Permanent Magnet Stepper Motors

Introduction

There are two types of permanent magnet stepper motors. namely,  those are unipolar stepper and bipolar stepper. in unipolar stepper has center tap every windings it has at its stator.

Figure 1: Bipolar stepper

Figure 2: Unipolar stepper

There are two types of operation mode in stepper motors, those are known as full step and half step.

Control stepper motor

To rotate stepper motor in either direction, it has to be energized its windings sequentially. as mention about mode of operation has the different sequences, however half stepper mode has the intermediate state in between full step sequence.

1. Bipolar Stepper Motor controlling(sequencing phases for rotation )

Figure 3: Biploar stepper motor connection of stator windings

1.1 full step mode.

Figure 4: Bipolar stepper motor full step sequence.

	Clockwise				Anti-Clockwise
A	1	0	0	0	0	0	0	1
B	0	1	0	0	0	0	1	0
A_bar	0	0	1	0	0	1	0	0
B_bar	0	0	0	1	1	0	0	0

Table 1: bipolar stepper full step sequence

1.2 half step mode

.

Figure 5: Bipolar stepper motor half step sequence.

	Clockwise								Anti-Clockwise
A	1	1	0	0	0	0	0	1	0	0	0	0	0	1	1
B	0	1	1	1	0	0	0	0	0	0	0	1	1	1	0
A_bar	0	0	0	1	1	1	0	0	0	1	1	1	0	0	0
B_bar	0	0	0	0	0	1	1	1	1	1	0	0	0	0	0

Table 2: Bipolar stepper half step sequence

2 Unipolar stepper motor control.

Figure 6: Unipolar stepper motor wiring arrangement

2.1 full step mode for unipolar stepper motor.

	Clockwise				Anti-Clockwise
A1	1	0	0	0	0	0	0	1
B1	0	1	0	0	0	0	1	0
A2	0	0	1	0	0	1	0	0
B2	0	0	0	1	1	0	0	0
G1	0	0	0	0	0	0	0	0
G2	0	0	0	0	0	0	0	0

Table 3: Full step mode for unipolar stepper

2.2 half step mode for unipolar stepper motor.

	Clockwise								Anti-Clockwise
A1	1	1	0	0	0	0	0	1	1	1	0	0	0	0	0	1	1
B1	0	1	1	1	0	0	0	0	0	0	0	0	0	1	1	1	0
A2	0	0	0	1	1	1	0	0	0	0	0	1	1	1	0	0	0
B2	0	0	0	0	0	1	1	1	0	1	1	1	0	0	0	0	0
G1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
G2	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

Table 4: Half step mode for unipolar stepper