6291 results about "Voltage reference" patented technology

The invention relates to the technical field of integrated circuit test and calibration, and discloses a chip test and calibration method and a chip tester. The chip test calibration method is applied to a chip test module and specifically comprises the following steps that S101, a starting signal sent by a user terminal is received, environment initialization operation is executed, and after initialization is completed, a system automatically enters a standby mode and waits for an external trigger signal or a user instruction; and S102, synchronously capturing input and output signal waveforms of the tested chip at a preset sampling frequency through a high-precision current sensor and a voltage sampling circuit. Through a dynamic parameter acquisition and real-time compensation technology, a voltage reference error is effectively reduced, the temperature control precision is superior to + / -0.3 DEG C, signal distortion caused by environmental interference is effectively inhibited, a multi-dimensional calibration model is combined with time domain, frequency domain and statistical characteristic analysis, nonlinear errors and system drift can be dynamically corrected, and the system performance is improved. And the attenuation error of a test signal transmission path is lower than 0.02 dB.

An interface circuit includes a reference voltage generation circuit to generate a reference voltage, a differential voltage signal generation circuit to convert send data input in sending data into a pair of differential voltage signals and output the pair of differential voltage signals based on the reference voltage generated by the reference voltage generation circuit, a receiver to convert a pair of differential voltage signals input in receiving data and output received data, and a receiver test circuit to perform a sensitivity test of the receiver, the receiver test circuit having a resistance circuit to generate a pair of differential voltage signals having a potential difference being necessary for the sensitivity test of the receiver.

The invention provides a server voltage monitoring system and method, electronic equipment and a storage medium, and relates to the technical field of computers, the system comprises a complex programmable logic device CPLD, and an initial timing module, a voltage acquisition module, an abnormal data storage module, a CPU processor and a baseboard management controller BMC module which are respectively in communication connection with the CPLD. The initial timing module activates the monitoring function of the CPLD through a startup signal; the voltage acquisition module acquires voltage data under the control of the CPLD so as to read the voltage data of the server mainboard; the CPLD obtains voltage data, compares the voltage data with a reference voltage range of the abnormal data storage module, triggers an interrupt signal after identifying abnormal fluctuation voltage, and feeds back the interrupt signal to the CPU and the BMC, so that the CPU and the BMC quickly output an alarm. The system covers full-cycle monitoring from startup to BMC startup, supports efficient acquisition, dynamic detection and low-delay response of multi-path voltage, relieves the voltage pressure of a BMC monitoring mainboard, and provides reliable guarantee for power supply safety of a server.

The invention provides a frequency converter dynamic fault diagnosis method and system based on a multi-brand load test platform. According to the method, multiple real-time operation parameter sets are acquired, the amplitude attenuation threshold and the frequency fluctuation interval of a voltage waveform fragment are dynamically adjusted according to a load mode configuration file, the dynamic voltage reference parameter corresponding to the current load mode is generated, and then the actual waveform and an expected current phase curve are compared frame by frame; the method comprises the following steps: firstly, calculating to obtain a phase offset, then constructing a multi-dimensional operation characteristic spectrum, then carrying out time sequence cross validation on a sudden change time node of a power factor jump trajectory and an abnormal waveform position in a harmonic distortion incidence matrix, outputting an abnormal mode code, and finally, matching a load adaptation grade constraint condition to generate a diagnosis report; according to the technical scheme provided by the invention, the fault diagnosis precision and the cross-brand system adaptation capability in a complex load scene are remarkably improved, and the problem of misjudgment of a single brand threshold rule in a multi-device scene is effectively solved.

The present invention discloses a method for diagnosing micro-short circuit fault of a battery, comprising: acquiring real-time voltage data of each battery in battery module of electric vehicle, obtaining voltage matrix after noise elimination; calculating dynamic reference voltage sequence of the each battery in the voltage matrix within sliding window length, extracting eigenvalues of the each battery at different times; calculating correlation coefficients between voltages of the each battery at different times and reference voltage within the sliding window; forming feature point matrix of the battery module based on the eigenvalues and the correlation coefficients; calculating dynamic reference feature point sequence based on the feature point matrix, and calculating improved Frechet distances between feature point sequences of the each battery and the dynamic reference feature point sequence, using Frechet distance values as anomaly scores of the each battery; thus, judging whether a short-circuit fault occurs in the each battery.

The invention relates to the technical field of resonance suppression, and discloses an active damping control LC resonance suppression method and device. The method comprises the following steps: performing parameter identification processing based on bus voltage to obtain an inductance value, a capacitance value and a resonance frequency of an LC circuit; extracting a resonant current component of the current signal based on the resonant frequency; calculating damping power according to the resonance current component, and converting the damping power into a voltage compensation instruction under an alpha-beta coordinate system; generating a PWM control signal according to the voltage compensation instruction and a voltage reference instruction; and performing on-off control on the inverter based on the PWM control signal, and injecting power opposite to the resonant current component into the LC circuit to generate a virtual damping effect. Virtual impedance characteristics are seamlessly integrated into inverter control, rapid response of the whole process from resonance detection to power injection is ensured, the resonance peak value is effectively suppressed, and the current quality is improved.

The invention provides a COT step-down converter comprising an inductive current detection circuit configured to detect an inductive current flowing through an inductor connected to a system output of an output voltage of an output system of the COT step-down converter, and generate a current zero-crossing detection signal indicating whether the inductive current crosses zero, the inductive current zero-crossing means that the inductive current is changed from positive current to negative current; and a sleep mode control circuit configured to generate a sleep mode control signal for controlling one or more circuit modules in the COT buck converter to change from an operating state to a closed state based on the current zero-crossing detection signal, an output feedback voltage representing a system output voltage of the COT buck converter, and a predetermined reference voltage.

The invention relates to the technical field of parallel connection of energy storage inverters, in particular to a synchronous control method of an energy storage inverter system supporting multi-machine parallel connection, which comprises the following steps of: according to a preset rule, assigning one inverter as a master node and the other inverters as slave nodes; when it is detected that the running state of the main node exceeds a preset abnormal threshold value, a main control switching process is triggered; dynamically electing a new host strategy based on a preset priority, and dynamically electing an inverter as a new host node; the other inverters synchronously switch the tracking target and update the synchronization reference; in the switching process, the new main node smoothly establishes a voltage reference by adopting a phase pre-synchronization and slope transition strategy. According to the invention, by introducing a dynamic master node switching mechanism, when the master node is abnormal, the master control responsibility is automatically, quickly and smoothly transferred to the healthy slave node, the AC side voltage frequency synchronization and the DC side bus voltage stability are maintained, and the continuous and stable operation of the multi-machine parallel system under the condition of the master node fault is ensured.

The invention relates to the technical field of semiconductor laser power supplies, in particular to a semiconductor laser power supply control circuit based on linear constant current and a method thereof. According to the technical scheme, the circuit comprises a voltage follower module, a linear constant-current driving module, a power switch module, a pulse control module, a sampling feedback module and a follow current protection unit. The in-phase input end of an operational amplifier OPA320 of the voltage follower module is connected with external reference voltage # imgabs0 #, the inverted input end of the operational amplifier OPA320 is grounded through a first resistor R1 and connected with the output end through a second resistor R2, and a filter capacitor C1 is connected to the two ends of the second resistor R2 in parallel. Through a linear constant current control and pulse cooperation mechanism, the current stability and the dynamic response speed of the semiconductor laser under the wide-range and high-frequency working condition are remarkably improved, and it is guaranteed that the laser output power is accurate and reliable.

A control circuit for a switching power supply with adaptive voltage positioning control, can include: a compensation signal generation circuit configured to receive a digital voltage reference signal, a digital voltage sampling signal representing an output voltage of the switching power supply, and a digital droop voltage, and to integrate an error between the digital voltage reference signal and a sum of the digital voltage sampling signal and the digital droop voltage, in order to generate a compensation signal; and an adaptive voltage positioning control circuit configured to generate a positioning signal according to the compensation signal, in order to adjust the output voltage.

Proposed is a device for receiving a four-level pulse amplitude modulation (PAM-4) signal, which includes a first comparator for comparing a received PAM-4 signal with a predetermined threshold voltage to output a most significant bit (MSB) signal; and a second comparator for comparing the differential signal difference between the positive signal and negative signal of the received PAM-4 signal with a reference voltage to output a least significant bit (LSB) signal.

The invention provides a display device and a driving chip of a display panel. The display device comprises the display panel and the driving chip. The driving chip comprises a first comparator and a second comparator; the driving chip is used for dividing the output channels corresponding to the at least two data lines into a first channel with positive polarity and a second channel with negative polarity; a first comparator for comparing the first voltage with a first reference voltage to output a first level; the second comparator is used for comparing the second voltage with a second reference voltage and outputting a second level; and the driving chip is also used for continuously monitoring the first level and the second level so as to detect whether a short circuit between the data lines occurs in the display panel or not. The data line is divided into the positive and negative polarity channels through the driving chip, the comparator is used for comparing the channel voltage with the reference voltage, the level change is monitored to detect the short circuit, an amplifier and a complex switch assembly do not need to be additionally arranged, the circuit structure is simplified, and the manufacturing cost is reduced.

The invention discloses a multi-objective optimization method and system for dual active bridge circuit expansion phase shift modulation, and the method comprises the steps: calculating a voltage matching ratio, and determining an external phase shift angle ratio based on a difference value between an output voltage and an output voltage reference value; according to the voltage matching ratio and the external phase shift angle ratio, obtaining an internal phase shift angle ratio of the primary side full bridge through an offline lookup table; calculating the maximum transmission power of the dual-active bridge converter, and determining a current working mode from the six preset working modes based on the size relationship between the inner phase shift angle ratio and the outer phase shift angle ratio; generating an optimal modulation strategy through a multi-objective optimization algorithm by taking the current effective value and the current peak value as optimization objectives and combining the voltage matching ratio and the periodic parameters of the current working mode; and generating a trigger signal of each switch tube of the dual-active bridge converter. Through six-mode working area division, complete differential algorithm boundary constraint and off-line-on-line collaborative optimization, the contradiction between the current stress and the soft switching range of the converter under extended phase shift modulation is solved.

The invention relates to the technical field of electric energy conversion control, and discloses a multi-source load auxiliary power supply power balance control system, which comprises a sampling module, a control module and a modulation module, the sampling module obtains parallel converter branch current and direct current bus voltage; the control module determines a weight by utilizing physical associated association of a bus voltage change gradient and branch current change polarity, corrects a dynamic slope factor determined by a current change rate according to the weight, and performs upper limit clamping on the dynamic slope factor according to a bus voltage margin; according to the invention, the rigid restriction of droop control logic is eliminated, the power deviation generated by asymmetry of feeder impedance is automatically offset while the bus voltage stabilization precision is maintained, and the convergence speed and the certainty of the system during violent load switching are improved.

The invention discloses a slew rate enhancement circuit of an operational amplifier, which comprises a comparison module used for comparing a positive input voltage and a negative input voltage of the operational amplifier and generating a first comparison signal and a second comparison signal according to a comparison result; the slew rate enhancing module is used for enhancing the slew rate of the falling edge of the output voltage of the operational amplifier according to the first comparison signal and enhancing the slew rate of the rising edge of the output voltage of the operational amplifier according to the second comparison signal; the common-mode feedback module is used for clamping the common-mode voltage of the first comparison signal and the common-mode voltage of the second comparison signal to a reference voltage when the operational amplifier is in a steady state, so that the slew rate enhancing module is in a closed state; therefore, the slew rate of the output voltage of the operational amplifier can be quickly enhanced when the operational amplifier has large step signal output, so that the output of the operational amplifier is quickly responded and established.

The invention discloses a flash memory data decoding method and device, electronic equipment and a readable storage medium, and relates to the technical field of data decoding, and the method comprises the following steps: obtaining a current data reading result of a storage unit through a current left offset reference voltage, a non-offset reference voltage and a right offset reference voltage in current reading voltages; if decoding of the current data reading result fails, the current left offset reference voltage is immediately and dynamically adjusted based on a preset offset, so that the adjusted first left offset reference voltage is smaller than the current right offset reference voltage to generate a first reading voltage; therefore, when the characteristic changes such as threshold voltage drift occur in the long-term use of the flash memory storage unit, the fixed reference voltage is not continuously used, the read voltage is flexibly adjusted, the decoding failure caused by insufficient voltage adaptation is avoided, and the decoding success probability is improved.

The present application relates to the technical field of wind power generation, and discloses a control method and apparatus for a grid-forming doubly-fed wind turbine generator, a generator, and a medium. In embodiments of the present application, a current reference value of a grid connection point is determined on the basis of measurement parameters of the grid connection point in combination with an internal potential parameter of a grid-forming doubly-fed wind turbine generator and a virtual impedance reference value, a voltage reference value of a grid-side converter is further determined on the basis of the current reference value of the grid connection point, and the grid-side converter is modulated on the basis of the voltage reference value, thereby implementing closed-loop control of the grid-side converter, such that a difference between an output voltage value and the voltage reference value of the grid-side converter is less than a preset threshold.

The invention provides a driving method of a display panel, a driving circuit and a display device.In the driving method of the display panel, reference voltage and environment temperature form a first mapping table, target electrical parameters of the display panel and the environment temperature form a second mapping table, and a temperature sensing module is adopted to detect the environment temperature of the display panel; the method comprises the following steps: acquiring a corresponding detection voltage, comparing the detection voltage with a changing reference voltage, acquiring a target reference voltage according to an overturning state of a level signal obtained by comparison, and acquiring a current environment temperature according to the target reference voltage; various target electrical parameters of the display panel are determined according to the environment temperature and the second mapping table, parameter adjustment of the display panel is carried out, linkage adjustment of the multiple different electrical parameters is achieved, it is guaranteed that the display panel obtains different voltage setting and driving voltages at the current environment temperature, the effectiveness of low-temperature compensation is improved, and the user experience is improved. The deflection consistency of the liquid crystal is realized, and the display effect is improved.

The invention provides a fault ride-through control method for a network construction type converter, and belongs to the technical field of energy storage converters and the like. The method comprises the following steps: firstly, measuring PCC voltage and power grid side current, calculating amplitudes of the PCC voltage and the power grid side current, and then judging whether the PCC voltage drops below a set threshold value or not; if not, keeping the active power reference and the voltage amplitude reference unchanged; and if so, performing active power reference modification: judging whether a current limiting strategy is triggered, if not, locking the PCC voltage reference as a measured value, and if so, gradually decreasing the PCC voltage reference by an increment value based on the measured value. According to the invention, accurate evaluation of the existence of the stable equilibrium point is realized; meanwhile, an improved fault ride-through control method is provided, active power reference and voltage amplitude reference are dynamically modified, so that the grid-forming converter is transited to a new stable balance point during a fault period, and current limiting, transient synchronization stability improvement, PCC voltage source characteristic maintenance and maximum fault current output can be taken into account.

The present invention provides a method for cooperatively suppressing a common-mode voltage and current harmonics of coupled three-level inverters, comprising: based on amplitude and phase angle of reference voltage vector, determining sector and region in which the reference voltage vector is located; selecting four basic voltage vectors with low common-mode voltage amplitudes to synthesize the reference voltage vector; writing volt-second balance equation based on selected basic voltage vectors, and calculating duty cycles thereof; and based on sector and region in which reference voltage vector is located, set value of voltage difference across capacitors on direct current side, and actual value of voltage difference across capacitors on direct current side, (1) updating duty cycles of basic voltage vectors, to realize separate control of capacitor voltage; and (2) designing and converting switching sequence into PWM drive signal of power switch, to control the coupled three-level inverter to operate.

The invention discloses a hybrid effective flux linkage observer and a permanent magnet synchronous motor control method, device and system. The method comprises the following steps: carrying out Clarke conversion on an obtained three-phase current of the permanent magnet synchronous motor to obtain a current in a static coordinate system, and carrying out park conversion based on rotor position information to obtain a current in a synchronous rotating coordinate system; the effective flux linkage of the permanent magnet synchronous motor is obtained through the hybrid effective flux linkage observer; on the basis of the obtained effective flux linkage of the permanent magnet synchronous motor, dead-zone compensation voltage is obtained through self-adaptive gain dead-zone compensation calculation based on back electromotive force reconstruction, and the rotating speed and the rotor position of the permanent magnet synchronous motor are obtained through phase-locked loop calculation; according to the rotating speed and the rotor position of the permanent magnet synchronous motor, the current under the synchronous rotating coordinate system, the dead zone compensation voltage and the obtained reference rotating speed and reference current, the reference voltage of the motor at the k moment is obtained through a rotating speed loop and a current loop and used for achieving low-speed position-sensorless control over the permanent magnet synchronous motor.

The invention discloses a buck-boost circuit-based mppt charging current backflow prevention control method, and relates to the technical field of switching power supplies, and the method comprises the steps: collecting a photovoltaic input voltage, a battery output voltage, and an inductive current flowing through an inductor; the current input power is calculated based on the photovoltaic input voltage and the inductive current, and the reference voltage is dynamically adjusted through an MPPT loop algorithm; pI voltage loop operation is carried out on the output voltage and the adjusted reference voltage, and expected charging current is generated; pI current loop operation is carried out on the expected charging current and the inductive current sampling value after proportionality coefficient adjustment, and a PWM duty ratio control signal is output to adjust the driving states of the four switching tubes; when the judgment circuit is in an intermittent conduction mode and meets critical conditions, a driving signal of the fourth switching tube is shielded, and only a body diode realizes a current path to prevent reverse flow of current; the battery current is effectively prevented from flowing backwards, and the system safety and the energy utilization efficiency are improved.

A circuit is provided. The circuit can include sensing circuits configured to sense differences between first and second currents on selected bit lines of an array of memory cells and produce outputs for the bit lines as a function of the difference, and a global programmable non-regular counter configured to continuously provide a count value to each of the sensing circuits in dependence on a clock signal, wherein each sensing circuit, of the sensing circuits, includes (i) a local detector circuit configured to detect a voltage (Vc) generated according to the difference and (ii) a reference voltage selector configured to receive reference voltages from a source and to select a single reference voltage (Vref), and wherein each sensing circuit produces an output according to (i) a difference between Vc and Vref and (ii) a stored count value received from the counter.

The invention relates to the field of power grid simulation, and particularly discloses a control method of an alternating-current power grid broadband oscillation simulation device based on a component physical model, which realizes broadband domain oscillation simulation of an alternating-current power grid based on the component physical model and a notch filter. Specifically, according to the control method of the alternating-current power grid broadband oscillation simulation device based on the element physical model, an adjustable element physical model type and a corresponding impedance parameter serve as input conditions, and a dynamic voltage compensation component excited by power grid impedance is calculated in combination with an adjustable notch filter; and a power grid simulation reference signal is constructed in real time through superposition of an original input reference voltage value and a dynamic voltage compensation component excited by power grid impedance, so that oscillation simulation in a wide frequency domain of the alternating-current power grid is realized.

Disclosed are a memory device and a control method thereof. The memory device may be a high-capacity and high-performance three-dimensional NAND flash memory. The control method includes the following steps. Data for performing a programming operation on a specific memory cell area is obtained. A number of memory cells in a predetermined potential state in the data are counted as a first number value. The programming operation is performed on the specific memory cell area based on the data. A read operation is performed based on a reference voltage corresponding to the predetermined potential state. A number of memory cells in the predetermined potential state in the specific memory cell area after the programming operation are counted as a second number value. Whether the specific memory cell area has program disturbances is determined based on the first number value and the second number value.

The invention provides a method and system for optimizing reading reference voltage of a three-dimensional NAND flash memory, and relates to the technical field of semiconductor memorizes.The method comprises the steps that the erasing frequency and the data retention time of the three-dimensional NAND flash memory are obtained; if the data retention time is not clear, inversely deducing the time through a sampling adjustment method, inputting the inversely deduced data retention time and erasing times into an optimal read reference voltage prediction model, and outputting an average optimal offset value of each read reference voltage; if so, substituting the two parameters into an optimal read reference voltage prediction model to output an average optimal offset value of each read reference voltage; and finally, compensating the average optimal offset value of each read reference voltage by using the interlayer difference table, and outputting all optimal read reference voltages of each layer. According to the method and the device, the accuracy of reading reference voltage optimization strategy prediction can be improved, the time overhead is reduced, and the reading performance is improved.

The invention discloses a voltage acquisition circuit, an alternating current power supply, a voltage acquisition method, a voltage acquisition device and a medium. A far-end sampling unit; the in-phase input end of the first comparison unit is connected with the near-end sampling unit, and the inverted input end is grounded; the in-phase input end of the second comparison unit is connected with the far-end sampling unit, and the inverted input end is grounded; the input end of the XOR unit is connected with the output ends of the first comparison unit and the second comparison unit; the in-phase input end of the third comparison unit is connected with the output end of the XOR unit, the inverted input end inputs reference voltage, and the reference voltage is smaller than half of the power supply voltage; the control unit is used for judging that far-end sensing sampling is abnormal when the difference effective value of the voltages output by the near-end sampling unit and the far-end sampling unit is smaller than the preset compensation voltage and the abnormal comparison voltage output by the third comparison unit is 1. According to the invention, when the AC power supply outputs low voltage, the conditions of disconnection and reverse connection of the far-end induction sampling can be identified.

The invention discloses a voltage transformer metering error evaluation method, which relates to the technical field of voltage transformer metering and comprises the following steps of: constructing a synchronous acquisition system of multiple groups of voltage transformers in a transformer substation, acquiring original voltage data, constructing a virtual reference voltage generation model and outputting a reference voltage sequence; the method comprises the steps of establishing a virtual reference voltage model, calculating error statistical characteristics, marking the operating state grade of the voltage transformer, evaluating health scores according to the error characteristics, outputting a scoring result, receiving inspection feedback comparison differences, updating the model, generating an analysis chart, and uploading the analysis chart to a client display and linkage operation and maintenance system. On-line error evaluation is realized, multi-source data are fused, error features are dynamically extracted, an operation state is marked, a health scoring and early warning mechanism is established, a feedback closed loop is introduced to optimize model precision, an evaluation result is displayed in a chart form, operation and maintenance scheduling is assisted, and the real-time performance, the accuracy and the self-adaptive capability of evaluation are improved.

An amplification circuit is configured to differentially amplify an input signal and a reference voltage to generate an output signal when a clock signal has a first logic level. The amplification circuit is configured to precharge the output signal when the clock signal has a second logic level. The amplification circuit is configured to adjust a current driving force that precharges the output signal based on the reference voltage.

A display device includes a data driver for supplying a reference voltage and a plurality of data signals to each of output lines, a divider including demultiplexers for supplying the reference voltage and the plurality of data signals, which are supplied from the each of the output lines, to a plurality of data lines, corresponding to control signals, a timing controller for supplying the control signals, and pixels connected to scan lines and the data lines. The pixels located on at least two different horizontal lines are simultaneously supplied with the reference voltage.