Parallel UPS Systems: Enhancing Capacity and Redundancy

Understanding Parallel UPS Systems

Paralleling involves electrically and mechanically connecting two or more UPS modules to function as a unified system, providing a single output for either increased capacity or redundancy. In an N+1 redundant configuration, the system includes at least one more UPS module than is necessary to support the current load, ensuring that if one module fails, another can seamlessly take over without disrupting protected loads.

Eaton's patented HotSync paralleling technology is presented as a superior alternative to traditional methods. It eliminates system-level single points of failure through a peer-to-peer control strategy, where each UPS module operates independently without reliance on an external primary controller or complex inter-module wiring.

Key Challenges and Eaton's Solutions

The document outlines four primary challenges in parallel UPS systems:

• Control: Managing how UPSs cooperate as a unified system.
• Synchronization: Aligning the output of individual UPSs to a shared output.
• Load Balancing: Distributing the load equally among all paralleled UPSs.
• Selective Tripping: Identifying and isolating a malfunctioning UPS module.

Eaton's HotSync technology addresses these challenges by offering:

• Autonomous Control: A peer-to-peer system where each UPS assesses its own parameters, removing the vulnerability of primary-secondary control arrangements.
• Intrinsic Synchronization: UPSs synchronize to a common bypass source or their own output, eliminating reliance on external synchronization signals.
• Advanced Load Balancing: Internal software algorithms maintain load balance without inter-module communication, ensuring stable operation even under adverse conditions.
• Rapid Selective Tripping: Each module self-monitors and can isolate itself within microseconds of detecting a fault, preventing system-wide bypass.

Benefits of Paralleling

Paralleling offers significant advantages for both capacity expansion and redundancy. It allows organizations to scale their power infrastructure incrementally, matching growth without overbuilding and improving system efficiency. Eaton's UPS models, including the Eaton 9155, BladeUPS, 9355, Power Xpert 9395, and 93PM, are designed to support paralleling for these purposes.

For more detailed information on power management solutions and Eaton's commitment to reliable power, visit Eaton.com.