Both pulse rectifier and DC rectifier are devices that convert AC power into DC power, but they have some differences in working principle, performance characteristics and application occasions.

Working principle:
The pulse rectifier controls the current on and off through switching elements (such as thyristors, power tubes, etc.), converts AC power into pulsed DC power, and then converts the pulse waveform into a smooth DC voltage through a filter.
The DC rectifier is a process in which the negative half cycle or positive half cycle of the AC power is removed by the rectifier to obtain a unidirectional current.

Performance characteristics:
The pulse rectifier has high conversion efficiency and stability, and the output voltage fluctuation is small, which is suitable for occasions with high requirements for power quality.
The DC rectifier has a simple structure and low cost, and is usually used in applications with low power requirements or cost sensitivity.

Application occasions:
Pulse rectifiers are often used in occasions that require high efficiency and stable output, such as electronic equipment, power systems, etc.
DC rectifiers are often used in occasions where power requirements are not strict and the cost is low, such as household appliances, small equipment, etc.

In general, pulse rectifiers have higher efficiency and stability and are suitable for applications with higher power requirements; while DC rectifiers have a simple structure and low cost and are suitable for general power conversion needs.