Extended Ward
See also
Create Function
- pandapower.create.create_xward(net, bus, ps_mw, qs_mvar, pz_mw, qz_mvar, r_ohm, x_ohm, vm_pu, in_service=True, name=None, index=None, slack_weight=0.0, **kwargs)
Creates an extended ward equivalent.
A ward equivalent is a combination of an impedance load, a PQ load and as voltage source with an internal impedance.
- INPUT:
net - The pandapower net within the impedance should be created
bus (int) - 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
r_ohm (float) - internal resistance of the voltage source
x_ohm (float) - internal reactance of the voltage source
vm_pu (float) - voltage magnitude at the additional PV-node
- slack_weight (float, default 1.0) - Contribution factor for distributed slack power
flow calculation (active power balancing)
- OUTPUT:
xward id
Input Parameters
net.xward
Parameter |
Datatype |
Value Range |
Explanation |
name |
string |
name of the extended ward equivalent |
|
bus* |
integer |
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] |
|
r_ohm* |
float |
\(>\) 0 |
internal resistance of the voltage source [ohm] |
x_ohm* |
float |
\(>\) 0 |
internal reactance of the voltage source [ohm] |
vm_pu* |
float |
\(>\) 0 |
voltage source set point [p.u] |
in_service* |
boolean |
True / False |
specifies if the extended ward equivalent is in service. |
*necessary for executing a power flow calculation.
Electric Model
The extended ward equivalent is a ward equivalent: with additional PV-node with an internal resistance.

The constant apparent power is given by:
The shunt admittance part of the extended ward equivalent is calculated as described here:
The internal resistance is defined as:
The internal voltage source is modelled as a PV-node (generator) with:
Result Parameters
net.res_xward
Parameter |
Datatype |
Explanation |
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] |