Lenze 8400 motec - Manual (Page 106)

5 Motor control (MCTRL)
5.6 V/f characteristic control - energy-saving (VFCplusEco)
106 Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05
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5.6 V/f characteristic control - energy-saving (VFCplusEco)
With the energy-saving V/f characteristic control mode (VFCplusEco), the motor voltage of the
inverter is detected by means of a linear characteristic depending on the field frequency to be
created or the motor speed. Moreover, a cosϕ control and the resulting voltage reduction causes the
motor to be always operated in the optimum efficiency range (reduction of copper losses in the
asynchronous machine).
• Hence, these are the advantages of this motor control mode:
• Good robustness
• Easy parameter setting
• High energy efficiency (lower heating of the motor in partial load operational range)
• Same speed accuracy and maximum torques as with VFCplus
• Predestinated application areas of this motor control mode are materials handling technology
and pump and fan systems.
• This motor control mode serves to improve efficiency of standard asynchronous machines with
efficiency class IE1 (standard IEC 60034-30 2008) in the range 0 … M
efficiency_max
between
0 … 20 % (Ø 5 … 10 %).
• Description of M
efficiency_max
: Indicates the torque [%] of M
rated_motor
, where the motor has
the max. efficiency.)
• In case of asynchronous machines with a higher energy efficiency class (IE2 and IE3), the
absolute energy saving of the motor control mode is lower due to improved efficiency of the
machine. However, energy saving is still achieved in a higher load range.
• M
efficiency_max
is performance-related and listed in the following table for some power values
of the energy efficiency class IE1 and IE2:
M
Efficiency_max
(related to Mrated_motor)
Power IE1 IE2
0.25 kW 75 %
0.75 kW 65 % 75 %
2.2 kW 55 % 85 %
7.5 kW 30 % 45 %
22 kW 23 %
45 kW 21 %