Hold-up time extension for totem pole bridgeless power factor correction
AssigneeDell Products L.P.
InventorsDanny SC Wang, Rita Joy Fernandez Miranda, Alex Tsai, Eva Chao, Dennis Alinea Martin
Life of this patent
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Abstract
In one or more embodiments, a PSU comprises a bridgeless PFC circuit with a hold-up time extension. If a voltage drop is detected, a relay switches operation to a first boost converter action to store energy in a PFC choke. If voltage remains low, the PFC choke may transfer energy to a bulk capacitor, increasing the amount of time an information handling system can operate before a shut-down procedure needs to start. If power returns, selected switches are turned on in an order such that an inrush current does not damage components in the PSU.
Claims16
A hold-up time extension circuit for a power factor correction (PFC) circuit in a power supply unit (PSU) of an information processing system, the hold-up time extension circuit comprising:
- a relay between a power source and a PFC choke;
- a first branch connected to a first pole of the relay, the first branch comprising a hold-up capacitor;
- and
- a second branch connected to a second pole of the relay, the second branch comprising:
- a first sub-branch comprising a first switch and an inrush resistor between the first switch and the relay;
- and
- a second sub-branch comprising a second switch connected to the first branch between the inrush resistor and the relay,
- wherein in a first configuration associated with power received from the power source dropping below a first voltage level, the relay activates the first branch, wherein power from the hold-up capacitor energizes a bulk capacitor,
- wherein in a second configuration associated with receiving power from the power source, the relay activates the second branch to charge the hold-up capacitor.
A power factor correction (PFC) circuit in a power supply unit (PSU) of an information processing system, the PFC circuit comprising:
- a bulk capacitor;
- a PFC choke;
- a plurality of switches;
- and
- a hold-up time extension circuit comprising:
- a relay between a power source and the PFC choke, wherein in a first configuration associated with normal operation,
- a first branch connected to a first pole of the relay, the first branch comprising a hold-up capacitor;
- and
- a second branch connected to a second pole of the relay, the second branch comprising:
- a first sub-branch comprising a first switch and an inrush resistor between the first switch and the relay;
- and
- a second sub-branch comprising a second switch connected to the first branch between the inrush resistor and the relay,
- wherein in the first configuration associated with power received from the power source dropping below a first voltage level, the relay activates the first branch, wherein power from the hold-up capacitor energizes the bulk capacitor,
- wherein in a second configuration associated with receiving power from the power source, the relay activates the second branch to charge the hold-up capacitor.
A method of operating a power supply unit (PSU) comprising a first switch, a second switch, a third switch, a fourth switch, a bulk capacitor and a power factor correction (PFC) choke forming a PFC circuit, the method comprising:
- detecting an input voltage corresponding to at least a nominal voltage;
- and
- configuring a relay for normal operation, wherein a first node of the relay connects an electromagnetic interference (EMI) filter to the PFC choke;
- and wherein the first switch, the second switch, the third switch and the fourth switch are turned on and a fifth switch and a sixth switch associated with a hold-up circuit are turned off.
Dependencies are inferred from the claim text.