3-phase power sensor

Total instantaneous power of the three phases.

  • signal
  • 3-phase
  • Modelica Standard Library
  • 5 ports
Block3-phase power sensorKindthreePhasePowerSensorLibrary3-phase

Description

Measures the total instantaneous power of a three-phase circuit. The current path pc–nc goes in series; the voltage path pv–nv goes across the element.

Example

Three-phase loads A 10 V three-phase supply into a resistive star load, a series R–L star load, and a capacitor bank in delta.

10 V 50 HzStar supplyGround supplyStar (R)Ground (R)Star (R–L)Ground (R–L)PowerCurrents (R)R 10 ΩR 10 Ω (R–L)Currents (R–L)L 31.8 mHCurrents (C)C 100 µFDeltaPhase aPhase bPhase cv av bv cGround aGround bGround c
In Gradara, select a 3-phase power sensor block and press F1, then choose Open example. It opens as a new model in My models, ready to run.

Also in this example:Voltage sensorGround3-phase AC source3-phase resistor3-phase inductor3-phase capacitorStar pointDelta connectionPhase a tapPhase b tapPhase c tap3-phase current sensor

Ports

Outputs 1

  • Ppowersignal · W

    Total instantaneous power, in watts.

Conserving terminals 4

  • i+pc3-phase

    Current path input (phases a, b, c). Current enters here.

  • i−nc3-phase

    Current path output (phases a, b, c). Zero voltage drop from pc.

  • v+pv3-phase

    Voltage path positive plug (phases a, b, c). Draws no current.

  • v−nv3-phase

    Voltage path reference plug (phases a, b, c). Draws no current.

Equations

Modelica
power = Σ (pv.k.v − nv.k.v) · pc.k.i, summed over k = a, b, c

Implementation

Modelica Standard Library 4.1.0Modelica.Electrical.Polyphase.Sensors.PowerSensor
MSL documentation

Assumptions and limitations

  • Instantaneous power only; for average or reactive power, filter or process the output.

Tips

  • For power into a load: pc on the source side, nc to the load, pv to the load’s phases, nv to its star point or return.

See also

Select a block in Gradara and press F1 to open its page offline.