Fast detector for surging or sudden drawdown voltages, and method

Abstract

A method for detecting sudden-up and sudden-down of voltage includes generating reference sine signal with the same phase and fixed amplitude as voltage signal of power supply, rectifying power supply voltage signal and reference sine signal then comparing rectified power supply voltage signal with rectified reference sine signal for obtaining detection result to present whether voltage is sudden-up or sudden-down. 本发明提供一种简单快速地检测电压突升和突降的方法和装置。本发明的电压突升和突降的检测方法包括以下步骤：产生与电源电压信号同相固定幅度的参考正弦信号；对电源电压信号和参考正弦信号进行整流；将整流后的电源电压信号与整流后的参考正弦信号进行比较得到表示电压是否突升或突降的检测结果。本发明的检测方案仅需1/4个振荡周期就能检测到电压的突升和突降，从而能够显著地提高响应速度。并且，本发明可以使用模拟电路很容易地实施，并且不必数字电路，从而实现本发明的成本也得到降低。