Patent classifications
H02M1/342
CYCLE-BY-CYCLE REVERSE CURRENT LIMITING IN ACF CONVERTERS
In an embodiment, a method for operating an ACF converter includes: turning on a low-side transistor that is coupled between a primary winding of a transformer and a reference terminal to cause a forward current to enter the primary winding, turning off the low-side transistor; after turning off the low-side transistor, turning on a high-side transistor that is coupled between the primary winding and a clamp capacitor to cause a reverse current to flow through the primary winding; and after turning on the high-side transistor, when an overcurrent of the reverse current is not detected, keeping the high-side transistor on for a first period of time, and turning off the high-side transistor after the first period of time, and when the overcurrent of the reverse current is detected, turning off the high-side transistor without keeping the high-side transistor on for the first period of time.
METHOD AND DEVICE FOR CONVERTING A VOLTAGE WITH SOFT SWITCHING OF THE SWITCHES
A method for converting an input voltage (V.sub.in) of a converter (1) into an output voltage (V.sub.out), the circuit comprising a first bridge arm consisting of two switches (A) and (B), a second bridge arm consisting of two switches (C) and (D), connected in parallel, a primary coil coupled to a secondary coil, and connected by a center point pole (PAB) of the first bridge arm, and by another center point pole (PCD) of the second bridge arm; the circuit further comprising a capacitor in parallel between the respective terminals of each of the switches (A, B, C, D); a third bridge arm formed by two switches (E) and (F), connected in series; each of the switches (A, B, C, D, E, F) being associated with a diode at the terminals of said switch; an injection inductance (L.sub.inj) connected to the center point (P.sub.AB) of the first bridge arm, and to the center point (P.sub.EF) of the third bridge arm; a monitoring-control unit configured to control the switches to turn them ON or OFF, according to a control cycle configured to ensure soft switching between ON and OFF.
DC VOLTAGE CONVERTER
The invention relates to a DC voltage converter for transferring power from a high voltage network to a low voltage network. As a result, a circuit configuration which can be operated alternatively as an active-clamp flyback converter or an active-clamp buck converter is used.
Controlled current manipulation for regenerative charging of gate capacitance
A regenerative gate charging circuit includes an inductor coupled to a gate of a FET. An output control circuit is coupled to a timing control circuit and a bridged inductor driver, which is coupled to the inductor. A sense circuit is coupled to the gate and to the timing control circuit, which receives a control signal, generates output control signals in accordance with a first timing profile, and transmits the output control signals to the output control circuit. In accordance with the first timing profile, the output control circuit holds switches or controllable current sources of the bridged inductor driver in an ON state for a first period and holds the switches or controllable current sources in an OFF state for a second period. Gate voltages are sampled during the second period and after the first period. The timing control circuit generates a second timing profile using the sampled voltages.
DUAL OUTPUT DC-DC BOOST CONVERTER WITH REDUCED OUTPUT LEAKAGE
A DC-DC boost converter includes an inductor coupled between an input voltage and an input node, a first path coupled between the input node and a first output node at which a first output voltage is generated, and a second path coupled between the input node and a second output node at which a second output voltage is generated. The DC-DC boost converter operates in a first operating phase where the first path boosts the first output voltage and where the second path is kept from boosting the second output voltage by the second path being coupled to the first path, and operates in a second operating phase where the second path boosts the second output voltage and where the first path is kept from boosting the first output voltage by the second path not being coupled to the first path.
Bridge leg circuit
A bridge leg switching a DC voltage to produce an AC voltage at its output terminal for supply to an inductive load. The bridge leg has first, second, third, and fourth switch assemblies, and at least a first inductive element. The first and second switch assemblies are serially connected between the bridge leg input terminals, the bridge leg output being formed at a point of interconnection of the first and second switch assemblies. The third and fourth switch assemblies are serially connected between the bridge leg input terminals, the inductive element being connected between a point of interconnection of the third and fourth switch assemblies and the bridge leg output. The third and fourth switch assemblies are controlled such that reverse current through either of the first or second switch assembly is reduced compared to bridge leg output current prior to the moment the bridge leg output is switched.
POWER CONVERTER AND CONTROLLER FOR A POWER CONVERTER AND MANNERS OF OPERATION THEREOF
A power supply comprises a controller configured to control a power converter by generating drive signals that control the opening and closing of a high side switch and a low side switch. The controller is configured to selectively control the high side switch according to various modes of operation depending on operating conditions such as input voltage and load power consumption. The modes of operation can include, for example, a mode in which the high side switch is closed and then opened once during each of the series of switching cycles and a mode of operation in which the high side switch is closed and then opened two times during each of the series of switching cycles.
ELECTRICAL ENERGY CONVERSION SYSTEM WITH PIEZOELECTRIC ASSEMBLY(S) AND ELECTRICAL TRANSFORMER
The electrical energy conversion system comprises: a converter including E first switching assembly or assemblies, each associated with an input voltage and including two first switches; N second switching assembly or assemblies, each associated with an output voltage and including two second switches; and at least one piezoelectric assembly connected to a switch; E>1, N>1; a control device configured for controlling, during a resonance cycle, a switching of the switches so as to alternate phases at constant voltage and phases at constant load across said piezoelectric assembly or assemblies.
The converter comprising an electrical transformer having a primary winding connected to a first switching assembly and a secondary winding connected to a second switching assembly, and each piezoelectric assembly being connected between a switch and a winding.
VARIABLE ACTIVE SNUBBER CIRCUIT TO INDUCE ZERO-VOLTAGE-SWITCHING IN A CURRENT-FED POWER CONVERTER
An electrosurgical generator includes: a power supply configured to output a direct current; a current source coupled to the power supply and configured to output source current based on the direct current, and a power converter coupled to the current source, the power converter including at least one power switching element operated at a switching waveform. The power converter is configured to generate a converted waveform based on the source current. The electrosurgical generator also includes a controller coupled to the power converter and configured to modulate the switching waveform and a snubber circuit coupled to the current source and the power converter. The snubber circuit is configured to return the voltage at the at least one power switching element to zero after the power converter generates at least a portion of the converted waveform.
INSULATED POWER SUPPLY APPARATUS
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.