B3: Speed Search - YASKAWA AC Drive-A1000 Technical Manual

No.
b2-08
When a Run command is issued, the DC current level injected into the motor changes linearly from the level set to b2-08 to
the level set to E2-03 within the time set to b2-03.
The level of the DC current injected to the motor is limited to 80% of the drive rated current or to the motor rated current,
whichever value is smaller.
Note: 1. If b2-08 is set below 100%, it can take a relatively long time for flux to develop.
2. If b2-08 is set to 0%, the DC current level will be the DC Injection current set to b2-02.
3. As DC Injection can generate a fair amount of noise, b2-08 may need to be adjusted to keep noise levels acceptable.
n b2-12: Short Circuit Brake Time at Start
Short Circuit Braking can be used in OLV/PM and AOLV/PM. Shorting all three motor phases produces a braking torque in
the motor and can stop a coasting motor before starting it again. Disabled when set to 0.00 s.
No.
b2-12
Note: Short Circuit Braking cannot prevent a PM motor from being rotated by an external force. Use DC Injection to prevent the load from rotating
the motor.
n b2-13: Short Circuit Brake Time at Stop
The Short Circuit Braking described for parameter b2-12 can also be applied at the end of deceleration to completely stop high
inertia loads. Short Circuit Braking is initiated for the time set in b2-13 when the output frequency falls below the higher of
the values b1-02 and E1-09. Disabled when set to 0.00 s.
No.
b2-13
n b2-18: Short Circuit Braking Current
Sets the current level for Short Circuit Braking operation as a percentage of the motor rated current. The Short Circuit Braking
current cannot be higher than the drive rated current (120% for Normal Duty, 150% for Heavy Duty), although a higher current
level can be set using b2-18.
No.
b2-18
u

b3: Speed Search

The Speed Search function allows the drive to detect the speed of a rotating motor shaft that is driven by external forces and
start the motor operation directly from the detected speed without first stopping the machine.
Example: When a momentary loss of power occurs, the drive output shuts off and the motor coasts. When power returns, the
drive can find the speed of the coasting motor and restart it directly.
For PM motors, only parameter b3-01 is needed to enable Speed Search.
For induction motors, the drive offers two types of Speed Search than can be selected by parameter b3-24 (Speed Estimation
and Current Detection). Both methods are explained below and followed by a description of all relevant parameters.
YASKAWA ELECTRIC SIEP C710616 31B YASKAWA AC Drive – A1000 Technical Manual
Name
Magnetic Flux Compensation Value
Output frequency
b2-08
Magnetizing Current
Reference
Figure 5.15 Magnetic Flux Compensation
Name
Short Circuit Brake Time at Start
Name
Short Circuit Brake Time at Stop
Name
Short Circuit Braking Current
Setting Range
E2-03
Time
b2-03
Setting Range
Setting Range
Setting Range
5.2 b: Application
Default
0 to 1000%
Default
0.00 to 25.50 s
Default
0.00 to 25.50 s
Default
0.0 to 200.0%
0%
0.00 s
0.50 s
5
100.0%
135