Transient Magnetic Analysis for Time-Domain Fields and Forces

Transient Magnetic Analysis in EMWORKS

Transient magnetic analysis in EMWORKS solves time-dependent magnetic fields from switching currents, motion, and nonlinear materials. It captures the evolution of flux, eddy currents, forces, and losses in CAD-based geometries.

• Time-domain fields from coils, windings, and busbars under arbitrary waveforms

• Motion of movers, rotors, armatures, plungers, and magnets

• Eddy currents and transient I²R/core losses

• Basis for force, torque, and coupled electro-thermal / motion studies

Key Features of EMWORKS' Transient Magnetic Analysis

• Time-domain magnetic fields: Solves transient magnetic fields for arbitrary current/voltage waveforms (step, PWM, surge, fault, etc.).

• Motion and moving parts: Supports motion of rotors, movers, armatures, plungers, and magnets with time-varying position.

• Nonlinear magnetic materials: Handles B–H curves and saturation in cores, yokes, and other ferromagnetic parts under transient excitation.

• Eddy currents and losses: Computes transient eddy currents and associated I²R/core losses in solid and laminated conductors.

• Coupling with circuits: Links coils/windings to external circuits for realistic drive conditions and switching transients.

• Forces and torque vs time/position: Calculates magnetic force and torque waveforms for actuators, relays, contactors, and electric machines.

• Data for multiphysics: Exports time-dependent loss distributions as heat sources for thermal and electro-mechanical studies.

Applications and Devices for Transient Magnetic Analysis

Typical use cases:

• Electric motors and generators – start-up, commutation, torque ripple, cogging torque, transient forces.

• Actuators, relays, contactors, solenoids – force vs time/position under step, PWM, or fault currents.

• Transformers and inductors – inrush current, core saturation, transient flux and losses.

• Power electronics – converters, inverters, choppers: switching transients, current ripple, stray inductance effects.

• Wireless charging and pulsed inductive systems – transient coupling, power transfer, and loss waveforms.

• Magnetic brakes, clutches, and dampers – time-dependent torque and heating during engagement.

• Magnetic bearings and levitation – dynamic stiffness, stability, and transient response to disturbances.

• Electromagnetic launchers and railguns – force, current, and flux evolution during pulse events.

Results of EMWORKS' Transient Magnetic Analysis

For each study (per time step), the Transient Magnetic module can report:

• Magnetic field H, Magnetic flux density B, Current density J, Eddy current distribution, Force density, Inductance matrix, Flux linkage, Impedance, Ohmic loss (I²R), Current, Voltage, Force, Torque, Stored magnetic energy

In coupled magneto-thermal analysis:

• Temperature, Temperature gradient, Heat flux