Toshiba G7 Series Applications Workbook page 35

Sensorless Vector Control (Speed)
Introduction
Toshiba's G7 can, when properly configured, provides speed regulation as great as 0.1% from 0.6Hz
to 60.0Hz with no external feedback. This control method is referred to as Sensorless Vector Speed
Control.
To maximize the performance of the motor/drive combination, the G7 must be tuned to the motor.
G7s have mathematical models of all standard efficient and premium efficient Houston-made Toshiba
motors stored in a matrix memory. These motor mathematical models are used by the drive to
increase the motor's low speed torque and to reduce the load's affect on RPM (when compared to its
performance on a V/Hz drive). If a non-Toshiba motor is being used, the G7 can model the motor by
performing an 'auto-tune' or by manual setting of the motor data.
Sensorless Vector Control should not be used on:
Multiple Motor Applications (applications where more than one motor is connected to the G7)
Applications where load end inductors, long lead filters, or output transformers are used
High-speed spindle motors
Motors designed for high slip (NEMA design D)
Motors larger than or more than 2 sizes smaller than the G7's nominal Horse Power rating
It is necessary to define the type and size of the motor to the G7 prior to using either the G7's internal
tables or auto-tuning. The G7 requires the following information:
The number of motor poles may be determined by the motors' base frequency and it's nominal rated
RPM.
The chart below may be used to determine the setting for motor poles
If the motor nameplate does not list kW, the motor's horsepower may be converted to kW by
multiplying Hp by 0.745.
For additional assistance, please contact Toshiba Adjustable Speed Drive Marketing Dept. at (800) 872-2192
efesotomasyon.com -Toshiba inverter,drive,servo,plc
Number of motor poles
Capacity (size) of motor in kW
Motor Type
Base Nominal
Frequency RPM
60 3600
60 1800
60 1200
50 3000
50 1500
50 1000
Motor Poles
2
4
6
2
4
6
12
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