24
S&C Instruction Sheet 659-520
Operation
System Design
The PureWave SMS-250 is a storage-management system that can be connected to
380 Vac directly (or to 400, 415, or 480 Vac using an auto transformer), 50/60 Hz three-
phase utility feeder.
The storage-management system consists of a 263-kW/263-kVA PCS housed in a weath-
erproof enclosure suitable for outdoor or indoor mounting on a concrete or equivalent
pad applied with a user-furnished 618- to 850-Vdc, lithium-ion battery pack.
The PCS can use a modular design capable of parallel operation to achieve a rating
of up to 526 kW/526 kVA.
System Operation
The PCS converts ac power to dc power to charge the energy storage system (bat-
teries). The PureWave SMS-250 system is capable of performing several customizable
functions through a SCADA interface or the Human Machine Interface (HMI) computer.
Discharging of the battery into the electrical system is controlled by the power mode
selected. Table 1 describes the modes of system operation.
Table 1. Modes of Operation for the PureWave SMS-250 System
Modes
Description
Commanded Control
Enables the user to command real or reactive power to the load
Frequency Regulation Regulates frequency to close to the nominal frequency value to avoid
potential load equipment malfunctioning
Islanding
Fully supports the load using battery power when the utility source is not
available
Peak Shaving
Enables the system to absorb real power during off-peak times and to
supply real power during peak demand times
Power Scheduling
Dispatches power at a given time for a certain duration on any day of the
week
Renewable Smoothing Limits the rate of change in power from the renewable source by
charging/discharging the battery
Voltage Regulation
Mitigates voltage fluctuations by generating leading/lagging reactive
power (vars)
States
Listed in Table 2 are the five operating states of the PureWave SMS-250 system. Depend-
ing on the alarm condition, the system can be in any of these states. The LCD inside the
unit door and in Human Machine Interface (HMI) computer can both inform the user of
the system's current state. Table 2 describes each state.
Table 2. Operating States of the PureWave SMS-250 System
States
Description
Ready
The inverter is ready to run . The ac circuit breaker is closed . If the battery
is available, the dc circuit breaker is also closed . The IGBTs are not
switching .
Utility Connected Run
The inverter is running . The ac circuit breaker is closed . If the battery
is available, the dc circuit breaker is also closed . For var output, the ac
circuit breaker is only required to be closed . For real power output, the
ac and dc circuit breakers are required to be closed .
Island Run
The utility feeder source is not available and the inverter is running,
powering the local load . The ac and the dc circuit breakers are closed .
Inhibit
A problem with the inverter is inhibiting the proper operation of the PCS .
The inverter will not operate until the alarm is cleared . The ac and dc
circuit breakers are closed .
Trip Offline
An alarm is active that requires the ac and dc circuit breakers to be open .
The inverter will not operate until the alarm is cleared .
