32results about How to "Reduce output current ripple" patented technology

The invention discloses a control method of an electrolytic hydrogen production rectification power supply based on a high-transformation-ratio transformer. The control method comprises the following steps of: acquiring the voltages ua, ub and uc of an alternating current bus, and acquiring an output voltage udc1 of a 6-pulse thyristor rectifier and an output voltage uinv of a single-phase H-bridge inverter; obtaining a reference phase of the a-phase voltage ua by using a phase-locked circuit; adjusting the output voltage of the 6-pulse thyristor rectifier through a control signal; determining a control signal of the single-phase H-bridge inverter according to a target voltage, and adjusting the output voltage of the single-phase H-bridge inverter to a target value through the control signal; and after a high-transformation-ratio step-down transformer is connected in series, obtaining compensation voltages ucom which are equal in amplitude and ripple voltage component and opposite in direction to achieve ripple compensation, and enabling voltages at the two ends of a load to be constant direct currents. A rectification power supply adopts a series connection structure and is isolated by a transformer, so that the rectification power supply cannot generate a circulating current and is more reliable and stable.

An on-board charger for charging a battery of an eco-friendly vehicle and a method for charging a battery using the on-board charger are provided. The on board charger reduces an output current ripple by improving a snubber circuit unit of the on-board charger for charging a battery in plug-in hybrid and electric vehicles. In addition, the on-board charger for charging a battery of an eco-friendly vehicle reduces a surge voltage generated in a rectifier diode and reduces an output current ripple by arranging two capacitors and three diodes in a transformer secondary rectifier of the on-board charger.

The invention provides a buck DC-DC converter and an electronic device. The buck DC-DC converter comprises an input unit, a first phase buck unit, a second phase buck unit, an output unit and a control unit; the input unit is used for connecting with a direct current source, and the output unit is used for connecting with a direct current load. The first phase buck unit and the second phase buck unit are connected with the direct current load; the first phase buck unit includes a first switch tube; the second phase buck unit includes a second switch tube and a third switch tube; the control unit outputs pulse width modulation signals respectively to the first switch tube, the second switch tube and the third switch tube such that the first phase buck unit and the second phase buck unit outputs a voltage alternately to the output unit. The two-phase alternate parallel technique is used herein, buck capacity of the converter is improved, voltage stress and output current ripple of a switch device are decreased, and power level of the converter is increased.

The invention discloses a three-phase controllable pulse power supply rectifier topology and a rectification method. The rectifier comprises a multi-pulse wave uncontrolled rectifier and a two-stage AC-DC converter which are connected in parallel, the multi-pulse wave uncontrolled rectifier is a three-phase bridge type rectification structure formed by diodes or thyristors, and the two-stage AC-DC converter can output a compensation current which is equal to a ripple current generated in a loop of the multi-pulse uncontrolled rectifier in magnitude and opposite to the ripple current in direction. According to the present invention, the multi-pulse wave uncontrolled rectifier is used as a main power loop, the two-stage AC-DC converter is used as an auxiliary power loop, the auxiliary power loop outputs the compensation current to compensate the ripple current generated by the main power loop, so that the low-cost high-power efficient use is achieved.

The invention discloses a three-level hysteresis current tracking inverter and a control method of the three-level hysteresis current tracking inverter. An three-level inverter bridge output end is connected with an inductor in series mode and then serves as an output end of the three-level hysteresis current tracking inverter, each voltage detecting unit respectively detects voltage between a zero level supporting point of a three-level inverter bridge and a three-level output end of the inverter, detected results are respectively fed to each driving control unit, a current detecting unit detects three-level output current of the inverter, detected results are respectively fed to each hysteresis comparison unit, three-level command current signals are respectively fed to each hysteresis comparison unit and each driving control unit, output ends of each hysteresis comparison unit are connected with corresponding driving control units, output ends of each driving control unit are connected with corresponding units, and output ends of each driving unit are connected with driving signal input ends of the three-level inverter bridge. The device and the control method can perform hysteresis tracking control on output current of the three-level inverters and have the advantages of being high in tracking accuracy, fast in speed, good in real-time and the like.

The invention relates to a staggered single-cycle control complementary current generator and a control method thereof. The invention has the advantages of small current tracking error, high tracking speed, fixed switching frequency, and the like and remarkably decreases the ripple component of the output compensation current in a staggered ripple cancellation mode. The staggered single-cycle control complementary current generator comprises a three-phase inverter bridge I and a three-phase inverter bridge II, the output ends of the two three-phase inverter bridges I and II are respectively connected in series with a current transformer group I and a current transformer group II and then respectively connected with a three-phase inductor I and a three-phase inductor II, the output ends ofthe three-phase inductors I and II are connected in parallel and then connected with a three-phase compensated power line, the three-phase inverter bridges are respectively connected with pulse driving devices which are respectively with corresponding current detection units I and II, synchronous pulse generating units, voltage parameter arithmetic elements and instruction current arithmetic elements, the current detection units are connected with the respective current transformer groups, and the two arithmetic elements are connected with corresponding detection units.

The invention discloses a control method of a DC-DC converter based on a Lyapunov function. The method comprises the following steps: S1, establishing a switching affine model of the DC-DC converter; S2, designing an expression of an error tracking switching control law based on a segmented time-varying Lyapunov matrix; S3, determining values of undetermined parameters of the error tracking switching control law by solving a linear matrix inequality; and S4, controlling the state of a switching element of the DC-DC converter through an error tracking switching control law sigma (x (k)), and further controlling the output of the DC-DC converter. According to the invention, in the related parameter solving process of the error tracking switching control law, a multi-Lyapunov function method with a segmented time-varying Lyapunov matrix and a sampling control method are adopted, and compared with a traditional common Lyapunov function method, the method has the advantages that the conservative property and complexity of related parameter solving of the DC-DC converter are reduced, the output error of the DC-DC converter is reduced, and the electric energy conversion efficiency of the DC-DC converter is effectively improved.

The invention discloses a staggered parallel DC-DC converter with a high step-down ratio. The positive electrode of a power supply is connected with one end of a first capacitor, the negative electrode of a second diode, one end of a first switch transistor and one end of a second switch transistor; the other end of the first capacitor is connected with the positive electrode of a third diode andthe negative electrode of a first diode; the positive electrode of the second diode is connected with the negative electrode of the third diode and one end of a second capacitor; the other end of a first switch transistor is connected with one end of a second inductor and the negative electrode of a fourth diode; the other end of the second switch transistor is connected with one end of the firstinductor and the negative electrode of a fifth diode; the other end of the first inductor is connected with the other end of the second inductor and one end of a load resistor; and the negative electrode of the power supply is connected with the other end of the second capacitor, the other end of the load resistor, the positive electrode of the fifth diode and the positive electrode of the first diode. The converter has the characteristics of a high step-down ratio, low output ripples, continuous input current and good voltage regulation ability.

The invention relates to a power factor correction circuit, a control system and power supply equipment, and the power factor correction circuit comprises an input bus, at least two power factor correction branches which are connected with the input bus in parallel, and a filter capacitor and a load which are connected with the two ends of the input bus in parallel, each power factor correction branch comprises an energy storage inductor, and a switch tube and a diode which are connected with the energy storage inductor, and the switch tube and the diode are respectively connected with a filter capacitor and a load; the input bus is connected with an input power supply. According to the invention, the capacity of a single energy storage inductor can be reduced, the average current stress and output current ripples of a switching device can be reduced, the service life of the switching device is prolonged, the cost of power equipment is reduced, and the working efficiency of the power equipment is improved.

The invention discloses a high-specific-power Buck circuit applied to a satellite power supply, which belongs to the technical field of space power supplies, and comprises an input end used for inputting a first voltage to a first Buck circuit and a second Buck circuit. The first Buck circuit is used for receiving the first voltage and outputting a second voltage to an output end together with thesecond Buck circuit; the first end of the first Buck circuit is connected with the input end; the second Buck circuit is used for receiving the first voltage and outputting the second voltage to theoutput end together with the first Buck circuit; the first end of the second Buck circuit is connected with the input end; the output end is used for receiving the control of the first Buck circuit and the second Buck circuit and outputting the second voltage; and the output end is connected with the second end of the first Buck circuit and the second end of the second Buck circuit. The high-specific-power Buck circuit applied to the satellite power supply provided by the invention has the characteristics of high specific power, low output current ripple, simple topological structure and highreliability.

The embodiment of the invention discloses an anti-condensation system of an enclosed bus of a generator. The anti-condensation system is used for preventing the enclosed bus from generating a condensation phenomenon. The system of the embodiment comprises a three-phase enclosed bus, an air compressor device, an anti-condensation structure, an air storage tank, an inflation control device and a compressed air storage tank. The three-phase enclosed bus is connected with the inflation control device, the inflation control device is used for controlling the pressure of gas introduced into the aircompressor device, and the inflation control device is separately connected with the anti-condensation structure and the air compressor device. The anti-condensation structure is used for maintaininga dry environment in the three-phase enclosed bus, the air inlet end of the air storage tank is connected with the air compressor device and the compressed air storage tank, and the air outlet end ofthe air storage tank is connected with the inflation control device. The air storage tank is used for storing the gas introduced into the system, and the compressed air storage tank is used for reducing the output current pulsation of an air source.

The invention discloses a control circuit of an interleaved parallel bidirectional Buck-Boost converter and belongs to the field of converters. The converter can work in a charging state or a discharging state according to actual needs, a voltage outer loop and a current inner loop generate regulating variables, and the output of the current inner loop is multiplied by a preset period T to obtain the conduction time of a switching device; according to a volt second balance theorem, required turn-off time can be calculated, so that the inductive current can be controlled to be in a critical conduction mode. According to the control circuit of the interleaved parallel bidirectional Buck-Boost converter, a high-precision high-frequency current sampling circuit and a zero-cross detection circuit can be avoided, the inductive current can be controlled to be in a critical continuous state just by sampling voltage signals and low-frequency current signals. The method has the advantage of low cost.

The invention discloses a digital high power driving power supply based on a low power consumption rectifier bridge, which comprises a low power consumption rectifier bridge, a voltage-stabilizing DC power supply module, an auxiliary power supply, a CPLD digital control module, an inversion step-up module, a feedback circuit and a comparator, wherein the low power consumption rectifier bridge, the voltage-stabilizing DC power supply module, the auxiliary power supply, the CPLD digital control module and the inversion step-up module are sequentially connected; and the inversion step-up module is also connected with the CPLD digital control module via the feedback module and the comparator in sequential connection. Based on a CPLD digital control mode, slope engraving and small character engraving can be well finished. In the case of laser cutting processing, stable power output under long-time work can be ensured. The auxiliary power supply based on a VIPer22A converter and a high-frequency power supply transformer is adopted, the waveform of output voltage is stable, and no large peak exists. The frequency response is high, control is accurate, ripples of output current are small, and a laser can be ensured to work stably and in a long time.