三相六开关Boost整流器的简化大信号模型

Simplified Big-Signal Model of Three-Phase Boost Six-Switch Rectifiers

三相Boost功率因数校正 (PowerFactorCorrection ,PFC)电路的分析和设计远比DC/DC变换器复杂 ,因为平均模型状态方程的系数矩阵是时变的。采用d q变换后 ,稳态系数阵为常数 ,但由于d、q通道相互耦合 ,设计难度大。文中结合等效拓朴变换和功率平衡法 ,把主电路简化成DC/DC变换器 ,使主电路的阶次降为二。简化电路与原始电路的参数对应关系非常简单 ,可用于主电路参数设计 ,模型经小信号线性化之后 ,还可在复频域设计输出电压调节器。小信号模型使该类电路的设计大为简化。对比性的仿真结果说明简化模型能反映原电路的主要动态特性。

A reduced-order big-signal model of three-phase pulse-width-modulation (PWM) rectifiers is proposed. The analysis and design of the three-phase boost Power Factor Correction (PFC) circuit is far more complex than the dc-to-dc converter, in that the coefficient of the state equation are time-variant. Although they become constants when in steady state in d-q frame, it is difficult to design due to the couple of the d- and q-channel. By combination of the topology transformation and Tellegen's theorem, the mains can be simplified to a boost dc-to-dc converter, thus reduce the mains' order to two, and the parameter of the simplified circuit is deduced. The proposed model can also be linearized to obtain the small-signal model. The small-signal model greatly simplifies the system design, therefore the traditional trial-and-error procedure is deserted. The contrast simulation results indicate that the simplified model can represent the low-frequency big-signal dynamic behavior of the six-switch three-phase PFC circuit.