The present disclosure relates to a DC-to-DC converter. The DC-to-DC converter includes a first port coupled to a first full bridge and a transformer coupled to the first full bridge and to a second full bridge. The DC-to-DC converter further includes a second port coupled to the second full bridge; a first inductor coupled between the second full bridge and the second port; and a first freewheeling circuit including a first diode being coupled in series with a switch. The first freewheeling circuit is further coupled in parallel with the first inductor between the second full bridge and the second port. Thereby, the DC-to-DC converter has a wide input and wide output (WIWO) range and a voltage gain that is linear.

There is disclosed new topology for an Electronic Voltage Regulator (EVR) which can apply additive or subtractive (aka boost or buck) voltages to compensate for an increase or decrease in system voltages. This regulator employs a ladder of power capacitors which are in series and connected across the input voltage to apply different levels of voltages to a controlled or regulated transformer. Considering this, the proposed EVR can be utilized as a replacement for conventional electromechanical type on-load tap changers or (OLTCs) commonly used in power transformers, and meant to compensate voltage changes in a system. Electromechanical tap changers have some significant issues, such as defined time durations when switching to different taps, as determined by the spring-loaded mechanism's operation; a high malfunction rate due to mechanical switching when causing arcing, and thereby decreasing the operating lifetime of transformers. In this EVR instead of electromechanical taps, a combination of capacitors and TRIACs are used at each voltage level to eliminate arcing effects while increasing the speed of the tap changing process. Furthermore, the electronic regulator can improve the load power factor due to the presence of capacitors. Other advantages over conventional OLTC's is the elimination of a reactor, if used, and the elimination of a tap winding with its numerous tap leads and having correspondingly higher cost. This will reduce the overall size of the active part of the main transformers and improve efficiency by reducing operating losses. In addition, a new failure detection method is included that detects a failed TRIAC to enable the system to continue operating. The failure detection circuit is seamlessly incorporated within the main circuit and has a high-speed detection rate.

A power source apparatus including: a transformer including a primary coil, a secondary coil, and an auxiliary coil, and has a primary side and a secondary side which are insulated from each other; a rectifier circuit including a first output terminal and a second output terminal; a smoothing capacitor; a switching element; a first series circuit having a capacitor and a first rectification element connected in series; and a second series circuit having a second rectification element and the auxiliary coil connected in series. The number of turns of the auxiliary coil is smaller than the number of turns of the primary coil. A product a ratio between the number of turns of the auxiliary coil and the number of turns of the secondary coil and an output voltage on the secondary side of the transformer is equal to or lower than a voltage of the smoothing capacitor.

An on-board charger is provided with a bulk capacitor adapted to couple to a vehicle traction battery and a relay for receiving electrical power from an external power supply and to pre-charge the bulk capacitor. A power factor correction (PFC) circuit is connected between the bulk capacitor and the relay. The PFC circuit includes a switch that is adjustable between an on-position and an off-position. The switch enables current flow from the relay to the bulk capacitor in the off-position. A snubber circuit is coupled to the switch to damp a transient voltage present at the switch during a transition from the on-position to the off-position. A processor is programmed to control the switch.

A power conversion apparatus includes: a first stage on which a first module is mounted, a second stage stacked on the first stage and on which a second module is mounted, and a coolant circulation circuit allowing a coolant to circulate through the first and second modules. The coolant circulation circuit includes a first cooling pipe disposed on the first stage, a second cooling pipe disposed on the second stage, a first connecting member provided at an opening end of the first cooling pipe, a second connecting member provided at an opening end of the second cooling pipe, a connecting pipe connecting the first connecting member and the second connecting member, a first coupler that couples a first end portion of the connecting pipe to the first connecting member, and a second coupler that couples a second end portion of the connecting pipe to the second connecting member.

An isolated converter includes an input circuit, a transformer, a first switch, a second switch and a snubber circuit. The input circuit includes at least two input capacitors, and is configured to provide an input voltage. A divider node is arranged between the at least two input capacitors. The transformer includes a primary winding and a secondary winding to generate an output voltage on the secondary winding according to the input voltage. The primary winding of the transformer is electrically connected between the first switch and the second switch. The snubber circuit is electrically connected between the first switch and the second switch, and forms a discharge path with the primary winding. The snubber circuit is configured to receive a reflected voltage from the secondary winding back to the primary winding, and the divider node is connected to the discharge path.

An active-clamp flyback converter is provided with improved active-clamp switch control that switches on an active-clamp switch at an active-clamp switch on-time that equals a power switch on-time minus a peak charge time for an active-clamp capacitor. The peak charge time is the duration between the switching off of the power switch transistor and when the charging current through the active-clamp capacitor falls to zero. The controller measures this peak charge time following the switching off of the power switch transistor and then applies it to the subsequent switching on of the active-clamp switch so that the active-clamp switch is switched on at the power switch on-time minus the peak charge time.

This disclosure describes a non-dissipative snubber circuit configured to boost a voltage applied to a load after the load's impedance rises rapidly. The voltage boost can thereby cause more rapid current ramping after a decrease in power delivery to the load which results from the load impedance rise. In particular, the snubber can comprise a combination of a capacitive element, two inductive elements, and three switches, where a duty cycle of two of the three switches controls the voltage boost. The snubber can be arranged between a DC power supply and a switching circuit configured to generate a pulsed waveform for provision to the load.

A snubber apparatus includes N parallel charge paths, each of which has a positive-side capacitor, a first diode, and a negative-side capacitor sequentially connected in series between a positive-side terminal and a negative-side terminal, and that allows current to flow from the positive-side terminal's side to the negative-side terminal's side. The snubber apparatus includes N+1 parallel discharge paths, each of which has a second diode connected between the negative-side terminal or the negative-side capacitor in the k-th charge path of the N charge paths, and the positive-side capacitor in the (k+1)-th charge path of the N charge paths or the positive-side terminal, and that allows current to flow from the negative-side terminal's side to the positive-side terminal's side via at least one of the negative-side capacitor and the positive-side capacitor. At least one of the charge paths has a plurality of sections that are turned and adjacent to each other.

The present disclosure relates to a switching device including a RC snubber network. The present disclosure further relates to a RC snubber network for a switching device. A switching device is provided that includes a trench transistor and an RC snubber network connected in between a first terminal and a second terminal of the trench transistor. The RC snubber network includes at least one current concentrating segment that is configured to locally force a major part of the snubber current passing through the trench capacitors to flow through a reduced number of trench capacitors to thereby increase the Ohmic losses associated with the snubber current.