An Improved Equivalent Circuit Model of a Single-Sided Linear Induction Motor

Abstract

The derivation of the equivalent circuit for a single-sided linear induction motor (S LIM) is not straightforward, particularly if it includes longitudinal end effects from the cut-open primary magnetic path, transversal edge effects from the differing widths between the primary lamination and secondary sheet, and half filled primary slots. This paper proposes an improved series equivalent circuit for this machine. The longitudinal end effects are estimated using three different impedances representing the normal, forwards and backwards flux density waves in the air-gap, whose two boundary conditions are deduced by introducing the conception of magnetic barrier surface. The transversal edge effects are accounted by correction coefficient t K and an air-gap flux density correction coefficient b K. Using the series circuit, the performance of the S LIM was assessed in a similar manner to a rotating induction machine. A 4 kW S LIM prototype was tested which validated the simulation technique.

Secondary Back-Iron Saturation Effects on Thrust and Normal Force of Single-Sided Linear Induction Motor

“…Similar to rotary induction motors, the performance of SLIM can be investigated by equivalent circuit model [13][14][15][16][17]. For the design of the SLIM shown in Fig.…”

“…In design, the primary weight [5], the thrust and power to weight ratio [6], primary winding arrangement [7], [8], the power factor and efficiency [9][10][11] and thrust in constant current [12] have been considered. To study the performance of the SLIMS, several equivalent circuit models have been proposed which facilitate their analysis [13][14][15][16][17]. There are special phenomena in linear motors that make them different from their rotary counterparts.…”

A Modified Dynamic Model of Single-Sided Linear Induction Motors Considering Longitudinal and Transversal Effects

“…Dynamic and steady-state modeling of the LIM has been widely addressed in the literature. In this regard, the literature can be divided into four categories, including modified mechanical equation-based models (MMEMs) [4][5][6], winding function-based models (WFMs) [7][8][9], field theory-based models (FTMs) [10][11][12][13][14], and Duncan's approach based models (DAMs) [15][16][17][18][19][20].…”

“…In [11,12], the air-gap electromotive force (EMF) has been modified by a longitudinal end effect factor. An improved series equivalent circuit model based on field theory was presented in [13]. The secondary resistance and the magnetic inductance were modified by some coefficients to consider the longitudinal end effect and the transverse edge effect in [14].…”

Development of an Advanced Motor Control System for Electric Vehicles

“…Motor control system plays a very important role in driver safety and comfort. Induction motors (IMs) are widely used for electric vehicles due to their simple structure, good performance, and low cost [4,5,6]. As for the control methods for IM, there are the V/F control, field oriented control (FOC), direct torque control (DTC) and some modern control methods, like model predictive control (MPC), fuzzy control, and neural networks.…”