Stepper Motor.ppt
- 2. Stepper Motor / Electro magnet
- 3. Rotor Stator Coils 2 1 S N 1 2 Outside Casing Stator Rotor Internal components of a Stepper Motor
- 4. 2 2 1 N S 1 S N Stators Rotor Cross Section of a Stepper Motor
- 5. Four Steps per revolution i.e. 90 deg. steps. Full Step Operation
- 6. Eight steps per. revolution i.e. 45 deg. steps. Half Step Operation
- 7. 2 2 1 1 S N S N N N S S 1 a b Winding number 1 2 a b Winding number 2 One step 6 pole rotor
- 8. How many steps are required for one complete revolution? Six pole rotor, two electro magnets.
- 9. The top electromagnet (1) is turned on, attracting the nearest teeth of a gear- shaped iron rotor. With the teeth aligned to electromagnet 1, they will be slightly offset from electromagnet 2 The top electromagnet (1) is turned off, and the right electromagnet (2) is energized, pulling the nearest teeth slightly to the right. This results in a rotation of 3.6° in this example. Practical Stepper motor operation
- 10. The bottom electromagnet (3) is energized; another 3.6° rotation occurs. The left electromagnet (4) is enabled, rotating again by 3.6°. When the top electromagnet (1) is again enabled, the teeth in the sprocket will have rotated by one tooth position; since there are 25 teeth, it will take 100 steps to make a full rotation in this example.
- 11. Stepping Motor to move read-write head Stepper motor applications
- 12. Paper feeder on printers CNC lathes Stepper motors Stepper motor applications
- 13. Rotor Stator coils CNC Stepping Motor
- 14. Advantages:- Low cost for control achieved Ruggedness Simplicity of construction Can operate in an open loop control system Low maintenance Less likely to stall or slip Will work in any environment Disadvantages:- Require a dedicated control circuit Use more current than D.C. motors High torque output achieved at low speeds Advantages / Disadvantages
- 15. Step 1 0 0 1 1 Step 2 1 0 1 0 Step 3 1 1 0 0 Step 4 0 1 0 1 + CW CCW Control sequence to turn a stepper motor
- 16. Servo Motor Detail + 5V Actuator Reduction gear Position feedback Potentiometer (closed loop system) Small electric DC motor