An apparatus includes a controller configured to generate a PWM signal for controlling a power switch of a forward converter, a bias switch and a bias capacitor connected in series and coupled to a bias winding of the forward converter, and a comparator having a first input connected to the bias capacitor, a second input connected to a predetermined reference and an output configured to generate a signal for controlling the bias switch to allow a magnetizing current from the bias winding to charge the bias capacitor when a voltage across the bias capacitor is less than the predetermined reference.

An apparatus includes a controller configured to generate a PWM signal for controlling a power switch of a forward converter, a bias switch and a bias capacitor connected in series and coupled to a bias winding of the forward converter, and a comparator having a first input connected to the bias capacitor, a second input connected to a predetermined reference and an output configured to generate a signal for controlling the bias switch to allow a magnetizing current from the bias winding to charge the bias capacitor when a voltage across the bias capacitor is less than the predetermined reference.

The present disclosure provides a circuit control method and a circuit control apparatus, which are applied to a hybrid flyback circuit. The method includes: determining an acquisition time point according to a turn-on alternating duration of a first MOS switch and a second MOS switch on a main side of the hybrid flyback circuit and a preset time coefficient; acquiring a midpoint voltage between the first MOS switch and the second MOS switch according to the acquisition time point to obtain a first voltage signal; and adjusting negative excitation current in the hybrid flyback circuit according to a comparison result of the first voltage signal and a preset voltage value, so that the negative excitation current meets zero voltage switching of a primary-side switch of the hybrid flyback circuit.

Provided is a power converter in which a magnetic core of a noise filter can be prevented from magnetic saturation and the noise filter can be downsized. A noise filter 140 provided in a power converter includes: a magnetic core 1 formed with a single through-hole 1A and forming a closed magnetic circuit; first wiring 11 having one end 81 connected to a power conversion circuit and the other end drawn out from the second opening 3, and running through the through-hole 1A from one first opening 2 to the other second opening 3; second wiring 21 having one end connected to the other end of the first wiring 11 and the other end 82 drawn out from the first opening 2 as a filter output end, and running through the through-hole 1A from the second opening 3 to the first opening 2; a first capacitor 41 provided between the ground and a connecting portion 31 of the first wiring 11 and the second wiring 21; and the second capacitor 51 provided between the other end 82 of the second wiring 21 and the ground.

Provided is a power converter in which a magnetic core of a noise filter can be prevented from magnetic saturation and the noise filter can be downsized. A noise filter 140 provided in a power converter includes: a magnetic core 1 formed with a single through-hole 1A and forming a closed magnetic circuit; first wiring 11 having one end 81 connected to a power conversion circuit and the other end drawn out from the second opening 3, and running through the through-hole 1A from one first opening 2 to the other second opening 3; second wiring 21 having one end connected to the other end of the first wiring 11 and the other end 82 drawn out from the first opening 2 as a filter output end, and running through the through-hole 1A from the second opening 3 to the first opening 2; a first capacitor 41 provided between the ground and a connecting portion 31 of the first wiring 11 and the second wiring 21; and the second capacitor 51 provided between the other end 82 of the second wiring 21 and the ground.

An insulated power supply apparatus includes, a transformer; a switching element connected in series with a primary side winding of the transformer; an active clamp circuit connected between terminals of the primary side winding of the transformer; and a power supply control semiconductor device. The switching element includes a field effect transistor and a current-voltage conversion element is connected between a source terminal of the switching element and a grounding point. The power supply control semiconductor device includes the following, a first external terminal in which voltage according to a drain side of the switching element is input, a second external terminal in which voltage converted by the current-voltage conversion element is input, an on/off control circuit that performs turn-on and turn-off of the switching element, and a ZVS determining circuit that determines whether zero voltage switching control is performed.

A multiphase converter topology is used for the transmission of electrical energy from an AC voltage input with m grid phase connections to a DC voltage output or vice versa. It has a power part with half-bridges for switching currents, an AC voltage filter between the power part and the AC voltage input, and DC voltage block(s) connected between the power part and the DC output. The AC voltage filter has alternating voltage filter stage(s) with m+1 input connections, m+1 output connections and a ground connection. The m grid phase connections are thereby connected in parallel to one another and form a first phase connection for the connection of a single-phase AC voltage. A neutral conductor connection of the AC voltage filter forms a neutral conductor connection of the AC voltage input and a second phase connection for the connection of the single-phase AC voltage.

In a DC pulse power supply device according to the present invention, at the time of starting pulsing operation, the duty of the pulsing operation of a chopper circuit is controlled, a switching element is set to an ON state, and the pulse width at which the DC reactor is in an energized state is made variable over the period until the capacitor voltage is charged to a sufficient voltage to reset the magnetic saturation of the DC reactor. Gradually increasing the pulse width suppresses the degree of increase in the DC reactor current, and suppresses the DC reactor current below the magnetic saturazion level. As a result, the magnetic saturation of the DC reactor is suppressed at the time of starting pulsing operation.

A resonant core power supply includes a core with excitation, resonant, and load windings where the resonant winding is coupled to a tank circuit and a controller manipulates the phase, amplitude and waveform of an excitation signal applied to the excitation winding.

System and method for managing a cumulative DC offset in a magnetizable material. A primary driving AC voltage and a magnetic flux sensor. The flux sensor output is continuously received into memory while the the flux sensor output for each phase half-cycle is processed to continuously compute and re-compute in real time a flux-second integral for each half-cycle. The two half-cycle flux-second integrals are compared to each other for a DC offset value and the offset value drives a slow loop DC compensation circuit to steer a PWM control.