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This paper is aimed at the sensrorless control of capacitor in single phase induction motors. This is done towards three objectives i.e. maximization of average torque, minimization of torque pulsations and optimization of torque. The objectives are achieved by first obtaining the average torque and pulsation torque in terms of a variable capacitance and motor speed. The objective functions are then defined mathematically. Later the appropriate capacitance is calculated in a wide range of motor speed according to each objective. The motor speed is estimated by three methods using electrical sensors. The estimated speed is used for the switching of a power electronic switch in parallel with a constant capacitor to provide an appropriate capacitance in each case. Extensive simulation results are presented to verify the effectiveness of the sensorless capacitor switching in achieving the torque control objectives.