Page 208 - Power Quality in Electrical Systems

190 Chapter Thirteen

■ Expansion: The questions are
■ Is expansion or modification of the load planned with or without
shutdown?
■ Is expansion of the standby power system planned in terms of
increased UPS-kVA rating, energy-storage capacity (batteries) or
engine-generator kVA?
■ Personnel: The questions are
■ What type of monitoring system is planned? Onsite, contract-type,
alarm equipment?
■ What level of training will be given to personnel? Instruction regard-
ing the complexity of the system? Will the training be done by vendors?
■ Cost: The questions are
■ How much are measures worth for a standby power system over the
basic unprotected supply of power to the load?

Components to Assemble Standby
Power Systems
Components have been described in the previous chapters to correct for
utility and internal-plant power deficiencies. These components can be
assembled into standby power systems for critical loads and systems.
They include the following [13.1]:
■ Transformers:
■ Constant-voltage (CV) transformers for voltage regulation
■ Phase-shifting transformers for harmonic cancellation
■ Power distribution unit (PDU) transformers to supply individual
loads
■ Dynamic Voltage Compensators:
■ Compensation for short-time voltage sag and interruption
■ Extended time operation
■ Single-phase, three-phase loads
■ Uninterruptible Power Supplies (UPSs):
■ Single-phase, battery support
■ Three-phase, battery support
■ Flywheel energy storage
■ Fuel-cell energy storage
■ Support Equipment:
■ Engine-generator set
■ Gas-turbine generator set
■ Transfer switch, E/G set
■ Transfer switch, utility feeders