239 results about "Snubber capacitor" patented technology

A switching power supply device includes a full-bridge circuit, a transformer, a rectifier circuit, a filter circuit, a first series connection of a snubber capacitor and a first diode, and a second diode. The full-bridge circuit includes switching elements which are controlled to be driven under phase-shift control. The first series connection is connected in parallel with the smoothing reactor, where one terminal is connected to a terminal on positive side of the rectifier circuit, and the other terminal is connected to an anode of the first diode. A cathode of the first diode is connected to one terminal of the smoothing capacitor which is applied with positive voltage. The second diode is provided between a terminal on negative side of the rectifier circuit and a connecting point of the snubber capacitor and the first diode. A cathode of the second diode is connected to the connecting point.

A switching power source apparatus can reduce the size of a transformer and realize the zero-voltage switching of a switch. The apparatus is compact, highly efficient, and low in noise. The apparatus has a series circuit connected to each end of a DC power source (Vdc1) and including a primary winding (5a) of a transformer (T) and a main switch (Q1), a rectifying-smoothing circuit to rectify and smooth a voltage that is outputted from a secondary winding (5b) when the main switch (Q1) is turned on, a series circuit connected to each end of the primary winding (5a) and including an auxiliary switch (Q2) and a clamp capacitor (C1), a series circuit connected to each end of the main switch (Q1) and including a diode (Dx1) and a snubber capacitor (Cx), a series circuit connected to a node between the diode (Dx1) and the snubber capacitor (Cx) and a node between the auxiliary switch (Q2) and the clamp capacitor (C1) and including an auxiliary winding (5x) and a diode (Dx2), and a control circuit (10) to alternately turn on/off the main switch (Q1) and auxiliary switch (Q2). When the main switch (Q1) is turned on, the snubber capacitor (Cx) is discharged through the auxiliary winding (5x) to the clamp capacitor (C1). When the main switch (Q1) is turned off, the snubber capacitor (Cx) is charged, to relax the inclination of a voltage increase of the main switch (Q1).

The subject matter of the invention is an inverter (3), more specifically for use in a photovoltaic plant (1) with a direct voltage input (connection terminals 4; 5) for connection to a generator (2) and an alternating voltage output (connection terminals 7; 8) for feeding into an energy supply network (6) as well as with a DC-AC converter (12) with semiconductor switch elements (15) and an intermediate circuit (11), at least one short-circuit switch element (18) being connected in parallel to the generator (2), so that the voltage will not exceed a maximum voltage value neither at the connection terminals (4; 5) of the generator (2) nor between the connection terminals (9; 10) of the inverter. This is achieved in that the inverter (3) comprises, in the intermediate circuit (12), a buffer capacitor (14) that is connected to the generator (2) through a protection diode (17) so that said buffer capacitor (14) will not be discharged upon actuation of the short-circuit switch element (18), the generator (2) working according to a clock rate in the short-circuit mode of operation.

In a semiconductor module according to certain aspects the invention, a U-terminal and an M-terminal overlap each other in a manner to reduce inductance and to further to reduce the size of snubber capacitor. In certain aspects of the invention, a P-terminal, M-terminal, N-terminal, and U-terminal are arranged such that the U-terminal, through which currents flow in and out, is arranged farthest away from control electrodes to reduce the noises superposed to control electrodes, and the P-terminal, M-terminal, N-terminal, and U-terminal are aligned to facilitate attaching external connection bars thereto. A power semiconductor module according to aspects of the invention can facilitate reducing the wiring inductance inside and outside the module, reducing the electromagnetic noises introduced into the control terminals, and attaching the external wirings to the terminals thereof simply and easily.

A frequency converter includes an intermediate circuit without any capacitors and an electronics which is supplied with power from a power supply device. The power supply device has a buffer capacitor which is disposed on an input side of the power supply device and connected electrically in parallel with the intermediate circuit. Connected to the buffer capacitor is a supply line in which a decoupling diode is disposed. A semiconductor adapted to be switched off is connected electrically back-to-back in parallel with the decoupling diode and has a control output which is connected to an output of an identification device for recognizing a power-line failure.

An integrated circuit on a substrate comprises a buffer capacitor in a buffer region. The buffer capacitor comprises a buffer electrode arranged at least partially in a recess, and a dielectric layer disposed between the buffer electrode and the substrate.

Provided is a direct-current converter which can reduce power consumption at light load by reducing switching losses of a main switch. The direct-current converter is provided with: a first serial circuit which is connected to both ends of a direct current power supply Vdc1 and in which a primary winding P of a transformer T and a main switch Q1 are serially connected to each other; a second serial circuit which is connected both ends of the primary winding P of the transformer T and in which an auxiliary switch Q2 and a snubber capacitor C2 are serially connected to each other; rectifying/smoothing circuits D5, D6, L1 and C5 which rectify and smooth a voltage generated in a secondary winding S of the transformer T by energy supplied from the primary winding P of the transformer T when the main switch Q1 is turned on; and a control circuit 10 which turns on/off the main switch Q1 and the auxiliary switch Q2 alternately using a signal with predetermined switching frequency. The control circuit 10 reduces the switching frequency during light load.

A power converter including a main circuit and a sub-circuit. The main circuit serves as a step-up/down chopper circuit including a series-connected assembly of main switches, an inductor coupled to a joint of the main switches, and a capacitor connected in parallel to the series-connected assembly. The sub-circuit is designed to establish the soft-switching and includes a snubber capacitor, a first sub-switch coupled to the joint of the series-connected assembly and a negative terminal of the snubber capacitor, a second sub-switch coupled to the joint and a positive terminal of the snubber capacitor, a third sub-switch coupled to the positive terminal of the snubber capacitor and a high-potential terminal of the main circuit, and a fourth sub-switch coupled to the negative terminal of the snubber capacitor and a low-potential terminal of the main circuit.

Provided is a DC-DC converter capable of reducing not only a turn-off loss but also a turn-on loss. A snubber capacitor has one end connected to an anode of a step-up diode, a current input end of a step-up switching element and a main reactor. A first snubber diode has a cathode connected to other end of the snubber capacitor, and an anode connected to a cathode of the step-up diode. A second snubber diode has an anode connected to the cathode of the first snubber diode and other end of the snubber capacitor. A snubber reactor has one end connected to the anode of the first snubber diode, and other end connected to a cathode of the second snubber diode.

A drive system includes a central power supply with a line-commutated converter and a DC/DC converter connected downstream of the line-commutated converter, and a plurality of inverters, each inverter having an output connected a load, for example a motor, and a DC input connected to a regulated DC voltage output of the central power supply. Buffer capacitors are connected across the respective input and output of the DC/DC converter. The drive system further includes an energy recovery device with an input connected to the controlled voltage output of the central power supply and an output connected to at least two input terminals of the line-commutated converter. This type of drive system eliminates a bulky brake circuit.

A DC power supply including a resonant circuit on a secondary side of a transformer suppresses a surge voltage during power recovery of diodes constituting a rectifier circuit, correctly estimates a load current from a secondary current of the transformer, and adjusts supplied power when a load is light. The DC power supply includes a DC voltage source, a converter, a transformer, a rectifier circuit, a resonant circuit composed of a resonant switch and a resonant capacitor, a filter reactor, a filter capacitor, a snubber diode, a snubber capacitor, a load, first and second voltage sensors, a current sensor, and a controller for controlling gate pulses of semiconductor devices constituting a converter and the resonant switch and a signal for adjusting operation timings of A/D converters converting the signals of these sensors.

The invention a magnetoelectric induction heating device which comprises a harmonic oscillation loading circuit including subjects to be heated for converting direct current voltage into alternative current voltage to provide power to the oscillation loading circuit; and a power source circuit for generating direct current voltage. The inverter comprise at least two semi-conductor switch elements connected in series to form up-down branches; a buffer capacity switching unit for switching buffer capacity according to the material of objects to be heated, and a oscillation capacity switching unit for switching oscillating capacity according to the material of the objects to be heated.

The present disclosure relates to an LC snubber circuit for a switching converter, wherein the switching converter includes an inductor and a switching device connected in series. The LC snubber circuit can include a first snubber diode, a snubber capacitor, a second snubber diode, and a snubber transformer having a primary winding and a secondary winding. The secondary winding of the snubber transformer is connected to an output of the switching converter.

A hybrid inductive-capacitive charge pump provided with a driving stage that comprises a step-up converter and a buffer capacitor, and a cascade of charge pump stages; the first stage of the stage cascade is connected to a power supply and the last stage of the stage cascade is connected to an output of the charge pump circuit; the charge pump circuit comprises elements for activating alternately the charge pump stages, transferring charge from one stage of the cascade to the next stage of the cascade, each stage of the cascade of charge pumping stages comprising a pass transistor and a capacitor.

Disclosed is a power conversion device that does not generate ripples, including a control circuit that generates a switching signal at a timing capable of realizing soft switching. The first main switch (Q1) and the second main switch (Q2) connected in series are connected to the positive terminal of the DC power supply at the end of the first switch, and connected to the negative terminal of the DC power supply at the end of the second main switch. Diodes (D1, D2) are connected in parallel on each main switch to make it reverse biased relative to the DC power supply. On each main switch, the main switch buffer capacitors (C1, C2) are connected in parallel. The connection point of the circuit is connected to the load, and the output is generated by controlling the on and off of the main switch according to the switching signal from the control circuit. The first auxiliary resonant circuit composed of the first auxiliary switch and the second auxiliary switch (Q3, Q4, Q5, Q6) connected in series and the resonant inductor (L1) connected in series on the second auxiliary switch is connected to the positive terminal of the DC power supply Between its connection point and the two main switches, connect diodes to the first and second auxiliary switches so that they are reverse biased relative to the DC power supply. The control circuit takes the voltage signals from the voltage detection part representing the voltages at both ends of the main switch and the above-mentioned auxiliary switch as input, and supplies the first and second auxiliary switches with an on-signal as a switch signal before supplying the first main switch Turn on the signal.