Abstract:
A resonant converter and voltage stabilizing method thereof are provided. The resonant converter includes a converting stage circuit, a diode-rectifying stage circuit, a filter and load stage circuit, a logic circuit, a driving circuit, and an energy-recycling circuit. The method includes steps of recycling an energy from the filter and load stage circuit to the converting stage circuit when the resonant converter is light- or zero-loaded.
Abstract:
A multi-phase switching power conversion circuit has at least three phases and includes a plurality of switching circuits, a plurality of transformers, a plurality of output rectifier circuits, a resonant network and a control circuit. The resonant network includes a plurality of symmetrical terminals and a plurality of phase branches, which are connected in a multi-phase symmetrical relationship. Each of the symmetrical terminals is connected to the output side of respective switching circuits. The phase branches are connected to a resonant common terminal such that the phase branches are in a star connection. The resonant common terminal is different from the positive terminal and the first reference terminal of the input voltage source. The control circuit is connected to an output terminal of the multi-phase switching power conversion circuit and a plurality of the control terminals of the plurality of switching circuits. The switching circuits are conducted or shut off according to the output voltage under control of the control circuit, so that the electrical energy of the input voltage source is selectively transmitted to the resonant network.
Abstract:
An electrical component is disclosed, the electrical component comprising: a magnetic body having a top surface, a bottom surface, wherein at least one first conductive through hole is formed from the top surface to bottom surface of the magnetic body; and a coil disposed in the magnetic body, wherein a first end of the coil is electrically connected to one of the at least one first conductive through hole.
Abstract:
A power factor correction (PFC) circuit includes an AC power, a first bridge arm and a second bridge arm. The first bridge arm includes first and second switches connected in series with each other. A second terminal of the first switch is connected to a first terminal of the second switch, and coupled to a first end of the AC power via a first inductor. The second bridge arm includes third and fourth switches connected in series with each other. A second terminal of the third switch is connected to a first terminal of the fourth switch and a second end of the AC power. The third and fourth switches operate in ON/OFF states by use of a control signal having an operation frequency consistent with that of the AC power. The on-state resistance of the third and fourth switches is lower than that of the first or second switch.
Abstract:
A voltage regulation circuit includes a voltage conversion module, an LED driving module and a control module. The voltage conversion module is operable to receive and convert the first voltage to a second voltage. Each LED driving loop of the LED driving module has a current regulator and an LED string. The control module is operable to output a control signal according to the received input signal which reflects the current flowing through the LED driving module. The voltage conversion module regulates the second voltage according to the control signal, such that the regulated second voltage still keeps the brightness of the LED string of each LED driving loop unchanged.
Abstract:
The invention discloses a driving circuit structure for driving light-emitting loads. The driving circuit structure may include a power supplying device, a signal processing device and an impedance balancing device and a dimming control unit. The power supplying device is used for supplying an alternating current power supply. The signal processing device is used for converting the alternating current power supply into a direct current power supply, so as to drive the light-emitting loads. The impedance balancing device is used for balancing an alternating current magnitude of the alternating current power supply, so as to stabilize a direct current magnitude of the direct current power supply for driving the light-emitting loads. The dimming control unit is capable of controlling output luminance of the light-emitting loads.
Abstract:
A coil assembly includes at least one insulated wire and an electromagnetic interference shielding layer. The insulated wire is wound into a winding coil part. The winding coil part includes a first wire-outlet segment, a second wire-outlet segment and a central through-hole. The electromagnetic interference shielding layer is formed on the winding coil part for shielding the insulated wire. The electromagnetic interference shielding layer has lateral projection profile on the winding coil part. The electromagnetic interference shielding layer has a radial gap such that the electromagnetic interference shielding layer is a non-conducting loop.
Abstract:
A power factor correction (PFC) circuit includes an AC power, a first bridge arm and a second bridge arm. The first bridge arm includes first and second switches connected in series with each other. A second terminal of the first switch is connected to a first terminal of the second switch, and coupled to a first end of the AC power via a first inductor. The second bridge arm includes third and fourth switches connected in series with each other. A second terminal of the third switch is connected to a first terminal of the fourth switch and a second end of the AC power. The third and fourth switches operate in ON/OFF states by use of a control signal having an operation frequency consistent with that of the AC power. The on-state resistance of the third and fourth switches is lower than that of the first or second switch.
Abstract:
The present invention provides a high-power medium-voltage drive power cell, which comprises: a rectifier module for rectifying the three-phase AC input voltage to get a DC voltage; an IGBT (Insulated Gate Bipolar Transistor) inverter bridge connected to capacitors for converting the DC voltage into an AC voltage of which the frequency, the amplitude and the phase are adjustable; a bypass module connected to the IGBT inverter bridge for providing the bypass function when the IGBT inverter bridge works in an abnormal state; and a heat pipe heat sink having a base plate on both sides of which power elements of the high-power medium-voltage drive power cell are disposed.
Abstract:
A DC chopper comprising a control unit and a power circuit and a DC chopping method for a DFIG (doubly fed induction generator) system are provided. The input terminal of the control unit is coupled to a DC capacitor of a converter to detect a DC voltage. The power circuit includes input terminals, an overvoltage protection module, a rectifier module and output terminals. The overvoltage protection module comprises at least one discharge unit formed from a discharge resistor and a switch element, and the rectifier module is coupled in parallel to the overvoltage protection module. When a grid voltage drops, the control unit outputs a corresponding control signal to drive the switch element to be ON or OFF, and the output terminal of the power circuit absorbs a portion of rotor inrush current, so as to impose over-current protection.