The Inversine Advanced Universal Sine-wave Filter (AUSF) is designed to address the problems resulting from pulse width modulation. It is a low pass filter with cutoff frequency well below the switching frequency of the inverter.

The AUSF is much more than a simple dV/dT filter and will:
  • substantially reduce voltage rise time (dV/dt)
  • convert output voltage to near sinusoidal waveform (<3%)
  • prevent transient overvoltages at motor terminals
  • lower harmonic losses in the motor
  • reduce motor noise
  • reduce motor and cable insulation stress
  • extend life of the motor and ASD
  • When Motor does not have adequate insulation for ASD duty
  • Using a number of parallel motors
  • Long Motor cable length
  • When Step-up/Step-down transformer is used between ASD and motor
  • There are specific requirements for peak voltage level and dV/dt rise time
  • Motor noise needs to be reduced
  • Maximum safety and reliability is needed in hazardous environments
  • Submersible pumps with long motor cables used in the oil & gas industry