FANUC's servo motors have smooth rotation characteristics, excellent acceleration capabilities and high reliability. With the built-in encoder, high-precision positioning and control can be achieved.
FANUC's servo motors can be divided into two categories: low-voltage servo motors (200V) and high-voltage servo motors (400V) according to their driving voltage. In addition, according to the characteristics of the motor, they can also be divided into two categories: αi series and βi series. kind. In the αi series servo motor, according to the difference in motor inertia and speed, it can be further divided into αiF series and αiS series; in the βi series servo motor, according to the difference in motor inertia and speed, it can be further divided into βiF series and βiS series. with the βiSc series.
Servo motors often drive the workbench of machine tools. The load damping of the workbench is the torque converted to the motor shaft, so generally servo motors use torque as the main parameter. Figure 6 is a typical servo motor torque characteristic curve.
Servo motor torque characteristic curve
Below 3000 r/min, the motor can output a basically constant torque (called rated torque). The servo motor usually works in this speed range, which is called the rated speed. Beyond this speed, the motor output torque will decrease. . The torque for continuous operation must not exceed the "continuous operation zone", and the torque during starting, braking, acceleration and deceleration must not exceed the "short-time operation zone".
Motor characteristic parameters
Rated speed: Nameplate speed is the speed at which the motor outputs rated power at rated voltage and frequency.
Rated torque: The long-term operating torque that the motor can output below the rated speed.
Rated power (rated output): The maximum power that a motor can output when running continuously for a long time.
Stall torque: Torque at zero speed, also known as static torque, locked-rotor torque, and self-locking torque. At this time, the motor acts as an electric brake to keep the load at the specified position, which is called normal Excitation braking during operation.
Maximum speed (max. speed): the maximum speed that the motor can reach.
Since the combination of speed and power is the horse's ability (referred to as horsepower), then this concept is applied to motors as electrical power. Then the servo motor power is equal to the product of speed and torque divided by 9550. The formula is as follows:
Pr: power, kW;
Tr: Torque, N·m;
nr: rotation speed, r/min.
The nameplate of a motor contains a lot of information and knowledge. In addition to the specifications of the motor, there is also a lot of knowledge about the principles of motor operation. Can you read it?
1.MODEL:
The meaning of model aiF12/4000 is as shown in the figure below. FANUC servo motors mainly include α (i) series and β (i) series. The two numbers in the model represent the stall torque (12NM) and the maximum speed (4000r/min) respectively.
Note: The "S" in aiS and biS means "STRONG motor using neodymium magnets", and the "F" in aiF means "motor using ferrite magnets (FERRITE)".
2.TYPE:A06B-2243-B100
For the order number of this motor, please refer to the FANUC Motor Selection Manual for details.
3.STALL TRQ. (stall torque)
The stalling torque is 12Nm, which is the torque (torque) of this motor at zero speed. It is also called static torque, locked-rotor torque, and self-locking torque, and is represented by Ts. At this time, the motor acts as an electric brake to keep the load at a designated position, which is called excitation braking during normal operation.
4. STALL AMP (stall current)
The stall current is 18A, which is the current in the winding at zero speed, represented by Is. Since the current is proportional to the torque, the stall current is larger than the rated current.
5.OUT PUT: 3KW (motor rated power): continuous power at rated speed Nr [min-1].
The rated output power of this motor is 3kW, which is the maximum power that the motor can output during continuous operation for a long time, represented by Pr (the subscript r means rated). The motor converts electrical energy into mechanical energy output, so the rated power on the mechanical side is the product of rated torque (torque) and rated speed (speed), and on the electrical side it is the product of rated voltage and rated current.
6. AMP (AC Current)
The rated current of the motor is 14A, which is the current flowing in the stator winding of the motor, represented by I.
7. SPEED (speed)
The rated speed is 3000r/min, which is the speed at which the motor outputs rated power at rated voltage and frequency. It is also called the nameplate speed and is represented by nr.
According to the following formula, ns=nr=3000r/min, f1=200Hz, it can be seen that the number of stator pole pairs p of the servo motor is 4.
8. FREQ (frequency)
The rated frequency is 200Hz, which refers to the frequency output by the servo amplifier that causes the servo motor to rotate at the rated speed, represented by f1. This shows that the servo motor is frequency-regulated and speed-regulated.
9.WINDING CON. (winding connection)
The winding connection is star (Y) type, as shown in Figure 5.
Figure 5 Star stator winding connection
Therefore, based on the following formula, U=141V, I=14A, we can calculate that the electric power P of the motor is approximately 3.0kW. (P=1.732*U*I*power factor 0.9)
10. VOLT (voltage)
The rated voltage of the motor is 141V, which is the voltage applied across the stator winding of the motor, represented by U.
11. INS CLASS (insulation level)
The insulation grade is F class.
12. PHASE (current phase number)
The number of current phases is 3 phases, and most industrial motors are three-phase motors.
