This document discusses stepper motor drivers and their components. It describes how stepper motor drivers provide voltage to energize the stator windings in a sequence determined by a sequencer. The sequencer activates transistor pairs to control the direction and number of steps taken by the motor. It also notes that the step size and direction of motion must be specified based on the motor specifications and number of steps required.

1. ICE 3015: CONTROL SYSTEM
COMPONENTS
Class 14: Stepper Motor Drivers
Dr. S. Meenatchisundaram
Email: meenasundar@gmail.com
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018

2. Driver circuit:
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018
• To provide necessary voltage for energisation of stator winding
• To maintain proper sequence of energisation.
• The supply to the stator winding is neither dc nor conventional ac.
• It is in the form of train of pulses generated by some form of pulse
generator.
• Before controlling the stepper motor the programmer should know
the number of steps required per unit time or per revolution.
• It will decide the step size required.
• It also depends on motor construction type and specifications.
• At the same time the direction of motion should be specified.

3. Block diagram:
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018

4. Sequencer:
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018

5. Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018

6. Sequencer:
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018
• Q1-Q2 → A1, A2 → A1 – N, A2 – S
• Q3-Q4 → A2, A1 → A1 – S, A2 – N
• Q5-Q6 → B1, B2 → B1 – N, B2 – S
• Q7-Q8 → B2, B1 → B1 – S, B2 – N

7. Logic Sequencer:
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018
Step 1 Step 2 Step 3 Step 4
Q1 – Q2 ON
Q3 – Q4
Q5 – Q6
Q7 – Q8 ON
ON
ON ON
ON

8. Step Angle Calculation:
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018

9. Driving Circuit:
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018

10. References:
• nptel.ac.in/courses/108105063/pdf/L-
32(SS)(IAC)%20((EE)NPTEL).pdf
Control System Components (ICE 3015)
Dr. S.Meenatchisundaram, MIT, Manipal, Aug – Nov 2018