Wye-Connected Variable Load

Three-phase variable load wired in wye configuration


Passive Devices / Time Varying


The Wye-Connected Variable Load block models a three-phase variable load wired in a wye configuration. Each limb of the load contains a resistor. The block calculates the resistance required to draw the real power of the physical signal input P at the rated voltage that you specify. Therefore, the block can represent a real load.

To ensure that the resistance is always greater than zero, you specify the minimum real power that the load consumes. The minimum real power must be greater than zero.

Electrical Defining Equations

The resistance is defined by



  • R is the per-phase series resistance.

  • VRated is the RMS, rated line-line voltage.

  • P is the three-phase real power required.


Main Tab

Rated voltage

RMS, rated line-line voltage for the resistance equation. The default value is 24e3 V.

Minimum real power

Minimum real power that the three-phase load dissipates when supplied at the rated voltage. The value must be greater than 0. The default value is 1e3 W.


The block has the following ports:


Physical signal input port for real power


Expandable three-phase port


Electrical conserving port associated with the neutral phase

Introduced in R2014b

Was this topic helpful?