Toshiba Toshiba Schneider Inverter Corporation
Harmonics supprenssion PWM converter

Harmonics supprenssion and power factor/comprehensive efficiency improving

Energy saving by SC7
SC7 series is harmonics suppression converter to conect inverter drive equipment.
SC7 control input voltage and input current to same phase (power factor=1) for harmonics suppression.
Therefore, to use this SC7 will be energy saving by harmonics suppression and power factor/comprehensive efficiency.

Outline of comprehensive efficiency improving
Power supply equipment efficiency Improving by power factor=1 control.
Capacity of breaker
Cable size
Reducing capacity of wiring apparatus by decreasing motor current and input current.
Inverter efficiency Improving by inverter's inside loss; Rectifier loss is nothing.
Motor driving voltage Keep the motor driving voltage to high level without voltgae drop as rector.
Motor efficiency Improving by decreasing motor current for high motor driving voltage.

- Comparison of needed input capacity:
Inverter only:
  Input Capacity = (1.732*Vout*Iout)/(eff1 * cosX)
Connected SC7:
  Input Capacity = (1.732*Vout*Iout)/eff2

Vout: Inverter's output voltage
Iout: Inverter's output current
eff1: Inverter's efficiency
eff2: Inverter and SC7 efficiency
cosX: Inverter's input power factor

Inverter's input power factor:
  Reactor installing: about 0.8
  nothing: 0.4~0.6

Interter's input power factor depends on capacity of power supply and impedance of wiring.

- In case of driving 160kW motor (440V-250A)
Condition Inverter/Converter efficiency Total power factor Necessary input Capacity
Inverter with DC choke 0.96 0.8 248.1 kVA
Inverter with SC7 0.98 x 0.98 = 0.96 1 198.5 kVA

Condition Input current Cable size MCCB flame Selected transformer capacity
Inverter with DC choke 253 A 100 mm2 400 AF 300 kVA
Inverter with SC7 194 A 60 mm2 300 AF 200 kVA