Equivalent Circuit Encompassing Electrical and Mechanical Parts of Direct Current Motors

In this paper, a novel equivalent circuit of DC motors, which encompasses both electrical and mechanical parts, is presented. This equivalent circuit, which is more compact than the previously reported and requires only passive elements, allows for simulations of circuits containing DC motors to be carried out using SPICE program. Simulation and experimental results are shown to be in good agreement with theoretical calculation. The concept of this new equivalent circuit contributes to the understanding of DC motor operation using basic electrical circuit analysis.