基于高频环整半周控制的交交变换器研究

Analysis of AC Converter Based on Full Half Cycle Control of High Frequency Loop

高频交流环功率变换装置可将频率固定的高频交流电压合成幅值和频率可调的低频电压,为提高效率,整个变换过程需一步完成。设计了一种新型的控制策略,输出电压波形是由输入的高频离散半周期脉冲数目拼凑合成,且每个开关管都在零电压条件下转换,即高频环整半周调制策略,可将高频电压低失真地合成低频电压,克服了传统硬开关控制的缺点,变换器可适应不同的负载特性。实验表明,该控制策略具有可行性与合理性,整个装置具有较高的效率,且对开关管的损耗问题解决有重要意义。

High frequency AC loop power converter can synthesize low frequency voltage with fixed frequency AC voltage and adjustable frequency.In order to improve efficiency,the whole conversion process needs to be completed in one step.A new control strategy was designed.The output voltage waveform was composed of the number of input high frequency discrete half-cycle pulses,and each switch was converted under zero voltage condition.That is,the full half-cycle modulation strategy of high frequency loop can synthesize low frequency voltage with low distortion of high frequency voltage,overcome the shortcomings of traditional hard switching control,and the converter can adapt to different load characteristics.Experiments show that the control strategy is feasible and reasonable,the whole device has high efficiency,and has important significance for solving the loss problem of switch.