DY3F Stepper Driver Performance introduction
The three-phase compound stepper motor is adopted with the rare earth material, with little
exhaustion of electromagnetism, high coversion efficiency and excellent dynamism compared to
other reaction stepper motor. The three-phase compound stepper can stably run with low noise, big
output and without stepping out. The three-phase stepper motor greatly improves the vibration and
noise driven by the sine wave current, and is the top grade motor.
Latest innovative technology
It is employed with the micro-electronic technology to embed the new generation high speed
monolithic processor into the drive unit to improve the control performance and simplify the circuit;
employed with AC servo control method to get AC servo run characteristics, and the three-phase sine
current drive output; the low voltage DC power supply in the drive unit use the switch power supply to
reduce the volume of power circuit and to get the reliable stability.
Micro step angle
It is employed with the vector division technology to control the min. angle of the motor rotating to
be 1/20（0.03°）of the step angle of motor. The mircro step control can ensure the stepper motor can
stably run with low speed, and its run effect approaches that of AC servo. The micro step drive unit is
matched with μm（0.001mm） grade CNC control device to realize μm grade min. movement, used for
machining the cambered surface, conical surface, thread and other workpiece, which can obviously
improve the fine effect of workpiece’s surface.
The output torque of stepper motor is in direct proportion, the input current capacity is in direct
proportion of voltage used by the amplifier of drive unit when it runs with the high speed. Presently,
the used voltage of most stepper motor is below DC150V, but that of DY3F reaches DC310V, so, it
still has the high torque output when it runs with the high speed.
The control parts are high integrated, the amplifier is employed with Mitsubishi new intellective
module with tight structure, terse circuit, few connectors, external wind cooling heat dissipation to
protect the dust from the machine inner, and with the over-temperature, overvoltage, low-voltage,
protection and alarm signal output.
Advanced stepper motor control method
The AC servo control method is applied the drive unit of three-phase compound stepper motor,
its input AC220V becomes to DC 310V after commutating, and then becomes three-circuit 310V
stepping sine wave current after pulse width modulation, and their fixed time sequence separately
flows through three-circuit wind, and each step corresponds to one step of motor rotating. Change the
motor’s speed by changing the frequency of sine current output by drive unit, and step amount output
by per rev confirms the angle of every step rotating.
According to the present electronic technology, the step amount of sine current is divided into
many. According to the theory, the step amount per rev is many, which is the subdivided technology.
The theory analysis and much experiement verify: when the subdivision amount exceeds 10, the skip
and the step-out appear after the motor has the load. So it is no actual meaning when the subdivision
amount exceeds 10. Presently, only three-phase sine current subidivision technology can ensure that
the motor output torque does not drop after subsidivision, and each step can be precisely positioned.
When the three-phase wind is connected with the sine current(three-phase current phase shift is
120°）, the current in the air gap of motor creates constant rotary maganetic potential of one space
maximum value, the space maganetic potential power and direction are related to the current ‘s
sequence and power of each phase, the current of drive unit in the motor wind is bidirectional grade
step wave(the current wve forms the sine wave when the grade amount increases infinitely), and the
phase difference of each current is 120°. The maganetic rotor tracks the rotor space maganetic
potential face to move to form the motor rotating, and when the space maganetic potential positionsto some point, the rotor also positions to the point to realize the precise positioning.
When some phase current changes one full period(other phase current also separately changes
one full period, only their step angle is different), the rotor of stepping motor rotates one pitch, and its
corresponding mechnical angle is 360°/Z2(Z2 is the teeth number of rotor). When the phase current
is divided into N step current value in one period, the rotor is located at the different positioning point
when it is in each step current, so the step angle of stepper motor is :а=360°/(NZ2), or the step
number per rev of motor is S=N×Z2. W hen each sine period is composed of 20 current step N, and
the teeth number Z2 of rotor is 50, the step angle of motor isа=360°/(NZ2)=360°/（20×50）=0.36°, the
needed pulse number per rev is S=N×Z2=20×50=1000.