ABSTRACT:-This study deals with varying the speed of BLDC motor by using zeta convertor. The three phase input to BLDC motor is given by three phase inverter working in 120⁰ mode of conduction. The zeta convertor is used to vary the input DC voltage to three phase inverter hence output voltage of three phase inverter also varies which varies the speed of BLDC motor. The output voltage of zeta is varied by varying the duty cycle of zeta by using dspic30f. Design of zeta convertor is done such that it operates in discontinuous inductor current mode.