串接电容Boost变换器DCM的均流控制策略

Current Sharing Control Strategy of Series Capacitor Boost Converter in DCM

研宄了串接电容Boost变换器电流断续模式(DCM)工作特性,阐述了变换器不均流和负向电流产生机理,并对此提出了非互补均流控制策略。该控制策略通过改变产生负向电流相的M0SFET时序,从而使得变换器避免出现产生负向电流的模态,并使两相输入电感电流能够均分。同时在该策略下工作的M0SFET耐压有一定降低。通过一台15W的实验样机验证了所提非互补均流控制策略的有效性。

The discontinuous current mode ( DCM) operating characteristics of the series capacitor Boost converter are studied.The mechanism of unsharing current and negative current generation is described.The non-complementary current sharing control strategy is proposed.The control strategy allows the converter to avoid modalities that generate negative currents by changing the MOSFET timing that produces the negative current phase, and to equalize the twophase input inductor current.At the same tim e,the withstand voltage of the MOSFET working under this strategy is reduced. The effectiveness of the proposed non -complementary current sharing control strategy is verified by a 15 W experimental prototype.