Multi‐coil electromagnets: An accurate magnetic equivalent circuit, cost, and energy management

Abstract

Using nonintegrated multiple coils in an electromagnet is a way to manage energy and reduce maintenance costs. In order to model and analyze the lifting force and the magnetic field in different zone of the electromagnet, an exact magnetic equivalent circuit (MEC) is required. In this paper, an accurate MEC to analyze dual‐coil electromagnets is presented. MATLAB and ANSYS MAXWELL software are used to analyze the proposed MEC and simulate the magnetic field and the lifting force, respectively. In multi‐coil electromagnets, if a coil burns out, the electromagnet will still be able to lift the loads with a percentage of the nominal load weight. Also, it is only necessary to replace the burned coil, which reduces the maintenance costs of the electromagnet. Flexibility in winding excitation is another advantage of using multiple coils in electromagnets. In this case, one or more coils can be excited according to the weight of the load. This feature not only increases the lifetime of the coils but also reduces the energy consumption of the electromagnet and no need to use expensive power electronic converters to continuously control the current of coils. To evaluate the proposed MEC, the laboratory platform of an electromagnet was made to lift a load of 100 kg in the air gap of 2 mm and tested in two modes, single‐coil and dual‐coil. The analytical, simulation, and experimental results have very good agreement, indicating the high accuracy of the proposed MEC.

Cylindrical Electromagnets: An Accurate Magnetic Equivalent Circuit

“…Leakage permeances introduce flux leakage paths in the electromagnet. Flux leakage in the electromagnet can be modeled into three groups: horizontal leakage, vertical leakage, and end (or face) leakage [11][12][13].…”

“…This section deals with how to extract the permeance relationships used in the cylindrical electromagnet MEC. In order to avoid duplicate content, those interested can read additional explanations from references [11][12][13].…”

Electromagnetic force investigation of electromagnets with variable pole area in an electromagnetic diaphragm pump

“…Numerous researchers have suggested various methods to investigate and ameliorate the displacement-force characteristics of electromagnets [10][11][12]. S Wang and GY Xiong [13] constructed a non-working air gap between yoke and armature, and then connected it with the main working air gap in series.…”