Toshiba T300MVi MEDIUM VOLTAGE, Instruction Manual

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- 41
PGA
PGB
Speed Detection
Pulse count
Pulse interval
Rotation direction
Speed
feedback
Position
feedback
CS_RES_TYPE = 1
CS_PG_CNT = PG PPR
FLG_DIFF_PG = 0
CIRCUIT OPERATION (cont’d)
Speed Feedback (Option)
As an option, a Resolver or a Pulse Generator (PG) can be selected for speed feedback. Speed
control with a Tach Generator is not available because Tach Generator performance is poor.
Resolver
A resolver is an analog feedback device that used for speed feedback. Two sinewave excitation
signals (sine and cosine) are sent to the resolver and two signals (sine and cosine) are returned to the drive.
The use of these two phase shifted signals allows the direction rotation to be determined. The position of
the motor rotor is determined by the phase difference between the excitation and return signals. The speed
is found from the change in this position over time.
PG
A signal is detected from a single ended PG attached to the motor and converted to a speed.
Detection is performed according to the pulse interval measurement system. This system converts a
signal to a speed based on the fact that the interval (time) between pulses input is inversely proportional to
the speed. The maximum input frequency is 10kHz.
PG Speed Detection