The non-auxiliary-circuit-based soft switching technology enables zero voltage switching (ZVS) turn-on of power devices

representing a critical approach to achieve high power density and efficiency in power converters. However

conventional soft-switching techniques based on variable frequency control are subject to wide switching frequency variation ranges and significant current ripples. By leveraging the controllable circulating current characteristics of parallel bridge arms

this paper innovatively proposed a trapezoidal current mode (TZCM) soft-switching modulation strategy based on phase-shift control and extended it to 2N-parallel bridge-arm systems. By constructing one pair of self-balancing carriers with inherent self-balancing circulating current characteristics

and adjusting the peak circulating current by dynamically adjusting the phase-shift angle

the proposed method maintained fixed-frequency boundary soft-switching operation across the full modulation range. At last

experimental verification was conducted on a 5 kVA single-phase six-parallel-arm SiC prototype

thereby confirming the effectiveness of the proposed strategy. The results demonstrates that this method can effectively reduce the turn-on loss of power devices and provide a reliable technical path for the fixed-frequency and high-efficiency operation of converters.