrogen permeation current density, exchange current density and limiting current density), and evaluating parameter identification precision through RMSE; and substituting the parameter aging function into the voltage model to predict future voltage, and when a predicted value is lower than a life end threshold for the first time, calculating the remaining service life. According to the method, the electrochemical mechanism and the data driving technology are fused, and the prediction accuracy is remarkably improved.

The application belongs to the field of fuel cells, and particularly relates to a preparation method of a single-iron atom catalyst. A solution containing component A, component B and component C is subjected to a coprecipitation reaction to obtain a precipitate; the precipitate is aged in a component D solution to obtain an aged product; and the aged product is subjected to gradient calcination to obtain the single-iron atom catalyst. The component A contains a compound of formula 1; the component B contains at least one of iron cyanide, dopamine and a salt thereof; the component C contains an iron source and a zinc source; and the component D contains a water-soluble compound having a fragment of formula 3. The application also discloses a material prepared by the method and an application of the material in ORR and fuel cells. Research shows that the material prepared by the method has excellent catalytic activity and stability in ORR, and a metal-air battery assembled by using the material can have excellent limiting current density, peak power and discharge specific capacity.

The invention discloses a charging efficiency adjusting method, a controller and an energy storage device, and the method comprises the steps: determining a charging limiting current according to a charging voltage, a charging current and a charging cut-off voltage when the energy storage device is in a charging state; and determining a charging demand current based on the charging preset current, the charging limit current and the electric quantity value, wherein the charging demand current is used for indicating the charging current output to the energy storage device by the charger. The invention aims to solve the problem of how to further shorten the charging time.

The application provides a starting method of an asynchronous generator, comprising the steps of: setting an auxiliary AC power supply; connecting the auxiliary AC power supply and a pre-charging loop of an AIM active interface module to limit current, rectifying by an ALM active power module and pre-charging a DC bus; connecting the auxiliary AC power supply and a main loop of the AIM active interface module, disconnecting the auxiliary AC power supply and the pre-charging loop of the AIM active interface module, rectifying by the ALM active power module and supplying power to the DC bus; starting the asynchronous generator by using the excitation energy provided by the DC bus; starting the ALM active power module and the AIM active interface module by using the electric energy generated by the asynchronous generator; disconnecting the auxiliary AC power supply and the main loop of the AIM active interface module, and connecting the main loop of the AIM active interface module and a power grid. The starting method can start the asynchronous generator without the power grid being powered. The application also provides a frequency converter system using the starting method.

Circuit embodiments for a switched-capacitor power converter, and / or methods of operation of such a converter, that robustly deal with various startup scenarios, are efficient and low cost, and have quick startup times to steady-state converter operation. Embodiments prevent full charge pump capacitor discharge during shutdown of a converter and / or rebalance charge pump capacitors during a startup period before switching operation by discharging and / or precharging the charge pump capacitors. Embodiments may include a dedicated rebalancer circuit that includes a voltage sensing circuit coupled to an output voltage of a converter, and a balance circuit configured to charge or discharge each charge pump capacitor towards a target steady-state multiple of the output voltage of the converter as a function of an output signal from the voltage sensing circuit indicative of the output voltage. Embodiments prevent or limit current in-rush to a converter during a startup state.

According to one embodiment, an electronic circuitry comprises a first transistor connected between an input voltage line and an output terminal, an input voltage being supplied to the input voltage line; and a current limiting circuit configured to limit an output current of the first transistor to a limiting current or less by restricting a variable range of a drive voltage of the first transistor within a predetermined range, the limiting current being determined by a reference voltage having a dependency on the input voltage.

The invention discloses a fast charging tail end current limiting method based on a BMS. The fast charging tail end current limiting method comprises the steps that a whole pack is charged to a first constant current charging upper limit SOC through first constant current; the method comprises the following steps: defining a gradient current-reducing charging SOC interval = (a first constant-current charging upper limit SOC and a second constant-current charging lower limit SOC), dividing the gradient current-reducing charging SOC interval into a plurality of continuously rising SOC sub-intervals, searching a constant-current charging voltage corresponding to the upper limit SOC of the SOC sub-interval in a charging CCV table according to a current charging current for the SOC sub-interval where the current SOC of the whole pack is located, and calculating a constant-current charging voltage corresponding to the upper limit SOC of the SOC sub-interval according to the constant-current charging voltage. If the maximum single voltage of the whole pack is larger than the constant-current charging voltage corresponding to the upper limit SOC of the SOC sub-interval in the charging CCV table, the current charging current is adjusted to the charging current corresponding to the next higher SOC sub-interval in the charging CCV table; and charging the whole pack to be fully charged by adopting second constant current. According to the invention, balance between safe charging and rapid charging is realized at the same time.

An insulation and voltage resistance detection circuit comprises an input port which is connected with a rectifier diode through a resistance network and is used for carrying out current limiting and voltage dividing processing on an input signal; the rectifying circuit is used for carrying out full-wave rectification on an input signal by utilizing a plurality of diodes and outputting stable direct-current voltage; the filter circuit comprises a plurality of filter capacitors and is used for carrying out smooth filtering on the rectified direct-current voltage and providing stable output voltage; the optical coupler U1 is used for realizing electrical isolation between an input signal and an output power supply and avoiding high-voltage or noise conduction; the current limiting circuit comprises a current limiting resistor and is used for controlling the current passing through the optocoupler or the LED and protecting the device; by introducing a multi-stage resistor current limiting circuit, a diode rectification circuit, a filter capacitor circuit and an optical coupler isolation circuit, efficient power supply control is realized.

A driver circuit includes a primary driver sub-circuit, a comparator sub-circuit and an auxiliary driver sub-circuit. The primary driver sub-circuit is configured to (i) generate an output voltage, and (ii) supply a predetermined maximum amount of current from a power source to a load via a first switch. The comparator sub-circuit is configured to (i) detect when a high-power dissipation condition exists which could lead to overheating the primary driver sub-circuit, and (ii) based on detection of the condition, generate a first output signal. The auxiliary driver sub-circuit is configured to, based on the first output signal, transition between (i) pulling-up the output voltage to the source voltage and supplying current from the power source to the load, and (ii) decreasing an amount of current being supplied to the load.

The invention discloses a charging system for power management, and belongs to the technical field of power management. Comprising a first limiting element, and the input end of the first limiting element is connected with a voltage bus and used for limiting current flowing into the power management chip from the voltage bus; the power management chip is provided with a charging circuit, the charging circuit comprises a driving circuit, and the input end of the driving circuit is connected with a first limiting element; and the first power tube is arranged outside the power management chip, the drain electrode of the first power tube is connected with the voltage bus, and the grid electrode of the first power tube is connected with the output end of the driving circuit. The technical scheme has the beneficial effects that the power tube bearing withstand voltage is placed outside the power management chip, the low-voltage device is still adopted in the power management chip, a special process is not needed in the production process, and the cost is reduced.

A high-load cobalt-based single-atom catalyst for oxygen reduction and its preparation method are disclosed, belonging to the field of electrocatalysis technology. This method utilizes the cage structure in ZnCo-ZIF to encapsulate nitrogen-rich metal molecules, followed by high-temperature carbonization under nitrogen conditions to obtain the catalyst. Benefiting from the separating effect of Zn metal nodes in ZIF and the spatial confinement effect of the ZIF cages, as well as the high nitrogen content in the guest molecule, a cobalt-based single-atom catalyst with a loading of 4.0 wt% was prepared. Furthermore, compared to traditional preparation methods, the catalyst prepared using a mixed solvent exhibits a small particle size, resulting in a high specific surface area that fully exposes the active sites. The large specific surface area allows for the full exposure of the high-load metal atom active sites, thus demonstrating excellent performance in the oxygen reduction reaction, with a half-wave potential of 0.88 V and a limiting current density of 6.0 mA·cm⁻¹ in 0.1 M KOH electrolyte. ‑2 .

The invention discloses an air conditioner control method, device and system and an air conditioner, and belongs to the field of air conditioner control. The air conditioner control method comprises the steps that when power is cut off and powered on again during operation, whether the air conditioner enters a power correction mode or not is determined based on the operation mode of the air conditioner, the outdoor environment temperature and the actual current; when a power correction mode is entered, limiting current is determined based on the current outage frequency and the effective current, and the limiting current is smaller than the effective current; and finally, the air conditioner is controlled to start and operate, and the actual current is controlled to be limiting current. According to the scheme, whether the air conditioner enters the power correction mode or not can be determined based on actual requirements when the air conditioner is powered off and powered on again during operation, and after the air conditioner enters the power correction mode, the actual current of the air conditioner is actively reduced so as to limit the operation power and reduce the probability of power tripping caused by short-time large-load operation; and the intelligent use satisfaction degree of a user on the air conditioner is improved, and the competitiveness of brand products is kept.

The invention relates to the technical field of photovoltaic power generation, and discloses a current and voltage characteristic curve generation method and device, electronic equipment and a storage medium, and the method comprises the steps: obtaining a historical maximum power point voltage value of a target photovoltaic array; based on the historical maximum power point voltage value, determining a maximum power point current value corresponding to the historical maximum power point at the current moment; determining a scanning upper limit current value based on the maximum power point current value; acquiring a scanning lower limit current value; and performing current scanning on the target photovoltaic array based on the scanning upper limit current value and the scanning lower limit current value to obtain a plurality of current and voltage data pairs of the target photovoltaic array so as to generate a target current and voltage characteristic curve of the target photovoltaic array. The corresponding scanning upper limit current value is determined according to the current working condition of the photovoltaic array, the accuracy of the generated IV characteristic curve is improved, and the safety of the photovoltaic array is improved.

A connection circuit for a field device comprises two connections forming a two-wire interface, a microcontroller for operating the field device, a voltage converter connected upstream of the microcontroller and configured to operate the microcontroller with an operating voltage, a supply capacitor connected upstream of the voltage converter and configured to absorb electrical energy when the connection circuit is started and to use it to supply the voltage converter, a first current limiting element connected upstream of the supply capacitor and designed to limit an input current below a permissible limit current when starting the connection circuit, a first bridging element connected in parallel with the first current limiting element and configured to bridge the first current limiting element if a first criterion is satisfied, and a test element configured to check whether the first criterion is satisfied.

A plurality of DC power supply apparatuses which are CVCC power supplies have output sides connected in parallel to a load. In each of the plurality of DC power supply apparatuses, an upper limit current maintained in a CC mode is designed to be equal to or lower than a rated current. Output voltages from the plurality of DC power supply apparatuses are actually different from equivalently set reference voltages Vr, due to variation within an allowable voltage range of the load 120. The plurality of DC power supply apparatuses operate to supply currents, as being accompanied by transition from a CV mode to the CC mode, sequentially in the descending order of magnitude of actual output voltages thereof, with increase in output current to the load.

The application provides a DC-DC circuit and a power control method thereof. The method comprises the following steps: after detecting that an output end of the DC-DC circuit is connected to a charged device, requesting a maximum bearing voltage and a maximum bearing current from the charged device, until obtaining the maximum bearing voltage at a first time, calculating a limit current by taking a ratio of a test upper limit power and the maximum bearing voltage; during a period from a time when the charged device is connected to the first time: maintaining an output voltage at a default voltage, and maintaining an output current below a default current; during a period from the first time to a set time: maintaining the output voltage at the maximum bearing voltage, and maintaining the output current to be greater than the test upper limit current and below the maximum bearing current; after the set time: maintaining the output voltage at the maximum bearing voltage, and maintaining the output current below a smaller one of the test upper limit current and the limit current.

A sensor element includes an element body, at least one adjustment pump cell having an inner electrode disposed in an oxygen concentration adjustment chamber, a measurement electrode, a diffusion rate-limiting section. A height t [mm] of the diffusion rate-limiting section, obtained based on the following parameters: a path length L [cm] of the diffusion rate-limiting section; a width H [cm] of the diffusion rate-limiting section; a limiting current Ip [A] of the adjustment pump cell; the Faraday constant F [A·sec / mol]; the diffusion coefficient D [cm2 / sec] of oxygen; the gas constant R [cm3·atm / mol·K]; a temperature T [K] of the inner electrode; an oxygen partial pressure Poe [atm] in the measurement gas; and an oxygen partial pressure Pod [atm] in the oxygen concentration adjustment chamber, is 0.0035 or greater.

The embodiment of the invention provides a detection method of a thermal overload protector, and relates to the technical field of thermal overload. The method comprises the following steps: sampling a thermal overload protector to-be-detected set to obtain a plurality of thermal overload protector samples, and obtaining test tripping time corresponding to each thermal overload protector sample; determining the tripping hot bending deflection corresponding to each thermal overload protector sample; according to a first hot bending deflection corresponding to a predetermined action range lower limit current, a second hot bending deflection corresponding to an action range upper limit current and tripping hot bending deflections corresponding to the plurality of thermal overload protector samples, determining a process capability index corresponding to the thermal overload protector samples; and determining the process capability of the thermal overload protector according to the process capability index corresponding to the thermal overload protector sample. The embodiment of the invention is used for providing a technical scheme which avoids the problem of high cost caused by full inspection and can realize effective quality control.

The present invention belongs to the field of electrocatalysis technology and relates to the application of a bismuth molybdate-based composite electrode material in hydrogen evolution reaction, oxygen evolution reaction and oxygen reduction reaction. The composite electrode material is: NiO / Bi2Mo x W 1‑x O6, where 0 ≤ x ≤ 1. The present invention first applies the composite electrode material to electrocatalytic hydrogen evolution reaction, oxygen evolution reaction and oxygen reduction reaction; the oxygen reduction reaction kinetics shows a four-electron transfer pathway, the hydrogen evolution reaction and oxygen evolution reaction have the lowest overpotential, and the oxygen reduction reaction has the largest half-wave potential and limiting current density; compared with the monomer, the composite material has excellent electrocatalytic performance and good application prospects, and will not cause secondary pollution to the environment during the application process; in addition, after 24 h of cyclic stability test, the oxygen reduction reaction of the composite electrode material is very stable.

The present disclosure relates to apparatuses and methods for limiting current. An apparatus for limiting current includes a differential amplifier configured to equalize a voltage across a power transistor and a sense transistor and a regulation circuit of an output current of the apparatus for limiting the current. The regulation circuit includes a transconductance amplifier configured to limit the output current when an output potential of the differential amplifier is higher than or equal to a reference potential proportional to a reference current, the value of the reference current being equal to I LIMIT / (N.M), where I LIMIT corresponds to a current limit value, N corresponds to a width-to-length ratio between the power transistor and the sense transistor, and M corresponds to a width-to-length ratio between transistors of a current mirror coupled to the sense transistor.