May 28, 2014. The understanding of eddy current effects is critical to improving the performance of many emergent electrical equipment applications, including high efficiency electric motors, generators, and transformers. Cobham Technical Services has demonstrated that updates to its Opera-3d electromagnetics simulator now allow designers to model such transient effects accurately. This fidelity of simulation gives Opera users a means of exploring new design concepts and accurately predicting their impact—to bring new generations of highly optimized products to market, such as electric motors, generators, transformers, electromagnetic brakes, and clutches.
The finite-element analysis tools of Opera-3d have been designed to model transient phenomena in electromagnetic systems. Features such as hexahedral mesh elements provide the fine resolution needed for accurately simulating the complex fields that are generated in regions where eddy currents are induced, while mesh layering improves the accuracy of capturing skin-effect in regions subject to high levels of eddy currents.
Opera-3d software also incorporates an advanced time-transient solver, which employs a mix of fixed and adaptive time-stepping to ensure simulation accuracy of transient phenomena. The size of the step can be changed automatically during simulation to maintain the same level of accuracy throughout the simulation. At the start of simulation, when there are large initial transients, the solver uses short time-steps; then as the simulation progresses and the initial fast transients decrease, it progressively increases the step size until the transients have died down and the eddy currents are less significant, when it switches to a fixed duration step.
A case study discussing the importance of including eddy currents in electromagnetic analyses, which highlights the results of applying Opera-3d to the TEAM Problem 24 benchmark is available at: http://operaFEA.com/case-studies. Users can also download a full description of the modeling and analysis methods used for the benchmark.