12results about How to "Improve light load efficiency" patented technology

The invention discloses a switching converter and a zero-cross detection circuit and method thereof, a chip and a display device, and the zero-cross detection circuit comprises a comparator which is used for comparing the voltage of a switching node with the output voltage of the switching converter to obtain a first comparison signal; the turn-on time control circuit is used for generating a turn-on time control signal according to the first comparison signal; and the adjustable delay circuit is used for adjusting the conduction duration of the synchronous switching tube in each switching period according to the conduction time control signal, so that the light load efficiency of the switching converter is improved.

The invention relates to the technical field of power conversion, and particularly discloses a modulation method and system of a converter, equipment and a medium. The converter comprises at least two H bridges and a multi-winding high-frequency isolation transformer. The modulation method of the converter comprises the following steps: setting modulation parameters; on the basis of the modulation parameter, modulating the converter by using a preset modulation strategy; wherein the set modulation parameters are as follows: different duty ratios and different out-shift ratios are respectively set for the first half cycle and the second half cycle of each switching cycle during modulation of the converter, and phase-shift zero-voltage sequences with different duration proportions are respectively added when the first half cycle and the second half cycle of each switching cycle are ended; therefore, the equivalent switching frequencies of the first half period and the second half period of each switching period are reduced by different proportions. By adopting the method and the device, when modulation input parameters change, the delay of power transmission is small, the precision is high, and in addition, the method and the device are simple and easy to implement, strong in robustness, strong in practicability and high in light load efficiency.

This invention relates to a method for improving the light-load efficiency of a synchronous rectifier chip. The method involves monitoring the voltage V between the output terminal K and the input terminal A of the synchronous rectifier chip. KA The V KA This reflects the change in load current; when the V KA When the voltage drops to the first preset voltage, based on V KA = -Is×Rdson is used to dynamically pre-adjust the Vgs drive voltage to counteract the Vgs voltage drop caused by the decrease in load current Is. KA The change extends the turn-on time of the synchronous rectifier chip; Rdson is the on-resistance of the MOSFET inside the synchronous rectifier chip; the dynamic pre-adjustment processing of the Vgs drive voltage includes: controlling the reduction of the Vgs drive voltage, utilizing the characteristic that Rdson increases as Vgs decreases in the MOSFET, and maintaining Vgs. KA The voltage remains constant.

The present invention discloses a resonant control device and a resonant control method. The resonant control device includes a feedback controller and a processor. The feedback controller receives a reference voltage and an output voltage, and uses the reference voltage to perform voltage compensation on the output voltage to generate a control parameter. The processor receives the control parameter and generates a pulse modulation signal based on the control parameter and a switching parameter to drive the resonant converter to adjust the output voltage. Each pulse modulation signal has a maximum frequency and a minimum frequency, and the maximum frequency corresponds to the switching parameter. When the control parameter is greater than or equal to the switching parameter, the pulse modulation signal adjusts the frequency according to the control parameter and the switching parameter, or controls the resonant converter to operate at a fixed time in each cycle of the pulse modulation signal to avoid switching losses of the resonant converter.

The application discloses a control method and system of a charging module and a charging system. The method comprises the following steps: collecting the operating parameters of the charging module; calculating the comprehensive discriminant value of the coupling multi-factor composite working condition according to the input voltage, output current, module temperature and battery state of charge; adjusting the power distribution ratio of the battery and the energy storage unit according to the comprehensive discriminant value; judging whether the charging module needs to switch the working condition according to the input voltage and output current and outputting the corresponding control signal to control the charging module; solving the first switching frequency with the maximum efficiency of the charging module as the target, adjusting the first switching frequency according to the current working condition to obtain the optimal switching frequency; performing adaptive PI adjustment on the current loop according to the output current to output the optimal switching duty ratio; and controlling the charging module according to the optimal switching frequency and the optimal switching duty ratio. The application enables the charging module to maintain high efficiency and stable operation within a wide input, wide output and wide load range.

The invention relates to the technical field of switching power supplies, and discloses a two-stage active power factor correction circuit and a switching power supply in order to solve the problems of low power factor and high harmonic pollution caused by the fact that the input of the switching power supply is alternating current. The circuit comprises an electromagnetic interference filter, a rectifier bridge, a PFC booster circuit, an LLC half-bridge resonance compensation circuit and a controller which are connected in sequence. The PFC booster circuit is used for boosting the voltage output by the rectifier bridge to the high-voltage direct-current bus voltage; the LLC half-bridge resonance compensation circuit is used for converting the high-voltage direct-current bus voltage output by the PFC booster circuit into stable low-voltage direct current required by a load by adjusting the switching frequency of the LLC half-bridge resonance compensation circuit; the controller is used for controlling the working mode of the PFC booster circuit according to the magnitude of the output current of the LLC half-bridge resonance compensation circuit; meanwhile, the output voltage of the LLC half-bridge resonance compensation circuit is sampled, and the switching frequency of the LLC half-bridge resonance compensation circuit is adjusted according to feedback of the output voltage. By adopting the circuit, the power utilization efficiency of power equipment is improved, and harmonic interference is reduced.

The application provides a power supply control method, device and system. The power supply control method comprises the following steps: collecting output current of the power supply system, determining a load rate according to the output current; determining a first number of boost branches in which a boost module works and a second number of voltage regulation branches in which a voltage regulation module works according to the load rate; determining target boost branches and target voltage regulation branches according to the first number and the second number; controlling conduction of the target boost branches and the target voltage regulation branches; and outputting an output signal of the power supply to the load after boosting and voltage regulation. The application can improve the light load efficiency of the power supply system.

This invention discloses a wide-range radio frequency power conversion system based on an asymmetric hybrid structure and hybrid modulation. It adopts an input parallel, output series architecture, consisting of a main power regulation module and several auxiliary power modules. The main power regulation module includes a front-stage Buck-Boost converter and a rear-stage dual-parallel full-bridge resonant unit, possessing fine voltage and phase adjustment capabilities. The auxiliary power modules are simplified full-bridge units, responsible only for discrete power switching. The system employs a hybrid modulation strategy, utilizing phase-shift control of the main power module in the low-power range, DC bus voltage regulation of the main power module in the medium-power range, and full-bridge / bypass mode switching of the auxiliary power modules in the high-power range, achieving smooth and continuous adjustment from zero to rated power. This architecture, through optimized design of resonant network parameters and utilization of the internal resonant circulating current generated by the main module in phase-shift state, ensures zero-voltage switching (ZVS) operation across the entire range, significantly reducing system hardware costs and control complexity while significantly improving system efficiency in power back-off state.

The present application relates to a kind of current mode-based fixed-frequency PWM controller and control method, belong to analog integrated circuit design field.The fixed-frequency PWM controller includes: filter and feedback module, error amplification and compensation module, voltage current conversion module, first difference module, second difference module, clock generator, PWM trigger and drive module and switching power stage.The present application utilizes the current information of the output VCOMP voltage of error amplification and compensation module, using voltage current conversion module and difference module, so that light load when fixed-frequency PWM controller automatically enters light load variable frequency, its circuit structure and control logic are simple, and light load efficiency is high, PFM entry point can be predicted, and additional operational amplifier is not needed to do PFM management, circuit simplicity is high, with strong portability and lower difficulty of implementation.

The invention provides a power supply circuit and an AMOLED display device. The power supply voltage comprises a power level module comprising a first inductor, a second inductor, a first group of switching tubes and a second group of switching tubes, a first end of the first inductor is connected with a first switching node, a second end of the first inductor is connected with a second switching node, the first group of switching tubes are arranged between a first power supply input end and a plurality of positive power supply output ends, and the second group of switching tubes are arranged between a second power supply input end and a plurality of negative power supply output ends; the first end of the second inductor is connected with the second reference ground, the second end of the second inductor is connected with the third switching node, and the second group of switching tubes are arranged between the second power supply input end and the negative power supply output end; and the logic control module is used for controlling the first group of switch tubes or the second group of switch tubes. According to the power supply circuit, the negative power supply voltage can be generated without using a negative voltage charge pump in the circuit, so that the power supply circuit can be suitable for relatively wide input and output voltage ranges and has extremely high practicability and compatibility.

The utility model discloses a kind of high voltage input LLC control circuit, including control unit, isolation unit, upper switch device, lower switch device, sampling unit and resonance unit, sampling unit includes capacitor C8 and capacitor C9, the first end of capacitor C8 is as the first input end of the sampling unit, the second end of capacitor C8 is connected with the first end of capacitor C9 and is as the output end of the sampling unit, the second end of capacitor C9 is as the second input end of the sampling unit, sampling unit is used to output to the control unit after voltage voltage reduction voltage reduction, so that the control unit controls the upper switch device conduction when rising edge disappears, and control lower switch device conduction when falling edge disappears.The utility model can reduce the power loss of sampling unit, improve the efficiency of circuit, reduce the occupied space of sampling unit, while can improve voltage sampling effect, avoid the system control defect caused by uneven voltage division.

This invention discloses a composite soft magnetic powder core and its preparation method. FeSiAl magnetic powder is added to a mixture of phosphoric acid and ethanol, stirred, and then dried to obtain insulating FeSiAl powder. Tetraethyl orthosilicate and anhydrous ethanol are added to FeNi magnetic powder, stirred, and then diluted with ammonia solution dropwise while stirring. After drying, insulating FeNi powder is obtained. The insulating FeSiAl and FeNi powders are mixed in a certain proportion to obtain composite metal magnetic powder. The composite metal magnetic powder is sieved and granulated, then a resin binder and zinc stearate are added, pressed into a green body, and annealed at high temperature to obtain the finished FeSiAl / FeNi composite powder core. Through the above methods, this invention provides targeted insulating coating for FeSiAl and FeNi magnetic powders, adjusts the permeability of the two magnetic powders, and achieves adjustment of the DC bias curve of the FeSiAl / FeNi composite powder core. This improves its anti-saturation capability under light load conditions, thereby improving light load efficiency and solving the problem of easy saturation of components in high-power applications.