An AC drive system for a battery driven moped

A petrol driven moped is converted to an electric vehicle by replacing its petrol engine with a three-phase 1.5 hp, AC squirrel cage induction motor drive system. The motor voltage rating selected is 200 V to keep the DC boost voltage level to a reasonable value. The power source used is a high energy density, 24 V, 110 Ah, Ni-Zn battery. A modified indirect current controlled step-up chopper as well as a standard push-pull DC-DC boost power converter is studied for the boost scheme. A simple three-phase quasi-square wave inverter is designed along with suitable protection for driving the motor. Successful trial tests of the system have been conducted at the laboratory.