Operation; System Overview; System Design - S&C PureWave Operation And Maintenance

Operation

System Overview

System Design

16 S&C Instruction Sheet 658-500
The PureWave CES shall function and operate as an intelligent distributed energy
storage system to help utilities meet their rapidly changing Smart Grid challenges. By
positioning discrete amounts of utility-controlled storage where needed throughout
their distribution system, the PureWave CES shall enable utilities to rapidly respond
to changing electricity-use patterns, integrate renewables, manage renewable resource
intermittency, manage peak loads including plug-in electric vehicle loads, and provide
reliable backup power within a fraction of a second for improved power quality. With
the PureWave CES system's ability to provide high-speed transfer from the grid to bat-
tery power, outages are often barely perceptible to customers.
The PureWave CES is rated at 25 kW/25 kVA. Each PureWave CES unit shall consist of
1) a power conversion system (PCS) suitable for outdoor installation on a user-
furnished concrete pad or the user-furnished box pad, and
2) an energy storage unit consisting of either a select 25-kWh or 50-kWh lithium-
ion battery pack suitable for subsurface installation underneath the PCS, in a
user-furnished concrete vault. The PureWave CES shall be connected to the 120/
240 VAC split-phase secondary of a 25-kVA outdoor utility distribution transformer
(supplied by others) at a frequency either 50 Hz or 60 Hz.
The PCS shall consist of an inverter area housing an AC circuit breaker, an inverter,
user-accessible AC termination area, user-accessible DC termination area, and user-
accessible controls area.
In normal operation, the PureWave CES shall operate in current-source mode, provid-
ing such functionality as voltage regulation, power factor correction, peak shaving, and
load following. If the utility power source is interrupted, the AC breaker in the unit shall
open, isolating and islanding the load from the utility source. The energy storage unit
and inverter shall then power the islanded load for up to either 1 hour with a 25-kWh
battery pack or 2 hours with a 50-kWh battery pack. The energy storage unit will sup-
port the load until utility service is resumed or the energy storage unit of the PureWave
CES is depleted. See Figure 6.
SOURCE
Source Line 1, 2
CT 1, 2
Normal Control
Power
Battery Source or
Hot Start input
PCS Enclosure
Battery Enclosure
Management
Figure 6. PureWave CES System one-line diagram.
Terminal Bay
Load Line 1, 2
CB 1
Line 1, 2 LD
F3
F4
Control
Power
Supply
CT 3, 4
CT 5, 6
AC
Inverter
DC
PCS
Control
F1
F2
F
Battery
System DC Contactor M
Battery
Surge
Arrester
Discharge
Jumper
25 kWh or 50 kWh
LOAD