A 3kW Soft Switching DC-DC Converter

A 3kW Soft Switching DC-DC Converter

  • Date of Publication 06 Feb 2000
  • Meeting end date 10 Feb 2000
  • On page 86-92
  • Location New Orleans, Louisiana, USA
  • Conference/Proceedings Applied Power Electronics Conference and Exposition, February 2000. APEC '00. Conference Proceedings 2000, Fifteenth Annual
On page(s) 86-92
Location New Orleans, Louisiana, USA
Meeting date 02/06/2000 – 02/10/2000
Conference/Proceedings Applied Power Electronics Conference and Exposition, February 2000. APEC ’00. Conference Proceedings 2000, Fifteenth Annual

This paper will present a circuit technique designed to reduce the negative impact of reverse recovery in the rectifiers for high output voltage converters. This technique works by combining reduced amplitude of the reverse recovery current and a lower voltage across the rectifier during the turn off commutation. Another major advantage of the proposed circuit is the fact that the current reflected in the primary is shaped to a triangular form with a low dI/dt during the turn on of the main switch. This will allow the completion of the resonant transition to zero voltage across the primary switchers. In the secondary section the reverse recovery current is reduced due to low dI/dt current slope at turn off and the reverse voltage is clamped to the output voltage. The maximum reverse recovery voltage does not exceed the output voltage. The soft commutation in the primary section and the secondary allows a higher frequency of operation without penalty in efficiency. A 3kW converter for on board battery charger in electric vehicles provides an output voltage between 170V to 380V. Efficiency above 96% is obtained at a switching frequency of 250 kHz while the power density of the converter exceeds 100W/inch3