Centrifugal casting machines are a production machines used to produce ductile cast iron pipes in the casting method in El Nasr Casting Company . The Casting Machines were manufactured by Thyssen Rheinstahl Technik GmbH. They are usually driven by three-phase separately excited DC motor of a nominal voltage of 400V and nominal power 222 kW . Lower overall efficiency leads to higher electricity consumption [1].  Motor performance characteristics and control strategies are described for both AC and DC machines ,However, with advances in AC motor drives (vector flux variable frequency drives) their dynamic response has improved dramatically, making them an attractive alternative to DC drive systems. Due to improved dynamic response and better motor efficiency of AC drives (compared to DC drives), centrifugal casting machines using AC drives can run faster than using DC drives, resulting in improved productivity and significant electrical energy savings.