Torque ripple calculation of universal motor supplied by triac converter

A universal motor is one of the most used electrical machines in small electrical instruments and home equipments because its speed is easily controlled by the control of supply voltage. The present paper shows analytical calculation of the torque ripple and current waveform of the motor by triac converter supply. The converter output voltage waveform is expressed by the Fourier series. The armature reaction of the motor is included in the calculation. The motor performance is computed, using the circuit parameters determined by measurements. Calculated waveforms are confirmed by the experimental results.