Industrial

Educational

Scientific

Sample problems

Examples gallery

Step-by-step tutorials

Verification examples

Programming examples

Distributive examples

Success stories

Customers

Split core current transformer

QuickField simulation example

Current transformer is used to measure the AC current. The input current is transformed to a measurable value.

Problem Type
Plane-parallel problem of AC magnetics.

Geometry
Model z-length is 10 mm.
Split core current transformer Current transformer is used to measure the AC current. The input current is transformed to a measurable value. Core Core AC current Winding V 60 mm 10 mm gap gap 10 mm 50 mm

Given
Input AC current is 100 A, frequency is f = 50 Hz.
Secondary winding number of turns is N= 122, conductor cross-section is Sc = 0.1964 mm², copper conductivity is σ = 58.5 MS/m.
Core permeability μ = 1000. There are 2 air-gaps at the core parts junction 0.1 mm each.

Task
Calculate the transformer's output voltage. The inner resistance of a voltmeter is 100 kOhm.

Solution
The winding is only partially represented in the 2D geometry model. Missing parts are represented by the resistor in the electric circuit.
Average turn length is 43.2 mm. The geometry model's winding sections have a total length of (10 mm + 10 mm).
The remaining part resistance is R_winding = (1 / σ) · N · (43.2 - 10 - 10) / Sc = 0.246 Ohm.
Transformer winding The winding is only partially represented in the 2D geometry model. Missing parts are represented by the resistor in the electric circuit. Core Winding 10 mm 10 mm 10 mm Represented by a resistor in a circuit Geometry model

Results
Output voltage is 1.3 V.
Split core current transformer