5motor control (mctrl) – Lenze 8400 motec User Manual
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Lenze · 8400 motec · Reference manual · DMS 4.1 EN · 08/2013 · TD05
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5
Motor control (MCTRL)
5.3
Selecting the control mode
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V/f characteristic control (VFCplus)
The V/f characteristic control (VFCplus) is a motor control mode for standard frequency inverter
applications based on a simple and robust control process which is suitable for the operation of
machines with linear or square-law load torque characteristic (e.g. fans). Furthermore, this motor
control mode is also suitable for special motors. Due to the low parameterisation effort,
commissioning of such applications is fast and easy.
The V
min
-boost (
) and slip compensation (
) required for optimising the drive
behaviour are dimensioned for machines with power adaptations to the inverter in the Lenze
setting.
V/f characteristic control (VFCplus)
Energy-saving V/f characteristic control (VFCplusEco)
In contrast to the V/f characteristic control mode (VFCplus), this motor control mode uses a cosϕ
control in partial load operational range to automatically reduce the power loss in the machine
(energy optimisation).
The motor data required for the cosϕ control and the V
min
boost (
) and slip compensation
(
) required for optimising the drive behaviour are dimensioned for machines with power
adaptations to the inverter in the Lenze setting.
The required motor data (motor rotor resistance, motor stator resistance, motor stator leakage
inductance and mutual motor inductance) only affect the extent of energy optimisation but not the
stability.
In case of applications with dynamically very high sudden load variations from the unloaded
operation, this motor control mode should not be used since a motor stalling cannot be excluded.
Energy optimisation for dynamic applications is not possible with this motor control mode.
V/f characteristic control - energy-saving (VFCplusEco)
V/f control (VFCplus + encoder)
From version 02.00.00
The V/f control can be selected for operating asynchronous motors with speed feedback. With this
motor control, a slip regulator can be additionally parameterised which adjusts the actual speed
value dynamically to the speed setpoint.
V/f control (VFCplus + encoder)