The matters needing attention in selection and application of step motor in

Stepper motor selection

The stepping motor step angle (related to the number of phases), static torque, and the current three elements. Once identified three major elements, stepping motor typeis fixed.

1, the current selection

Motor torque static like, because the current parameters of different, its operating characteristic difference is very big, can be based on the torque frequencycharacteristic curve, determine the motor current.

2, the choice of step angle

Motor step angle depends on the load precision requirements, the minimum resolutionof the load (equivalent) converted to the motor shaft, each equivalent motor should gomuch angle (including deceleration). Step motor shall be equal to or less than the angle. Stepper motor step angle markets generally have 0.36 degrees /0.72 degrees(five phase motor), 0.9 degrees /1.8 degrees (two, four phase motor), 1.5 degrees /3 degrees

(three-phase motor) etc..

3, the selection of the static torque

Dynamic torque of the stepping motor was difficult to determine, we are often the first to determine the static torque motor. Static moment choice is based on the load motorwork, can be divided into two kinds of inertia load and friction load and load. Singleinertial load and single friction load is not exist. When start directly (usually by the low speed) two load should be considered when starting, acceleration mainly consider theinertial load, constant speed operation into just considering the friction load. In general, static moment should be 2-3 times the friction load in static torque, once selected, the frame and the length of the motor can be determined (geometry).

Points for attention in application

1, high precision, using mechanical deceleration, improve the motor speed, or using high subdivision drive to solve, also can use 5 phase motor, but the whole systemmore expensive, small manufacturers, the eliminated argument is the layman;

2, the stepper motor is best not to use the step state, big vibration whole step state;

3, the theory of step motor in low-speed occasions - RPM less than 1000 rpm (0.9 degrees 6666PPS), preferably in the 1000-3000PPS (0.9 degrees) between the use of, can be through a speed reducer to make it here at the motor work, high work efficiency, low noise;

4, a large moment of inertia load should be selected large frame motor;

5, due to historical reasons, only the nominal motor voltage of 12V using 12V, the voltage value not other motor driving voltage V value, according to the drive selectiondriving voltage (recommended: 57BYG by DC 24V-36V, 86BYG uses the DC 50V,110BYG higher than the DC 80V), of course, a voltage of 12 volts in 12V constant pressure drive you can also use other driving power, but to consider the temperature rise;

6, should follow the first election after the principle of motor drive;

7, the motor at high speed or high inertia load, generally do not start in the speed,and by gradually raising frequency speed, a motor lose step two can reduce the noiseand can improve the positioning precision stop;

8, the motor should not work in the vibration area, if must solve the voltage and the current through the change or add some damping;

9, in the 600PPS motor (0.9 degrees) the following work, should be a small current and large inductance, low voltage to drive.