Ward

See also

Unit Systems and Conventions

Create Function

pandapower.create.create_ward(net, bus, ps_mw, qs_mvar, pz_mw, qz_mvar, name=None, in_service=get_default_value('ward', 'in_service'), index=None, **kwargs)

Creates a ward equivalent.

A ward equivalent is a combination of an impedance load and a PQ load.

Parameters:

• net (pandapowerNet) – The pandapower net within the element should be created

• bus (int | integer) – bus of the ward equivalent

• ps_mw (float) – active power of the PQ load

• qs_mvar (float) – reactive power of the PQ load

• pz_mw (float) – active power of the impedance load in MW at 1.pu voltage

• qz_mvar (float) – reactive power of the impedance load in MVar at 1.pu voltage

• name (str | None)

• in_service (bool)

• index (int | integer | None)

Returns:

the id of the created ward

Return type:

int | integer

pandapower.create.create_wards(net, buses, ps_mw, qs_mvar, pz_mw, qz_mvar, name=None, in_service=get_default_value('ward', 'in_service'), index=None, **kwargs)

Creates ward equivalents.

A ward equivalent is a combination of an impedance load and a PQ load.

Parameters:

• net (pandapowerNet) – The pandapower net within the element should be created

• buses (Sequence) – bus of the ward equivalent

• ps_mw (float | Iterable[float]) – active power of the PQ load

• qs_mvar (float | Iterable[float]) – reactive power of the PQ load

• pz_mw (float | Iterable[float]) – active power of the impedance load in MW at 1.pu voltage

• qz_mvar (float | Iterable[float]) – reactive power of the impedance load in MVar at 1.pu voltage

• name (Iterable[str] | None)

• in_service (bool | Iterable[bool])

• index (int | None)

Returns:

the ids of the created ward

Return type:

ndarray[tuple[Any, …], dtype[array]]

Table Structure

net.ward

Parameter	Datatype	Value Range	Explanation	nullable	required
name			name of the ward equivalent	✓
bus	int	>=0	index of connected bus		✓
ps_mw	float		constant active power demand [MW]		✓
qs_mvar	float		constant reactive power demand [MVar]		✓
pz_mw	float		constant impedance active power demand at 1.0 pu [MW]		✓
qz_mvar	float		constant impedance reactive power demand at 1.0 pu [MVar]		✓
in_service	bool		specifies if the ward equivalent is in service.		✓

Electric Model

The ward equivalent is a combination of a constant apparent power consumption and a constant impedance load. The constant apparent power is given by:

\begin{align*} P_{const} &= ps\_mw\\ Q_{const} &= qs\_mvar\\ \end{align*}

The shunt admittance part of the ward equivalent is calculated as described here:

\begin{align*} \underline{y}_{shunt} &= \frac{pz\_mw + j \cdot qz\_mvar}{S_{N}} \end{align*}

Result Table

net.res_ward

Parameter	Datatype	Explanation	nullable	required
p_mw	float	active power demand of the ward equivalent [MW]	✓	✓
q_mvar	float	reactive power demand of the ward equivalent [MVar]	✓	✓
vm_pu	float	voltage at the ward bus [p.u]	✓	✓

\begin{align*} vm\_pu &= v_{bus} \\ p\_mw &= P_{const} + Re(\frac{\underline{V}_{bus}^2}{\underline{Y}_{shunt}}) \\ q\_mvar &= Q_{const} + Im(\frac{\underline{V}_{bus}^2}{\underline{Y}_{shunt}}) \end{align*}