To date, data center design would employ one of two general design concepts: use of single, large kW generator sets with multiple busses, or multiple paralleled generators using traditional paralleling switchgear. With the advances in microprocessor technology, onboard generator controls, and software, most major manufacturers offer the ability to digitally parallel multiple generators without the need for traditional paralleling gear. This is what is referred to as an integrated paralleling system.
In the past, using traditional paralleling gear was the only way to tie multiple generators together to create N+1, N+2, 2N, or other system architecture types designed to increase system reliability. However, due to the high capital cost of traditional paralleling gear along with system complexity and a large physical footprint, these applications were limited to those who could justify the cost and design.