Dynamic UPS vs. Static UPS

Despite performing the same functions, static UPSs and dynamic UPSs deliver different performance to our DC and its features vary greatly, as do the components that make them up.
Dynamic or rotary UPSs are manufactured with higher capacities and higher voltage generation possibilities (with power ratings from 200kW to 3000kW) perfect for industrial environments. By installing parallel equipment, the dynamic can reach up to 40MW while the static reach up to 4-5MW. In dynamic UPSs, the batteries can be replaced by a kinetic storage system and they have an electric motor/generator that transforms electrical energy into mechanical and vice versa.

During its operation, dynamic UPSs store energy to be used in case of failure or cut, although to protect against supply cuts we must have a coupled diesel or gas engine. Having a single UPS unit and generator can be an advantage or disadvantage depending on the casuistry and project design purpose. Unifying can simplify the implementation although we must be aware that in case of failure we will be left without the two systems. There is also no possibility of adding an external Bypass to the UPS.

An important point to compare is efficiency. We speak of efficiencies of 95-97% of the dynamic versus 94-96% of the static ones. This difference increases when working at high load percentages (>50 %). In the case of Data Centers with A and B branch, the usual load is below 50%.

Static UPSs are the most widespread in the market and require a lower initial investment, since we can expand the equipment in a modular way, even working in parallel.

They need to have air conditioning systems, since its ideal working temperature ranges from 20º-25º.

In contrast, operating cost studies show that maintaining rotary UPS systems is more cost-effective.

But these solutions also have disadvantages on both sides. On the one hand, dynamic UPSs:

    • They imply a higher cost, use of space (for low autonomy) and are noisier.
    • They need auxiliary elements such as climate pumps, ventilation grilles, motors, etc.

The autonomy in case of diesel engine failure is less than 1 minute.

Static UPSs also have drawbacks:

  • They also need auxiliary elements: Climate, cleaning, batteries.
  • They are made up of a large number of elements which increases the chances of failure.
  • They support less short-circuit current than the dynamic.

The choice of the best UPS will depend on the power needs, on the investment capacity for the project and on the type of design that gives us greater security in each case. Dynamic UPSs are less likely to fail and are more energy efficient, although more expensive.

Static UPSs allow us to work with less initial investment and the possibility of tiered growth according to our needs and are more present in the market.
The Custom Innovation philosophy developed by GESAB allows to develop projects completely customized and adapted to the needs of the client, a tailored Data Center always looking for maximum availability.