Quasi-Interleaved Current Control for Switch-Linear Hybrid Envelope-Tracking Power Supply
Quasi-Interleaved Current Control for Switch-Linear Hybrid Envelope-Tracking Power Supply
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DOI：
10.1109/tpel.2017.2735485
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发表时间：
2018-06
影响因子：
6.7
通讯作者：
Yazhou Wang;X. Ruan;Q. Jin;Yang Leng-;F. Meng;Xiaowei Zhu
中科院分区：
文献类型：
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作者：
Yazhou Wang;X. Ruan;Q. Jin;Yang Leng-;F. Meng;Xiaowei Zhu
在无线通信系统中，功率跟踪（ET）技术可以大大提高功率放大器的效率。在电子束电源的结构中，开关线性混合（SLH）结构可以同时获得高跟踪带宽和高效率。本文提出了一种串并联结构的SLH ET电源的实现方案，它包括一个多电平变换器、一个线性放大器和两个降压变换器。两个降压转换器采用无电流传感器预测控制，并工作在临界导通模式（CRM）。为了保证CRM的运行，并提供尽可能多的负载电流，准交错电流控制方案，提出了两个降压变换器。此外，提出了一种峰值电流限制方法，以防止两个交错的降压转换器的输出电流过度超过负载电流，避免线性放大器中的功率损耗的增加。最后，制作了跟踪带宽为5 MHz、输出电压为9.6- 26.4V、平均输出功率为20 W的样机。跟踪宽带码分多址信号包络时，总的测量效率为81.0%，归一化均方误差为0.28%。
An envelope-tracking (ET) technique can greatly enhance the efficiency of the power amplifier in wireless communication system. Among the structures of the ET power supply, the switch-linear hybrid (SLH) structure can obtain both high-tracking bandwidth and high efficiency. An implementation of series–parallel-form SLH ET power supply is proposed in this paper, which includes one multilevel converter, one linear amplifier, and two buck converters. The two buck converters adopt current sensor-less prediction control and are operated at critical conduction mode (CRM). In order to ensure the operation of CRM and provide as much load current as possible, a quasi-interleaved current control scheme is proposed for the two buck converters. Moreover, a peak current restriction method is proposed to prevent the output current of the two interleaved buck converters from excessively exceeding the load current, avoiding the increase of the power loss in the linear amplifier. Finally, a prototype is fabricated with the specifications as 5-MHz tracking bandwidth, 9.6–26.4-V output voltage, and 20-W average output power. The overall measured efficiency is 81.0%, and the normalized-mean-square error is 0.28% when tracking the envelope of wideband code division multiple access signal.