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Unbalanced Load Flow Software

Unbalanced Load Flow Analysis Software
Unbalanced Load Flow Diagram
A robust and efficient power flow solution method must be able to model special features of distribution systems with sufficient accuracy. With ETAP's Unbalanced Load Flow module, you can easily model your unbalanced system with detailed representation of component unsymmetrical characteristics. Accurate and reliable results are available describing your system’s unbalanced operating conditions. Automatic alarm / warning and advanced features such as automatic line constant calculation make it the most advanced Unbalanced Load Flow program available today.

Unbalanced Load Flow Analysis Software Key Features

  • Unbalanced power flow
  • 1-phase & unbalanced 3-phase modeling
  • Open-Delta transformer modeling
  • Center-tap transformer modeling
  • Unbalanced & nonlinear load modeling
  • Phase & sequence voltage, current, & power
  • Voltage & current unbalance factors
  • Transmission line coupling
  • Automatic device evaluation

Unbalanced Load Flow Analysis Software Capabilities

  • 1-phase, 2-phase (2W & 3W), 3-phase (3W & 4W)
  • Unbalanced loads & branches
  • Machine internal sequence impedances
  • Machine/transformer various grounding types
  • Modeling of transformer winding connections
  • Modeling of open-delta and center-tap transformer
  • Isolated sub-systems with voltage-control source modeling
  • Isolated single-phase source and system modeling
  • Transmission line coupling between phases of one line & multiple lines
  • Loads of constant power, constant impedance & constant current
  • Generic load as function of voltage & frequency
  • Generator governors with isochronous or droop mode
  • Generator exciters with AVR or Mvar / PF control
  • Transformer load tap changers (LTC / regulators)
  • Phase-shifting transformers
  • Report voltage and power in multi-units

Flexible Operations

  • Diverse operating conditions
  • Multiple loading categories
  • Multiple generation categories
  • Multiple demand factors
  • Unlimited configurations
  • Different nameplate data
  • Global & individual bus diversity factors

Unique Features

  • Swing, voltage regulated, & unregulated power sources
  • Auto-adjust voltage regulator settings
  • Unlimited configurations
  • Diverse operating conditions
  • Multiple demand factors
  • Current-injection method
  • Five levels of automatic error checking
  • Save solution control parameters for each scenario
  • Make changes to your system & re-run studies instantly
  • Conduct unlimited “what if” studies within one database 10,000+ bus capability

Automatic Result Evaluation

  • User-defined alert / warning limits
  • Bus / transformer / cable / line / reactor overloading
  • Bus over / under voltage
  • Generator overload & over / under excitation
  • Voltage & current unbalance level
  • Abnormal negative & zero sequence voltage & current

Unbalanced Load Flow Analysis Report

Study Options

  • User-controlled convergence parameters
  • Multiple loading conditions
  • Multiple generation levels
  • Advanced solution techniques for fast convergence
  • Automatic parameter adjustment for temperature & tolerance
  • Global & individual bus diversity factors
  • Option to update initial conditions


  • Individual phase & sequence voltage, current, & power
  • Voltage drops, losses, power flows, power factor, voltage / current unbalance factors, etc.
  • Input data, detailed load flows, & summaries
  • State-of-the-art graphic display of results
  • Export reports to your favorite word processing program
  • Graphically display device evaluation results
  • Graphically display buses with marginal or critical under / over voltage
  • Export one-line diagrams including results to third party CAD systems
  • Alert view to display critical & marginal limit violations