34results about How to "Reduce current spikes" patented technology

A wordline driver circuit can include single stage level shifters to translate a low voltage level (VGND to Vcc) to a high voltage level (Vnwl to Vpp). A wordline driver can further include a two-stage discharge circuit to pull down a wordline from a boosted high voltage Vpp to a boosted low voltage Vnwl. A two-stage discharge circuit can include (i) a first discharge path that can pull the wordline toward a first low voltage VGND; and (ii) a second discharge path that can pull the wordline toward a lower boosted low voltage Vnwl. Initially discharging a wordline to a first low voltage can reduce the amount of charge injected into a boosted low voltage Vnwl supply. A two-stage discharge circuit can be self timed or externally timed.

The invention discloses a driving circuit of a silicon-carbide semiconductor field-effect transistor. The driving circuit comprises a PWM control circuit, a driving signal amplifying circuit, an opening circuit, a turning-off circuit, a gate current-increasing circuit and a voltage change rate control circuit. With the gate current-increasing circuit, the driving current is increased during the opening process of the SiC MOSFET and the rising of the gate-source voltage of the SiC MOSFET is accelerated, so that the opening speed of the SiC MOSFET is increased. With the voltage change rate control circuit, the Miller capacitance between the SiC MOSFET drain and gate is enhanced and the SiC MOSFET drain-source voltage change rate is reduced, so that the current spike during opening of the SiCMOSFET is reduced. After the SiC MOSFET drain-source voltage does not change, a voltage control switch is turned off to avoid the SiC MOSFET false conduction caused by the crosstalk, so that the safeoperation of the SiC MOSFET is ensured.

The invention discloses an intelligent IGBT (insulated gate bipolar transistor) constant-current driving device. The intelligent IGBT constant-current driving device comprises an isolation DC (direct current)-DC module, a PLD (programmable logic device) digital control module, a DAC (digital-to-analog converter) module, a controlled constant-current source, a voltage comparison logic circuit, a gate-level current acquisition circuit and a current comparison logic circuit. A driving power source and a driving signal of a primary side control portion provide an isolated driving power source and a driving signal for a secondary side through the isolation DC-DC module, and an alarming signal of the secondary side provides an isolated alarming signal for the primary side through the isolation DC-DC module. Output ends of the driving signals, the voltage comparison logic circuit and the current comparison logic circuit are connected with an input end of a PLD digital signal, output of PLD is connected with input of the DAC module, outputs of the DAC module and a subtraction circuit are connected with input of the controlled constant-current source, and output of the controlled constant-current source is connected with gate level of IGBT. On the basis of PLD digital control, output of a control circuit can be regulated according to parameter differences of different types of IGBTs to realize optimal control of different series and different types of the IGBTs.

The invention discloses an IGBT serial-connected composite voltage balancing circuit with grid-side and load-side control. The composite voltage balancing circuit comprises load-side and grid-side control voltage sharing circuits; the load-side voltage sharing circuit is connected in parallel between collectors and emitters of IGBTs, is composed of a resistor, a diode and a capacitor, and realizes static and dynamic voltage balancing in the load side; and the grid clamping voltage sharing circuit is connected in parallel between collectors and grids of IGBTs, is composed of a diode, a capacitor and a resistor, and can realize dynamic voltage balancing of the grids. The composite voltage balancing circuit realizes composite voltage balancing in the load side and the grid side via discrete passive devices, solves the problem of voltage imbalance due to characteristic difference of the devices and asynchronous driving signals in the IGBT switching on / off process, and ensures the working stability of the IGBT serial-connected circuit.

The invention provides an inverter welding machine which comprises a switch, a driving circuit, a main circuit, a control circuit, a pulse width modulation (PWM) output circuit and a detection circuit, wherein the switch is respectively and electrically connected with the driving circuit, the main circuit, the control circuit, the PWM output circuit and the detection circuit; and the main circuit consists of a first rectifier circuit, a filter circuit, an inverter circuit, a transformer circuit, a second rectifier circuit and an output circuit. According to the inverter welding machine disclosed by the invention, a current peak is reduced, and thus the impact on a powder grid is reduced; input current harmonics are reduced, and thus the pollution to the power grid is greatly reduced; and in addition, compared with a electrolytic capacitor, a non-polarized capacitor has the characteristic that the service life is greatly prolonged, so that the cost is saved.

The invention discloses a multi-stage soft charging control method and system for a multi-level direct-current solid-state transformer, relates to the technical field of power electronics, and solvesthe problem of how to reduce current spikes of an alternating-current side and a direct-current side when a modular multi-level direct-current solid-state transformer is started. The multi-stage softcharging control method comprises the following steps: sub-modules of a primary side MMC are charged in an uncontrolled manner; peak current is used for controlling soft charging of sub-modules of theprimary side MMC; c soft charging of sub-modules of the secondary side MMC is controlled by using phase shift modulation; the control system comprises an input source, an output source, a primary side MMC, a secondary side MMC, a current-limiting resistor Rd, a current-limiting switch Sd and a high-frequency transformer. The modular multilevel direct-current solid-state transformer sub-module capacitor charging circuit realizes quick and stable charging of a modular multilevel direct-current solid-state transformer sub-module capacitor, reduces current spikes of an alternating-current side and a direct-current side when a transformer is started, protects a power device and a high-frequency transformer in a sub-module, prolongs the service life of the capacitor, and powerfully facilitatessafe operation of a system.

The invention discloses an IGBT buffer circuit. The IGBT buffer circuit includes a clamp unit, a buffer unit and a voltage limiting unit; the clamp unit is connected between the collector of an IGBT and the buffer unit and is used for clamping the transient voltage of the IGBT when the IGBT is in a switched-on state, and preventing electric energy stored by the buffer unit from passing through the IGBT; and the voltage limiting unit is connected between the buffer unit and a load and is used for providing a discharge path to the load for the buffer unit when the IGBT is in a switched-off transient state, and voltage between the collector and the emitter of the IGBT charges the buffer unit through the clamp unit, and limiting the generation of voltage peak in a charging period. The invention further provides a PFC circuit and an air conditioner control system. The IGBT buffer circuit, the PFC circuit and the air conditioner control system of the invention are advantageous in that the IGBT buffer circuit, the PFC circuit and the air conditioner control system can reduce switching loss and protect the IGBT.

The invention discloses a soft switching method of an electric control switch of a three-phase AC input circuit. The three-phase AC input circuit comprises a soft start circuit, and after the soft start of the circuit is finished, the method comprises the following steps of: detecting the six-section wave head direct current; attracting to shut the electric control switch at any time between the zero crossing point of ab, ba sections and the voltage peak point of the ba / ab section if the C-phase of a three-phase AC is connected in series with the electric control switch; attracting to shut the electric control switch at any time between the zero crossing point of bc, cb sections and the voltage peak point of the cb / bc section if the A-phase of the three-phase AC is connected in series with the electric control switch; and attracting to shut the electric control switch at any time between the zero crossing point of ac, ca sections and the voltage peak point of the ca / ac section if the B-phase of the three-phase AC is connected in series with the electric control switch. The soft switching method of the invention begins to work at the time when the voltage of the soft start circuit is reduced to the lowest by controlling the electric control switch, thus causing the current peak on the electric control switch to be the minimum, and prolonging the service life of a relay.

The invention discloses a PWM (Pulse-Width Modulation) switching power supply control circuit with an excellent anti-electromagnetic-interference capability. The PWM switching power supply control circuit is characterized by comprising a power supply and driving module, a protection module and a multi-mode control module, wherein the power supply and driving module comprises an inner starting module, a standard voltage module, a current sampling device, an error amplifier and an output driving module; the protection module comprises an overheating protection module, an overload protection module, an overvoltage protection module and an overcurrent protection module; the multi-mode control module comprises a feedback input end, an oscillator, a load detection module for changing switching frequency, a zero-current detection circuit, a valley bottom detector for realizing a valley bottom conduction mode and a mode selector for switching a plurality of types of working modes. The PWM switching power supply control circuit disclosed by the invention adopts various methods for reducing electromagnetic interference and has a relatively good anti-electromagnetic-interference capability; a lot of peripheral circuits can be saved in an actual application process and the power supply conversion efficiency can also be greatly improved; the switching loss is reduced.

The invention discloses a variable frequency constant-current control method for an LED drive system based on a switched capacitor converter, and the method comprises the steps: taking a current Ich of a capacitor CS of the LED drive system based on the switched capacitor converter in a charging circuit as an integration input quantity, and inputting the integration input quantity into a resettable integrator; feeding back a given output current reference quantity Iref of the LED drive system based on the switched capacitor converter in the charging circuit and the whole output current Io of the LED drive system based on the switched capacitor converter to an adder-subtractor for difference solving; enabling an output signal of the adder-subtractor and an output signal of the resettable integrator to be transmitted to a comparator for comparison, and then transmitting the output signals to a D trigger, and then to a monostable multi-harmonic oscillator; enabling a signal outputted by the monostable multi-harmonic oscillator to pass through an output drive signal amplification circuit for driving a switching tube S1 and a switching tube S2 to operate, thereby achieving the constant-current output purpose and increasing the dynamic response speed of the LED drive system based on the switched capacitor converter.

The invention relates to a driving integrated circuit of a SiC MOSFET switching device. The driving integrated circuit comprises a voltage amplitude conversion module, an undervoltage protection module, a protection execution module, an output buffer module and a miller platform improvement module. According to the driving integrated circuit, a VGS platform of a power tube in a switching-on process is improved, a VDS descending speed is increased, losses are reduced, a condition that oscillation and overshoot are reduced by sacrificing a switching speed and increasing the switching losses is prevented, and meanwhile current spikes are avoided; and in addition, the driving circuit is designed into an integrated circuit so that a circuit area is greatly reduced.

The invention relates to a driving system of a GaN power device, which mainly comprises a control circuit 1, a resonant circuit and a lossless buffer circuit 3, wherein the resonant circuit further comprises a turn-on resonant circuit 2 and a turn-off resonant circuit 4, and the driving circuit is enabled to have an ability of providing asymmetrical output through the upper and lower different charging and discharging circuits. The energy stored in a capacitor C is fed back to a power supply through an inductor L in the turn-off process of a switching tube by using a resonant principle, so that the energy is enabled to be effectively utilized. Meanwhile, the lossless buffer circuit is added to slow down the rising speed of voltage, so that the GaN power device is protected to a certain extent, and a problem of high loss of the GaN power device driving circuit is solved.

Apparatus and methods for reducing noise and distortion in current digital-to-analog converters (IDACs) are described. Compensating capacitors may be connected to current sources in an IDAC. The compensating capacitors may be driven with signals derived from the output of the IDAC to cancel transient current spikes that would otherwise occur on the output of the IDAC.

The invention provides an all-digital soft start control method of an isolated Boost full-bridge converter in the technical field of power electronic switching power supplies. The method comprises the following steps: S10, outputting a PWM driving control signal with a continuously increased duty ratio D to a primary side bridge arm; S20, enabling the converter to enter a Buck mode, controlling on-off of each switching tube based on the duty ratio D, and releasing energy of a boost inductor L by using an auxiliary circuit; S30, when the duty ratio D is greater than 0.5, entering a Boost mode, controlling the on-off of each switching tube based on the duty ratio D, and controlling the boost operation of the output voltage; and S40, acquiring output voltage V1 at two ends of the load resistor R, interrupting the PWM driving control signal based on the output voltage V1, the duty ratio D and the target voltage V2, and further executing the starting subprogram to finish soft starting of the converter. The method has the advantages that: soft start of the isolated boost full-bridge converter is achieved based on the digital controller, the impact current of an inductor in the starting process is reduced, and then the reliability of circuit operation is greatly improved.

The invention discloses a self-adaptive soft drive control circuit, which comprises a basic circuit connected with an external power MOS; the self-adaptive soft drive control circuit is characterized by further comprising a drive speed detection circuit and a dynamic adjustment circuit which are connected with each other; and the dynamic adjustment circuit is connected with an external power MOS gate pole. The voltage peak of the CS pin outside the chip is detected to directly sample the current peak at the moment when the external power switch is turned on, the control loop is simple in structure, the stability problem caused by common closed-loop adjustment does not exist, the adjustment precision is high, and the adjustment of the self-adaptive adjustment end point is achieved only by adding one port to be externally connected with a ground resistor.

The invention provides an inverter welding machine which comprises a switch, a driving circuit, a main circuit, a control circuit, a pulse width modulation (PWM) output circuit and a detection circuit, wherein the switch is respectively and electrically connected with the driving circuit, the main circuit, the control circuit, the PWM output circuit and the detection circuit; and the main circuit consists of a first rectifier circuit, a filter circuit, an inverter circuit, a transformer circuit, a second rectifier circuit and an output circuit. According to the inverter welding machine disclosed by the invention, a current peak is reduced, and thus the impact on a powder grid is reduced; input current harmonics are reduced, and thus the pollution to the power grid is greatly reduced; and in addition, compared with a electrolytic capacitor, a non-polarized capacitor has the characteristic that the service life is greatly prolonged, so that the cost is saved.

The invention discloses a driving circuit of a silicon-carbide semiconductor field-effect transistor. The driving circuit comprises a PWM control circuit, a driving signal amplifying circuit, an opening circuit, a turning-off circuit, a gate current-increasing circuit and a voltage change rate control circuit. With the gate current-increasing circuit, the driving current is increased during the opening process of the SiC MOSFET and the rising of the gate-source voltage of the SiC MOSFET is accelerated, so that the opening speed of the SiC MOSFET is increased. With the voltage change rate control circuit, the Miller capacitance between the SiC MOSFET drain and gate is enhanced and the SiC MOSFET drain-source voltage change rate is reduced, so that the current spike during opening of the SiCMOSFET is reduced. After the SiC MOSFET drain-source voltage does not change, a voltage control switch is turned off to avoid the SiC MOSFET false conduction caused by the crosstalk, so that the safeoperation of the SiC MOSFET is ensured.

The invention discloses an intelligent IGBT constant current drive device, which comprises an isolated DC-DC module, a PLD digital control module, a DAC digital-to-analog conversion module, a controlled constant current source, a voltage comparison logic circuit, a gate-level current acquisition circuit and Current comparison logic circuit. The driving power and driving signal of the primary side control part provide isolated driving power and driving signal for the secondary side through the isolated DC-DC module, and the alarm signal of the secondary side provides an isolated alarm signal for the primary side through the isolated DC-DC module; The output terminals of the driving signal, the voltage comparison logic circuit and the current comparison logic circuit are connected to the input terminal of the PLD digital signal, the output of the PLD is connected to the input of the DAC digital-to-analog conversion module, and the output of the DAC digital-to-analog conversion module and the subtraction circuit is connected to the controlled constant The input of the current source is connected, and the output of the controlled constant current source is connected to the gate level of the IGBT through the driving resistor Rg. The device of the present invention takes PLD digital control as the core, and can adjust the output of the control loop according to the difference in parameters of different types of IGBTs, so as to realize the optimal control of different series and types of IGBTs.

The invention discloses an adaptive soft drive control circuit, which includes a basic circuit, the basic circuit includes an external power MOS, and a driving speed detection circuit and a dynamic adjustment circuit, and the driving speed detection circuit is used to receive the The source voltage of the power MOS determines whether to adjust the driving speed, and outputs an enabling signal. The dynamic adjustment circuit is used to receive the enabling signal and gradually change the driving current of the power MOS until the driving speed is maintained at a preset value. near the set value. The present invention directly samples the current peak at the moment when the external power switch is turned on by detecting the voltage peak of the external CS pin of the chip. The port is externally connected to the ground resistor to realize the adjustable end point of self-adaptive adjustment.

The invention relates to a DC-DC converter and a control method thereof. The DC-DC converter comprises a control circuit, a BOOST main circuit and a soft switching auxiliary circuit. An output end ofthe control circuit is electrically connected with an input end of the BOOST main circuit and the input end of the soft switching auxiliary circuit. The output end of the BOOST main circuit is electrically connected with the input end and the output end of the soft switching auxiliary circuit, and the control circuit is used for controlling zero-voltage switching-on and switching-off of the BOOSTmain circuit and controlling the zero-current switching-on and switching-off of the soft switching auxiliary circuit. According to the technical scheme, switching losses of a power device are reduced,the voltage peak and the current peak are weakened, and meanwhile an occupied space of the device is small.

The invention discloses a control method for a single-phase brushless motor. The brushless motor with the application of the control method is used in an electric tool, and the electric tool includesa position sensor, a driving circuit, and a controller. The control method includes the steps that: the controller closes a currently outputted control signal when a position signal outputted by the position sensor is changed, after a non-conduction angle T is delayed, the controller triggers the output of a target control signal to the driving circuit, and the driving circuit drives the single-phase brushless motor according to the target control signal. According to the control method, with the change of the position signal outputted by the position sensor as a command, the controller closesthe currently outputted control signal, after the non-conduction angle T, the output of the target control signal to the driving circuit is triggered to drive the single-phase brushless motor so as to reduce the current spikes in the single-phase brushless motor, the overall performance of the single-phase brushless motor is improved, and the size of an electric tool motor and the size of a corresponding control board are reduced.

A multi-stage soft charge control method and system for a multi-level DC solid-state transformer, which relates to the field of power electronics technology, and solves the problem of how to reduce the current peaks of the AC side and the DC side when the modular multi-level DC solid-state transformer is started; the described The multi-stage soft charging control method includes: uncontrolled charging of the sub-module of the primary side MMC; using peak current to control the soft charging of the sub-module of the primary side MMC; using phase-shift modulation to control the soft charging of the sub-module of the secondary side MMC; the control System, including input source, output source, primary side MMC, secondary side MMC, current limiting resistor R d , the current limit switch S d , high-frequency transformer; realizes the fast and stable charging of the sub-module capacitor of the modular multi-level DC solid-state transformer, reduces the current peak of the AC side and the DC side when the transformer is started, and protects the power devices and high voltage in the sub-module The frequency transformer increases the service life of the capacitor and is beneficial to the safe operation of the system.

The present invention relates to a DC-DC converter and a control method thereof. The DC-DC converter includes a control circuit, a BOOST voltage boosting main circuit and a soft switching auxiliary circuit, and the output terminals of the control circuit are connected to the BOOST voltage boosting circuit respectively. The input end of the main circuit is electrically connected to the input end of the soft switching auxiliary circuit, the output end of the BOOST boost main circuit is electrically connected to the input end and the output end of the soft switching auxiliary circuit, and the control circuit is used for Controlling the zero-voltage turn-on and turn-off of the BOOST step-up main circuit, and controlling the zero-current turn-on and turn-off of the soft-switching auxiliary circuit. The technical scheme of the invention reduces the switching loss of the power device, weakens the voltage peak and the current peak, and meanwhile the device occupies a small space.

A method for managing a load supplied by a converter that is itself supplied by a battery, and corresponding system. A method and corresponding system for managing a load supplied by a converter that is itself supplied by a battery comprising modules that can be switched, a capacitor being disposed between the battery and the converter. The method comprises: detecting a switching command (E01), if a switching command is detected, the converter supplies a low power to the load (E02), carrying out the switching (E03), if the switching is carried out, the converter supplies a normal power to the load (E04). The invention is applicable to the management of power trains of motor vehicles having electric or hybrid traction.

The invention discloses a bridgeless isolation type switched capacitor SEPIC PFC converter. The topological structure of the bridgeless isolation type switched capacitor SEPIC PFC converter is composed of two power switch tubes, an inductor, a transformer, five diodes and four capacitors, a bridgeless topological structure is adopted, and semiconductor loss is low. In addition, an inductor is replaced by a transformer, so that an isolation effect is achieved, the leakage inductance of the transformer is utilized, and the current peak in the converter can be effectively reduced. The high-gain bridgeless switched capacitor SEPIC PFC converter disclosed by the invention can generate an extremely high power factor and low surge current, is favorable for reducing the cost of the converter, and meets the IEC 61000-3-2 standard requirement.

The invention discloses an electric vehicle charger on-line output series-parallel connection automatic switching device, which relates to the technical field of electric vehicle chargers, and comprises at least two power supply modules, and a relay assembly and a triode assembly which are connected between any two adjacent power supply modules, the relay assembly comprises a first relay, a second relay and a third relay, and the triode assembly comprises a first triode, a second triode and a third triode. The two ends of the first relay, the second relay and the third relay are respectively connected in parallel with the first triode, the second triode and the third triode, so that the charger module can realize on-line series-parallel connection switching.

The invention discloses a frequency conversion and constant current control method of an LED drive system based on a switched capacitor converter. The capacitor C in the charging circuit of the LED drive system based on a switched capacitor converter S current I ch As the integral input quantity of , it is sent to the resettable integrator, and the LED drive system based on the switched capacitor converter is given the output current reference quantity I in the discharge circuit ref The overall output current I of the LED drive system based on the switched capacitor converter o Feedback to the adder-subtractor for difference, the output signal of the adder-subtractor and the output signal of the resettable integrator are sent to the comparator for comparison and then sent to the D flip-flop, and then enter the monostable multivibrator, The signal output from the monostable multivibrator is then passed through the output drive signal amplification circuit to drive the switch tube S 1 and switch tube S 2 , so as to achieve the purpose of constant current output, and improve the dynamic response speed of the LED driving system based on the switched capacitor converter.