1. Field of the Invention
This invention relates to power supplies and more particularly relates to a high voltage, high frequency redundant bus for connecting redundant power supplies.
2. Description of the Related Art
Many computer systems store data that is critical and must be highly available. To increase data availability, redundant data storage, redundant computers, redundant data paths, redundant communication paths, etc. are used. One critical aspect of increasing reliability and data availability is for computer systems to be powered from redundant power supplies connected to multiple sources.
The system 100 depicted in FIG. 1 is a typical way of connecting redundant power supplies 102, 104 to a computer system, such as a blade center. Power supply 1 102 receives power from a first power source 106 and power supply 2 104 receives power from a second power source 108. The power supplies 102, 104 are connected through a backplane 110 to an output bus 112. Typically the output bus 112 connects to servers, storage devices, etc. The backplane 110 typically facilitates easy connection of servers, storage devices, and other components in a blade center. A blade center can support many devices so the power supplies 102, 104 are relatively large. The backplane 110 connects to the first power supply 102 through connector J1 114, to the second power supply 104 through connector J2 116, and to other devices through connector J3 118.
A typical blade center power supply 102, 104 may be rated at 1200 W, but may be rated higher or lower. Often the output bus 112 is regulated to a low voltage, such as 12 volts (“V”), but may be regulated to other voltages. For example, in a power supply 102, 104, voltages of +24 v, +20 v, +12 v, +6 v, +5 v, +3.3 v, and −12 v are commonly provided. The power supplies 102, 104 may also have multiple output stages to provide more than one output voltage.
At an output voltage of 12 V, a power supply 102, 104 rated at 1200 watts (“W”) could supply 100 amperes (“A”). If the supplied voltage is lower, the rated amperage would be even higher. At 100 A, the buses or wires in the backplane 110 and output of the power supplies 102, 104 must be large. Connectors 114, 116, 118 rated for 100 A are large, complex, and expensive. The cost of the connectors 114, 116, 118 and wiring can drive up the cost of the computer system 100 and can increase complexity.