68 results about "Dropout voltage" patented technology

This application belongs to the field of power electronics and automatic control technology, and relates to a power supply smooth switching control method for suppressing DC bus voltage surges. It solves the problem of DC bus voltage surges caused by potential changes during primary / standby power supply switching, including: dynamically matching the standby power supply output to the primary power supply voltage and reserving a voltage difference margin through voltage closed-loop feedback; initiating switching when a primary power supply fault is detected or the bus voltage drop rate exceeds a threshold; utilizing controlled current injection into the MOSFET gate to bring it into the Miller plateau region and allowing it to remain in the linear operating region for a preset transition period; controlling the MOSFET drain-source equivalent resistance to continuously decrease according to an S-shaped function to absorb transient energy; and locking the fully conducting state to complete seamless switching when the drain-source voltage difference approaches zero. This method effectively eliminates high-frequency oscillations, achieves microsecond-level potential transitions, significantly improves system reliability and response speed, and is suitable for high-reliability power supply scenarios with stringent "zero-inductive switching" requirements.

The application discloses a charging circuit and a vehicle, and relates to the technical field of vehicle power supply. The charging circuit is suitable for being electrically connected with an external charging pile. The charging circuit comprises at least two charging modules, and the at least two charging modules are configured to perform at least twice voltage transformation charging on a battery. In the case that the voltage difference of each charging module is certain, the voltage difference of the charging circuit can be larger after twice voltage transformation, so that the charging circuit can be adapted to a larger range of charging voltages, that is, the charging circuit can be adapted to more types of charging piles, and the compatibility of the charging circuit to different charging piles is improved. Alternatively, in the case that the voltage difference between the required voltage of the battery and the charging voltage provided by the charging pile is certain, the battery can be charged through twice voltage transformation, the voltage difference of each charging module can be reduced, and then the loss can be reduced, the heating problem can be alleviated, and the system safety and reliability can be improved.

This utility model discloses a piezoelectric ceramic air pump drive circuit, belonging to the technical field of piezoelectric ceramic air pump control. The circuit includes a main control processing unit, a program download unit, a low-dropout voltage regulator unit, an H-bridge piezoelectric ceramic air pump drive unit, and a DC-DC boost unit. The input terminals of the low-dropout voltage regulator unit and the DC-DC boost unit are connected to an external power supply, providing a stable low-voltage operating power supply to the main control processing unit and a high-voltage power supply to the H-bridge piezoelectric ceramic air pump drive unit. The H-bridge piezoelectric ceramic air pump drive unit uses complementary metal-oxide-semiconductor field-effect transistors to construct a full-bridge topology. The main control processing unit outputs complementary pulse width modulation signals to control the switching of the transistors in the H-bridge, generating a high-voltage alternating drive signal at the interface connecting to the air pump. This utility model features high integration, flexible control, and high drive efficiency, making it suitable for piezoelectric ceramic air pump applications requiring high-voltage, high-frequency drive.

This invention discloses a control method and device for suppressing single-phase circulating current in two parallel converters. The method employs a parallel current closed-loop controller and two individual converter current closed-loop controllers: the former outputs a parallel equivalent duty cycle to stabilize the total output current; the latter independently regulates each converter, outputting its own three-phase reference voltage. The three-phase voltage difference compensation is obtained by calculating the difference between the two sets of individual converter three-phase reference voltages phase by phase, and this compensation is superimposed on the parallel equivalent duty cycle. This dynamically adjusts the duty cycle distribution of each phase in the two converters, precisely offsetting the voltage difference caused by non-ideal device and parameter settings, effectively suppressing low-frequency single-phase circulating current. During duty cycle adjustment, this invention maintains the timing structure of the original modulation strategy to the greatest extent possible, achieving suppression of single-phase low-frequency circulating current while maintaining system output performance.

This invention relates to the field of LED lighting driver technology, and discloses a dual-voltage adaptive LED load topology adjustment circuit, comprising: an input rectification module, a load branch module, a topology control module, and a linear constant current adjustment module; the topology control module uses a voltage regulator detection branch to monitor the rectified voltage amplitude, generates a control level based on the internal semiconductor breakdown characteristics, and drives a transistor switching array to reconstruct the connection path between load branches; when the rectified voltage is in the first range, the parallel circuit is connected, and when the voltage reaches a threshold, it switches to the series circuit, and the linear constant current adjustment module regulates the current of the light-emitting device; this invention achieves spontaneous reconstruction of the load topology through hardware physical response, reduces redundant voltage drop and power loss in the driver circuit, and maintains the consistency of luminous brightness under different input voltages.

This invention discloses a power grid risk early warning method based on digital twins, belonging to the field of power grid risk early warning technology. The method includes: firstly, integrating data from the power grid energy management system, production management system, and information security system to construct a digital twin base for the primary system physical model, the secondary system mechanism model, and associated operating modes; then, considering the virtual automatic voltage control constraint calculation baseline situation; subsequently, injecting hypothetical equipment faults, and linking the execution of electromechanical transient analysis, relay protection action prediction, standby automatic transfer action prediction, and power flow recalculation to form a predictive topology; further, combining power source backtracking and dynamic voltage difference calculation at both ends after virtual disconnection of tie switches, identifying single-source risks, risks from the same upstream power source, and risks of double circuits on the same pole. This method achieves unified extrapolation of power grid operating status, secondary device actions, and structural risks, improving the completeness, foresight, and targeted level of risk identification and response.

This invention relates to the field of power management technology. This application discloses a low-dropout voltage regulator circuit based on low-voltage devices adapted to high-voltage power supplies. To solve the problems of existing solutions requiring high-voltage devices, high cost, and inability to reuse low-voltage designs, this invention uses only low-voltage process devices. Overvoltage protection is achieved through a common-gate transistor with fixed gate bias, clamping the high-voltage input to a safe range. The control signal voltage is limited through a voltage divider clamping network. During power down, a voltage divider design is used to simultaneously turn off the power supply and ground switches. A pull-up start-up circuit to prevent degeneracy is also integrated. This circuit can directly convert a high-voltage input into a stable low-voltage output, driving ordinary low-voltage circuits without any modification, realizing the direct reuse of low-voltage designs in high-voltage scenarios. This solution has the advantages of extremely low cost, high security, low power consumption, reliable startup, and full compatibility with standard low-voltage CMOS processes, greatly expanding the application boundaries of low-voltage processes.

This application discloses a pulse power amplifier modulation circuit, relating to the field of radar technology, which includes a pulse power amplifier modulation circuit applied in radar. The circuit comprises a PWM signal generation module, an isolation module, and a differential voltage regulation module connected in sequence. The differential voltage regulation module is also connected to a radar power amplifier module. The differential voltage regulation module includes a first adjustable resistor, a second adjustable resistor, and a push-pull circuit unit. One end of the first adjustable resistor is connected to the radar power supply, and the other end is connected to the isolation module. One end of the second adjustable resistor is connected to the isolation module, and the other end is grounded. The other end of the first adjustable resistor is also connected to the input terminal of the push-pull circuit unit, and the output terminal of the push-pull circuit unit is connected to the radar power amplifier module. This application improves the driving capability and level control accuracy of the PWM signal and effectively avoids the risk of PMOS burnout caused by excessive VGS voltage difference.

The present invention discloses a centralized control method for a variable flow multi-module variable frequency air source heat pump energy station, comprising the following steps: S1, grouping the air source units into groups, each group of air source units is equipped with an inlet electric valve, and the variable frequency water pump is connected to the air source unit through the inlet solenoid valve; S2, starting the variable frequency water pump with the shortest running time, selecting the air source unit group Am with the shortest running time among the non-running groups, opening the inlet electric valve Vm corresponding to Am, and starting the Am unit when the temperature difference between the return water temperature and the set temperature is greater than the load temperature difference; S3, triggering an additional unit start command when the temperature difference between the return water temperature and the set temperature is greater than the load temperature difference; triggering a unit reduction command when the temperature difference between the return water temperature and the set temperature is less than the load reduction temperature difference; S4, calculating the operating frequency of the variable frequency water pump through PID according to the system set pressure difference and the pressure difference between the distributor and the collector, adjusting the opening of the bypass regulating valve to improve the overall efficiency of the energy station.

The utility model discloses a kind of broken line detection circuit and low pressure acquisition terminal for low pressure acquisition terminal belongs to broken line detection field.The circuit includes MCU chip, differential pressure detection circuit, signal conversion circuit and signal driving circuit, the input end of differential pressure detection circuit is connected respectively the high potential interface and low potential interface of to-be-detected circuit, output end connects signal conversion circuit input end, signal conversion circuit output end connects signal driving circuit input end, finally by signal driving circuit, detection result is reported to MCU chip, detection process does not need MCU chip to participate.The circuit uses ordinary visible electronic device, and production cost is low.It can be directly embedded into the board level inside of low pressure acquisition terminal, without additional installation on site, reduce the unexpected failure caused by on-site installation, and the running stability is high.

This invention discloses a method and apparatus for detecting grounding faults in substation battery banks based on square wave injection, belonging to the field of DC power system fault diagnosis technology. The method includes: real-time measurement and calculation of the total voltage across the series-connected battery bank; when the insulation resistance to ground of the positive and negative busbars is lower than a preset insulation threshold, a low-frequency square wave voltage signal is simultaneously injected into the positive and negative terminals of the DC busbars via an injection resistor network; the response voltage across the measuring resistor is simultaneously acquired; based on the voltage difference of the response voltage, the difference between the positive and negative half-waves of the injected square wave voltage, and the known resistance value, the grounding resistance and the relative location of the grounding fault are calculated; and the specific battery number where the grounding fault occurred is determined according to the total number of battery cells in the battery bank and the calculated relative location of the grounding fault. This invention achieves accurate measurement of battery grounding resistance and automatic location of faulty batteries through square wave injection, significantly improving the operational reliability of the DC system.

The application discloses a parallel circulating current suppression method and device of a fractional order inverter, electronic equipment and a storage medium, and comprises the following steps: establishing a mathematical model of a fractional order inverter comprising a fractional order inductor and a fractional order capacitor, constructing a voltage and current double control loop based on a fractional order controller based on the mathematical model, and tracking and controlling the output voltage and current of the parallel fractional order inverters, and suppressing the circulating current by power sharing of the parallel fractional order inverters through droop control and fractional order virtual impedance. On the one hand, the voltage and current double control loop based on the fractional order controller can track the output voltage of the inverter, improve the tracking effect of the output voltage, reduce the voltage difference between the inverters, and suppress the parallel circulating current. On the other hand, the droop control combined with the fractional order virtual impedance can improve the power distribution response speed of the fractional order inverter, improve the power distribution accuracy between the inverters, and improve the suppression effect of the parallel circulating current.

The invention relates to a method for operating a power converter (10) for exchanging electrical power (PDC,PAC) between a DC unit (11) and an AC grid (13). The DC unit (11) is connected to a DC connection (12) of the power converter (10) and exchanges a DC power (PDC) with the power converter (10) on the basis of a DC voltage (UDC) at the DC connection (12), and the AC grid (13) is connected to an AC connection (14) of the power converter (10) and exchanges an AC power (PAC) with the power converter (10) via the AC connection (14) on the basis of a voltage curve deviation between an AC voltage curve (UAC) generated by a clocked bridge circuit (15) of the power converter (10) and a grid voltage curve (Ugrid). The power converter (10) adjusts the AC voltage curve (UAC) on the basis of an AC power control value (PAC,set) by means of a grid-forming AC controller (20) and varies the AC power (PAC) by means of an adjustable induced power response for network events. The induced power response comprises a dynamic AC power deviation between the AC power (PAC) and a power setpoint value. The method is characterized in that the induced power response to a network event is adjusted using an asymmetry characteristic curve (50, 51, 52, 53). The asymmetry characteristic curve (50, 51, 52, 53) specifies different increases of a parameter (p) of the AC controller (20) and / or a DC controller (30) as a function of the sign of a deviation (p-plim) of the parameter (p) from a parameter limit value (plim), wherein the parameter (p) comprises in particular a DC voltage difference (ΔUDC) between the DC voltage (UDC) and a DC setpoint voltage (UDC,set) and / or an AC power difference (ΔPAC) between the AC power (PAC) and the AC power control value (PAC,set). The invention further relates to a power converter and to an energy supply

The application discloses a self-leveling air gap equalization and multi-cavity stable voltage ultra-low disturbance air cavity system and a control method, and belongs to the field of aircraft control and ground simulation. The system comprises an outer shaft air floating sleeve, an inner shaft movement sleeve, a lifting device, a surrounding air gap monitoring device, a distributed air pressure sensor array and an air path control board card; an automatic air gap pressure difference elimination is realized by adopting a surrounding communication air path, and a partitioned air supply and a feedforward pressure field shaping are matched, and a constant air cavity volume is maintained by the synchronous lifting device to weaken the hysteresis effect. The control method relies on a neural network offline training to build a compensation model, and realizes closed loop stable voltage and disturbance suppression by adopting a feedforward neural backstepping control. The application can effectively improve the precision, stability and dynamic response of vertical microgravity simulation, and solves the multi-source disturbance problem caused by air gap loss, air supply and exhaust coupling and hysteresis feedback of a traditional pneumatic compensation system.

This utility model relates to a power supply regulation circuit and electronic device. The circuit includes: a signal acquisition module for acquiring electrical signals from a load; a power control module including a power supply unit, a power adjustment transistor, and an operational amplifier unit, wherein a first signal terminal of the power adjustment transistor is connected to the power supply unit, and a second signal terminal is connected to the load; the operational amplifier unit is connected to the controlled terminal of the power adjustment transistor and is used to compare the electrical signals acquired by the signal acquisition module with a reference signal, and output a drive signal to control the power adjustment transistor to operate in the linear region, so that the output signal of the power adjustment transistor is maintained at a target value determined by the reference signal; a protection module including: a differential voltage detection unit connected to the power adjustment transistor for detecting the voltage difference between the first and second signal terminals of the power adjustment transistor; and a power supply regulation unit for adjusting the output voltage of the power supply unit based on the voltage difference output by the differential voltage detection unit. Using this power supply regulation circuit reduces the risk of device damage.

The utility model belongs to power distribution technical field, concretely relates to a power device and wireless charging system based on power threshold dynamic control, and this power device includes: control module, load voltage detection unit, power factor correction unit and feedback voltage regulation unit, control module is still configured as control power factor correction unit starts or closes, and feedback voltage regulation unit is configured as with power factor correction unit synchronous action, to the total circuit output corresponding reference voltage signal, the utility model closes power factor correction unit in low power, reduces inherent loss in power factor correction unit, simultaneously, feedback voltage regulation unit output low reference voltage can reduce the front stage drive pressure difference, and activates power factor correction unit in high power, promotes the power factor of input voltage, and feedback voltage regulation unit output high reference voltage satisfies high power drive demand.

The present application relates to the technical field of negative pressure sputum suction device, disclose a kind of based on automatic identification voltage's negative pressure sputum suction device, utilize sputum viscosity estimation module by to pipeline upstream and downstream pressure difference data and flow data are combined operation, obtain sputum viscosity estimation value, controller is accordingly dynamically generated and contains negative pressure climb, peak platform superimposed high-frequency micro-pulse disturbance and slowly release three section structure's bionic attraction waveform.Multiple-point pressure difference positioning module is positioned to the blockage position by the pressure difference sensor array arranged along pipeline, and hierarchical dredging module is targeted negative pressure pulse intervention according to blockage position and blockage component type.Utilize the circuit board in the controller inside detection input voltage, judge input voltage is 110V or 220V, then automatically switch to corresponding line, carry out double voltage self-adaption.

The application provides an MPPT circuit control method, an MPPT circuit and an energy storage device. The method comprises the following steps: detecting a first voltage and a first current input by a first branch and a second voltage and a second current input by a second branch in real time; determining a working state of the MPPT circuit according to the first voltage and the second voltage; and adjusting the power of a target branch through a first voltage boosting circuit or a second voltage boosting circuit according to the power difference between the first branch and the second branch when the MPPT circuit is in a pressure difference state. In the embodiment of the application, when the MPPT circuit is in the pressure difference state, the power of the target branch with lower power is dynamically adjusted, so that the power of the target branch is the same as the power of another branch except the target branch in the MPPT circuit, thereby ensuring that each branch works with the maximum power supported by the MPPT circuit, and further maximizing the use of light energy and improving the working efficiency of the MPPT circuit.

This invention belongs to the field of electrical component technology, specifically relating to a control circuit for rapid gain adjustment of a photomultiplier tube, a photomultiplier device, and a wafer defect detection system. The control circuit for rapid gain adjustment of a photomultiplier tube includes: a photomultiplier tube, a first constant current circuit, a second constant current circuit, and a driving unit. The driving unit is configured to output a changing voltage to the first and second constant current circuits, causing a change in the voltage of each multiplier electrode in the first and second multiplier electrode groups. This invention can output a high-speed changing voltage with a period as low as 10ns, causing the voltage of the corresponding multiplier electrode in the first and second constant current circuits to change rapidly, i.e., a voltage difference change occurs between adjacent multiplier electrodes in the first and second multiplier electrode groups, thereby changing the amplification factor and achieving a rapid gain change at the 10ns level.

The application discloses a driving stage circuit, a linear voltage stabilizer and a power supply device, comprising: an NMOS source follower connected between an error amplifier and a control end of a power tube, used for outputting a first driving current to the power tube when turned on; a PMOS source follower connected between the error amplifier and the control end of the power tube, used for outputting a second driving current to the power tube when turned on; and a switching circuit used for comparing a voltage difference between the control end voltage of the power tube and a reference ground with a set threshold value, and complementarily turning on the PMOS source follower and the NMOS source follower according to a comparison result, no matter a load state of the LDO, the driving stage circuit can always select an optimal driving type to drive the power tube, thereby improving a problem that loop stability of a driving stage circuit in the prior art is easily limited by a working voltage range.

The application discloses a low-voltage distribution network closing loop monitoring system based on IoT, and belongs to the technical field of distribution network monitoring. In the application, by monitoring key electrical parameters such as pressure difference and phase angle difference in real time, the system can ensure that the state of the power grid of two stations before closing loop operation is compatible, thereby avoiding closing loop failure or power grid accidents caused by electrical parameter mismatch. By automatically calculating closing loop impact current, steady-state current, phase angle difference and distribution transformer load rate difference, the system can provide scientific judgment basis for the operator, so that the closing loop operation is more accurate and reliable. The operator can understand the state of the power grid in real time through the remote online monitoring system, improve the work efficiency, and reduce the personnel safety risk. With digital support, the system can quickly respond to power grid changes, timely adjust the closing loop operation, and improve the operation efficiency and power supply reliability of the power grid. Real-time monitoring and rapid judgment reduce the power outage time caused by closing loop operation, and improve the power experience of users.

This invention provides a passive infrared detection device that can shorten power-on time. The passive infrared detection device includes a pyroelectric infrared sensor and an amplifier circuit. The amplifier circuit uses a non-inverting negative feedback amplifier circuit powered by dual power supplies as the primary amplifier circuit. A step-down voltage divider circuit is configured to pull down the DC bias voltage of the detection signal output from the signal output terminal of the pyroelectric infrared sensor. In this way, at the beginning of power-on of the passive infrared detection device, there is a small voltage difference between the non-inverting and inverting input terminals of the operational amplifier of the primary amplifier circuit. This reduces the time required for the voltage between the non-inverting and inverting input terminals of the operational amplifier to become consistent during the charging and discharging process, thereby shortening the power-on time of the primary amplifier circuit.

This invention provides a rail-to-rail output control and guidance circuit, comprising a constant current generation module and a control and guidance module. The constant current generation module generates an adjustable constant drive current; the control and guidance module receives a PWM control signal and generates a PWM control guidance signal based on the PWM control signal and the constant drive current. By using the constant current generation module and the control and guidance module, this invention eliminates the voltage difference between the output voltage and the input voltage. Simultaneously, the controllable output current effectively avoids excessive power consumption or heat generation, thus improving the working efficiency of the control and guidance circuit.

This application discloses a floating power domain circuit. The circuit includes: an impulse-resistant output unit, a first voltage correlation unit, a second voltage correlation unit, and a bias power supply unit. The impulse-resistant output unit includes a common-gate amplifier structure for receiving an external high-voltage input and outputting a floating power supply terminal, suppressing the impact of external high-voltage input jumps on the floating power supply terminal through the common-gate amplifier structure. The first voltage correlation unit is electrically connected between the floating power supply terminal and an external reference voltage, establishing a voltage correspondence between the floating power supply terminal and the external reference voltage. The second voltage correlation unit is electrically connected between the floating power supply terminal and a floating ground terminal, establishing a voltage correspondence between the floating power supply terminal and the floating ground terminal, such that the voltage difference between them is formed by the superposition of the threshold voltages or gate-source voltages of at least two active devices. The bias power supply unit provides a stable bias current to each unit.

This invention discloses an intelligent terminal for phase-switching switches based on three-phase self-balancing and low-voltage fault location and isolation, belonging to the field of intelligent control technology for phase-switching switches. Through research on residual current change curves and characteristic components, distribution characteristics, and three-phase self-balancing techniques before and after a low-voltage distribution area fault, this invention proposes a residual current protection strategy using the transient component of the residual current as the logic action condition to achieve fault location and isolation in low-voltage distribution areas of the distribution network. It automatically acquires line impedance to deduce three-phase imbalance in the distribution area and combines it with phase-to-phase voltage difference to achieve three-phase self-balancing. Furthermore, through research on low-power wireless technology, it enables the uploading of measurement and fault information, providing data support for the analysis and processing of low-voltage faults and improving the automation level of the distribution network.

This invention provides a high-precision compensation circuit, method, and device for multiple input voltage channels. It detects the input signal to the MCU processor using at least one first detection circuit, and performs voltage detection and compensation on multiple first detection circuits using a second detection circuit. Based on the voltage difference, it performs differential voltage compensation, achieving consistent control of multiple input voltage channels. Through simple calculations, it eliminates errors caused by temperature variations in diode forward voltage and leakage current of clamping diodes, improving detection accuracy. The compensation circuit, combining the first and second detection circuits, achieves an error of less than 0.05V within an input voltage range of 0~36V.

The application relates to the field of circuit design, in particular to a clamping circuit of a power device and a VI source board. The clamping circuit comprises a positive clamping circuit and / or a negative clamping circuit; the positive clamping circuit comprises a first differential amplifier circuit, a positive compensation network and a first biasing circuit; the positive compensation network is connected between the inverting input end and the output end of the first differential amplifier circuit; the first differential amplifier circuit is configured to output the comparison result of a measured output value and a positive clamping set value to the first biasing circuit; the negative clamping circuit comprises a second differential amplifier circuit, a negative compensation network and a second biasing circuit; the negative compensation network is connected between the inverting input end and the output end of the second differential amplifier circuit; and the second differential amplifier circuit is configured to output the comparison result of a measured output value and a negative clamping set value to the second biasing circuit. The clamping circuit arranged outside the power device improves stability and clamping precision.