Hybrid Network Model for PM Eddy Current Losses Considering Eddy Current Reaction Field and PWM Effects of PM Machine

This article proposes a hybrid network model for prediction of permanent magnet (PM) eddy current loss considering eddy current reaction field and pulsewidth modulation (PWM) effects of a PM machine. The key is to combine the 3-D eddy current reaction field with mesh-based magneto-electric coupling network model in rotor PMs dynamically. First, the electromagnetic inductions between the eddy current network and the equivalent magnetic network (EMN) are modeled. The appropriate meshing method is used both in the EMN and eddy current network for high accuracy and high matching degree. Second, the eddy current reaction fields are integrated with PM segments and bidirectional coupled with EMN transient magnetic fields. Then, effects of PWM are realized under nonsinusoidal supply in the hybrid network model to accurately predict the flow directions and density distributions. Different switching frequencies are analyzed for PM eddy current loss predictions. Finally, the effectiveness of the proposed hybrid model is verified by finite-element analyses and experimental results.