Obtaining maximum torque operation of single phase induction motor using simulation technique of MATLAB

Fractional KW electrical machines used in domestic and industrial applications are mostly asymmetrical two phase induction motor supplied by single phase supply. Though many techniques are available for control of three phase induction machine for extracting its best performance, but no such generalized technique is available for controlling Single Phase Induction Motor (SPIM). In this paper, a SPIM is studied, where a dynamic capacitor is used for obtaining maximum torque operation. The SPIM makes use of indirect current control of Voltage Source Inverter (VSI) with a capacitor on its DC bus, so that it can work as a variable capacitor. Then a maximum torque operation is obtained, by connecting this dynamic capacitor in series with the auxiliary winding, and is controlled in such a way to keep the main and auxiliary winding currents in phase quadrature to each other. And along with dynamic capacitor a dynamic model is developed in stator reference frame (d-q). For proposed configuration, performance of the SPIM is studied using MATLAB, to demonstrate the effectiveness of the dynamic capacitor.