Inverter (1-phase)

Single-phase two-level half-bridge inverter.

  • Boolean
  • electrical
  • Modelica Standard Library
  • 5 ports
  • 2 parameters
BlockInverter (1-phase)KindsinglePhaseInverterLibraryConverters

Description

A single-phase two-level inverter leg (half-bridge): an upper transistor from dc_p to ac and a lower transistor from ac to dc_n, each with an antiparallel freewheeling diode.

Example

H-bridge and single-phase inverter An H-bridge driving an RL load with 75 % duty, and an inverter leg making 50 Hz AC from a split supply.

Duty H 0.75PWM 10 kHz24 VGroundH-bridgeR 2 ΩL 10 mHi load12 V upper12 V lowerMidpointDuty 50 HzPWM 50 HzInverter legLoad 10 ΩGround (load)v ACGround (v AC)
In Gradara, select a Inverter (1-phase) block and press F1, then choose Open example. It opens as a new model in My models, ready to run.

Also in this example:DC voltageVoltage sensorCurrent sensorConstantGroundSine waveResistorInductorH-bridgePWM generator

Ports

Inputs 2

  • f+fire_pBoolean

    Upper transistor gate (Boolean). True connects ac to dc_p.

  • f−fire_nBoolean

    Lower transistor gate (Boolean). True connects ac to dc_n.

Conserving terminals 3

  • dc+dc_pelectrical

    DC bus positive terminal.

  • dc−dc_nelectrical

    DC bus negative terminal.

  • acelectrical

    AC output terminal (the leg midpoint).

Parameters

  • Transistor on resistanceRonTransistor0.00001 Ω

    ≥ 0

    On resistance of each transistor, in ohms. 0 or more.

  • Diode on resistanceRonDiode0.00001 Ω

    ≥ 0

    On resistance of each freewheeling diode, in ohms. 0 or more.

Equations

Modelica
fire_p true: ac.v ≈ dc_p.v; fire_n true: ac.v ≈ dc_n.v
Both false: the diodes set ac.v by the direction of the load current

Implementation

Modelica Standard Library 4.1.0Modelica.Electrical.PowerConverters.DCAC.SinglePhase2Level
MSL documentation

Assumptions and limitations

  • Ideal switches: transistors are GTO-type switches that conduct only forward, and diodes switch at 0 V. Off conductance is fixed at 10 µS and knee voltages at 0 V. No switching times, reverse recovery, or conduction voltage drop beyond the on resistance.
  • fire_p and fire_n both true shorts the DC bus; nothing prevents it and no dead time is inserted.

Tips

  • Drive fire_p from fire and fire_n from notFire of one PWM generator.
  • For an AC load, return it to a DC midpoint, such as the junction of two series capacitors or two sources.

See also

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