CEE Relays Ltd.

87C Whitby Road, Slough, SL1 3DR

Telephone: +44 1753 576477        Fax: +44 1753 825661

Website: www.ceerelays.co.uk

Unbalanced/Single-Phase Study Module

PTW Unbalanced Studies simulates systems with single-phase, two-phase and unbalanced three-phase load conditions. Phase and sequence currents can be displayed for different operating and load conditions including open-phase and simultaneous faults. Studies include demand load analysis, sizing, load flow/voltage drop and short circuit. Reports also include three-phase and single-phase panel schedules. Modelling includes single-phase, two-phase and three-phase lines, transformers, loads, and capacitors as well as single-phase mid-tap transformers.

Benefits:

	Design better systems where single-phase distribution and unbalanced conditions may exist.
	Identify undersized circuits caused by unbalanced loads before problems occur.
	Set negative sequence relays based on unbalanced fault and load simulations to identify problems that would otherwise go undetected until damage occurs.
	Communicate designs more easily with professional reports and graphs.
	Evaluate alternatives quickly and easily to establish an optimal design.

Interface Options:

	Display phase or sequence values with magnitude only, magnitude and angle, magnitude and power factor, or real and imaginary.
	Display individual phase values, maximum phase, or phase summation.
	Represent any combination of 1-phase, 2-phase and 3-phase systems including systems with mid-tap transformers.
	Shares common interface with balanced DAPPER studies, harmonic analysis, transient stability, equipment evaluation, reliability, and CAPTOR protective coordination modules.

Analysis Options:

	Connected, demand and design load analysis for each phase.
	Cable and transformer sizing based on design load of largest phase.
	Load flow and voltage drop through each 1-phase, 2-phase, and 3-phase branch.
	Representation of transformer automatic on-load tap-change (OLTC) options.
	Representation of mid-tap transformers.
	Representation of transformer no-load losses.
	Short circuit calculations including individual or simultaneous faults at different locations and on any phase combinations.
	Optional capacitance to earth representation.
	Unbalanced load representation in three-phase and single-phase panels and sub-feeds.
	Cable parameter calculator.
	Sequence to Phase and Phase to Sequence impedance conversions.
	Transmission line parameter calculator including multiple circuits, bundling, transposition, and line sag effects.

Typical Applications:

	City distribution systems with three-phase and single-phase feeds.
	Rural utility distribution systems with three-phase and single-phase feeds.
	Campus distribution systems.
	Industrial plants to identify normal and abnormal unbalanced conditions.
	Commercial and institutional buildings with three-phase and single-phase loads and panels.
	Setting negative sequence relays to detect abnormal unbalanced conditions.

Download the brochure in PDF format:

      Unbalanced.pdf (42kB)

Download Acrobat Reader - version 5.0 (or above) required.