Analysis, simulation and experimental study of chaos in the buck converter

A buck DC-DC power converter, whose input voltage is controlled by naturally sampled, constant-frequency PWM (pulse width modulation), is operated in the continuous conduction mode. Two versions are treated, a first-order and second-order circuit. Their behavior is modeled analytically and numerically. For certain values of the circuit parameters instability occurs. Strange phenomena of multiple pulsing, shipped cycles, subharmonics, and chaos are predicted theoretically and observed experimentally, including a period-doubling route to chaos. There is good agreement between theory and experiment.<>