Load¶
Note
Loads should always have a positive p_mw value, since all power values are given in the consumer system. If you want to model constant generation, use a Static Generator (sgen element) instead of a negative load.
See also
Create Function¶
 pandapower.create_load(net, bus, p_mw, q_mvar=0, const_z_percent=0, const_i_percent=0, sn_mva=nan, name=None, scaling=1.0, index=None, in_service=True, type='wye', max_p_mw=nan, min_p_mw=nan, max_q_mvar=nan, min_q_mvar=nan, controllable=nan, **kwargs)¶
Adds one load in table net[“load”].
All loads are modelled in the consumer system, meaning load is positive and generation is negative active power. Please pay attention to the correct signing of the reactive power as well.
 INPUT:
net  The net within this load should be created
bus (int)  The bus id to which the load is connected
 OPTIONAL:
p_mw (float, default 0)  The active power of the load
postive value > load
negative value > generation
q_mvar (float, default 0)  The reactive power of the load
const_z_percent (float, default 0)  percentage of p_mw and q_mvar that will be associated to constant impedance load at rated voltage
const_i_percent (float, default 0)  percentage of p_mw and q_mvar that will be associated to constant current load at rated voltage
sn_mva (float, default None)  Nominal power of the load
name (string, default None)  The name for this load
scaling (float, default 1.)  An OPTIONAL scaling factor to be set customly. Multiplys with p_mw and q_mvar.
type (string, ‘wye’)  type variable to classify the load: wye/delta
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.
in_service (boolean)  True for in_service or False for out of service
max_p_mw (float, default NaN)  Maximum active power load  necessary for controllable loads in for OPF
min_p_mw (float, default NaN)  Minimum active power load  necessary for controllable loads in for OPF
max_q_mvar (float, default NaN)  Maximum reactive power load  necessary for controllable loads in for OPF
min_q_mvar (float, default NaN)  Minimum reactive power load  necessary for controllable loads in OPF
controllable (boolean, default NaN)  States, whether a load is controllable or not. Only respected for OPF; defaults to False if “controllable” column exists in DataFrame
 OUTPUT:
index (int)  The unique ID of the created element
 EXAMPLE:
create_load(net, bus=0, p_mw=10., q_mvar=2.)
 pandapower.create_load_from_cosphi(net, bus, sn_mva, cos_phi, mode, **kwargs)¶
Creates a load element from rated power and power factor cos(phi).
 INPUT:
net  The net within this static generator should be created
bus (int)  The bus id to which the load is connected
sn_mva (float)  rated power of the load
cos_phi (float)  power factor cos_phi
mode (str)  “underexcited” (Q absorption, decreases voltage) or “overexcited” (Q injection, increases voltage)
 OPTIONAL:
same as in create_load, keyword arguments are passed to the create_load function
 OUTPUT:
index (int)  The unique ID of the created load
Load elements are modeled from a consumer point of view. Active power will therefore always be positive, reactive power will be positive for underexcited behavior (Q absorption, decreases voltage) and negative for overexcited behavior (Q injection, increases voltage).
Input Parameters¶
net.load
Parameter 
Datatype 
Value Range 
Explanation 
name 
string 
name of the load 

bus * 
integer 
index of connected bus 

p_mw* 
float 
\(\geq 0\) 
active power of the load [MW] 
q_mvar* 
float 
reactive power of the load [MVar] 

const_z_percent* 
float 
\([0,100]\) 
percentage of p_mw and q_mvar that is associated to constant impedance load at rated voltage [\(\%\)] 
const_i_percent* 
float 
\([0,100]\) 
percentage of p_mw and q_mvar that is associated to constant current load at rated voltage [\(\%\)] 
sn_mva 
float 
\(>0\) 
rated power of the load [kVA] 
scaling * 
float 
\(\geq 0\) 
scaling factor for active and reactive power 
in_service* 
boolean 
True / False 
specifies if the load is in service. 
type* 
String 
wye/delta 
Connection Type of 3 Phase Load(Valid for three phase load flow only) 
controllable** 
bool 
States if load is controllable or not, load will not be used as a flexibilty if it is not controllable 

max_p_mw** 
float 
Maximum active power 

min_p_mw** 
float 
Minimum active power 

max_q_mvar** 
float 
Maximum reactive power 

min_q_mvar** 
float 
Minimum reactive power 
*necessary for executing a power flow calculation.
Note
The apparent power value sn_mva is provided as additional information for usage in controller or other applications based on panadapower. It is not considered in the power flow!
Electric Model¶
Loads are modelled as PQbuses in the power flow calculation, with an option to use the socalled ZIP load model, where a load is represented as a composition of constant power (P), constant current (I) and constant impedance (Z):
What part of the load is considered constant with constant power, constant current or constant impedance is defined as follows:
The load power values are then defines as:
Result Parameters¶
net.res_load
Parameter 
Datatype 
Explanation 
p_mw 
float 
resulting active power demand after scaling and after considering voltage dependence [MW] 
q_mvar 
float 
resulting reactive power demand after scaling and after considering voltage dependence [MVar] 
The power values in the net.res_load table are equivalent to \(P_{load}\) and \(Q_{load}\).