Skip to main content

Symmetrical Components Fortescue Transformation Calculator

Charles Fortescue demonstrated that any unbalanced set of 3-phase phasors can be decomposed into three balanced sets: positive, negative, and zero sequence.

Magnitude of Phase A phasor.

Phase angle of Phase A.

Magnitude of Phase B phasor.

Phase angle of Phase B.

Magnitude of Phase C phasor.

Phase angle of Phase C.

What Is the Symmetrical Components Fortescue Transformation Calculator?

Symmetrical components simplify asymmetric fault analysis (single line-to-ground, line-to-line) by decoupling coupled 3-phase networks into independent sequence networks.

How Does the Symmetrical Components Fortescue Transformation Calculator Work?

Positive sequence rotates with normal ABC phase order, negative sequence rotates ACB, and zero sequence consists of three in-phase components.

Symmetrical Components Fortescue Transformation Calculator Formula & Variables

The core mathematical equation utilized by this calculator is expressed as:

egin{bmatrix} I_0 \ I_1 \ I_2 end{bmatrix} = rac{1}{3} egin{bmatrix} 1 & 1 & 1 \ 1 & a & a^2 \ 1 & a^2 & a end{bmatrix} egin{bmatrix} I_a \ I_b \ I_c end{bmatrix}, quad a = e^{j 120^circ}

Fortescue symmetrical components matrix transformation for 3-phase AC systems.

How to Use the Symmetrical Components Fortescue Transformation Calculator

  1. Enter magnitude and angle for all three phases A, B, and C.

Step-by-Step Example Calculation

Unbalanced Feeder Phase Currents

Input Values:

magA:100
angADeg:0
magB:90
angBDeg:-115
magC:105
angCDeg:125
Worked Steps: Positive sequence I1 = 98.2, Negative sequence I2 = 6.4 (6.5% unbalance), Zero sequence I0 = 3.8.

Understanding Your Result

Displays positive, negative, and zero sequence magnitudes along with the unbalance ratio (I2/I1 * 100%).

Factors That Affect the Result

  • Asymmetric load distribution and line impedance imbalances.

When Should You Use This Calculator?

  • Protective relaying settings (ANSI 46 negative sequence overcurrent), transformer grounding studies, and motor derating.

Assumptions & Limitations

  • Assumes linear steady-state sinusoidal 3-phase network.

Frequently Asked Questions

Calculation Accuracy & Reference Note

Exact complex algebraic transformation.

Explore more tools and calculators in Math Calculators