47 results about "Pwm modulator" patented technology

A power conversion device includes a neutral point clamped multilevel power converter and a control device. The control device includes a modulation voltage generator which generates modulation phase voltage commands using phase voltage commands and phase currents, and a PWM modulator which generates gate signals for driving the power converter, using the modulation phase voltage commands. The modulation voltage generator calculates offset voltage so that, for a middle phase in which a high-low rank is middle among the phase voltage commands for respective phases, a polarity of the phase voltage command does not become opposite to a polarity of the phase current, and superimposes the offset voltage as first common voltage on the phase voltage commands for respective phases, to generate the modulation phase voltage commands.

The invention discloses an AC voltage stabilizer dynamic regulation system based on an intelligent algorithm, and relates to the technical field of AC voltage stabilizers, and the system comprises a data collection module which is used for collecting a gate voltage waveform of an IGBT of an AC voltage stabilizer and an AC voltage instantaneous value of a power grid input end of the AC voltage stabilizer; the data processing module is used for determining a first Shannon entropy value of a rising edge and a second Shannon entropy value of a falling edge of the gate voltage according to the gate voltage waveform; determining an entropy change difference quantity between the rising edge and the falling edge according to the first Shannon entropy value and the second Shannon entropy value; determining a power grid input fluctuation quantity according to the AC voltage instantaneous value; if the power grid input fluctuation quantity is smaller than a fluctuation threshold value and the entropy change difference quantity is larger than a first preset difference threshold value, generating an inversion signal compensation waveform according to the gate voltage waveform; and injecting the inverted signal compensation waveform into a PWM modulator of the AC voltage stabilizer. According to the invention, the accuracy of identifying the real disturbance caused by the external power grid of the AC voltage stabilizer is improved.

A DC / DC converter includes a converter stage to receive an input voltage and to provide an output voltage from the input voltage in accordance with a modulated drive signal. The converter stage further provides a feedback voltage representing the output voltage. A controller circuit includes an error amplifier to receive the feedback voltage and a reference voltage and to provide an error signal based on the feedback voltage and the reference voltage. A PWM modulator receives a clock signal and the error signal and generates a modulated signal based on the clock signal and the error signal, and a logic circuit receives the modulated signal and generates the drive signal for the converter stage based on the modulated signal so that the drive signal has the same duty cycle as the modulated signal, when the duty cycle of the modulated signal is not smaller than a minimum duty cycle value.

The invention relates to the technical field of frequency converters, and discloses a circuit for suppressing current oscillation of a frequency converter, which comprises a direct current bus voltage oscillation separation unit comprising an arithmetic unit and a PWM (Pulse Width Modulation) modulator; the PWM modulator is configured to calculate the DC bus voltage by using the arithmetic unit, and modulate the calculated DC bus voltage to obtain a modulation signal and a dynamic modulation ratio; wherein the dynamic modulation ratio is a factor which reversely changes along with the fluctuation of the direct-current bus voltage; a comparator configured to compare the corrected given voltage signal and the modulation signal to output a control signal; the corrected given voltage signal is obtained by correcting the given voltage signal according to the dynamic modulation ratio. In the circuit, the fluctuation voltage affects the given voltage, so that the corrected given voltage counteracts harmonic waves of the real-time direct-current bus voltage, and current oscillation is eliminated. The invention further discloses a method and device for suppressing current oscillation of the frequency converter, the frequency converter and a computer readable storage medium.

The invention relates to an intelligent speed control method, device and equipment for an electric scooter and a storage medium. The method comprises the following steps: acquiring and filtering historical riding data of the electric scooter to obtain a time sequence characteristic matrix; constructing a multi-head time self-attention mechanism and a space cross attention mechanism to obtain a time feature vector and a space feature vector; inputting into a multi-feature fusion module for weighted fusion to obtain a fusion feature vector, and generating a target speed sequence through an intention heuristic control module; constructing a state observer to obtain a system state vector; solving and calculating an observer gain matrix through a linear matrix inequality, and constructing an outer loop speed controller and an inner loop current controller to obtain adaptive PID control parameters; and a PWM modulator is input to carry out motor control quantity calculation, a speed control execution instruction is obtained, and a motor driving signal is output. The implementation of the invention ensures the accuracy of motor control, and ensures the safe and reliable operation of the system under various working conditions.

The invention provides a power management chip adaptive modulation switching method and system under a multi-load condition. The method comprises the following steps: synchronously acquiring infrared heat flow distribution data of a chip packaging surface; performing gradient direction field analysis on the heat flow distribution data, and identifying a heat conflict region; the temperature gradient is transmitted to the bimetallic cantilever beam structure through the heat conduction path to trigger arch deformation; recombining a phase distribution sequence of the multi-phase PWM modulator by combining the arch deformation and the spatial distribution range of the thermal conflict region; marking a power supply phase covering the thermal conflict region as a high heating phase, and marking a phase away from the region as a low heating phase; and a turn-off instruction is sent to the high heating phase MOSFET driver, meanwhile, the low heating phase PWM duty ratio is increased according to the thermal conflict area temperature difference value proportion, and the total power requirement of a GPU power supply area is maintained. According to the invention, the dynamic heat dissipation efficiency and the power supply stability of the power management chip in a conflict scene between sudden calculation and a resident sensor load are improved.

The application discloses a kind of self-adaptive power energy storage converter control method and system, this method can effectively solve the problem of overvoltage and under-voltage of grid-connected point and overcharge and overdischarge of energy storage battery by controlling the adaptive charge and discharge of energy storage battery.First, the grid voltage is sampled and the effective value is processed to obtain the grid voltage effective value feedback signal U gf_rms , and it is sent to the inverting input end of voltage error amplifier, and the grid voltage reference U ref Is sent to the non-inverting input end of voltage error amplifier.The output U e Of voltage error amplifier is obtained by positive and negative limiting link U e1 Is sent to one input end of multiplier.The state signal J of range determination is obtained by the state of charge signal Soc of energy storage battery, and the other input end of multiplier is sent.The output I ref Of multiplier is sent to the non-inverting input end and inverting input end of current regulator respectively with the charging current sampling signal I bf Of energy storage battery.The output of current regulator is used as modulation signal, and it is sent to PWM modulator.

A control device includes a current detector that detects a stator current flowing between a voltage application unit and a stator winding of a rotating machine; a control unit that computes a voltage command value that is a command value for a stator voltage to be applied to the stator winding on the basis of the stator current and a rotor position serving as position information of a rotor of the rotating machine; a PWM modulator that performs on-off control of switching elements of the voltage application unit so that a smoothed value of the stator voltage matches the voltage command value; and a position estimator that estimates, on the basis of the voltage command value and the stator current, the rotor position through a filter that removes a frequency component of a fundamental frequency of rotational speed of the rotating machine.

The utility model discloses a DV detection device of a DC brush motor, and aims to solve the problems that a piezoresistor of a conventional DC brush motor is fragile, easy to crack in the production process and difficult to distinguish in appearance, and especially after the motor is assembled, the piezoresistor is in the motor, and the quality of the piezoresistor is difficult to judge. The detection device comprises a motor tester, an oscilloscope, a PWM modulator and an insulating bottom plate, the output end of the motor tester is connected with the oscilloscope, the input end of the motor tester is connected with the PWM modulator, and a first conductive base and a second conductive base are installed on the upper surface of the insulating bottom plate. According to the utility model, the direct current brush motor is placed between the first conductive base and the second conductive base, PWM modulation voltage is adopted to drive the direct current brush motor to rotate, and the voltage dependent resistor of the direct current brush motor has the characteristic of consuming electric energy, so that the change of PWM average voltage can be monitored; therefore, whether the piezoresistor is good or not can be judged through the voltage change.

The invention relates to the technical field of soft start control of resonant converters, in particular to a soft start control method of a CLLC resonant converter with a short-circuit protection function, which comprises the following steps: S1, establishing a time domain model of the CLLC resonant converter; s2, calculating an output frequency based on the actual output of the CLLC resonant converter through a PI controller; s3, building a gain-minimum frequency curve based on the time domain model of the CLLC resonant converter, and obtaining the minimum switching frequency based on the voltage gain of the CLLC resonant converter; s4, determining the switching frequency based on the output frequency and the minimum switching frequency; and S5, a driving signal is calculated based on the switching frequency through a PWM modulator, and the CLLC resonant converter is driven, so that the peak resonance current of the CLLC resonant converter does not exceed a set value. According to the invention, the peak resonance current of the CLLC resonant converter can be limited not to exceed the set value, and the peak current control is realized in the starting and operating processes, so that the peak of the resonance current can be accurately limited under all working conditions.

A self-configurable modulator and method of modulation that reconfigures PWM drive signals provided to a cascaded multilevel converter in response to fault information indicating failure of any of multiple submodules of multiple phases of the cascaded multilevel converter. The modulator includes a reference voltage limiter configured to limit amplitudes of reference voltages based on the fault information, a zero-sequence voltage adjuster configured to calculate at least one zero-sequence voltage from the fault information and to add each zero-sequence voltage to each of multiple modulating signals of the phases to provide adjusted modulating signals, and a carrier signal comparator configured to realign carrier signals based on the fault information and to compare the realigned carrier signals with the adjusted modulating signals to provide reconfigured PWM drive signals.

The invention discloses a control algorithm for resonance suppression of a grid-connected inverter, and the algorithm comprises the following steps: S1, collecting and filtering three-phase voltage and three-phase current signals inputted by the inverter; s2, performing Clark conversion and Park conversion on the input voltage and current; s3, performing phase locking on the power grid through a phase locking link and estimating the phase and frequency of the voltage of the power grid; s4, extracting a high-frequency component of the voltage signal and processing the high-frequency component; s5, performing current loop control, and outputting a voltage compensation amount; and S6, calculating an instruction voltage, taking the calculated instruction voltage as the input of a PWM modulator, and outputting a PWM signal to a driving circuit through the PWM modulator so as to control the on-off of a switching tube in the grid-connected inverter. According to the method, the virtual parameters of the system are adjusted, so that the resonant frequency of the filter is separated from the working frequency band, the output of the grid-connected inverter is optimized on the whole, the method better adapts to the working condition of a power grid, and resonance is more effectively inhibited.

A kind of power amplifier of handheld mutual inductor tester, comprising: PWM modulator, switching power amplifier circuit and filter circuit;Input signal waveform is converted into SPWM wave by PWM modulator, after being amplified by switching power amplifier circuit, using filter circuit to restore the amplified SPWM wave into analog waveform;Switching power amplifier circuit includes two isolation components, two drive chips, four MOS tubes, four diodes, four freewheeling diodes, two bootstrap capacitors and four resistors, every two MOS tubes are connected in series to form a bridge arm, a freewheeling diode is connected between the drain and source of each MOS tube, the positive and negative power supply ends of a bridge arm are connected with positive supply voltage and power ground respectively, and the positive and negative power supply ends of another bridge arm are connected with power ground and negative supply voltage respectively.The utility model avoids the high voltage peak of power amplifier, thereby eliminating arc and most electromagnetic interference.

The present invention relates to the technical field of wireless communications. Disclosed in the present invention is a power amplifier. The power amplifier comprises a signal input end, a radio frequency amplifier and a signal output end which are electrically connected in sequence, and an average power tracking circuit. An input end of the average power tracking circuit is used for connecting a power supply and receiving an output signal of an external host computer, an output end of the average power tracking circuit is connected to an input end of a radio frequency amplifier, and the average power tracking circuit is used for converting, on the basis of a received target voltage value, a power supply voltage output by the power supply into a preset voltage to supply power to the radio frequency amplifier. The average power tracking circuit comprises a voltage conversion circuit, a comparator, a loop filter circuit, a PWM modulator, a voltage divider circuit, a pulse circuit, and a first inductor. By switching the characteristics of the loop filter, the present invention enables the power supply to achieve both fast establishment and high-precision output, thereby allowing a working voltage of the amplifier to be as low as possible, and further reducing power consumption of the power amplifier.

The present invention relates to a ZVS switching digital power amplifier based on H-bridge topology, comprising a DC regulated power supply module, a bridge chopper module, a transformer isolation module, an output rectifier filter module, a control module, a duty cycle loss compensation module, a switch tube drive module and an auxiliary power supply. The duty cycle loss compensation module is used to pre-distort the external input signal to be amplified to compensate for the duty cycle loss problem of the H-bridge circuit, and its output is connected to the PWM modulator of the control module; the duty cycle loss compensation module includes an addition circuit, which performs addition operation on U1 and U2, U1 is the external input signal, and U2 is a distorted voltage with the same monotonicity as the external input signal. U2, as a distorted voltage with the same monotonicity as the input signal, is superimposed on the external input signal after passing through the addition circuit. The present invention has the characteristics of high efficiency, excellent quality and low distortion.

The application relates to a D-class audio power amplifier bias voltage processing method, a circuit and a D-class audio power amplifier. The method comprises the following steps: setting multiple fine adjustment options for a feedback resistor at the differential ends of a D-class power amplifier; determining the feedback resistor setting with the minimum bias voltage in the chip factory test and burning the OTP to complete coarse adjustment of the bias voltage; after the coarse adjustment of the bias voltage is completed, dividing a PWM signal generated by a PWM modulator into two signals, processing one of the two signals through a delay unit, and then performing logical AND operation on the other signal to output a fine-adjusted PWM signal; and the fine-adjusted PWM signal is used to drive a loudspeaker after passing through a switching amplifier and a low-pass filter. The method can overcome the bias voltage caused by the deviation of the device process.

A power converter arrangement (1) comprises a multi-level power converter (10) of the neutral-point clamp type and a control arrangement (20). The control arrangement (20) comprises a modulation voltage generator (21) that generates modulation phase voltage commands (Vua*, Vva*, Vwa*) using phase voltage commands and phase currents, and a PWM modulator (22) that generates gate signals (Gu, Gv, Gw) to drive the power converter (10) using the modulation phase voltage commands (Vua*, Vva*, Vwa*).The modulation voltage generator (21) calculates an offset voltage (VX) such that - for a middle phase where the high-low rank is in the middle among the phase voltage commands for the respective phases, the polarity of the phase voltage command is not opposite to the polarity of the phase current, and the offset voltage (VX) is superimposed as the first common voltage on the phase voltage commands for the respective phases, thus generating the modulation phase voltage commands (Vua*, Vva*, Vwa*).

A differential amplifier circuit comprising a PWM modulator for generating a PWM signal representative of a difference between the first and the second staircase like reference signals and the digital input signal, a DM-IDAC for receiving the PWM signal and providing a first and second differential mode current, a CM-IDAC for receiving the PWM signal and providing a common mode current, first and second loop integrators, and first and second comparators; each loop integrator comprising virtual ground node terminal for receiving the differential mode current, the common mode current, and a feedback signal from an output stage of the differential amplifier circuit via a feedback loop, and integrator output terminal for providing loop integrator output signal proportional to an integral of the signals received at the virtual ground node terminal, the comparators receiving the loop integrator output signal, triangular reference signal, and providing drive signal to output stage.

The application discloses an alternating-current voltage stabilizer dynamic adjustment system based on an intelligent algorithm, and relates to the technical field of alternating-current voltage stabilizers.The system comprises a data acquisition module, which is used for acquiring a gate voltage waveform of an IGBT of an alternating-current voltage stabilizer and an alternating-current voltage instantaneous value of a power grid input end of the alternating-current voltage stabilizer; and a data processing module, which is used for: determining a first Shannon entropy value of a rising edge and a second Shannon entropy value of a falling edge of the gate voltage according to the gate voltage waveform; determining an entropy change difference amount between the rising edge and the falling edge according to the first Shannon entropy value and the second Shannon entropy value; determining a power grid input fluctuation amount according to the alternating-current voltage instantaneous value; if the power grid input fluctuation amount is smaller than a fluctuation threshold value and the entropy change difference amount is greater than a first preset difference threshold value, generating a inverse-phase signal compensation waveform according to the gate voltage waveform; and injecting the inverse-phase signal compensation waveform into a PWM modulator of the alternating-current voltage stabilizer.The application improves the accuracy of real disturbance identification caused by an external power grid of the alternating-current voltage stabilizer.

The invention relates to a distributed autonomous large signal stability control method suitable for a more-electric aircraft power supply system, and belongs to the field of power electronic DC-DC converter control. Using the sampled current and voltage values to design a required state-space equation of the Boost converter; designing a nonlinear expansion disturbance observer based on the state-space equation, and designing an improved droop controller considering the nonlinearity of the constant-power load by using an output value of the nonlinear expansion disturbance observer; designing a sliding mode surface of integral sliding mode control based on a sliding mode control theory, and designing a control law based on the sliding mode surface; the control law is inversely transformed to obtain the value of the duty ratio of the actual control quantity converter, the value is used as input, a switching signal is adjusted through a PWM modulator to serve as a driving signal of a converter switching tube, and the output voltage of the converter is adjusted through real-time control over the duty ratio. The method is used for achieving direct-current bus voltage stabilization and accurate power distribution when a power supply system is provided with a constant-power load and encounters large signal disturbance.

The present invention discloses a method for differential optical communication applicable to underwater, including step S1: The PWM modulator digitally encodes the signal level emitted by the signal source and drives the cold and warm LEDs to send corresponding signals according to the duty cycle of the dual light sources. Step S2: The dual light sources emitted by the cold and warm LEDs are adjusted into parallel light beams under the action of a lens. Step S3: The dual light sources passing through the waterway pass through a filter to filter out interfering light, and then pass through a lens to focus the diverging light beam into a photodetector. Step S4: The electrical signal converted by the photodetector enters an amplifier for amplification processing. Step S4: The amplified electrical signal enters a PWM demodulator to be restored to a modulation signal. This method can be applied to the field of underwater optical communication. There is no need to measure the absolute value of the received light intensity, only the color of the received light needs to be measured, and attention is paid to the relative ratio of the light intensities of the dual light sources, solving the problem of large attenuation of LED light underwater, extending the communication distance, and reducing the bit error rate.

The present invention is in the field of basic electronic circuitry, in particular of a digital signal processor for streaming audio applications, more in particular a pulse-width modulator, an integrated circuit comprising said electronic circuit, and a device comprising said electronic circuitry or said integrated circuit, such as an audio device.

The invention relates to the technical field of power electronics, in particular to a switching delay measurement and compensation method and device for a converter, and the method comprises the steps: determining the delay time according to the time difference between a driving signal triggering moment and an output voltage edge detection moment; judging a turn-on edge or a turn-off edge according to the sign symbol of the bridge arm current so as to determine a compensation direction; and correcting the original PWM modulation degree to generate a compensated PWM modulation degree, and inputting the compensated PWM modulation degree into the PWM modulator so as to enable the PWM modulator to adjust the power device. According to the method, the compensation mode is directly judged by measuring the time difference between the output voltage pulse edge of the converter and the change of the driving signal and combining the bridge arm current symbol, the principle is simple, measurement is accurate, complex modeling is not needed, the calculated amount of delay measurement is reduced, the method can be deployed on a low-power-consumption DSP / MCU platform in real time, and the real-time performance of the converter is improved. And the measurement and compensation effects of the switch delay of the low-power-consumption platform are improved.

The invention discloses a secondary ripple suppression circuit applied to an energy storage system and a control method, and relates to the technical field of power electronic converters, and the circuit comprises a filter capacitor C1, a filter capacitor C2, a filter capacitor C3, a DC bus support capacitor Cdc, a power switch tube S1, a power switch tube S2, a filter inductor LA, an energy storage power supply Us, a grid-connected inverter and a control circuit. And the voltage reference value of the filter capacitor C3 is obtained, is subtracted from the voltage of the filter capacitor C3 and then is input into the controller, and modulation signals of the switching tubes S1 and S2 are obtained through the PWM modulator. The secondary ripple suppression circuit provided by the invention replaces a traditional LC passive filter, realizes complete absorption of secondary ripples, greatly reduces the size of a filter device required in the circuit, and improves the power density of a system.

The PWM modulator comprises a capacitor C1, a capacitor C2, a resistor R1, a resistor R2, a resistor R3, a chip U1A, a chip U1B and a triode Q1, one end of the capacitor C1 is connected with the resistor R1, the resistor R3, the resistor R4, the resistor R5, a potentiometer VR1 and a power supply VCC, the other end of the resistor R1 is connected with the resistor R2, the resistor R6 and a pin 5 of the chip U1B, the other end of the resistor R6 is connected with the other end of the capacitor C1, a capacitor C3 and a grounding end, and the triode Q1 is connected with the capacitor C1. According to the utility model, chip control is not needed, the hysteresis function of the comparator is ingeniously utilized to set the frequency of the sawtooth wave, and the amplification functions of the adjustable potentiometer and the triode are utilized to set a comparison threshold value for the comparator and compare the sawtooth wave to output PWM, so that not only can the frequency be modulated, but also the duty ratio of the PWM can be modulated. The method can be widely applied to electronic control products needing PWM adjustment.

A differential amplifier circuit is provided. The circuit includes a PWM modulator for generating a PWM signal representative of a difference between the first and the second staircase-like reference signals and the digital input signal, a DM-IDAC for receiving the PWM signal and providing a first and second differential mode current, a CM-IDAC for receiving the PWM signal and providing a common mode current, first and second loop integrators, and first and second comparators; each loop integrator comprising virtual ground node terminal for receiving the differential mode current, the common mode current, and a feedback signal from an output stage of the differential amplifier circuit via a feedback loop, and integrator output terminal for providing loop integrator output signal proportional to an integral of the signals received at the virtual ground node terminal, the comparators receiving the loop integrator output signal, and triangular reference signal.

The present invention discloses a preset time feedback controller of a dual active bridge circuit in the field of power electronics technology, comprising: a time conversion law for inputting a preset time t p , output scale transformation coefficient m ( t ); time scale transformation law, used to input the scale transformation coefficient m ( t ), System Error e ( t ), output scale error signal Z ( t ), the system error e ( t ) is the sampling signal of the output voltage x ( t ) and the expected voltage x d The difference between the input and output voltages; feedback control law, used to input and output voltage sampling signals x ( t ), output scale transformation coefficient m ( t ), the rate of change of the time scale transformation coefficient, and the output scale error signal Z ( t ), System Error e ( t ), the expected voltage change rate and non-negative parameters α , output control signal u ( t ) The dual active bridge circuit is controlled by a PWM modulator and a driving circuit. The present invention transforms and reduces the time stability analysis of the output voltage error of the dual active bridge circuit, and uses the design concept of feedback control to realize a preset time feedback controller of the dual active bridge circuit.

The invention discloses a bidirectional DC-DC feedforward control system based on energy storage. The system comprises an input sampling module, a feedforward control module, a PWM modulation module and a power conversion module. The input sampling module is used for acquiring an input voltage and an output voltage in real time, processing the input voltage and the output voltage acquired in real time to obtain a processed input voltage and a processed output voltage, and transmitting the processed input voltage and the processed output voltage to the feedforward control module; the feedforward control module is used for generating a duty ratio correction signal according to the change of the processed input voltage and output voltage and transmitting the duty ratio correction signal to the PWM modulator; the PWM module is used for receiving the duty ratio correction signal, generating a corrected duty ratio signal and transmitting the corrected duty ratio signal to the power conversion module; and the power conversion module is used for outputting voltage according to the corrected duty ratio signal.

The present application describes a time coded modulator circuit (200), and in particular, describes a PWM modulator suitable for use in a class D amplifier. A forward signal path receives a digital input signal (Din) and outputs an output PWM signal (Sout) and includes a first PWM modulator (101). A feedback path provides feedback to an input of the first PWM modulator (101). The feedback path includes an ADC (203) that receives a first PWM signal (Sa) derived from the output PWM signal. The ADC (203) includes a second PWM modulator (401) that generates a second PWM signal (Sb) based on the first PWM signal. A controller (201) controls the second PWM modulator so that a PWM carrier of the second PWM signal matches a PWM carrier phase and frequency of the output PWM signal.

A current application unit includes a load element, a switching element, and a shunt resistor connected in series between both terminals of an assembled battery, and a drive control unit of the switching element to apply an alternating current having a predetermined frequency to the assembled battery. The drive control unit includes: a PWM modulator for generating a drive signal; a PDM modulator for generating the drive signal; and a switching unit for switching between a first drive state for driving the switching element by the drive signal generated by the PWM modulator and a second drive state for driving the switching element by the drive signal generated by the PDM modulator.