YASKAWA GA800 Series - Page 27

Receiving
1
1.3 Features and Advantages of Control Methods
YASKAWA SIEPC71061737B GA800 Drive Technical Reference 27
Table 1.5 OLV, CLV and AOLV Features and Advantages of Control Methods
Control method
selection
Open Loop Vector
(OLV)
Closed Loop Vector
(CLV)
Advanced OpenLoop Vector
Control
(AOLV)
Notes
Controlled Motor Induction Motor -
Parameter Setting
A1-02 = 2
(Default)
A1-02 = 3 A1-02 = 4 -
Basic Control Open Loop Current Vector Control
Closed Loop Current Vector
Control
Open Loop Current Vector Control -
Main Applications
• General-purpose variable speed
control
• Applications in which high
performance is necessary
without machine encoders
Very high-performance control with
motor encoders
Example: High-precision speed
control, torque control, torque
limits
Sensorless vector control with
speed control
• General-purpose variable speed
control
• Applications in which high
performance is necessary
without machine encoders
-
PG Option Card Not necessary Necessary (PG-B3 or PG-X3) Not necessary -
Maximum Output
Frequency
590 Hz 400 Hz 120 Hz -
Speed Control Range 1:200 1:1500 1:200
This is the range of variable control.
When you connect and operate motors in
this mode, think about the increase in motor
temperature.
Starting Torque 200% / 0.3 Hz
*1
200% / 0 min
-1
*1
200% / 0.3 Hz
*1
This is the motor torque that the drive can
supply at low speed during start-up and the
related output frequency (rotation speed).
You must think about drive capacity and
motor capacity when a large quantity of
torque is necessary at low speed.
Auto-Tuning
*2
Rotational, Stationary, and Line-to-
Line Resistance
Rotational, Stationary, and Line-to-
Line Resistance
Rotational, Stationary, and Line-to-
Line Resistance
Automatically tunes electrical motor
parameters.
Torque Limits
*2
Yes Yes Yes
Controls maximum motor torque to prevent
damage to machines and loads.
Torque Control
*2
No Yes
Yes (Although NOT low speeds of
approximately 10% or less)
Directly controls motor torque to control
tension and other parameters.
Droop Control
*2
No Yes Yes
Sets load torque slip for motors. Distributes
motor loads.
Zero Servo Control
*2
No Yes No
Locks servos without an external position
controller to prevent movement caused by
external force.
Speed Search
*2
Yes - Yes
Immediately estimates (or detects) motor
speed and direction when coasting to a stop
to quickly start-up the drive without
stopping the motor.
Automatic Energy-
saving Control
*2
Yes Yes No
Automatically adjusts the voltage applied to
motors to maximize motor efficiency for all
load sizes.
High Slip Braking
(HSB)
*2
No No No
Increases motor loss to let the motor
decelerate faster than usual without a
braking resistor. Motor characteristics have
an effect on this function.
Feed Forward Control
*2
No Yes Yes
Compensates effects of the system inertia to
increase the speed precision when the load
changes.
KEB Ride-Thru
Function
*2
Yes Yes Yes
Quickly and safely stops the motor during
power loss and automatically starts
operation at the previous speed when
restores power without coasting the motor.
Overexcitation
Deceleration
*2
Yes Yes Yes
Sets the V/f higher than the setting value
during deceleration to increase motor loss
and decrease deceleration time.
Overvoltage
Suppression Function
*2
Yes Yes Yes
Adjusts speed during regeneration to prevent
overvoltage.
*1 Select the drive capacity and motor capacity accordingly.