22 results about "Limiting current" patented technology

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 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.

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.

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.

A method and apparatus, a controller, a fuel cell system, and a program product for limiting current are disclosed. The method includes (i) determining the power of a hydrogen circulating pump in a fuel cell system, (ii) determining a current limiting adjustment parameter based on the power of the hydrogen circulating pump, wherein the current limiting adjustment parameter is inversely proportional to the power of the hydrogen circulating pump, and (iii) adjusting a current limiting value of a DC-DC converter in the fuel cell system according to the determined current limiting adjustment parameter, wherein the current limiting value is directly proportional to the current limiting adjustment parameter. The method uses the power of the hydrogen circulating pump to judge whether the fuel cell system is flooded, thereby adjusting the current limiting value of the DC-DC converter to maintain the normal operation of the fuel cell system when hydrogen is insufficient.

This invention discloses a testing method for lithium battery characteristics, belonging to the field of lithium battery testing technology. The method includes: selecting a test equipment group according to the lithium battery model and specifications, and performing status checks and calibration; setting the charging / discharging current or power, charging / discharging time, target temperature, and target voltage based on the nominal capacity of the lithium battery; at the end of charging / discharging, iteratively adjusting the current or power using a binary method based on the comparison between the actual voltage and the target voltage; the test equipment group collecting voltage, current or power, time, and environmental information and performing data analysis; thereby determining the limiting current value or limiting power value of the lithium battery, and calculating the average value and standard deviation. This invention can improve the accuracy, consistency, and automation of lithium battery limiting charge / discharge capability testing, while also ensuring testing safety and reliability.

The present application relates to a kind of test circuit of memristor, belong to the technical field of test of memristor.The present application discloses a kind of test circuit of memristor, including voltage source module 1, constant current source module 2, analog switch 3, sampling resistance 4, current-limiting judging module 5, memristor 6 and auxiliary measurement acquisition module 7, with the following advantages:(1) the test instrument of the test circuit of memristor is small and portable, can verify device immediately;(2) limiting current can reach microampere level, can reach smaller limiting current value, and can detect current value in real time;(3) the resistance range of detection is large, can cover most use scenarios, can be extended into two-end device IV curve measurement;(4) compared with large instrument, cost is lower.

This invention provides a battery system that can suppress the deposition of lithium metal during charging of a lithium-ion secondary battery, even if the lithium-ion secondary battery has degraded. [Solution] The battery system comprises a battery 80 made of a lithium-ion secondary battery, a group of sensors 90 that detect the voltage, current, and temperature of the battery 80, and a control device 100 that controls the charging current of the battery 80 based on the values ​​detected by the group of sensors 90. The control device 100 acquires the degradation state of the battery 80 from the values ​​detected by the group of sensors 90 and sets a threshold voltage for which lithium metal is deposited on the electrodes of the lithium-ion secondary battery with respect to the voltage of the battery 80, according to the acquired degradation state of the battery 80. If the voltage of the battery 80 exceeds the threshold voltage during charging of the battery 80, the control device 100 reduces the charging current to a limiting current.

A kind of 3D printing shape electrode-based precision polishing method of additive manufacturing metal micro inner runner, it relates to a kind of polishing method of additive manufacturing metal micro inner runner.The present application is to solve the technical problems that the current additive manufacturing metal micro runner inner surface finishing process is easy to cause polishing uneven, micro crack and other defects.The present application carries out overvoltage electrochemical polishing under the voltage higher than the limit current platform voltage value, can quickly remove the protrusion of micro runner outer surface, then replace titanium mesh electrode with 3D printing preparation shape electrode, place shape electrode into the inside of additive manufacturing metal micro runner, then apply a voltage higher than the polishing voltage of step one to carry out overvoltage electrochemical polishing based on 3D printing shape electrode, and excellent inner surface and outer surface quality are obtained.

This invention discloses a method for melting homogeneous ultra-high strength titanium alloy ingots, belonging to the field of titanium alloy technology. To ensure the uniformity of elements in the ultra-high strength titanium alloy ingots, this invention provides a method for melting homogeneous ultra-high strength titanium alloy ingots, comprising: electrode block thickness H and pressing density ρ satisfying H≤k / (ρ-ρ0), welding to obtain a consumable electrode; the consumable electrode undergoes three melting processes, with the current I2 in the stable melting stage of the second melting process satisfying: I2≥α×I1, I2≥β×I ‑ The rated value is ≥10 min for the third melting and feeding process, and the melting current decrease rate is >1.2 kA / min. This invention ensures the stability of the consumable electrode during the first melting by controlling the particle size of the raw materials and designing the electrode block thickness; the second melting process uses an ultra-high limiting current process to reduce inclusion defects; and the third melting process uses an ultra-fast current interruption feeding process to make the ingot composition uniform, resulting in a high-quality, homogeneous, ultra-high-strength titanium alloy ingot.

The application discloses a bridge arm current distribution method and system for reducing M3C bridge arm current peak value, comprising the following steps: constructing a current distribution model based on the relationship between the power frequency side line current, the frequency division side line current and the bridge arm current; optimizing the current distribution model based on the concept of sub-converter upper limit current; obtaining the selection principle of positive sequence current distribution coefficient based on the optimized current distribution model; proposing a solving method of the positive sequence current distribution coefficient with the minimum sub-converter upper limit current as the target based on the selection principle of the positive sequence current distribution coefficient; designing the solving process of the positive sequence current distribution coefficient in actual application based on the solving method of the positive sequence current distribution coefficient with the minimum sub-converter upper limit current as the target, obtaining the positive sequence current distribution coefficient, and determining the distribution scheme of each bridge arm current. The application can effectively reduce the bridge arm current peak value, significantly improve the overload capacity of the M3C converter station, reduce the investment and construction cost of the M3C converter station, and improve the economy of the whole system.

This application relates to the field of motor control technology and discloses a motor control method and system. The motor control method includes: upon detecting an AC zero-crossing, determining the electrical angle increment of the motor relative to the previous AC zero-crossing; determining the electrical angle of the current AC zero-crossing based on the electrical angle of the previous AC zero-crossing and the electrical angle increment; determining the target phase path that needs to be turned on based on the comparison results of the electrical angle of the current AC zero-crossing with multiple conduction control intervals; and controlling the target phase path to be turned on at the current AC zero-crossing. This motor control method, through precise electrical angle tracking and zero-crossing synchronized phase-by-phase conduction control, can reduce the instantaneous current during motor startup, effectively limit current surges, alleviate transient stress on channel devices, lines, and the load body, and achieve soft starting of the motor.

This invention discloses a charging control method, device, charger, and electric mobility scooter. The method includes: configuring the maximum current value of the target battery when the charger is electrically connected to the target battery; acquiring the current temperature value of the charger; determining the current ideal charging current value based on the current temperature value and a preset maximum operating temperature threshold; determining the target charging current value based on the battery's maximum current value, the ideal charging current value, and a preset maximum charging current value; and performing closed-loop control of the charging current output by the charger based on the target charging current value. This invention enables the charger to continuously output a maximum current based on the highest operating temperature while ensuring charging safety, thereby shortening the charging time.

An arc mitigation apparatus includes an arc mitigation device and a solar cell. The arc mitigation device is configured to be mounted to a low-, medium-, or high-voltage switchgear. The arc mitigation device is configured to stop or limit current flow within at least one part of the low-, medium-, or high-switchgear when activated. The solar-cell is configured to be located within a compartment of the low-, medium-, or high-voltage switchgear. The solar-cell is configured to cause the arc mitigation device to activate due to radiation from an electrical arc of the switchgear impinging upon the solar-cell.

A control circuit with a slow-start switch includes a power supply, a post-stage load and an MCU for outputting a control voltage for activating the control circuit. The power supply is a constant-voltage power supply and is controllably coupled to the post-stage load through a delay switch and a current limiting module. The delay switch is a normally-open switch. The current limiting module is configured to be enabled when the control voltage is outputted by the MCU under power-on of the power supply and to be automatically disabled when the delay switch is turned on. A limiting current I3 of the current limiting module to the post-stage load is less than or equal to a minimum value of an anti-surge current I1 of the power supply and an anti-surge current I2 of the delay switch.

Provided is a power supply control device provided in a switching power supply apparatus configured to convert an input voltage into an output voltage through switching of an output transistor, the power supply control device including a switching control circuit configured to stabilize the output voltage by performing switching control of the output transistor, based on a feedback voltage corresponding to the output voltage, and a temperature detecting circuit configured to detect a target temperature within the power supply control device and output a signal indicating a result of the detection of the target temperature to the switching control circuit, the switching control circuit being configured to be capable of performing an overcurrent protecting operation that limits a current flowing through the output transistor to a limit current or less, and the switching control circuit adjusting the limit current according to the target temperature.

The embodiment of the present application discloses a kind of calibration methods for proportional valve, which comprises the following steps: determining proportional valve opening current according to dichotomy;Proportional valve current range is determined according to the proportional valve opening current and proportional valve limit current, wherein proportional valve opening current < proportional valve limit current;Obtain several current values and its corresponding flow values in the proportional valve current range;When the several current values and its corresponding flow values meet monotony, calibration is completed, this calibration method determines proportional valve opening current by dichotomy, overcomes the problem that calibration time is too long due to the difference between valve characteristics, and judges whether current values and its corresponding flow values meet monotony, solves the calibration error problem caused by the difference of proportional valve characteristic curve, and improves the pass rate of calibration.

This application discloses a 3.3V powered RS485 interface circuit, relating to the field of RS485 bus interface circuit driving, including: a high-level short-circuit protection unit for outputting a constant limiting current when short-circuited to ground; and a low-level short-circuit protection unit for outputting a constant limiting current when short-circuited to the power supply. The output port of the output stage unit is connected to the RS485 differential bus pin, and can withstand high or negative bus voltage while switching the output signal by turning it on and off according to the drive signal. A dynamic bias voltage node is formed inside the output stage unit, so that the substrate of the first PMOS transistor is always connected to a higher potential, avoiding the body diode from conducting. This application adopts a high-voltage PMOS single transistor and a high-voltage NMOS series diode structure, which simultaneously meets the bus voltage withstand of -7V to +12V and the RS485 protocol requirements at 3.3V; and can keep the short-circuit current constant at the threshold level when short-circuited to ground and short-circuited to the power supply, achieving constant current protection.

The application discloses a solar cell charging control method, equipment and storage medium, the method comprises the following steps: when the energy storage battery voltage and the solar cell voltage both meet the charging condition, the charging circuit module is controlled to start the solar cell to charge the energy storage battery, after starting charging, the charging circuit module input current is gradually increased, in the process, it is judged whether the input current reaches the constant current charging limit current, if it reaches, the charging enters the constant current charging stage; if it does not reach, it is judged whether the input voltage of the charging circuit module reaches the constant voltage charging limit voltage, if it reaches, the charging enters the constant voltage charging stage, if it does not reach, the input current continues to gradually increase until the charging enters the constant current charging stage, or the charging enters the constant voltage charging stage, when entering the constant current charging stage, the input current charges at the constant current charging limit current until the input voltage of the charging circuit module reaches the constant voltage charging limit voltage, at this time, the charging enters the constant voltage charging stage.

The present application relates to the technical field of power supply system core device health management, and discloses a method for 1 / f noise test by using a source table, comprising: performing short-time pre-detection in a thermal equilibrium stage to obtain a first-order drift rate of current; constructing a thermal drift linear prediction model to calculate a limit current envelope of a whole test period; locking an optimal static range with the highest resolution and meeting the upper limit of the range in a source measurement unit according to the limit current envelope; and continuously collecting time-domain fluctuation data under the fixed range and mapping the time-domain fluctuation data into a noise spectrum, wherein the present application effectively solves the contradiction between range overflow and insufficient quantization accuracy caused by thermal drift in long-period test through a prior range arbitration mechanism based on the drift envelope, eliminates transient interference introduced by dynamic range switching, and realizes nondestructive characterization of early defects of the device oxide layer.