124 results about "Voltage overshoot" patented technology

The invention provides a device for inhibiting drain-source overvoltage and overcurrent through active gate drive of a silicon carbide MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor), aiming at solving the problem of voltage or current overshoot caused by circuit parasitic parameters in a high-speed switching process of the SiC MOSFET and simultaneously considering the switching speed and energy loss balance. According to the device, drain-source voltage vdc and direct-current bus voltage of the SiC MOSFET are collected to serve as feedback signals, and gate driving voltage and equivalent gate resistance are dynamically adjusted; in a key stage (a Miller plateau switching-on period and a voltage rising period switching-off period) of a switch transient state, a gate resistance network is switched through a logic control circuit, and suppression of drain current overshoot and drain-source voltage overshoot is realized. Simulation verification shows that the device can reduce voltage overshoot by 20%-30% and current overshoot by 25%-60%, only a single voltage feedback channel is needed, the cost is obviously lower than that of a traditional multi-signal acquisition active gate driving scheme, and the device is suitable for a high-efficiency SiC MOSFET power converter.

The invention provides a method for reducing output voltage overshoot of a full-bridge DCDC converter, relates to the field of converters, and solves the technical problem that the input voltage of an isolated full-bridge DC-DC converter is unstable. The method comprises the following steps: acquiring an input voltage signal, an output voltage signal and a load current signal of the converter to form an original signal; based on the preprocessed input voltage signal, the working state of the converter is judged by combining a dynamic threshold value and a critical condition for triggering open loop of a control loop, and when it is judged that the input voltage drops, a reduced output voltage reference value is generated. When the input voltage is normal, the output voltage reference value is kept at a rated value. The reduced output voltage reference value or the voltage reference value is kept at a rated value and the preprocessed output voltage signal are subtracted, and an error signal is obtained. And taking the preprocessed load current signal as a feedforward quantity to generate a PWM driving signal. The method and the device are used for scenes with high voltage stability requirements.

The invention belongs to the field of semiconductor devices, provides a gallium nitride high-electron-mobility transistor integrated with a Schottky diode and a preparation method of the gallium nitride high-electron-mobility transistor, and aims to solve the problem that a conventional gallium nitride high-electron-mobility transistor (GaN HEMT) lacks a body diode. According to the invention, monolithic integration of the SBD and the GaN HEMT is realized through structural design, a low-impedance path is provided for reverse current, and the integration mode not only retains the original high performance characteristic of a GaN device, but also additionally endows the GaN device with reverse conduction and reverse recovery capabilities; moreover, through the structural design, the SBD can be synchronously completed on the basis of the existing GaN HEMT process, a special process or new equipment is not needed, and the cost is effectively controlled while the performance improvement is ensured; compared with an external interconnection diode scheme, parasitic inductance caused by lead bonding is eliminated, the voltage overshoot and ringing phenomena in the switching process are remarkably reduced, high-frequency switching application is facilitated, and switching loss can be greatly reduced.

The invention relates to a BOOT converter soft start circuit for a large-area-array image sensor, and belongs to the technical field of power management. The technical problem of output voltage overshoot caused by overlarge difference between reference voltage and feedback voltage when the BOOST converter is started is mainly solved. According to the technical scheme, a soft start module generates a linearly-increased soft start voltage VSS, and when the VSS is smaller than a reference voltage VREF, the VREF is replaced to be input into an error amplifier, so that a feedback voltage VFB linearly rises along with the VSS, and the surge of an inductive current is restrained. Technical effects include thoroughly eliminating voltage overshoot, maintaining optimal performance parameters of the system, providing programmable startup characteristics, enhancing system reliability, and simplifying integration complexity.

The application discloses a kind of LDO circuits, including operational amplifier, voltage division sampling circuit and power tube that are electrically connected with each other, wherein, it further includes an overshoot adjusting circuit, which is connected with operational amplifier, including capacitor, first MOS tube, second MOS tube and first mirror unit, one end of capacitor is connected with power supply, the other end is connected with the grid of first MOS tube, first mirror unit is commonly connected, the source and drain of first MOS tube are connected with operational amplifier, the source of second MOS tube is connected with power supply, an external voltage is input to the grid of second MOS tube, the drain of second MOS tube is connected with first mirror unit, and first mirror unit mirrors the current on the circuit of second MOS tube to the circuit on capacitor.The LDO circuit of the application smoothly solves the problem of overshoot of output voltage during power-on process, prevents the damage of circuit device due to voltage overshoot during operation, and improves the reliability of the entire circuit.

The application provides a permanent magnet synchronous motor weak magnetic transition area smooth transition method and system based on a reference voltage adaptive reduction, and belongs to the field of permanent magnet synchronous motor control. The method solves the problem of torque fluctuation caused by voltage overshoot in the existing voltage closed-loop weak magnetic control with a fixed reference voltage. The method comprises the following steps: obtaining a theoretical maximum torque according to a preset current limit value by simultaneously solving a torque equation and a current constraint equation; calculating torque ratio parameters and speed ratio parameters in real time; calculating a reference voltage adaptive coefficient based on an adaptive smooth transition algorithm; multiplying the adaptive coefficient by the inscribed circle voltage of an inverter to dynamically adjust the reference value of the voltage closed loop, so that smooth control of the weak magnetic transition area is realized. The method is mainly used in the fields of electric aircrafts, electric vehicles and robots.

An integrated circuit (IC) includes an array of compute units and control circuitry for mitigating supply voltage overshoot. Each compute unit contributes to an aggregate time rate of change of current drawn by the IC when transitioning between processing and non-processing states. The control circuitry is configurable to stagger when each compute unit is eligible to transition from processing data to not processing data relative to other compute units, thereby limiting the negative rate of change of current through inductive loads of the IC and preventing voltage overshoot above a maximum threshold. The control circuitry may be distributed among the compute units and configured using statically reconfigurable parameters that specify the maximum number of compute units permitted to transition concurrently and the minimum number of clock cycles between successive group transitions.

The invention discloses a power output control method and system, a storage medium and a program product, and relates to the field of power control. The method comprises the steps that firstly, a control system obtains the output voltage and the output current of a power supply end at the current moment, the feedback voltage of a load end and the set target voltage of the load end at the next moment, and a reference line impedance value is accurately calculated based on the difference value of the output voltage and the feedback voltage and the output current; then, the control system determines a compensation coefficient according to the voltage deviation absolute value and the current change rate; the virtual resistor compensates the direct current impedance of the line in a targeted manner, the voltage drop during continuous high-power output is reduced, the stable voltage quality of the load end is ensured, the dynamic damping characteristic is provided in the virtual inertia link, and the voltage overshoot or undershoot phenomenon easily occurring due to load sudden change is effectively inhibited; finally, the control system superposes the comprehensive voltage correction amount to the power supply reference voltage, thereby realizing fine adjustment of the power supply output voltage, and improving the reliability and quality of electric energy supply.

The application discloses a short-circuit recovery voltage limiting method for a three-stage direct-current generator, which detects output voltage U0 of the three-stage direct-current generator and load current i L to determine the state of the load, adjusts the output state of the three-stage direct-current generator according to the state of the load by using an asymmetric half-bridge excitation topology, detects the generation output voltage and the load current to determine characteristic states such as a short-circuit state, a short-circuit recovery state and a first voltage peak falling edge after short-circuit recovery, and closes upper and lower excitation power tubes in combination with the asymmetric half-bridge during short-circuit recovery, so that the two power tubes are opened only when the first voltage peak falls to a voltage undervoltage value after short-circuit recovery, and voltage overshoot during short-circuit recovery of the three-stage direct-current generator is limited to the maximum extent, and the safety of a power supply system is ensured.

The present application relates to the technical field of voltage stabilizing circuit, in particular to a low-cost fast transient response linear voltage stabilizer circuit, comprising an LDO main loop module and a transient response enhancement feedback circuit, the transient response enhancement feedback circuit is coupled between the error amplifier output end and the power tube gate end, a fast feedback path is constructed through two groups of coupling capacitors, directly acting on the power tube gate, and cooperating with the clamping unit to accelerate the node voltage change. The present application cancels the complex modules such as comparator and band gap reference in the traditional scheme, without relying on large off-chip capacitors, the voltage overshoot and undershoot during load jump can be effectively suppressed, the circuit structure is simple, the static power consumption is low, the layout area is small, the manufacturing cost is low, and the system reliability and integration are high.

The invention relates to a cascaded SiC power device, and relates to the field of semiconductor power devices. According to the technical scheme, through the innovative structure that the first capacitor is arranged between the gate and the drain of the Si MOS tube and the second capacitor is arranged between the gate and the source, the switching speed of the cascaded SiC power device can be accurately regulated and controlled. Specifically, compared with a traditional scheme of increasing switch delay by adjusting grid resistance and introducing extra loss by adding an external RC buffer circuit, the scheme can avoid extra energy loss and realize consideration of performance and energy efficiency while ensuring low switch delay; moreover, the scheme can effectively suppress the undesirable phenomena of voltage overshoot, ringing, electromagnetic interference and the like, remarkably reduces the voltage stress of the power device, improves the working stability of the device, prolongs the service life of the device, and enhances the overall reliability of a power electronic system. In addition, according to the scheme, the implementation mode of switching speed regulation and control is simplified, convenience is provided for designers to carry out device type selection and circuit design, and the design efficiency of a power electronic system is improved.

Disclosed in the present invention are an LDO circuit and method for mitigating output overshoot. The LDO circuit comprises a comparator. A first amplifier is connected to a low static power consumption circuit by means of a first NMOS transistor; a first voltage-dividing sampling resistor and a second voltage-dividing sampling resistor are connected to the low static power consumption circuit and generate a feedback voltage; the comparator is connected to the low static power consumption circuit by means of a fourth PMOS transistor, and compares a second reference voltage and a driving voltage that are generated inside a circuit, to control the turning-on and turning-off of a fourth PMOS transistor switch controller; on the basis of a first reference voltage and the feedback voltage, the first amplifier outputs a first voltage signal, and outputs the driving voltage by means of the first NMOS transistor and the low static power consumption circuit; on the basis of an external input voltage and the driving voltage, a second PMOS transistor generates and controls an output voltage; and the driving voltage is modulated by means of a comparator circuit to control a power transistor, so as to mitigate output voltage overshoot during slow start-up under no-load conditions and output voltage overshoot during no-load hot-swapping.

The invention provides a switching power supply control device, method and system, electronic equipment and a storage medium. The switching power supply control device is connected with a switching power supply circuit; the switching power supply control device comprises a control module, a switch module, an acceleration capacitor, a detection module and a feedback module. When the switching power supply circuit is started, the acceleration capacitor is connected to the output positive electrode of the switching power supply circuit, so that the starting overshoot of the switching power supply circuit can be inhibited through the acceleration capacitor, the load regulation rate of the switching power supply circuit is monitored, and when the load regulation rate is detected to be too large, the switching power supply circuit is started. The acceleration capacitor is considered to influence the output stability of the switching power supply circuit, and at the moment, the acceleration capacitor is disconnected, so that the output voltage overshoot can be effectively inhibited, and stable output can be maintained under different load conditions.

The application provides a variable driving parameter silicon carbide MOSFET active driving method, circuit and device. The active driving method comprises: in the on process, a power supply is controlled to apply a first weak driving level in a first time period and a first strong driving level in other time periods, the starting time of the first time period is the time when the silicon carbide MOSFET enters the Miller platform, and the ending time is the time when the drain current reaches the current overshoot peak value; in the judgment process, the power supply is controlled to apply a second weak driving level in a third time period and a second strong driving level in other time periods, the starting time of the third time period is the time when the drain-source voltage is equal to the DC bus voltage, and the ending time is the time when the drain-source voltage reaches the voltage overshoot peak value. The method has good versatility and high engineering application value, reduces the additional switching loss caused by weak driving, maintains high switching speed while ensuring the overshoot suppression effect, and thus realizes a better compromise between overshoot, loss and switching time.

The invention relates to the technical field of switching power supply control, and discloses a voltage overshoot suppression circuit and a COT control mode BUCK converter system, and the voltage overshoot suppression circuit comprises a ripple injection module, a drop detection module, a first trigger and a filtering adjustment module. The drop detection module is connected with the first trigger; the first trigger is also connected with the filtering adjustment module; the filtering adjustment module is also connected with the ripple injection module; the ripple injection module is connected with an external conversion circuit; the filtering adjustment module adjusts a time constant for generating the second ripple signal according to the first output signal, so that the descending process of the second ripple signal is matched with that of the first ripple signal, and the situation that negative ripples are injected due to the fact that the first ripple signal is lower than the second ripple signal due to slow descending of the second ripple signal is avoided. Therefore, the number of times of conduction of an upper tube of a power tube in an external conversion circuit is reduced, and the problem of output voltage overshoot of the COT control mode BUCK converter when light load jumps to heavy load is solved.

The invention discloses a starting circuit for suppressing starting overshoot, which is integrated in a DCDC converter and does not need an external expansion special device. The circuit comprises a reference voltage module, a step voltage slow rising module, a timer and an operational amplifier self-bias module. The step voltage slow rising module generates a soft start voltage signal VSTART to a first positive input end of the operational amplifier self-bias module, the reference voltage module outputs a reference voltage VREF to a second positive input end of the operational amplifier self-bias module, and a negative input end of the operational amplifier self-bias module inputs a feedback voltage VFB; the timer outputs a starting enable signal of the operational amplifier self-bias module; the soft start voltage signal VSTART generated by the step voltage slow-rise module realizes that the output voltage in the starting stage of the DCDC converter slowly rises from 0 to a rated value, and starting surge current and voltage overshoot are effectively inhibited.

A method implemented by a control circuit adaptively controls operating parameters of a switched-mode power supply to compensate for variation in circuit parameters of the switched-mode power supply, such as variation of: an inductance of an inductor, a capacitance of an output capacitor, and variation of a load capacitance coupled to an output of the switched-mode power supply. The control circuit includes a comparison circuit that determines whether or not an output voltage of the switched-mode power supply has exceeded an overshoot threshold, and a switching control circuit that has an input coupled to an output of the comparison circuit. The switching control circuit adaptively adjusts a control variable that controls one or more operational parameters of the switched-mode power supply in conformity with a relationship between a value of the output voltage and a value of the overshoot threshold in response to the output of the comparison circuit.

The embodiment of the invention provides a low-dropout linear regulator circuit, an anti-overshoot circuit and a chip. The low-dropout linear regulator circuit comprises an error amplifier, a power tube, a first resistor, a second resistor, a load capacitor, a load resistor and an anti-overshoot unit, the inverting input end of the error amplifier is used for receiving reference voltage, the non-inverting input end of the error amplifier is connected with the second end of the first resistor and the first end of the second resistor, the second end of the second resistor is grounded, the output end of the error amplifier is connected with the grid electrode of the power tube, and the source electrode of the power tube is connected with a power supply. The drain electrode of the power tube is respectively connected with the first end of the first resistor, the first end of the load capacitor and the first end of the load resistor, the second end of the load capacitor is grounded, and the second end of the load resistor is grounded; and the anti-overshoot unit is electrically connected with the power tube and is used for performing overshoot protection on the low-dropout linear voltage stabilization unit. According to the embodiment of the invention, the output voltage overshoot can be prevented when the load current suddenly changes.

The application discloses a scene-driven fast switching control device of a battery charging system and a control method thereof. A scene switching signal receiving unit receives a charging mode switching instruction; an output capacitor pre-charging unit pre-charges an output side energy storage element before charging mode switching; a charging mode switching control unit completes switching between constant current charging and constant voltage charging modes within a preset time threshold according to the scene switching signal, and a voltage overshoot rate in the whole switching process is less than a preset fluctuation threshold; a voltage smoothing unit activates a voltage smoothing mechanism in the switching process; a multi-machine synchronization unit realizes microsecond-level synchronous switching between multiple battery charging systems, and a synchronization deviation is less than 100 mu s; and a digital control unit performs switching control according to the timing of pre-charging, current limit soft starting, fast ramping and steady state. The application has a voltage overshoot rate of less than 5% in the whole switching process, and a switching time is less than 1 ms.

The invention discloses a controller and a vehicle, and relates to the field of controllers, a plurality of first terminals comprise a plurality of first sub-terminals and a plurality of second sub-terminals, at least one first sub-terminal is arranged between two adjacent second sub-terminals, a power module comprises a plurality of second terminals, the number of the second terminals is the same as that of the first terminals, and the second terminals and the first terminals are in one-to-one correspondence. The second terminals are stacked and connected with the corresponding first terminals in the thickness direction of the first terminals. Therefore, the plurality of first terminals are arranged in parallel at intervals along the first direction, and the second terminals are laminated and connected with the corresponding first terminals, so that a current path can be remarkably shortened, positive and negative current loops can be tightly attached, the loop area can be remarkably reduced, stray inductance can be remarkably reduced, and the risk of voltage overshoot can be reduced. In addition, the switching speed does not need to be reduced or a buffer circuit does not need to be added, the overall efficiency of the controller can be improved, and the production cost and complexity of the controller are reduced.

This invention belongs to the field of power electronics and DC power system protection technology, specifically relating to a boost converter topology and control method. The structure includes: a power supply and a boost inductor L. boost Main switch tube Q 1. Converter circuit breaker Q conv capacitor circuit breaker Q cap The components include a first resistor R1, a second resistor R2, a load resistor R3, a first capacitor C1, a second capacitor C2, a third capacitor C3, a first diode Dsnub1, a second diode Dsnub2, a varistor MOV, and a line inductor Lline. This invention can replace traditional DC circuit breakers, improving system operating efficiency and protection performance. It can interrupt the discharge current of the DC bus capacitor in microseconds and safely release the inductor's stored energy in milliseconds, avoiding voltage overshoot in semiconductor devices and effectively improving the safety and reliability of the DC power grid.

The invention provides a SiCMOSFET switching loss collaborative optimization method and system based on dynamic threshold regulation, and the method comprises the steps: extracting a first-order inflection point moment through analyzing a gate-source voltage transient slope evolution path, enabling the first-order inflection point moment to serve as a time anchor point to correlate with the voltage drop of a body diode so as to invert the junction temperature influence, and fusing a net gate charge attenuation trend to represent a process and an aging effect, thereby achieving the collaborative optimization of the switching loss of a SiCMOSFET. Generating a double-point asymmetric judgment point evolved along with the real-time state of the device; the carrier transport phase characteristics are combined to implement switch-on advance and switch-off delay, so that the driving action is accurately embedded into a real physical window for channel conductance establishment and depletion; therefore, turn-on triggering occurs at a critical forward moving point at which channel electrons begin to be effectively injected, turn-off triggering is maintained to the tail end of a channel carrier dominated depletion stage, the overlapping area is remarkably compressed, miller platform trailing and voltage overshoot are restrained, single-time switching energy loss is reduced fundamentally, and the performance of the device is improved. And the operation robustness of the system in a wide temperature range and a whole life cycle is improved.

The invention relates to an LLC resonant converter and a control method. The control method comprises the steps that an input voltage sampling circuit selects a working mode by sampling an input voltage; the resonance current sampling circuit outputs a resonance current feedback signal; the secondary side sampling feedback circuit samples secondary side load information and feeds back the load size; the feedback signal compensation circuit receives a sampling signal and a feedback signal, compensates a feedback voltage signal at the moment of full-bridge switching to half-bridge switching or half-bridge switching to full-bridge switching, and prevents overshoot and undershoot of an output voltage; and the PWM control circuit compares the resonance current feedback signal with the compensated feedback voltage signal to generate a first bridge arm control signal and a second bridge arm control signal so as to control the starting time of the switching tube. According to the scheme provided by the invention, the overshoot or undershoot of the output voltage caused by gain abrupt change can be effectively inhibited, the stability and reliability of the output voltage are improved, the input voltage adaptation range of the converter is expanded, and the working frequency adjustment interval is optimized.

The embodiment of the invention provides an epitaxial wafer and a preparation method thereof, and a fast recovery diode and a preparation method thereof, and the epitaxial wafer comprises a buffer layer structure located between a substrate and a drift region, and the buffer layer structure has a forward resistivity gradient in a direction away from the substrate. Therefore, a doping concentration gradient transition can be formed between the drift region and the substrate, the internal electric field distribution in the reverse recovery process is effectively smoothed, and the depletion speed of carriers is delayed, so that the reverse recovery current waveform is smoother, the softness is improved, and the turn-off voltage overshoot and electromagnetic interference are reduced.

The invention provides a high-low voltage ride-through control method and device of a grid-connected converter, a controller and the grid-connected converter. The method comprises the following steps: monitoring a power grid voltage of a common coupling point of a power grid and a grid-connected converter in real time, and judging whether the grid-connected converter enters a fault ride-through state or not according to the power grid voltage; if the grid-connected converter enters the fault ride-through state, removing a negative sequence component in the power grid voltage; and generating a driving signal for controlling the grid-connected converter based on the power grid voltage after the negative sequence component is removed. According to the method, the problems that the control deviation of a current inner loop is increased and voltage overshoot is finally aggravated due to the fact that a negative sequence component generated by an asymmetric fault or an unbalanced load invades a control loop through a voltage feed-forward link can be avoided, stable grid connection of the converter in the high-voltage and low-voltage ride-through period is guaranteed, and the off-grid risk caused by control instability is avoided.

The utility model belongs to the technical field of semiconductor devices, and discloses a circuit assembly and a power module packaging structure, first chips and second chips are mutually staggered in the transverse direction and the longitudinal direction to form step-shaped arrangement, and the staggered distances of any two adjacent chips in the transverse direction and the longitudinal direction are the same. The unique arrangement mode enables the path lengths from the grid electrode and the Kelvin electrode of each chip to the corresponding pins to realize accurate equal-length connection through the connecting pieces extending longitudinally and transversely; through the design, the parasitic inductance difference between the SiC MOSFET chips connected in parallel is remarkably reduced, so that the inconsistent conduction sequence and unbalanced current distribution caused by nonuniform inductance in the high-speed switching process are avoided; in addition, according to the technical scheme, current oscillation and voltage overshoot in the chip turn-off stage are effectively restrained, the EMI risk is reduced, and the device aging process is slowed down.

According to the control circuit of the switching power supply and the switching power supply, an output feedback signal and a reference voltage of the switching power supply are subjected to operational amplification and are compensated by a compensator to generate a compensation signal; comparing the compensation signal with a node voltage in the compensator to generate an enable signal; when the load of the switching power supply changes, the enable signal is effective, and the enable signal controls the main switching tube to perform switching action; and when the load of the switching power supply is stable, the enable signal is invalid, and the compensation signal controls the main switching tube to perform switching action. According to the invention, the load change is not easy to misjudge, the overshoot or undershoot of the output voltage is avoided when the load changes, the design difficulty is low, and the system stability can be improved.

The application discloses a low-inductance silicon carbide power module, which comprises a large-area current planning interconnection structure and a terminal direct-connection capacitor structure with a very short path, the mutual inductance between the large-area current planning interconnection structure and the conductive circuit of a ceramic substrate is used to greatly reduce the parasitic inductance in the silicon carbide power module, and the terminal direct-connection capacitor structure is used to shorten the path length from the terminal leading-out position in the power module to the external capacitor, thereby reducing the parasitic inductance of the external connecting circuit of the silicon carbide power module, reducing the parasitic inductance of the whole commutation loop, suppressing the switching voltage overshoot and oscillation, and reducing the working loss.

Devices and methods are disclosed for facilitating faster switching of silicon-based and silicon carbide-based power transistors suitable for use in electric vehicles. The disclosed techniques can minimize the impact on turn-on and turn-off losses, while reducing gate voltage and drain voltage spikes during device switching. A fast / slow cell design incorporating shielded gate MOSFETs controls gate-to-drain capacitance and gate resistances to optimize suppression of voltage overshoot.

The application is completed for the life prediction of IGBT device, aiming at the problems of low prediction accuracy, large prediction error and weak generalization ability for unknown samples in the prior art, and the technical scheme is as follows: a kind of IGBT off set-emitter voltage overshoot prediction method is proposed, the main steps are as follows: (1) the original sample is randomly disturbed, and is divided into training set and test set according to the proportion of 8:2. The input features and output labels are uniformly processed to reduce the influence of different dimensions on model training. (2) a LightGBM regression model is constructed to predict the IGBT off set-emitter voltage overshoot value. (3) on the basis of LightGBM, XGBoost is introduced to model the residual error, and the final prediction result is output through the fusion strategy. (4) the prediction result is obtained. This method is suitable for the life prediction of crimping type and welding type IGBT devices, and can provide technical support for device health evaluation.