【摘要】 详细比较分析了当前交-交变频技术的特点,在此基础上提出了变脉宽斩波控制型脉冲阻塞式交-交变频原理。利用单个功率器件构成双向交流开关,施加于传统的单相交流调压电路并进行相应的改造,实现了单个功率器件的单相交-交变频变压目的。通过周期性地阻塞和放行网频正弦半波,获得频率可调的输出电压;采用按正弦规律变化的变脉宽高频脉冲信号对输出电压包含的网频正弦半波进行斩控,获得了幅值可调的输出电压,并且具有较好的正弦度。根据面积等效原理,对变脉宽斩波控制方式进行了详细的理论分析,推导出了变脉宽斩波控制方式中相应占空比的数学表达式。在PSPICE环境下进行了单相系统的仿真研究,并完成了相关实验。仿真和实验结果一致,并且与文中的理论分析结果也完全一致,从而验证了本文提出的交-交变频原理的正确性及PWM控制的可行性。更多还原

【Abstract】 The characteristic of present AC/AC converter technology is analyzed in detail,and the plugged pulse fashion AC/AC converter principle of variable pulse width chopping control type is presented.A bidirectional ac switch constructed by one power device is applied into the traditional circuit of ac voltage-adjusted,and the circuit is altered properly,so the aim of single phase AC/AC converter is realized which needs only one power device in the system.To make the frequency of output voltage adjustable,the sine half wave of net frequency is plugged and passed periodically.The high frequency pulse signal of variable pulse width varied by the sine regularity is used to chop the sine half wave of net frequency included in the output voltage to make the amplitude of output voltage adjustable too,and the waveform is approximate to sinewave.The principle of variable pulse width chopping control fashion is analyzed particularly according to the area equivalent theory.The algorithmic expression of duty cycle is deduced out.On the foundation of the above contents,the single phase AC/AC converter system is simulated under the environment of PSPICE and the corresponding experiments are completed.The simulation results are in consistent with experimental results,and the same as the theory analysis entirely.So,the new AC/AC principle and PWM control rule presented in this paper is verified to be proper and feasible.更多还原