US 6,160,722 A · Uninterruptible power supplies with dual-sourcing capability and methods of operation thereof

Abstract

An uninterruptible power supply (UPS) includes an AC source port configured to connect to an AC power source, a DC source port configured to connect to a DC power source and a load port configured to connect to a load. A rectifier circuit is operative to selectively couple the AC source port to first and second voltage busses through a first inductance. An inverter circuit is operative to selectively couple the load port to the first and second voltage busses through a second inductance. A bidirectional DC source coupling circuit is operative to couple the DC source port to the first and second voltage busses to provide bidirectional power transfer therebetween, preferably such that a voltage at the DC source port is maintained in a substantially fixed proportion to first and second DC voltages at respective ones of the first and second voltage busses. In one embodiment, the bidirectional DC source coupling circuit includes a transformer having first and second inductively coupled windings, the first winding having first and second end taps and a center tap coupled to the neutral bus. A switching circuit is operative to selectively couple the first end tap of the first winding to the first and second voltage busses. A rectifying circuit couples the second end tap of the first winding to the first and second voltage busses. A bidirectional DC-AC converter circuit is coupled between the second winding and the DC source port. Related operating methods are also discussed.

Claims33

Dependent claims

An uninterruptible power supply (UPS), comprising:

an AC source port configured to connect to an AC power source;
a load port configured to connect to a load;
a rectifier circuit that selectively couples the AC source port to first and second voltage busses through a first inductance;
an inverter circuit that selectively couples the load port to the first and second voltage busses through a second inductance;
and
a bidirectional DC source coupling circuit operative to couple a DC power source to the first and second voltage busses to provide bidirectional power transfer between the DC power source and the first and second voltage busses.

3 more elements

An uninterruptible power supply (UPS), comprising:

an AC source port configured to connect to an AC power source, the AC source port including a phase bus and a neutral bus;
a DC source port configured to connect to a DC power source;
a load port configured to connect to a load, the load port including a load bus and the neutral bus;
first and second voltage busses;
a first switching circuit that selectively couples the phase bus to the first and second voltage busses through a first inductance;
a second switching circuit that selectively couples the load bus to the first and second voltage busses through a second inductance;
a transformer including first and second inductively coupled windings, the first winding including a center tap coupled to the neutral bus;
a third switching circuit that selectively couples the first and second voltage busses to a first end tap of the first winding;
a rectifying circuit that rectifyingly couples a second end tap of the first winding to the first and second voltage busses;
and
a DC-AC converter circuit that selectively couples the DC source port to the second winding.

8 more elements

Dependencies are inferred from the claim text.

Uninterruptible power supplies with dual-sourcing capability and methods of operation thereof

Life of this patent

Uninterruptible power supplies with dual-sourcing capability and methods of operation thereof

Life of this patent

Abstract

Claims33