DC and AC uninterruptible power supply
First Claim
1. A power supply for providing alternating current (AC) and direct current (DC) to a plurality of loads, the power supply comprising:
- a transformer having first, second, third and fourth windings;
an AC input for receiving AC power from an external source, the AC input connected across the first winding through a backfeed relay;
an AC output connected across the first winding and connected to the AC input through the backfeed relay;
an inverter connected across the second winding;
a pair of battery terminals connected between the inverter and a center tap of the second winding;
a charger connected across the third winding, the charger coupled to the pair of battery terminals;
a rectifier connected across the fourth winding;
a DC output connected to the rectifier through a DC/DC regulator; and
, a controller coupled to the AC input, the backfeed relay, the inverter and the charger, wherein when AC power is received at the AC input the power supply operates in a normal mode wherein the controller closes the backfeed relay such that;
the AC output receives AC power from the AC input through the backfeed relay;
the rectifier receives AC power from the AC input through the backfeed relay and the transformer; and
, the DC output receives DC power from the rectifier through the DC/DC regulator, and when AC power is not received at the AC input the power supply operates in a backup mode wherein the controller opens the backfeed relay and causes the inverter to operate in push-pull fashion such that;
DC power received at the pair of battery terminals is converted to AC power and provided to the second winding through the inverter;
the AC output receives AC power through the transformer;
the rectifier receives AC power through the transformer; and
, the DC output receives DC power from the rectifier through the DC/DC regulator.
2 Assignments
0 Petitions
Accused Products
Abstract
A power supply for point-of-sale (POS) devices. The power supply comprises a transformer with first through fourth windings. An AC input is connected through a backfeed relay to the first winding. An AC output is also connected to the first winding. A battery and an inverter are connected to the second winding. A charger is connected to the third winding. A rectifier, DC/DC regulator and a DC output are connected to the fourth winding. When AC power is received at the AC input, the AC output and the transformer receive the AC power through the backfeed relay. The DC output receives DC power through the DC/DC regulator and the rectifier, which receives AC power through the transformer. When AC power is not received at the AC input, the battery and the inverter provide AC power to the transformer, and the AC output and the rectifier receive AC power from the transformer. The DC output receives DC power through the DC/DC regulator and the rectifier.
34 Citations
17 Claims
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1. A power supply for providing alternating current (AC) and direct current (DC) to a plurality of loads, the power supply comprising:
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a transformer having first, second, third and fourth windings;
an AC input for receiving AC power from an external source, the AC input connected across the first winding through a backfeed relay;
an AC output connected across the first winding and connected to the AC input through the backfeed relay;
an inverter connected across the second winding;
a pair of battery terminals connected between the inverter and a center tap of the second winding;
a charger connected across the third winding, the charger coupled to the pair of battery terminals;
a rectifier connected across the fourth winding;
a DC output connected to the rectifier through a DC/DC regulator; and
,a controller coupled to the AC input, the backfeed relay, the inverter and the charger, wherein when AC power is received at the AC input the power supply operates in a normal mode wherein the controller closes the backfeed relay such that;
the AC output receives AC power from the AC input through the backfeed relay;
the rectifier receives AC power from the AC input through the backfeed relay and the transformer; and
,the DC output receives DC power from the rectifier through the DC/DC regulator, and when AC power is not received at the AC input the power supply operates in a backup mode wherein the controller opens the backfeed relay and causes the inverter to operate in push-pull fashion such that;
DC power received at the pair of battery terminals is converted to AC power and provided to the second winding through the inverter;
the AC output receives AC power through the transformer;
the rectifier receives AC power through the transformer; and
,the DC output receives DC power from the rectifier through the DC/DC regulator. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
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Specification