131results about How to "Reduce switching loss" patented technology

The invention relates to a control method of a boost-buck type power supply converter, and the power supply converter comprises an inductor, a first switch connected between the input end of the power supply converter and the first end of the inductor, a second switch connected between the first end of the inductor and the grounding end, a third switch connected between the second end of the inductor and the grounding end, and a fourth switch connected between the second end of the inductor and the output end of the power supply converter; and the control method is characterized in that the control method comprises the following steps: detecting voltage at the input end and the output end and load current at the output end for deciding whether the power supply converter performs the operation in the buck mode, the first boost-buck mode, the second boost-buck mode or the boost mode; and controlling the first, the second, the third and the fourth switches during the first and the second boost-buck modes.

The invention relates to a control circuit for a buck-boost power supply converter, which is used for providing a control signal to drive a buck-boost power level, so that input voltage is converted into output voltage, wherein the buck-boost power level comprises an inductor and at least two switches connected to the inductor. The control circuit is characterized by comprising a feedback circuit, an error amplifier, a dynamic work period generator and a driving circuit, wherein the feedback circuit detects the output voltage and generates a feedback signal; the error amplifier is connected with the feedback circuit and amplifies a difference value between the feedback signal and reference voltage to generate an error signal; the dynamic work period generator generates a first signal according to a detection signal after being started; and the driving circuit is connected with the error amplifier and the dynamic work period generator, and determines a control signal according to the error signal and the first signal. The control circuit and a control method for the buck-boost power supply converter have the advantages that: a switch witching order is optimized; the switching loss is reduced; the efficiency is improved; and output ripples are reduced.

The invention relates to a power semiconductor device having a plurality of switching elements connected in parallel. The power semiconductor device (200) possesses a first power semiconductor element (Q1), a second power semiconductor element (Q2) and a driving control part (100). The driving control part (100) enables the first and second power semiconductor elements to switch to a conductive or stop state according to the conduction or stop instruction reveived from the exterior. Specifically, the condition that the first and second power semiconductor elements (Q1, Q2) switch to the conduction state simultaneously and the condition that the one of the first and second power semiconductor elements (Q1, Q2) switches to the conduction state and then the other switches to the conduction state can be switched through the driving control part (100). The driving control part (100) enables one of the first and second power semiconductor elements (Q1, Q2) to switch to the stop state and then the other switch to the stop state according to the stop instruction.

The present invention provides a quasi-resonant control circuit of power supplies and the control method . The present invention utilizes a control circuit formed by simple electric components and the control method to control a power transistor to conduct when the power transistor and a transformer is at zero voltage level, so as to reduce the switching loss when the conduction of the power transistor is conducted.

The invention discloses a switched power supply conversion device capable of improving conversion efficiency and a method. A direct-current power supply is enabled to be connected with a load through a power supply converter. The power supply converter is provided with more than one power switch. A first frequency is output by a pulse width modulation controller and is used for controlling the switching frequency of the power switch. A load current is detected by a current detector. A frequency conversion signal is produced by adding a judging condition and is sent to the pulse width modulation controller. The pulse width modulation controller is enabled to output a variable second frequency to adjust the switching frequency of the power switch. The judging condition is that the load is judged to be a light load or a heavy road according to the load current. When the load is the light load, the second frequency is reduced to reduce switching loss of the power switch. When the load is the heavy load, the second frequency is improved to reduce ripples of the load current of the heavy load. And then cost of the switched power supply conversion device is reduced, and conversion efficiency is improved as well.

The invention discloses a control circuit of a buck-boost power converter, which is used for generating a control signal for manipulating a buck-boost power level and also used for converting an input voltage into an output voltage, and is characterized by comprising a feedback circuit, an error amplifier, a waveform generator, a frequency controller, a frequency generator, a pulse width modulation comparator and a gate driver. The control circuit and control method of the buck-boost power converter have the advantages of improving the stability of the buck-boost power converter, reducing the switching loss of the buck-boost power level and improving the efficiency of the buck-boost power converter.

The invention relates to a control circuit of a flyback converter. The flyback converter comprises a transformer and a power switch connected with the primary side of the transformer. The control circuit switches the power switch to convert an input voltage of the transformer into an output voltage. The control circuit comprises a sampling and sustain circuit, a compensation circuit and a pulse width modulation circuit and is characterized in that the sampling and sustain circuit is used for obtaining the variable quantity of a sensing signal in the predetermined time, and the sensing signal is the function of the input voltage; the compensation circuit compensates a first feedback signal with the variable quantity of a inductance current signal to generate a second feedback signal changing with the input voltage, and the first feedback signal is the function of the output voltage; and the pulse width modulation circuit is used for determining the working time of the power switch according to the sensing signal and the second feedback signal.

A driving device, which controls the conduction and disconnection of a power switch element (200), has: an on-side circuit (110), which conducts the conduction action of the power switch element; and an off-side circuit (120), which performs an off-circuit open action; and the temperature detection part (D) detects the temperature. At least one of the on-side and off-side circuits has: a current path for supplying or deriving a gate current of the power switching element; and a switch circuit (SW1-SW5, SW6-SW10) for switching the gate current . The switching circuit temporarily changes the gate current based on the temperature of the power switching element when switching the gate current.

The invention consists of an input capacitor, a main inductance and a main switch module that includes a main switch connecting to a resonant capacitor, an auxiliary switch connecting in parallel to main inductance. The main inductance consists of an auxiliary switch, a resonant inductance and a resonant diode whose cathode is connected with main switch, a main diode and an output capacitor. A driving signal is inputted from a driving circuit to make soft switch between main switch and auxiliary switch.

The invention relates to a single-inductor multi-output power converter which is characterized by comprising an inductor, a first switch, a second switch, a third switch and a fourth switch, wherein the inductor is provided with a first end and a second end, the first end of the inductor is connected with the input end of the power converter; the first switch is connected between the first end and the second end of the inductor; the second switch is connected between the second end of the inductor and an earth terminal, the third switch is connected between the second end of the inductor and the first output end of the power converter; and the fourth switch is connected between the second end of the inductor and the second output end of the power converter. The single-inductor multi-output power converter and a control method thereof have the advantages of reducing the conduction loss, the switching loss and the gate drive loss and improving the efficiency of the power converter.

The invention relates to a constant-current circuit with the characteristics of voltage compensation and zero potential switching. The constant-current circuit is a single-switch inverse magnetic converter, and comprises a control circuit, a detection resistor, a transformer, a partial voltage compensation circuit and a primary side power switch, wherein the control circuit acquires the primary side current information of the transformer by using the detection resistor, and can acquire a compensation signal from an input voltage by using the partial voltage compensation circuit, and control the threshold voltage of the primary side power switch according to the compensation signal, so that the peak voltage of the primary side current can be fixed at a reference voltage due to the compensating action of the compensation signal, and the output current of the constant-current circuit is kept in a constant state. The constant-current circuit provided by the invention has the advantages that under the conditions of not using a secondary constant-current detection circuit and a feedback circuit, all necessary information can be obtained at the primary side only by using cheap electronic components and very simplified circuit layouts, and a constant output current can be generated in a wide-area input voltage state.

A DC / DC converter containing the integrated magnetic component and the synchronous rectification circuit includes the input and output ends connected to DC voltage and loads, the integrated magnetic component, the auxiliary coil, the switch circuit and the synchronous rectification circuit. The auxiliary coil is composed of the primary and the secondary side coils to be as the filtering inductance. The switch circuit connected to the input end electrically switches the DC voltage to the outputs, providing the pulsate output to the primary side coil. Thus, in the first time period, the positive pulsate voltage stores the energy into the primary side coil and in the second time period, the negative pulsate voltage releases the energy of the primary side coil.

An electric motor arrangement comprising an electric motor having a rotor, a stator, a first coil set and a second coil set. The first coil set is arranged to form a first sub motor with a control device being arranged to control current in the first coil set to generate a first torque on the rotor. The second coil set is arranged to form a second sub motor with the control device being arranged to control current in the second coil set to generate a second torque on the rotor. The first sub motor is arranged to have a first torque efficiency profile and the second sub motor is arranged to have a second torque efficiency profile. A controller is provided to determine a first torque value generated by the first sub motor and a second torque value generated by the second sub motor in response to a requested torque demand based on a required torque efficiency profile for the electric motor.

This drive control device (32A, 32B, 52, 54, 56, 61, 62, 71, 72) of two semiconductor elements (1A, 1B) having a diode structure (6) and a transistor structure (5) having a powered electrode (15, 18) in common is provided with: a current detection means (7A, 7B, 25, 59, 60, 68) that outputs a current detection signal of the semiconductor elements; and a first control means (27) that, when it has been determined that current is flowing in the forward direction of the diode structure in the semiconductor element during the period that an on command signal is being input to the semiconductor element, outputs a gate drive signal from the point in time that a first time has elapsed to the point of time a second time has elapsed relative to the point in time that a subsequent off command signal is input. The first time and second time are pre-set in a manner such that an arm short-circuit does not arise between the two semiconductor elements.

The invention is suitable for the field of power supply, and provides a switch direct-current boosted circuit, a boosted device and an LED illuminating system. The switch direct-current boosted circuit comprises an inductor L1, an inductor L2, a diode D, a capacitor C, a resistor R1, a resistor R2, a MOS tube Q and a switch control unit. Due to the addition of the new inductor in the switch direct-current boosted circuit, the problems of large switch loss, small amplitude of voltage rise and the like in the prior art are solved, so that the switch direct-current boosted circuit improves the work efficiency and the amplitude of output voltage rise.

A fuel cell vehicle capable of improving energy efficiency by reducing switching loss is provided. The fuel cell vehicle includes: a fuel cell that generates direct current power; inverters which respectively include switching elements and convert the direct current power generated by the fuel cell into alternating current power; a diode that prevents current from flowing from the inverters toward the fuel cell; a step up / down DC / DC converter that adjusts the voltage of the cathode side of the diode; a voltage control part that controls the step up / down DC / DC converter, thereby controlling current output from the fuel cell; and a stop and idle determination part that stops the supply of air to the fuel cell, thereby stopping idling of the fuel cell. The voltage control part reduces the voltage of the cathode side of the diode as the voltage of the fuel cell is reduced by activating the stop and idle determination part.

The invention provides a manufacturing method for a trench-type power semiconductor, which comprises the following steps: firstly, providing a substrate, and defining a drain region in the substrate; then, forming a gate trench in the substrate; subsequently, forming a dielectric layer covering the inner surface of the gate trench; then, forming a clearance wall in the gate trench, wherein the clearance wall covers the dielectric layer located on the side wall of the gate trench; then, forming a plug structure at the bottom part of the gate trench, wherein the plug structure is located in a space defined by the clearance wall; then, removing the redundant clearance wall by utilizing the dielectric layer and the plug structure as masking; subsequently, removing the redundant dielectric layer by utilizing the etched clearance wall as the masking to enable the inner surface of the upper section of the gate trench to be bared outside; then, keeping the etched clearance wall, and directly forming a gate dielectric layer covering the inner surface of the upper section of the gate trench; and subsequently, forming a gate polycrystalline silicon structure in the upper section of the gate trench.

The invention discloses a production method of a groove-type power semiconductor with a low grid charge and a structure thereof. The production method is characterized by comprising the following steps of: providing a first conductive type semiconductor substrate and forming a first conductive epitaxial layer and a second conductive type body area on the first conductive type semiconductor substrate; and forming a plurality of grooves; forming a first insulating layer on the second conductive type body area and on the lateral surface of each groove; forming a polysilicon side wall on the sidewall of each groove and exposing one part of the bottom surface of the groove; filling a dielectric structure into each groove; filling polysilicon above the dielectric structure of each groove; forming a metallic silicide on the polysilicon, wherein the metallic silicide is a first phase composition; and converting the metallic silicide from the first phase composition into a second phase composition. The invention can improve the switching speed and achieve the effect of reducing the switching loss.

In described examples of synchronous rectifiers and flyback converters (100), integrated circuits (101) and operating methods, a first switch (S1) is turned on to allow current to flow for a first time period (Tl) in a first direction in a transformer primary winding (108) responsive to a first switch voltage (VDSl) transitioning below a first threshold (VTHl), and a second switch (S2) is turned on for a second time period (T2) after the first time period (Tl) to transfer energy from a secondary transformer winding (122) to drive a load (125). In the same converter cycle, the second switch (S2) is again turned on for a third time period (T3) in response to a second switch voltage (VDS2) transitioning below a second threshold (VTH2) at one of a series of troughs of a resonant ringing voltage waveform across the second switch (S2), to cause current flow in a second direction in the primary winding (108) to discharge a capacitance (CSl) of the first switch (SI) to cause the first switch voltage (VDSl) to transition below the first threshold (VTHl) to initiate a subsequent converter cycle.

A flyback converter includes: a transformer including a primary winding and a secondary winding; a first switch coupled to the primary winding; a first control module configured to control the first switch; a second switch coupled to the secondary winding; and a second control module configured to control the second switch, such that the second switch operates in an ON state during a first time period and during a second time period which follows the first time period, and such that a current flowing through the secondary winding has a direction during the second time period opposite to that during the first time period.

The invention relates to a manufacture method of a trench type metal-oxide semiconductor device. On a grid dielectric layer, a first polycrystalline silicon layer is deposited along the inner wall of a grid trench. Then, a first conductivity type dopant is implanted to the first polycrystalline silicon layer located at the bottom of the grid trench. Subsequently, a second polycrystalline silicon layer doped with a second conductivity type dopant is deposited to cover the first polycrystalline silicon layer. Subsequently, a high-temperature process is applied to enable the dopants in the firstpolycrystalline silicon layer and the second polycrystalline silicon layer to diffuse, and thereby, a first conductivity type first doping area and a second conductivity type second doping area whichare arranged at the bottom of the grid trench are formed.

The invention relates to a device for reducing standby power consumption of a display device, the display device comprises a power supply system which is used for controlling power transmission through a power changeover switch of a power supply controller, and an image zooming device which is used for receiving power supply voltage from the power supply system, and the device is characterized in that the device comprises a power supply monitoring circuit and an optical coupler, wherein the power supply monitoring device is used for monitoring the power supply voltage under the control of a mode signal during the standby mode, and accordingly producing a control signal; the optical coupler is connected with the power supply monitoring circuit and used for converting the control signal to an enable signal, and sending the enable signal to the power supply controller so as to enable or close the power supply controller. The device and the method for reducing the standby power consumption of the display device have the advantages of reducing changeover loss, reducing the power consumption and maintaining that the power supply voltage is sufficient to lead the image zooming device to operate normally.

The invention relates to the technical field of chemical gas separation and liquefaction, and provides a helium ultralow-temperature purification and liquefaction system. The system comprises a purification unit, a liquefaction unit, a pre-cooling unit and a cold transfer unit, wherein the liquefaction unit communicates with the purification unit through a gas supplementing channel, and the cold transfer unit is connected between the purification unit and the liquefaction unit; the purification unit comprises a raw material helium inlet pipe, a first purification heat exchanger first flow channel, a low-temperature adsorber, a second purification heat exchanger first flow channel, an ultralow-temperature adsorber, a second purification heat exchanger second flow channel, a first purification heat exchanger second flow channel and a high-purity helium outlet pipe which are sequentially connected through pipelines; and a working temperature interval of the low-temperature adsorber is a liquid nitrogen temperature zone, and a working temperature interval of the ultralow-temperature adsorber is 25-40K. According to the invention, through two-stage adsorption of the low-temperature adsorber and the ultralow-temperature adsorber of the purification unit, different impurities in raw material helium are respectively purified in different temperature zones, so that the helium switching loss in a purification process is reduced, and the helium extraction rate is improved.

The invention discloses a control circuit used for controlling a switching type voltage stabilizer in a buck-boost converter. The switching type voltage stabilizer comprises a first switch, a second switch, a third switch and a fourth switch. The control circuit comprises an error detector, a triangular wave generator, a comparator, an oscillator and a control signal generator. The error detector is used for generating error signals corresponding to output voltage of the switching type voltage stabilizer. The triangular wave generator is used for generating triangular wave signals. The comparator is used for comparing the error signals with the triangular wave signals to generate comparison signals. The oscillator is used for generating oscillation signals. The control signal generator is used for controlling operation of the first switch, the second switch, the third switch and the fourth switch according to the comparison signals, the oscillation signals and time-impulse signals and used for enabling the switching type voltage stabilizer to be switched between a boosting mold and a voltage reduction mode and not to be operated in a buck-boost mode. The control circuit can prevent the switching type voltage stabilizer from entering the buck-boost mode, therefore, at most two switches of the switching type voltage stabilizer can be switched at the same time, and switching loss of the buck-boost converter can be effectively reduced.

The invention relates to a D type amplifier with a second-order noise filtering circuit. Two differential output ends form a two-order feedback loop respectively with a first differential amplifier and a second differential amplifier so as to provide a higher high frequency attenuation value, therefore, the noise and other nonlinear elements of the first differential amplifier and the second amplifier are fast attenuated to improve the overall distortion noise ratio; in addition, after respectively synthesized by the first differential amplifier and the second differential amplifier, the distortion components contained in output signals of the differential output ends are amplified in the way of second-order difference, thereby effectively improving over all loop gain and forming a high-gain system. And moreover, the differential output signals of the D type amplifier can be corrected more finely after being subjected to second-order gain processing.

The invention relates to a push-pull type inverter and a drive method thereof. The push-pull type inverter comprises a transformer, a first inductance, a second inductance, a first switch and a second switch. The primary side of the transformer is provided with a first winding and a second winding. The first switch and the second switch are alternatively accessed according to a first control signal and a second control signal. After the first switch is accessed, the first inductance, the first switch, the first winding and a DC power supply form a first series loop; while after the second switch is accessed, the second inductance, the second switch, the second winding and the DC power supply form a second series loop. When the first control signal is changed from an enabling level into an unable level, the first inductance couples energy to the second inductance to lead the voltages at the two ends of the second switch to be reduced to a second voltage from a first voltage before a second control signal achieves an enabling level.

The invention discloses an ended output type D-class amplifier of a double-feedback differential circuit, comprising a gain amplifier, a second-order noise filtering circuit, two comparators, a logic circuit, two half bridge circuits and an inverter, wherein two groups of half bridge circuits are matched with the inverter to manufacture differential signals with complementary phases; then, the second-order noise filtering circuit is matched to form a double-feedback differential circuit by a forward and backward output signal with the amplifier and the gain amplifier so as to eliminate the noise of output signals; and finally, a better SDNR value is provided.

The invention provides a power converter control circuit with a deep burst mode. The control circuit comprises a load detection circuit and a pulse wave width regulating circuit. The load detection circuit generates a switching control signal according to a feedback signal which is associated with a load state of a power converter. The pulse wave width regulating circuit generates a switching signal according to the switching control signal and the feedback signal and adjusts an output of the power converter. When the load state of the power converter is an extremely light load state, the control circuit executes the deep burst mode and switches the switching signal for only once in every deep burst cycle. Therefore, switching loss is reduced and power consumption of the power converter is reduced similarly.