Hybrid simulation approaches for induction machine calculation

Abstract

Purpose Induction machines for traction applications are operated at working points of high ferromagnetic saturation. Depending on the working point, a broad spectrum of harmonic frequencies appears in the magnetic flux density of induction machines. Detailed loss analysis therefore requires local and temporal highly resolved nonlinear field computation. This loss analysis can be performed in the post processing of nonlinear transient finite element simulations of the magnetic circuit. However, it takes a large number of transient simulation time steps to build up the rotor flux of the machine. Design/methodology/approach In this paper, hybrid simulation approaches that couple static FEA, transient FEA and analytic formulations to significantly decrease the number of simulation time steps to calculate the magnetic field in steady state are discussed, analyzed and compared. Findings The proposed hybrid simulation approaches drastically decrease the simulation time by shortening the transient build-up of the rotor flux. Depending on the maximum error of the rotor flux linkage amplitude compared to the steady state value, a reduction of simulation time steps in the range of 55.5 to 98 per cent is found. Originality/value The presented hybrid simulation approaches allow efficient performing of the transient FE magnetic field simulations of induction machines operated as traction drives.

Multi-Stage Optimization of Induction Machines Using Methods for Model and Parameter Selection

“…For the computation of the T-FEM, an in-house state-of-the-art Finite Element (FE) solver called iMOOSE/pyMOOSE [47] is used. To reduce the computational effort of the T-FEM, a hybrid simulation approach presented in [48] is applied.…”

Approach for the Model and Parameter Selection for the Calculation of Induction Machines

“…This, in combination with the required transient time of the vector potential solution, leads to a high calculation effort of the transient Finite Element (FE) simulation. Faster transient is made possible by a hybrid approach via estimation of a starting solution from an open-circuit simulation [20].…”

Complete and accurate modular numerical computation scheme for multi‐coupled electric drive systems

“…In addition, the magnetic flux distribution is visualised [23]. In the case of the IM, this type of simulation is also used to extract the lumped parameter matrices that are necessary for the hybrid simulation scheme described in [24] and the next section. The demagnetisation test is used for permanent magnet (PM) machines.…”

“…In the linear and non-linear hybrid FEA, transient and static FE simulations are coupled with analytic models resulting in a hybrid simulation scheme. In [24] it is shown that those approaches reduce the simulation time of the IM, especially of the rotor flux development drastically. One requirement for this hybrid simulation scheme is the extraction of the lumped parameter matrices L and R describing the inductances and resistances described in [34].…”

“…FE simulation methods[24] Mesh of operating points with the calculated torque and fluxlinkage of an SM[3] IET Sci. Meas.…”