GE Industrial Solutions IEMi - Manual (Page 5)

2 DESCRIPTION
Fig. 2-1 Functional diagram of a Parallel System RPA in IEMi Operation Mode
GE Digital Energy offers the IEMi - Intelligent Energy Management integrated option to optimize
energy cost while maintaining the highest possible reliability for Parallel Redundant Uninterruptible
Power Supply units (max 6).
For Parallel System installations, secured with Redundant Parallel Architecture ™ (RPA ™ ), IEMi Operation
Mode saves energy by dynamically utilizing the UPS units as needed to meet the required load without
compromising the power quality to the critical load.
The software will calculate the number of UPS units which are needed for load supply based on
following:
• Redundancy (N+1 or N+2)
• System Load • Rectifier status
• Inverter operating time • IEMi Operation Mode programming
Particularly, the UPS control logic determines the minimal set of UPSs required to maintain a reliable
supply to the critical load.
Then, an efficiency optimization algorithm determines the best UPS configuration in order to maintain
the running UPS in their highest efficiency operating region.
Energy losses are reduced by switching the inverter section of one or more units to a stand-by state.
The critical load is fed by the remaining units operating in double-conversion.
As load increases, other units are gradually switched on-line in order to maintain the required
redundancy level.
The IEMi - Intelligent Energy Management integrated option is only available on parallel installations.
It is clear that in order to enjoy the benefits of IEMi operation a system programmed for N+1
redundancy requires a parallel installation of at least three UPSs, while four UPSs are required for N+2
redundancy.
IEMi - Intelligent Energy Management integrated is an option, and it is available only if introduced at the
factory, or if introduced in field installations by a GE GLOBAL SERVICES FIELD ENGINEER.
Benefits of IEMi - Intelligent Energy Management integrated include:
• Higher efficiency (reduced losses) in low-load conditions (efficiency optimization)
• No compromise on power quality (double-conversion operation)
• No compromise on system reliability (redundant operation)
Modifications reserved Page 5/24
OPM_OPT_IEM_iXX_XXX_XGB_V010.doc User Manual IEMi - Intelligent Energy Management integrated