Storage
Note
Since storage power values are given in the consumer system, positive power models charging and negative power models discharging.
See also
Create Function
 pandapower.create_storage(net, bus, p_mw, max_e_mwh, q_mvar=0, sn_mva=nan, soc_percent=nan, min_e_mwh=0.0, name=None, index=None, scaling=1.0, type=None, in_service=True, max_p_mw=nan, min_p_mw=nan, max_q_mvar=nan, min_q_mvar=nan, controllable=nan, **kwargs)
Adds a storage to the network.
In order to simulate a storage system it is possible to use sgens or loads to model the discharging or charging state. The power of a storage can be positive or negative, so the use of either a sgen or a load is (per definition of the elements) not correct. To overcome this issue, a storage element can be created.
As pandapower is not a time dependend simulation tool and there is no time domain parameter in default power flow calculations, the state of charge (SOC) is not updated during any power flow calculation. The implementation of energy content related parameters in the storage element allows to create customized, time dependend simulations by running several power flow calculations and updating variables manually.
 INPUT:
net  The net within this storage should be created
bus (int)  The bus id to which the storage is connected
p_mw (float)  The momentary active power of the storage (positive for charging, negative for discharging)
max_e_mwh (float)  The maximum energy content of the storage (maximum charge level)
 OPTIONAL:
q_mvar (float, default 0)  The reactive power of the storage
sn_mva (float, default None)  Nominal power of the storage
soc_percent (float, NaN)  The state of charge of the storage
min_e_mwh (float, 0)  The minimum energy content of the storage (minimum charge level)
name (string, default None)  The name for this storage
index (int, None)  Force a specified ID if it is available. If None, the index one higher than the highest already existing index is selected.
scaling (float, 1.)  An OPTIONAL scaling factor to be set customly. Multiplys with p_mw and q_mvar.
type (string, None)  type variable to classify the storage
in_service (boolean)  True for in_service or False for out of service
max_p_mw (float, NaN)  Maximum active power injection  necessary for a controllable storage in OPF
min_p_mw (float, NaN)  Minimum active power injection  necessary for a controllable storage in OPF
max_q_mvar (float, NaN)  Maximum reactive power injection  necessary for a controllable storage in OPF
min_q_mvar (float, NaN)  Minimum reactive power injection  necessary for a controllable storage in OPF
controllable (bool, NaN)  Whether this storage is controllable by the optimal powerflow; defaults to False if “controllable” column exists in DataFrame
 OUTPUT:
index (int)  The unique ID of the created storage
 EXAMPLE:
create_storage(net, 1, p_mw = 30, max_e_mwh = 60, soc_percent = 1.0, min_e_mwh = 5)
Input Parameters
net.storage
Parameter 
Datatype 
Value Range 
Explanation 
name 
string 
Name of the storage unit 

bus* 
integer 
Index of connected bus 

p_mw* 
float 
\(\leq\) 0 
Momentary real power of the storage (positive for charging, negative for discharging) 
q_mvar* 
float 
Reactive power of the storage [MVar] 

sn_mva 
float 
\(>\) 0 
Nominal power ot the storage [MVA] 
scaling* 
float 
\(\geq\) 0 
Scaling factor for the active and reactive power 
max_e_mwh 
float 
The maximum energy content of the storage (maximum charge level) 

min_e_mwh 
float 
The minimum energy content of the storage (minimum charge level) 

max_p_mw** 
float 
Maximum active power 

min_p_mw** 
float 
Minimum active power 

soc_percent 
float 
0 \(\leq\) soc_percent \(\leq\) 100 
The state of charge of the storage 
max_q_mvar** 
float 
Maximum reactive power [MVar] 

min_q_mvar** 
float 
Minimum reactive power [MVar] 

controllable** 
bool 
States if sgen is controllable or not, sgen will not be used as a flexibilty if it is not controllable 

in_service* 
boolean 
True / False 
Specifies if the generator is in service 
*necessary for executing a power flow calculation
**optimal power flow parameter
Electric Model
Storages are modelled as PQbuses in the power flow calculation:
The PQValues are calculated from the parameter table values as:
Note
The apparent power value sn_mva, state of charge soc and storage capacity max_e_mwh are provided as additional information for usage in controller or other applications based on panadapower. It is not considered in the power flow!
Result Parameters
net.res_storage
Parameter 
Datatype 
Explanation 
p_mw 
float 
resulting active power after scaling [MW] 
q_mvar 
float 
resulting reactive power after scaling [MVar] 
The power values in the net.res_storage table are equivalent to \(P_{storage}\) and \(Q_{storage}\).