LS ELECTRIC SV-iS7 Series, Руководство пользователя

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Learning Advanced Features
256
Code Description
noise from the motor.
CON-05 PWM
Mode
The heat loss and leakage current from the inverter can be reduced by
changing the load rate option at CON-
05 (PWM Mode). Selecting “1
(LowLeakage PWM)” reduces heat loss and leakage current, compared to
when “0 (Normal PWM)” is selected. However, it increases the motor noise.
Low leakage PWM uses a two-phase PWM modulation mode, which helps
minimize degradation and reduces switching loss by approximately 30%.
Item
Carrier Frequency
0.7 kHz 15 kHz
LowLeakage PWM Normal PWM
Motor noise
↑ ↓
Motor temperature ↑ ↓
Inverter heat Loss ↓ ↑
High frequency ↑ ↓
Inverter output current
wave form
Bad Good
Inverter noise ↓ ↑
Inverter leakage current
↓
↑
• The factory default carrier frequency for 90 – 160 kW model types is 3 kHz . The figure in the
red box (D: 5.0) is a factory default carrier frequency for models types up to 75 kW,
provided for your reference only.
• Since low carrier frequencies can transmit a much higher frequency than the capacity of
the output current, an increase in motor loss will occur. Some motors may stall due to
increased high frequency current and lack of torque may cause the inverter to stop.