摘要
在交流方波电镀电源的输出控制中,需要获得脉冲宽度可调同时有死区时间控制的控制脉冲信号来触发大功率开关管,常规的控制芯片不能满足要求,因此只能通过单片机的控制方式来实现;本研究中的单片机正好没有互补PWM输出功能,针对该问题利用单稳态电路原理设计出一款既能得到PWM互补输出,同时又能够控制死区时间的逻辑电路;常规门电路的时差响应问题给输出带来可致命的干扰信号,利用MOS管搭建异或门电路,削弱了干扰信号的幅值,成功地将干扰信号过滤掉;最终得到输出稳定可靠、互补、死区时间可调整的PWM信号。
Under the output control of AC square wave plating power supply the pulse signal in which pulse width is adjustable and dead time can be control is used to trigger the high powers switching tube.However the conventional control chip can＇t meet those requirements,the control method of SCM are able to get those goals.According to the problem that some single-chip microcomputers is lack of PWM output,a logic circuit,which has functions of complementary PWM output and controlling the dead time,is designed on the basis of monostable circuit principle.However,the response to the time difference of conventional gate circuit causes a great quantity of fatal interfering signals to the output.This paper has developed a type of XOR gate circuit by using MOS tube structures,which can attenuate the amplitude of the interference signal,and thus filter out the interference signal successfully.Finally we can get a stable,reliable and complementary PWM output signal with adjustable dead time by this method.
出处
《电焊机》
北大核心
2012年第3期44-46,91,共4页
Electric Welding Machine
