基于多准比例谐振的单相双向AC/DC变换器G2V/V2L模式统一控制策略研究

Research on a Multi-QPR-Based Unified Control Strategy for a Single-Phase Bidirectional AC/DC Converter in G2V/V2L Modes

摘要: 针对单相双向OBC (车载充电机)在G2V (充电)与V2L (供电)模式下控制结构不统一、谐波抑制不足的问题，本文以“单相H桥AC/DC + 隔离型CLLLC谐振DC/DC”的级联拓扑为对象，提出面向前级AC/DC的多准比例谐振统一电流控制策略。两种模式共用同一“电压外环 + (PI并联多准比例谐振)电流内环”内核，仅切换外环控制对象与电流参考生成方式：G2V采用母线电压PI外环并结合PLL(锁相环)生成正弦电流参考；V2L采用基于QPR (准比例谐振)的输出电压外环生成电流参考以合成220 V/50Hz正弦电压。Multi-QPR (多准比例谐振)包含基波及3/5/7次等通道，对目标频点提供高增益实现选择性补偿。仿真结果表明，相比传统PI控制，所提策略可显著降低G2V电流THD (总谐波畸变率)，并改善V2L输出电压THD，从而提升系统电能质量。

Abstract: To address the non-unified control structure and insufficient harmonic suppression of a single-phase bidirectional On-Board Charger (OBC) operating in both Grid-to-Vehicle (G2V) charging and Vehicle-to-Load (V2L) supplying modes, this paper investigates a cascaded topology consisting of a single-phase H-bridge AC/DC stage and an isolated CLLLC resonant DC/DC stage, and proposes a unified current control strategy for the front-end AC/DC converter based on a Multi-Quasi-Proportional Resonant (Multi-QPR) controller. In both modes, the same control core—an outer voltage loop plus an inner current loop implemented by PI in parallel with Multi-QPR—is reused, while only the outer-loop controlled variable and the current-reference generation method are switched. Specifically, in G2V mode, a DC-bus voltage PI regulator together with a Phase-Locked Loop (PLL) generates the sinusoidal current reference; in V2L mode, a QPR-based output-voltage loop produces the current reference to synthesize a 220 V/50Hz sinusoidal output. The proposed Multi-QPR includes resonant channels at the fundamental and selected 3rd/5th/7th harmonics, providing high gain at targeted frequencies for selective compensation. Simulation results demonstrate that, compared with conventional PI control, the proposed strategy significantly reduces the grid current THD in G2V mode and improves the output voltage THD in V2L mode, thereby enhancing the overall power quality.