单相高频链逆变拓扑由高频变压器、一次侧高频逆变器、二次侧矩阵/周波变换器和输出滤波器构成,既有隔离型功率变换及能量双向流动的优点,也有双向开关换流控制难度高的缺点.针对此拓扑提出一种解结耦单极性移相调制策略,能够无需借助辅助电路与功率管的重叠换流技术,即可实现周波变换器中所有功率管的零电压开关(ZVS)自然换流及滤波电感无过电压冲击自然续流.在此基础上,研究了一种优化死区设置方法,有效地改善了单极性移相调制策略存在的输出电压过零点邻域畸变问题,弥补了死区效应所导致的输入电压利用率低以及输出电压谐波含量大的缺点.理论分析、仿真及实验验证了所提解结耦单极性移相调制策略及优化死区设置方法的可行性和有效性.%The topology of single-phase high-frequency link inverter (SPHFLI) is composed of high-frequency transformer, primary-side high-frequency inverter of the high-frequency transformer, output matrix converter/cycloconverter in the secondary side, and output filter. The high-frequency link inverter has the advantages of isolated power conversion and bidirectional flow of energy, as well as the difficulty of bidirectional switch commutation control. A De-Re-coupling uni-polarity phase-shifted modulation strategy for the topology of the SPHFLI was proposed in this paper. Without any auxiliary circuits and switch commutation overlap of the cycloconverter, this strategy can achieve natural commutation for all power switches in the cycloconverter with zero voltage switching (ZVS) as well as free-wheeling in the inductance of filter with no high voltage press impact. Then, a method of optimizing dead zone setting is also studied in this paper. Accordingly, the neighborhood distortion of zero crossing point of output voltage can be effectively improved under the control of the uni-polarity phase-shifted modulation strategy. The compensation for low utilization of the input voltage and the large harmonic content of the output voltage caused by the dead time effect can also be gained. The feasibility and effectiveness of the proposed strategy and the optimized dead-time setting method are verified through theoretical analysis, simulations and experiments.
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