DMC490 Microgrid Controller Software Configuration Guide
26
State Of Charge
Maximum (kWh)
This setting is the maximum capacity of the storage device. It
specifies the maximum level of storage state of charge (SOC),
in kWh.
0 to 1,000,000
kWh
300 kWh
State Of Charge
Minimum (kWh)
Specify the minimum level of storage state of charge, in kWh.
Due to lifetime considerations, SOC cannot usually go below a
certain limit. This is referred to as maximum depth of
discharge (DOD). For example, for a 100kWh storage device
with 80% DOD, State Of Charge Minimum is set to 20 kWh.
0 to 1,000,000
kWh
50 kWh
Upper
Boundary Store
Device1 (kW)
Storage state of charge needs to be always above
State Of
Charge Minimum
and below
State Of Charge Maximum
.
However, a variety of practical complexities, such as storage
standby loss, delay in issuing the charging/discharging
commands, measurements errors, and startup or
environmental conditions, lead to the violation of these limits
and can render the real-time microgrid optimization problem
infeasible. Apart from the infeasibility of the optimization
problem, there is also a chance of an undesired phenomenon
occurring, which is frequent charging and discharging (cycling)
of storage devices. These undesired outcomes (that is,
infeasibility and cycling) are avoided in the DMC490 MGC by
having some pre and post processing units outside of the
optimization core to modify the commands issued by the
controller, such as storage stop/start, or to change some input
readings, such as SOC. This also requires defining some small
regions around
State Of Charge Maximum
and
State Of
Charge Minimum
.
Thus, two regions below
State Of Charge Maximum
, and two
regions on either side of
State Of Charge Minimum
are
defined as shown in the following figure. If SOC is located in
region E, no action is required; however, if SOC is within any of
four regions A to D, its measured value is appropriately
changed together with issuing some necessary
charging/discharging commands.
Upper Boundary Store Dev1 is the upper boundary of the
maximum acceptable charging level. Configure it to be within
a few percent of storage maximum capacity
State Of Charge
Minimum
, for example one to five percent (that is, 0.01 to
0.05).
Refer to Figure 14 for more details
0 to 1 kW
0 kW
Lower
Boundary Store
Device2 (kW)
This setting is the lower boundary of the maximum acceptable
charging level. Configure it to be within a few percent of
storage maximum capacity (
State Of Charge Minimum
), for
example one to five percent (that is, 0.01 to 0.05).
0 to 1 kW
0 kW
Lower
Boundary Store
Device1 (kW)
This setting is the upper boundary of the minimum acceptable
charging level. Configure it to be within a few percent of
storage minimum capacity (
State Of Charge Minimum
), for
example one to five percent (that is, 0.01 to 0.05).
0 to 1 kW
0 kW
Lower
Boundary Store
Device2 (kW)
This setting is the lower boundary of the minimum acceptable
charging level. Configure it to be within a few percent of
storage minimum capacity (
State Of Charge Minimum
), for
example one to five percent (that is, 0.01 to 0.05).
0 to 1 kW
0 kW
Summary of Contents for DMC490
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