谷值电流型脉冲序列控制开关变换器及其能量建模研究

脉冲序列控制是针对工作于电感电流断续导电模式的开关变换器提出的一种非线性、离散控制技术.当开关变换器工作在电感电流连续导电模式时,脉冲序列控制开关变换器存在低频振荡现象,严重影响了脉冲序列控制开关变换器的稳态及瞬态性能.针对这一问题,本文提出一种谷值电流型脉冲序列控制方法,将脉冲序列控制的应用范围从电感电流断续导电模式扩展到电感电流连续导电模式.建立了谷值电流型脉冲序列控制开关变换器的能量迭代模型,并与传统脉冲序列控制开关变换器的能量模型进行对比.结果表明谷值电流型脉冲序列控制电感电流连续导电模式开关变换器具有与传统脉冲序列控制电感电流断续导电模式开关变换器相同的能量传递模式,从而在根本上消除了传统脉冲序列控制电感电流连续导电模式变换器存在的低频振荡现象.

Valley current mode pulse train control switching converter and its energy model analysis

Pulse train (PT) control technique is a novel discrete control technique for switching converter operating in discontinuous conduction mode (DCM). When the inductive energy storage is not zero, the low-frequency oscillation phenomenon may occur in PT controlled switching converters operating in continuous conduction mode (CCM). The low-frequency oscillation phenomenon will seriously affect the steady and transient performances of switching converters. In order to solve this problem, valley current mode pulse train (VCM-PT) control technique, which extends the application range from DCM to CCM, is proposed in this paper. The energy model of VCM-PT controlled switching converter is derived and compared with the energy model of PT controlled switching converter. Result indicates that the VCM-PT controlled CCM switching converter has the same energy transfer mode as the traditional PT controlled DCM switching converter and can eliminate fundamentally the low-frequency oscillation phenomenon.
Keywords： switching converter pulse train continuous conduction mode energy model