2. The Multiple Frequency Problem

Several strategies exist to deal with the multiple frequency problem:

  1. Divide and Conquer - Use a DC Input
    • Circuit is now a DC/DC converter
    • Can run POP/AC
  2. Choose your frequencies to be harmonic multiples (limited to fixed frequency converters)
    • e.g. 100kHz switching frequency and 50Hz line frequency
    • You can POP on 50Hz, and the 100kHz appears as a 2000th harmonic!
  3. Brute force it - Multi-Tone AC Analysis
    • Inject multiple time-domain sinusoidal frequencies into the loop
    • Extract the frequency response with Fourier techniques