Toshiba VF-AS1 instruction manual Operating a permanent magnet motor, VF5 VF4 VF3 VF1 VF2

E6581301

Base frequency voltage 1 ￿￿￿

V/f 5-point setting

Output voltage

[V]/[%]

￿￿￿￿

￿￿￿￿

￿￿￿￿

￿￿￿￿

￿￿￿￿

￿￿

0

VF5

VF4

VF3

VF1

VF2

￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿

Output frequency [Hz]

￿￿

Base frequency 1

Note 1: Restrict the amount of torque to boost (￿￿) to 3% or so. Boosting the torque too much may impair the linearity between points.

Note 2: If the V/f 5-point is set within the diagonally shaded area in the figure below, the V/f 5-point is placed automatically on the boundary line (heavy line in the figure).

!	Voltage
	100%
5
	: Area in which the
	V/f 5-point cannot
	be set!
	0	￿￿!
	￿￿× 0.4413!		Frequency

6) Operating a permanent magnet motor

Setting of V/f control mode selection ￿￿=￿ (PM control)

Permanent magnet motors (PM motors) that are light, small in size and highly efficient, as compared to induction motors, can be operated in sensorless operation mode. Note that this feature can be used only for specific motors. For more information, contact your Toshiba distributor.

7)Operating the motor at periodic speeds by means of a motor speed sensor

Setting for V/f control mode selection ￿￿=￿ (PG feedback control)

Set ￿￿ to ￿ to operate the motor at periodic speeds.

A PG feedback device (optional) is needed. In addition, a motor with a speed sensor (encoder) should be used.￿ Use this setting when operating a motor two or more ranks lower in capacity than the inverter at periodic speeds. Note that the accuracy obtained by ￿￿=￿ is lower than that obtained by setting ￿￿ to ￿. Also, ￿￿ should be set to ￿ to perform torque control. ￿￿ cannot be set to ￿ in such a case.

Output torque decreases considerably in regenerative low speed operation (motor slip frequency or less). Set ￿￿ to

￿if regenerative low speed torque is necessary.

"Motor constant must be set.

The motor constant can be set in any of the following two ways:

1) Automatic setting

Enter the following information that is indicated on the motor nameplate, and then execute the auto-tuning 1 command (Set ￿￿￿￿ to ￿, and then reset ￿￿￿￿ to ￿.).

<Information indicated on motor nameplate>

￿￿(Base frequency), ￿￿￿ (Base frequency voltage), ￿￿￿￿ (Motor rated capacity), ￿￿￿￿ (Motor rated

current), ￿￿￿￿(Motor rated rotational speed) ￿ Refer to 6.22 selection 2.

2) Manual setting

Set each motor constant manually. ￿ Refer to 6.22 selection 3.

E-14