Parameter design method of phase-shifted full-bridge converter based on zvs load range

Abstract

The invention relates to a parameter design method of a phase-shifted full-bridge converter based on a ZVS load range, comprising: according to the input voltage V in with the output voltage V o gain, and the system allows the maximum duty cycle loss D loss_max , to calculate the primary and secondary turns ratio n of the transformer; according to the output filter inductance L 0 The principle of volt-second balance, and the output inductor current ripple coefficient α, calculate the output filter inductor L 0 ; According to the volt-second balance principle of the resonant inductance Lr, the structure is about the ZVS soft switching range λ and at λI o The duty cycle is lost under load condition D loss_λ function λ 1 (L r ,D loss_λ ); according to the realization condition of lagging arm soft switching, take the energy stored in the resonant inductor Lr and the lagging arm parallel capacitor C lag The energy required to complete the commutation is equal to the critical condition, and the constructor λ 2 (L r ,D loss_λ ); the solution satisfies the critical soft-switching condition λ 1 (L r ,D loss_λ )=λ 2 (L r ,D loss_λ ) set M(λ,L) of all points r ,D loss_λ ), determine the optimal solution (λ,L r ,D loss_λ ). This method can realize the simple and intuitive screening and design of the circuit parameters of the phase-shifted full-bridge ZVS converter.

Description

technical field [0001] The invention belongs to the technical field of ZVS converters, in particular to a parameter design method of a phase-shifted full-bridge converter based on a ZVS load range. Background technique [0002] The phase-shifted full-bridge ZVS converter can make full use of the parallel capacitance and resonant inductance of the power device to realize the zero-voltage conduction of the power switch, which not only reduces the conduction loss of the switch tube, but also increases the switching frequency of the power tube and reduces the The volume and weight of the system are reduced, and the conversion efficiency of the system is improved. Therefore, the phase-shifted full-bridge ZVS converter is widely used in DC-DC direct current power supply. [0003] Such as figure 1 Shown is the basic topology of the main circuit of the ZVS phase-shifted full-bridge DC-DC converter, where Q1 and Q3 are leading transistors, Q2 and Q4 are lagging transistors, D1~D4 a...

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Problems solved by technology

However, there is no systematic research and analysis for the complex parameter optimization design of phase-shifted full-bridge converters. For example, literature: Optimization and parameter design of phase-shifted full-bridge ZVS converters. Electronic Devices, 2016,39(3):650 -654, for the phase-shifted full-bridge ZVS converter, introduced its working principle and designed the key component parameters of the resonant main circuit in detail, but it did not quantitatively analyze the key parameters that affect the ZVS of the lagging arm, such as resonant inductance and IGBT dead time

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