92results about How to "Reduce ripple voltage" patented technology

DC link capacitance in a bi-directional AC/DC power converter using a full-bridge or H-bridge switching circuit can be greatly reduced and the power density of the power converter correspondingly increased by inclusion of a bi-directional synchronous rectifier (SR) DC/DC converter as a second stage of the power converter and controlling the second stage with a control loop having a transfer function common to both buck and boost modes of operation of the bi-directional SR DC/DC converter and a resonant transfer function to increase gain at the ripple voltage frequency (twice the AC line frequency) to control the duty cycle of the switches of the bi-directional SR DC/DC stage and controlling the duty cycle of the switches of the full-bridge or H-bridge switching circuit using a control loop including a notch filter at the ripple voltage frequency.

The present invention relates to a resonant DC-DC power converter assembly comprising a first resonant DC-DC power converter and a second resonant DC-DC power converter having identical circuit topologies. A first inductor of the first resonant DC-DC power converter and a second inductor of the second resonant DC-DC power converter are configured for magnetically coupling the first and second resonant DC-DC power converters to each other to forcing substantially 180 degrees phase shift, or forcing substantially 0 degree phase shift, between corresponding resonant voltage waveforms of the first and second resonant DC-DC power converters. The first and second inductors are corresponding components of the first and second resonant DC-DC power converters.

The invention provides a low drop-out linear regulated power supply without an off-chip capacitor. The low drop-out linear regulated power supply comprises an error amplifier, a power tube output branch, a high-pass filtering network, a first charging and discharging circuit, a second charging and discharging circuit and a buffer at least, wherein the power tube output branch is connected with the error amplifier; the high-pass filtering network is used for regulating the driving capability of the error amplifier based on changes of the output voltage of the power tube output branch; the first charging and discharging circuit is used for being connected with a gate capacitor of a power tube to form a first charging and discharging path based on ripples in the output voltage of the power tube output branch, and the power tube output branch comprises the power tube; the second charging and discharging circuit is used for being connected with a gate capacitor of the power tube to form a second charging and discharging path based on transient jumps of the output voltage of the power tube output branch, the power tube output branch comprises the power tube; the buffer is connected with the power tube output branch. The low drop-out linear regulated power supply not only achieves stability in a full-load range, but also can achieve a low ripple voltage and rapid recovery capability under the circumstance of heavy-load current jumps.

A PWM/PFM control circuit has a differential time generating means for forming a differential time signal representing a differential time corresponding to a difference between the pulse width of a PWM control signal and the pulse width of a PFM control signal on condition that the pulse width of the PWM control signal is smaller than the pulse width of the PFM control signal, and the oscillation frequency of a reference signal serving as a reference for forming the PWM control signal is controlled based on the differential time signal to a low value in accordance with the differential time.

A rectifier circuit includes: a switching circuit having an input end, an output terminal and a control end, wherein the input end of the switching circuit receives an input voltage; a control circuit electrically connected to the control end of the switching circuit, wherein, when a load current is smaller than a reference current, the rectifier circuit is situated at a light-load state and the control circuit reduces a switching frequency of the switching circuit; and a filtering circuit which is electrically connected between the output end of the switching circuit and an output terminal of the rectifier circuit, and includes at least one inductive component of which a current is formed by superposition of the load current and a ripple current, wherein, when the load current is smaller than the reference current, an inductance of the inductive component increases with the decrease of the load current.

A selector sets respective phases of pulse driving signals in reverse when a proportion signal or integration signal does not exceed a threshold. Shifting the respective phases of the pulse driving signals from each other lowers the ripple voltage. When the load current increases drastically, the output voltage Vo tends to decrease remarkably because of the shortage of capacity in the power supply. In this case, when the proportion signal or integration signal exceeds its corresponding threshold, a phase control unit causes the pulse driving signals to synchronize their phases, i.e., the selector supplies the same ramp wave to the comparators, so that respective output voltages supplied from the DC voltage converter circuits attain the same phase, thereby restraining the output voltage supplied to the load from decreasing remarkably.

The invention provides a control system and a control method for a frequency interpolation pattern cascading off-line PFC-PWM switch power converter. An PFC module converts an AC voltage to a DC voltage; a control signal of a first switch block of a PFC module is generated by a PFC control signal generation module; the input current of the PFC module is adjusted and the DC voltage output by a first capacitor is steadily kept at the set value; a PWM module converts the output voltage of the PFC module to the output voltage of the control system; a control signal of a second switch block is generated by a frequency interpolation pattern PWM control signal generation module, so that the output voltage of the control system reaches the set DC voltage value; when the first capacitor is charged, the second capacitor is charged at intervals. The invention has the advantages of improving the frequency feature of the DC-DC part, reducing the ripple voltage of the capacitor and the cost, and improving the power factor adjusting coefficients of the cascading off-line PFC-PWM switch power converter.

The invention discloses an unmanned aerial vehicle flight controller attitude calculation and control method. The attitude calculation method includes a first attitude matrix obtained by fusing an accelerometer with a magnetometer, a second attitude matrix obtained by fusing a gyroscope and a third attitude matrix of the previous control period, and a third attitude matrix including high-precision attitude information obtained by fusing the first attitude matrix and the second attitude matrix. The attitude control method takes the attitude space vector as the control object, obtains the control quantity of each motor according to the third attitude matrix, and realizes the attitude control of the unmanned aerial vehicle. The attitude calculation and control method can be applied to the control of all the attitudes of the unmanned aerial vehicle, and is high in real-timeness and stable in attitude calculation and control.

In order to provide a switching regulator having high efficiency even under light load, the switching regulator is configured so that ON/OFF of a switching element is controlled by an output signal of an oscillation circuit having an oscillation frequency controlled by an output signal from an error amplifier. Thereby, the oscillation frequency can be suppressed under light load, thus reducing a switching loss.

A charge pump circuit (1) comprising first and second rectification elements (10, 11) connected in series between an input terminal (7) and an output terminal (9) and outputting a predetermined voltage from the output terminal (9) when charges are moved sequentially through these rectification elements (10, 11) and stored in an output capacitor (12). The charge pump circuit (1) further comprises an integrator (15) for integrating the difference between a feedback voltage from the output terminal (9) and a reference voltage, a boost capacitor (17) having one end thereof connected with the joint point between the first and second rectification elements (10, 11), and a clock reverser (16) having power supply side and ground side transistors (30, 31) being inputted with a clock signal (CLK) and a variable current source (32) for feeding a current dependent on the output voltage from the integrator (15) to any one of the transistors, and having its output connected with the other end of the boost capacitor (17).

The invention describes a switching power supply system for automatically regulating an operating frequency and the method. The switching power supply system has a sensing and monitoring unit connected to the computer system for detecting the operating status of the computer system and outputting a detection value, a setting unit for setting a trigger condition value, a storage unit connected to the setting unit for storing the trigger condition value, a comparator unit connected to the storage unit and the sensing and monitoring unit for comparing the detection value with the trigger condition value and outputting a comparison result signal, and a PWM switching frequency regulator unit connected to the comparator unit and the converter for receiving the comparison result signal and regulating the operating frequency of the pulse width modulation so that a converter can supply power to the computer system more efficiently.

The invention provides a charge pump circuit. The charge pump circuit comprises a group of differential complementary metal-oxide-semiconductor (MOS) switch circuits, a reference voltage negative feedback circuit, a group of N-channel metal-oxide-semiconductor (NMOS) current mirrors and a group of P-channel metal-oxide-semiconductor (PMOS) current mirrors, wherein the group of NMOS current mirrors and the group of PMOS current mirrors are respectively connected to the differential complementary MOS switch circuits and the reference voltage negative feedback circuit for providing mirror currents; and the reference voltage negative feedback circuit is connected with differential complementary MOS switches, so that the reference voltage negative feedback circuit provides feedback for the differential complementary MOS switches. Currents flowing through two groups of complementary differential MOS switches are completely matched through the feedback action of the reference voltage negative feedback circuit on the differential complementary MOS switches, so that the ripple voltage generated at an output voltage end due to unmatched current sources is effectively reduced, and the output noise performance of a phase locked loop is greatly improved.

The invention relates to the field of voltage stabilized power supply, in particular to a high-power wide-range adjustable DC linear regulated power supply, which includes a switching power input circuit, an auxiliary switch power supply circuit, the power factor compensation boost circuit, the isolated power conversion circuit of the switching power supply, the voltage and current controllable BUCK circuit and the load voltage and current display circuit. By the cooperatively connected circuit modules, the invention solves the problems of narrow voltage regulation range, small power and bulkyof the existing DC linear voltage stabilized power supply.