609 results about "Pulse-width modulation" patented technology

The invention discloses a battery pack equalization control method and system based on multidimensional state mapping, and the method comprises the steps: obtaining terminal voltage data, working current data and surface temperature data of each single battery in a target battery pack; calculating an ohm internal resistance value and a polarization impedance value of each single battery; calculating an impedance growth rate; according to the impedance growth rate and the surface temperature data, a health state value is determined, and an aging weighting coefficient is determined; determining a polarization safety coefficient of each single battery based on the polarization impedance value; calculating a state-of-charge value of each single battery in the target battery pack, and determining a balance demand deviation degree; determining a basic equalization duty ratio of each single battery according to the equalization demand deviation degree; correcting the basic balance duty ratio to generate a target pulse width modulation duty ratio; and according to the target pulse width modulation duty ratio, controlling equalization circuits connected to the two ends of each single battery to be switched on. The battery pack equalization control efficiency is improved.

The invention discloses an energy storage converter predictive current control method based on data driving model self-learning, and belongs to the technical field of power electronic converter control. The energy storage converter is a half-bridge bidirectional DC-DC converter, and the method comprises the following steps: collecting the state quantity of the energy storage converter through a sensor in each control period, forming a data driving prediction model constructed by an input vector input neural network online parameter identification module, and outputting an initial duty ratio prediction value; constructing a value function, performing online optimization on an initial value through a gradient descent method to obtain a final optimal duty ratio, and simplifying a scene to directly use the initial value; comparing the optimal duty ratio with a carrier wave to generate a PWM (Pulse Width Modulation) signal to drive a power switch tube; actual inductive current is collected, an ideal duty ratio enabling the value function to be minimum is reversely solved to serve as a supervision signal, and the model weight is trained and updated online through a sample. The technical problem that traditional continuous set model predictive control depends on an accurate mathematical model is solved.

Disclosed is a system for zero voltage switching in a power converter with a first half-bridge and a second half-bridge. The first half-bridge has a first set of transistors and output inductor. The second half-bridge has a second set of transistors and auxiliary inductor. A current sensing means measures, at switching cycle scale, average and maximum current values of output inductor and average, minimum and maximum current values of auxiliary inductor. A voltage sensing means measures input and output voltages of first and second half-bridge. A controller is configured to compute dead times of pulse width modulation control signal of second half-bridge, generate pulse width modulation control signal of second half-bridge and to adapt dead times of first half-bridge.

The invention discloses a PCB soldering paste printing three-dimensional defect detection system based on multispectral imaging, and relates to the field of machine vision detection, and the system comprises a multispectral image acquisition module, a four-channel industrial camera based on RGB and near infrared, and a tunable LED light source array; acquiring reflection characteristic data under different penetration depths through a wavelength switching mechanism; the motion control trigger module is used for realizing positioning based on an XYZ three-axis objective table driven by a servo motor in cooperation with feedback of an encoder; a pulse width modulation signal is adopted to coordinate the moving speed of a camera shutter and a platform; according to the method, RGB and NIR four-channel imaging is combined with Beer-Lambert law modeling, so that double verification of material component quantitative analysis and three-dimensional shape reconstruction is realized, and limitation of monocular vision is avoided; structured light projection and binocular stereo matching technologies are adopted, cross-frame data alignment is realized in cooperation with an ICP algorithm, and detail defects can be better detected.

The invention belongs to the technical field of power supply control, and particularly relates to an improved linear gain digital signal control method applied to a power supply. Aiming at the problems of poor gain linearity, low control precision, slow dynamic response and insufficient adaptability to system parameter change in a wide load and wide input voltage range in the traditional digital control, the method comprises the following steps of: digitally acquiring power supply operation parameters at high precision, and introducing an adaptive linear gain adjustment module to calculate a target control gain. In addition, the method generates a pulse width modulation signal based on the corrected gain and digital operating parameters to regulate the power output, and samples quantized output feedback in real time. Through the scheme, the response speed and stability of the power supply system during transient load change can be remarkably improved, and power supply management with higher precision, higher robustness and faster dynamic response is realized, so that the overall performance of the power supply system is comprehensively improved.

The invention provides a nerve regulation and control system and method for a spinal cord ventral epidural region, and the system employs a microprocessor to generate multiple paths of pulse width modulation signals, and drives a voltage-controlled current source after amplitude adjustment. Stimulation current with adjustable frequency, pulse width and amplitude is output to act on a spinal cord ventral nerve structure. Real-time monitoring of stimulation current of each channel is realized through combination of voltage sampling and a single-pole multi-throw analog switch, feedback information of a body position, myoelectricity, pressure and other multi-mode sensors is fused, a closed-loop control mechanism is constructed, and dynamic adjustment and individualized optimization of electrical stimulation parameters are realized. The system has the advantages of being more accurate in electrical stimulation positioning, more sensitive in response, more intelligent in control and the like, and is suitable for intelligent rehabilitation intervention in scenes of spinal cord injury, cerebral palsy, neurological dysfunction and the like.

A piezo actuator system includes a piezo actuator; and a driving circuit configured to apply a pulse width modulation (PWM) voltage waveform to the piezo actuator. An envelope of the PWM voltage waveform includes a first period in which a first voltage rising with a first slope is applied, a second period in which a second voltage rising with a second slope is applied, and a third period in which a third voltage rising with a third slope is applied. The third slope is greater than the second slope.

The invention relates to a direct-hanging type energy storage inverter power module SOC equalization control method and hardware suitable for an unbalanced output current working condition, and the method comprises the steps: carrying out the state sensing of a power grid, carrying out the positive and negative sequence separation based on a double-dq coordinate system, and obtaining the amplitude and phase information of current and voltage components; generating a three-phase basic voltage reference value meeting the power demand of the power grid based on the deviation between the decoupled current component and the current instruction; according to the unbalanced working condition parameters of the power grid and the charge state difference of each phase of battery, the zero-sequence voltage injection amount required by inter-phase equalization is calculated; calculating the voltage compensation amount of each power module according to the charge state difference of each power module in the same phase; synthesizing the three-phase basic voltage reference value, the zero-sequence voltage injection quantity and the voltage compensation quantity of each power module to generate a modulation signal of each power module; a switch control signal is generated through pulse width modulation, and inter-phase and intra-phase adaptive SOC equalization control is realized; hardware is implemented based on the method.

The invention belongs to the technical field of photoelectric fusion integrated circuits, and particularly discloses a parallel PWM expansion high-precision programmable DAC structure. The adjusting module is used for adjusting the thermo-optical phase shifter according to the received digital control signal; the DAC structure specifically comprises a pulse width modulation signal generator and a current source array, wherein the pulse width modulation signal generator is used for acquiring a low-order code element from the digital control signal to generate a pulse width modulation signal, and sending the pulse width modulation signal to the current source array; wherein the current source array is used for acquiring a high-order code element from the digital control signal to generate a high-order analog signal; a low-order analog signal is generated based on the pulse width modulation signal; and the processor is also used for weighting and accumulating the low-order analog signal and the high-order analog signal to obtain an analog control signal and outputting the analog control signal. The DAC structure is high in precision and simple in structure.

The invention relates to an intelligent valve terminal control method and system for electronic injection of an aero-engine, and the method comprises the steps: obtaining multi-source state data in the operation of the engine, and carrying out the preprocessing to form a high-dimensional time sequence feature vector; a deep learning inference model is utilized to accurately identify a current working condition and predict a future evolution trend; generating an optimal fuel injection strategy based on a model predictive control and reinforcement learning mixed strategy; on-line self-adaptive correction is carried out by monitoring a comparison result of an actual response and an expected output, and an optimization instruction sequence is generated; and finally, converting the signal into a multi-channel synchronous pulse width modulation driving signal, and accurately controlling the coordinated action of a plurality of fuel injection valves. Intelligent and fine control over fuel injection is achieved, the combustion efficiency, the dynamic response speed and the operation stability of the engine are effectively improved, meanwhile, emission is reduced through multi-target optimization, and the problems that in the prior art, control lags behind, multi-valve cooperation precision is insufficient, and working condition adaptability is poor are solved.

The described techniques address issues related to conventional SPC protocols, and provides AEAD without any additional overhead in the data transfer during normal operation. An additional encryption seed transfer stage is implemented as part of the initial setup mode between the primary device and each other secondary device (e.g. sensors) for which secured SPC communications are to be performed. The secondary devices may thereafter transmit encrypted sensor data, for example, using a variety of encryption techniques, which include sponge-based algorithms.

A hybrid converter control method for offshore wind power, an apparatus, a device and a storage medium. The method comprises the following steps: S1, assigning a reference initial value for an effective value of an alternating current bus voltage of a hybrid converter, an operating angular frequency of the hybrid converter, and a reference value of an MMC direct current voltage, and acquiring an alternating current bus voltage of the hybrid converter, an effective value of the alternating current bus voltage of the hybrid converter, and an MMC direct current voltage; S2, calculating d-axis and q-axis components of the alternating current bus voltage of the hybrid converter in a dq rotating coordinate system; S3, calculating a reference value of the effective value of the alternating current bus voltage of the hybrid converter; S4, calculating a reference value of an MMC modulation voltage in the dq rotating coordinate system; S5, calculating an MMC modulation voltage in a three-phase stationary coordinate system; and S6, on the basis of the MMC modulation voltage in the three-phase stationary coordinate system, performing pulse width modulation to obtain trigger pulses for IGBTs of the MMC, thereby implementing steady-state control on the hybrid converter.

Systems and methods for cooling a datacenter (100) are disclosed. One or more circuits of a datacenter (100) cooling system can receive a speed control signal for a pulse width modulation (PWM) fan and can modify a speed control signal to output a direction control signal to a motor driver associated with a PWM fan, so that a direction control signal can enable a forward direction or a reverse direction for a PWM fan, while a speed control signal can enable a speed of a PWM fan.

The invention relates to the technical field of systems for adjusting electrical variables, and discloses an automatic adjusting system for voltage fluctuation in an electroplating process, and the system comprises a feature extraction module which is used for obtaining an original sampling signal of voltage transient change of a controlled load end and extracting voltage differential information; the logic damping operation module is used for generating a logic compensation instruction according to the voltage differential information and a preset logic damping operator; and the pulse width modulation instruction reconstruction module is used for reconstructing a carrier phase and a placeholder edge time sequence according to the logic compensation instruction to correct the duty ratio. Virtual damping vectors with opposite polarities are implanted into a digital control loop, so that the output voltage generates a damping response which is subjected to exponential attenuation along with time to suppress transient voltage oscillation; according to the method, high-frequency ringing signals caused by coupling of parasitic parameters of the power transmission line and equivalent impedance of the controlled load are eliminated, and the voltage stability of the controlled load group during frequent switching of multiple task positions is guaranteed.

The invention discloses an electromagnetic compatibility integrated protection system for an electric driving system of an electric vehicle, which relates to the technical field of electromagnetic compatibility protection and comprises a multi-dimensional parameter synchronous sampling module for acquiring an operation condition characteristic sequence of a target electric driving system in a preset time window; the space-time diagram isomorphic prediction module outputs a predicted interference frequency domain feature vector corresponding to the current control period; the collaborative anti-interference resolving module is used for respectively calculating a carrier frequency band spread spectrum instruction aiming at a bottom microcontroller and a reverse compensation injection current aiming at an active filtering loop; and the bottom hardware reconstruction execution module is used for updating a carrier frequency register of a pulse width modulation generator in the target electric driving system according to the carrier frequency band spread spectrum instruction and synchronously controlling the active filtering loop to output the reverse compensation injection current. According to the invention, the accurate pre-judgment capability of electromagnetic interference of the electric driving system of the electric vehicle and the long-term stability of full-life-cycle electromagnetic compatibility protection are improved.

The invention discloses a ripple suppression method, an energy storage power supply and a storage medium, and is applied to the technical field of ripple suppression of energy storage power supplies. The method comprises sampling to obtain an output voltage; based on the output voltage and a preset multi-resonance PR controller, a plurality of first control quantities are calculated, and the first control quantities are in one-to-one correspondence based on the frequencies of the to-be-suppressed voltage ripples; calculating a third control quantity based on the first control quantity and a preset second control quantity output by a voltage loop; and calculating the duty ratio of pulse width modulation according to the third control quantity. A plurality of first control quantities that suppress a voltage ripple of an output voltage are calculated using a multi-resonant PR controller. And then, the plurality of first control quantities are superposed on a second control quantity output by the voltage loop, so that when the voltage loop realizes voltage control, a compensation waveform opposite to the ripple waveform is generated, ripple suppression is realized, and ripples of a plurality of frequencies can be suppressed at the same time. In addition, filter capacitance does not need to be increased, and the hardware cost and the system failure rate can be reduced.

A pulse-width modulator (401) comprising a pulse generator (402) configured to generate, at a switching frequency, a pulse-width modulated waveform for synthesising an analog waveform, and a clock unit (403) configured to control the switching frequency and to, while the pulse generator (402) is generating a series of pulses that represents a single respective period of the analogue waveform, change the switching frequency such that at least one pulse in every series is generated at a different switching frequency from other pulses in that series.

Disclosed are an electrical stimulation circuit, an electrical stimulation method, an electronic device, and a storage medium, where the electrical stimulation circuit includes: a timer for timing; a pulse width modulator connected to the timer, where a first pulse signal is generated when first trigger time set by the timer is up, and a second pulse signal is generated when second trigger time set by the timer is up; a driving circuit connected to the pulse width modulator, where the first pulse signal outputs a first stimulation current, the second pulse signal outputs a second stimulation current through the driving circuit, and the first stimulation current is opposite to the second stimulation current; and a stimulation electrode connected to the driving circuit, where the stimulation electrode is in contact with a plurality of stimulation positions, and configured for randomly outputting the first stimulation current and the second stimulation current.

The invention relates to the technical field of power supply adaptation and regulation and control, particularly discloses an automatic power supply adaptation control method and system based on active detection, computer equipment and a storage medium, and is applied to power supply driving control of a safety tongs coil. An electrical parameter set and temperature data of a coil loop are collected, multi-dimensional feature vectors are extracted after filtering processing, the specification, model and working state of a coil are dynamically identified, optimal initial excitation power supply configuration parameters are matched from a pre-stored mapping table according to an identification result, a reference is determined when accurate matching is not carried out, and fine adjustment is carried out in combination with the working state. And generating a pulse width modulation excitation signal based on the initial parameter, performing closed-loop optimization on the duty ratio and the frequency, optimizing and adjusting algorithm parameters through an in-place detection signal, and performing early warning on a fault prediction model. Precise adaptation between the power supply and the coil specification and the dynamic working condition can be achieved, the braking reliability is improved, the coil service life is prolonged, the failure shutdown loss is reduced, complex installation scenes are adapted, and operation safety of special equipment is guaranteed.

The invention discloses a rapid soft start control method and device for a switching power supply. The method comprises the following steps: determining a target voltage output by a soft start preprocessing circuit in a steady state according to a preset standard voltage, a preset standard current and a load resistance value of a resistive load; determining a target duty ratio corresponding to a switching tube of the soft start preprocessing circuit in a steady state according to the target voltage and a preset input voltage of the switching power supply; a first control signal is sent to the pulse width modulation circuit, and the duty ratio of the switching tube is adjusted to the maximum duty ratio; monitoring that the real-time output voltage of the soft start preprocessing circuit is increased to the target voltage through a voltage sampling circuit; and a second control signal is sent to the pulse width modulation circuit, and the duty ratio of the switching tube is adjusted from the maximum duty ratio to the target duty ratio, so that rapid soft start of the switching power supply is realized and a steady state is reached. According to the invention, the soft start time of the switching power supply can be obviously shortened, and the switching power supply can rapidly reach a stable working state after soft start.

Electrical apparatus (20) includes an inverter (24) having input terminals for receiving DC input power and output terminals for coupling to an AC power grid. A pulse-width modulation (PWM) generator and drivers (26) drive the switches so as to control respective amplitudes, frequencies, and phases of the output current waveforms of the inverter. Control circuitry (28) receives measurements of respective time-varying voltages and currents on the input and output terminals, computes a model (40) that includes three virtual currents flowing in a synchronous machine that is emulated by the apparatus, wherein the three virtual currents are associated respectively with the three output current waveforms, and controls the PWM generator and drivers responsively to the three virtual currents so as to synchronize the amplitudes, frequencies, and phases of the three output current waveforms of the inverter with the three phases of the AC power grid.

A method and system for controlling a hybrid power system comprising a plurality of energy sources includes obtaining, by at least one processor, a plurality of state variables associated with the hybrid power system, determining a reference value for each of the state variables, and computing an error vector representing a difference between the state variables and the reference values. An integral sliding surface is generated using the error vector, and at least one control input for respective power converters is determined based on the sliding surface and a system model of the hybrid power system to cause the state variables to converge to the reference values within a fixed time independent of initial conditions. The at least one control input is applied as pulse width modulation signals to regulate distribution of energy, thereby maintaining a stable DC bus voltage and ensuring real-time operation.

The embodiment of the invention provides a multi-channel transcranial focused ultrasound regulation and control system and method based on high-frequency precise-control SPWM (Sinusoidal Pulse Width Modulation). The system is applied to the technical field of ultrasonic treatment and comprises a main control module, an ultrasonic driving module, a frequency tracking module, a power supply module and an ultrasonic transducer, the master control module is used for SPWM signal generation, driving strategy switching and frequency tracking algorithm deployment. The ultrasonic driving module is used for receiving the SPWM signal output by the main control module, amplifying and filtering the SPWM signal and then outputting a target sine driving signal to the ultrasonic transducer; and the frequency tracking module is used for realizing real-time detection and tracking of the actual resonant frequency of the transducer. According to the invention, the hardware cost of multi-channel driving is reduced; the total harmonic distortion of the driving signal is reduced, and the frequency and phase control precision is improved; multi-channel driving is realized through a single MCU, and cortical and deep brain region regulation and control are compatible; the stability of the treatment process is guaranteed while the energy utilization efficiency is improved.

The invention discloses a frequency control method of a variable-frequency power supply. The method comprises the following steps: step 1, collecting multi-source information; 2, generating a dynamic frequency reference; 3, calculating a predictive control quantity; 4, self-adaptive compensation correction is carried out; and step 5, pulse width modulation output. The state of the variable-frequency power supply is sensed comprehensively through multi-source information collection, and data support is provided for accurate control; dynamic frequency reference generation and predictive control quantity calculation are adopted, rapid and accurate frequency control is achieved, and response delay and static errors are reduced; a self-adaptive compensation correction and pulse width modulation output mechanism is constructed, the adaptability to complex working conditions is enhanced, harmonic oscillation is suppressed, compared with the prior art, the response speed, the control precision and the adaptability are remarkably improved, and stable and efficient operation of the variable-frequency power source is guaranteed.

The invention relates to the technical field of charging control, and discloses a charging current control circuit, an energy storage device and a battery management system, the circuit comprises a reference source unit, the input end of the reference source unit is connected with an external power supply port, the reference source unit is used for receiving the input voltage of the external power supply port, and the input voltage of the external power supply port is output to the energy storage device; a reference voltage is generated based on the input voltage; the input end of the operational amplifier chip unit is connected with the output end of the reference source unit and the current input port of the energy storage device, and the operational amplifier chip unit is used for receiving the input current of the current input port and generating an input control signal based on the input current and the reference voltage; and the input end of the pulse width modulation chip is connected with the output end of the operational amplifier chip unit, and the pulse width modulation chip is used for performing charging current control based on the input control signal. The accuracy of the charging current control circuit is improved.

The application discloses a kind of carbon dioxide laser pulse signal quality detection and anti-interference control method and system, it is related to the field of device using stimulated emission, this method includes: when enabling effective state indication is effective, external pulse width modulation signal is sampled, and the sequence of multiple-point sampling buffer is obtained, the rising edge and the falling edge of external pulse width modulation signal are determined, and the pulse period measurement value and the pulse width measurement value of current pulse are calculated;Determine the preset duty cycle interval to which the duty cycle of current pulse belongs, and generate a duty cycle interval flag;Measure power measurement value, and compare with the proportional threshold value generated based on current pulse width measurement value, to determine power abnormal state;When power abnormal state is abnormal, determine shielding period in preset mapping table according to duty cycle interval flag, generate protection control signal, and perform anti-interference control to laser. By implementing the present application, abnormal detection and anti-interference control of laser output in a larger duty cycle range can be realized.

The invention relates to the technical field of electric power systems, and discloses a network construction type energy storage converter control method and device and a related product. The method comprises the following steps: constructing a corresponding MPC controller based on a pre-constructed discrete state space equation of a to-be-controlled network-building type energy storage converter; the MPC controller comprises a cost function and a constraint condition; the cost function comprises a state error term; performing optimization solution on the MPC controller by adopting a preset optimization algorithm to obtain an active power reference value and a reactive power reference value when the cost function reaches the minimum; and utilizing a virtual synchronous generator module and a voltage and current double closed-loop control module to generate a pulse width modulation signal based on the active power reference value and the reactive power reference value so as to control the target network-building type energy storage converter. According to the invention, the problems of current impact, power angle instability and the like which are easy to occur in the grid-forming type energy storage converter during voltage drop can be effectively solved, and stable grid-connected operation of the grid-forming type energy storage converter under the working condition of power grid voltage drop is ensured.

The integrated circuit includes a delay monitor that monitors a delay of the data signal from the digital circuitry by generating a pulse having a width determined by the delay. In some embodiments, a delay monitor is implemented as a digital circuit that includes a pulse generator and an event generator. The delay monitor receives a data signal and a clock signal for clocking the data signal. The pulse generator generates a pulse according to the received data signal and the clock signal, wherein a width of the pulse is determined by a delay of the data signal relative to the clock signal. The event generator generates events that are temporally distributed with respect to the clock signal. As a result, the delay may be estimated based on an overlap between the event and the pulse.

The invention discloses a broadband oscillation active damping method, system and device based on MMC sub-module cluster collaboration and a storage medium, and relates to the technical field of power system stability control, and the method comprises the steps: collecting the electrical quantity of a power grid in real time, and recognizing a broadband oscillation mode and characteristic parameters through a signal processing algorithm; equivalent circuit parameters of the programmable virtual resonator are calculated, and the number of sub-modules of a sub-module cluster is determined in combination with the real-time states of the sub-modules of the modular multilevel converter; generating a control instruction according to the parameter and the oscillation component, and adjusting a sub-module pulse width modulation signal; oscillation amplitude attenuation, a damping ratio and a sub-module state are continuously monitored, adjustment is performed according to an evaluation result, and safe operation is ensured; the method can accurately suppress power grid oscillation, improves the utilization rate of the MMC device, saves the cost, is high in self-adaption, guarantees the reliable operation of the system, reduces the loss, is easy to expand and maintain due to the modular design, and improves the stability of the power system.

The invention relates to the technical field of wind driven generator control, in particular to a wind driven generator blade electric pulse deicing device thyristor control method, which comprises the following steps of: acquiring multi-dimensional data and fusing the multi-dimensional data into a blade working condition sensing data set to provide a rich and comprehensive information basis; the method comprises the following steps: acquiring blade surface icing thickness distribution data by acquiring a multi-time-sequence data training model and combining calibration data; differentiated division of energy demands is realized by dividing pulse energy demand levels and outputting a distribution matrix; the accuracy of the control parameters is improved by calculating the thyristor conduction angle adjusting quantity and the pulse width modulation parameters; low-temperature compensation correction is performed on the thyristor, so that the reliability of a trigger pulse sequence in a low-temperature environment is ensured; by executing differential electric pulse deicing operation, the deicing efficiency and pertinence are improved; the self-adaptive optimization control of the deicing process is realized by acquiring the deicing completion degree in real time and dynamically updating the regional energy density distribution matrix.