a new type of the passive non - dissipative snubber with a single saturable reactor improves the performance of the boost converter used as a front - end active power factor correction in two critical areas : excess voltage stresses caused by high voltage spikes on input high voltage switching transistor of the boost converter is eliminated and emi noise is much reduced . the high voltage spike energy instead of being dissipated as in a dissipative snubber circuits is recovered resulting in increased conversion efficiency . high voltage spike elimination also allows use of lower voltage rated devices with lower on resistance , hence further increasing the efficiency of the pfc boost converter .