This paper presents a multizonal integral proportional (IP) speed controller for a closed loop speed . .
controller of a separately excited .dc motor. The motor is fed from a dc power supply and $epic :
converter. Tbis converter offers boih step-up and step-down characteristics of the 'motor terminal
voltage. Ah@ performance is achieved with a simple contml circuit having only one switch
, (MOSFET) for the proposed system. The output voltage and current are smooth and free of
ripples. The converter operates in both open and closed loop speed control. A multizonal IP speed
controller is used to overcome the possibility of change in the system parameters. The proposed
modeling,and simulation of the system are performed using differential equations which describe
the systembehaviour ih the different operating conditions. The rnn up, transient and steady state
are presented. Speed control using.multiZona1 IP speed controller is given to satisfy the best
required response for the load disturbances. Also, the motor speed can follow the desired reference
speed smoothly in the Werent operating zones, The experimental results have ensured the
proposed controller robustness, simple, and powerful control application capabilities. The
experimental and simulation results of the converter for both open and closed loop speed control
system are verified and a good correlation between them was found