Comprehensive steady-state analytical model of a three-phase diode rectifier connected to a constant DC voltage source

This study deals with the analytical modelling of the steady-state operation of a three-phase diode rectifier whose dc bus is connected to a constant voltage source. Such a system exhibits several operation modes that are fully investigated. Analytical expressions of the boundaries of each mode as well as the average dc and the rms ac currents are deduced as a function of the ac and dc parameters, including voltage drops across diodes. They allow us to evaluate the power delivered to the dc bus as well as the efficiency of the conversion in each mode of operation. These results can also be extended to practical rectifiers with bulk dc capacitors and allow for performing parametric analyses and optimisation in the design of drives or permanent magnet synchronous generators directly connected to a diode rectifier. The theoretical results are validated by experimental tests.