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.

Create Function

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 PQ-buses in the power flow calculation, with an option to use the so-called 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:

\begin{align*} z_{const} =& const\_z\_percent / 100 \\ i_{const} =& const\_i\_percent / 100 \\ p_{const} =& (100 - const\_z\_percent - const\_i\_percent) / 100 \end{align*}

The load power values are then defines as:

\begin{align*} P_{load} =& p\_mw \cdot scaling \cdot (p_{const} + z_{const} \cdot V^2 + i_{const} \cdot V ) \\ Q_{load} =& q\_mvar \cdot scaling \cdot (p_{const} + z_{const} \cdot V^2 + i_{const} \cdot V) \end{align*}

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 \(Q_{load}\).