Storage

Note

Since storage power values are given in the consumer system, positive power models charging and negative power models discharging.

See also

Unit Systems and Conventions

Create Function

pandapower.create.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 dependent 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 dependent simulations by running several power flow calculations and updating variables manually.

Parameters:

• created (**net** - The net within this storage should be)

• **bus** (int)

• **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)

• **q_mvar** (float, default 0)

• **sn_mva** (float, default NaN)

• **soc_percent** (float, NaN)

• **min_e_mwh** (float, 0) - The minimum energy content of the storage (minimum charge level)

• **name** (string, default None)

• **index** (int, None)

• **scaling** (float, 1.)

• q_mvar. (Multiplies with p_mw and)

• **type** (string, None)

• **in_service** (boolean)

• **max_p_mw** (float, NaN)

• **min_p_mw** (float, NaN)

• **max_q_mvar** (float, NaN)

• **min_q_mvar** (float, NaN)

• **controllable** (bool, NaN)

• net (pandapowerNet)

• bus (int | integer)

• p_mw (float)

• max_e_mwh (float)

• q_mvar (float)

• sn_mva (float)

• soc_percent (float)

• min_e_mwh (float)

• name (str | None)

• index (int | integer | None)

• scaling (float)

• type (str | None)

• in_service (bool)

• max_p_mw (float)

• min_p_mw (float)

• max_q_mvar (float)

• min_q_mvar (float)

• controllable (bool | float)

Returns:

index (int) - The unique ID of the created storage

Return type:

int | integer

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 PQ-buses in the power flow calculation:

The PQ-Values are calculated from the parameter table values as:

\begin{align*} P_{storage} &= p\_mw \cdot scaling \\ Q_{storage} &= q\_mvar \cdot scaling \\ \end{align*}

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 pandapower. 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 \(Q_{storage}\).