17 results about "Pwm modulator" patented technology

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 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 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.

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 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.

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 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.

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 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 invention relates to a three-phase shift regulation and control method for a CLLC resonant converter, and the method comprises the steps: monitoring an input voltage, an output voltage and power in real time: obtaining an actual input voltage, an actual output voltage and an external input target output voltage through the sampling of a hardware sampling circuit, and measuring the actual output voltage and an output current; an external voltage loop calculates a voltage error, and a current reference is obtained through the voltage loop, so that the voltage of the load / battery is kept at a target value; an inner current loop calculates a current error, and a power control quantity and a second output are output through the current loop; actual input voltage is measured and enters a table look-up module through a gain block, a table look-up LUT is carried out to obtain three phase shift parameters, the three phase shift parameters are input into a PWM modulator, and a PWM waveform is generated; the output end of the PWM modulator is connected with the CLLC converter to realize stable output, the optimal phase shift angle combination can be determined in real time, so that the comprehensive efficiency of the CLLC resonant converter in a full working range is maximized, and the problem of control performance bottleneck in the prior art is solved.

The invention relates to a D-type audio power amplifier bias voltage processing method and circuit and a D-type audio power amplifier. The method comprises the following steps of: setting a plurality of fine tuning options for feedback resistors at two differential ends of a D-type power amplifier, determining the feedback resistor with the minimum bias voltage in a chip delivery test, and programming OTP (One Time Programmable) to finish coarse tuning of the bias voltage; after the rough adjustment of the bias voltage is completed, a PWM signal generated by the PWM modulator is divided into two paths of signals, one path of signal is processed by a delay unit and then is subjected to logic and operation with the other path of signal, and a precisely adjusted PWM signal is output; and the finely adjusted PWM signal is used for driving a loudspeaker after passing through a switching amplifier and low-pass filtering. The method can overcome bias voltage caused by deviation of a device process.

The invention belongs to the technical field of photovoltaic grid connection, and discloses a unified monitoring system and method for input side capacitance and direct current bus side capacitance of a photovoltaic inverter. The unified monitoring system comprises a power control unit, a PWM regulator, a voltage regulator and an ESR monitoring unit. The unified monitoring method comprises the steps that the power control unit is adjusted to be in a measurement mode, output voltage and current of the photovoltaic array are sampled and sent to the power control unit, a photovoltaic voltage reference is generated and sent to the in-phase end of the voltage regulator, and output voltage of the photovoltaic array is sent to the anti-phase end of the voltage regulator; the output of the voltage regulator is used as a modulation signal to control the on-off of a switching tube of the boost converter through a pulse signal generated in the PWM modulator; and the ESR monitoring unit is used for estimating the ESR of the input side capacitor and the DC bus side capacitor Cf on line according to the output voltage of the photovoltaic array, the modulation signal and the DC bus voltage. According to the method, the photovoltaic inverter does not need to be off-grid, and the method has the advantages of low cost, autonomous monitoring, unified monitoring and the like.

A control device includes: a current detector that detects a stator current flowing between a voltage applicator and a stator winding of a rotary machine; a controller that computes a voltage command value based on the stator current and a rotor position, the voltage command value being a command value of a stator voltage applied to the stator winding; a PWM modulator that generates a gate signal such that a value obtained by smoothing the stator voltage matches the voltage command value, and to use this gate signal to control turning on and off of switching elements provided in the voltage applicator; a voltage integrator that computes a voltage integration value by integrating the gate signal; and a position estimator that estimates the rotor position based on the voltage integration value and the stator current.

The present invention is in the field of underlying electronic circuits, in particular to digital signal processors for streaming audio applications, more particularly to pulse width modulators, integrated circuits comprising said electronic circuits, and devices (e.g., audio devices) comprising said electronic circuits or said integrated circuits.

This application relates to pixels, display devices including pixels, and electronic devices including display devices. A pixel includes: a light-emitting element through which a driving current flows; a light-emitting element driver that generates the driving current based on a pulse-width modulation (PWM) signal; and a pulse-width modulator that generates a PWM signal based on first data bits to a k-th data bit. The PWM modulator includes: a data writer that writes first data bits to a k-th data bit in response to a scan signal; a PWM controller that stores first data bits to a k-th data bit and sequentially outputs first data bits to a k-th data bit in response to a clock signal; and a PWM signal generator that generates a PWM signal in response to the first data bits to a k-th data bit and a transmit signal.

The invention discloses a differential amplifier circuit. Comprising a PWM modulator for generating a PWM signal representing a difference between first and second stepped reference signals and a digital input signal, a DM-I DAC for receiving the PWM signal and providing first and second differential mode currents, a CM-I DAC for receiving the PWM signal and providing a common mode current, first and second loop integrators, and first and second comparators; each loop integrator includes a 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 an integrator output terminal, the integrator output is configured to provide a loop integrator output signal proportional to an integration of a signal received at the virtual ground node, and the comparator receives the loop integrator output signal, a triangular reference signal, and provides a drive signal to the output stage.