Storage battery system
View Patent ↗A storage battery system relating to the present invention includes N PCSes. Each of the N PCSes is connected to an individual storage battery module group. The storage battery module group is formed by connecting one or more storage battery modules in parallel. A maximum power storage capacity of the storage battery modules configuring at least one storage battery module group is different from a maximum power storage capacity of the storage battery modules configuring the other storage battery module groups. A controller determines charge/discharge amounts of the individual PCSes on the basis of a charge/discharge request from an EMS, the maximum power storage capacity of the storage battery module, the number of the storage battery modules and a storage battery capacity ratio.
1. A storage battery system for which N (N≥2) power conditioning systems are connected to a power system and a storage battery module group formed by connecting one or more storage battery modules in parallel is connected to each of the N power conditioning systems, and which is operated on a basis of a charge/discharge request from an energy management system that manages electric power supply/demand of the power system, the storage battery system comprising:
battery management units that monitor a state of the storage battery module group; and
a controller that receives the charge/discharge request and storage battery information supplied from the battery management units, and controls the N power conditioning systems on the basis of the charge/discharge request and the storage battery information, wherein the power conditioning system has a function of converting AC power of the power system to DC power and charging the DC power to the storage battery module group, and a function of converting the DC power of the storage battery module group to the AC power and discharging the AC power to the power system,
wherein a maximum power storage capacity of the storage battery modules configuring at least one storage battery module group is different from a maximum power storage capacity of the storage battery modules configuring the other storage battery module groups, and
wherein the controller includes a charge/discharge command unit that determines a charge/discharge amount of each of the N power conditioning systems so as to satisfy a relational expression (1) below:
[
Expression
1
]
P
i
=
Preq
×
Bnum
i
×
Cratio
i
∑
i
=
1
N
(
Bnum
i
×
Cratio
i
)
(
1
)
where,
P i is the charge/discharge amount of an i-th power conditioning system (1≤i≤N),
Preq is the charge/discharge request,
Bnum i is the number of the storage battery modules connected to the i-th power conditioning system, and
Cratio i is a capacity ratio of the maximum power storage capacity of the storage battery modules connected to the i-th power conditioning system to a reference power storage capacity.