Input Rectifiers with Semifast Diodes for DC Link

Fig. 1 Input rectifier bridges circuit diagrams Fig. 2 Reverse recovery waveforms comparing standard rectifier (a) to semifast rectifier (b) Switching power semiconductors are used in inverter systems with a DC-link. Due to high switching frequencies, harmonics and line distortions may be generated. It is important that new designs reduce these disturbances and fulfill the EMI filtering requirements of VDE 0871 and other applicable standards.